eni spa 03774.MAC.MEC.

FUN
Rev. 2 Sep-2013
exploration & production division
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REVISION HISTORY

Rev.0 Issued.

Rev.1 General revision.

Rev.2 General revision.

New and customized requirements are set in addition to those defined by the reference
standard API 616 “Gas Turbines for the Petroleum, Chemical, and Gas Industry
Services” for the purchase of gas turbine packages for power generation or mechanical
drive (pump, compressor).

Changed code from SPC to FUN.

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Contents
1.  GENERAL ...................................................................................................................................... 5 
1.1  Scope..................................................................................................................................... 5 
1.2  Terms and Definitions............................................................................................................ 5 
1.3  Glossary................................................................................................................................. 6 
1.4  Units of Measurement ........................................................................................................... 7 
1.5  Statutory Requirements......................................................................................................... 7 
1.6  Contractor’s Responsibilities ................................................................................................. 7 
1.7  Sub-suppliers List .................................................................................................................. 7 
1.8  Language............................................................................................................................... 8 
2.  CODES, STANDARDS AND REGULATIONS............................................................................... 8 
2.1  Project Specifications ............................................................................................................ 8 
2.2  Industry Codes and Standards .............................................................................................. 8 
2.3  International Regulations....................................................................................................... 9 
2.4  Company General Specifications .......................................................................................... 9 
2.5  Company Data Sheets .......................................................................................................... 9 
2.6  Conflicting Requirements ...................................................................................................... 9 
2.7  Deviations and Exclusions..................................................................................................... 9 
3.  SCOPE OF SUPPLY.................................................................................................................... 10 
3.1  Gas Turbine Package.......................................................................................................... 10 
3.2  Battery Limits ....................................................................................................................... 13 
3.3  Exclusions of Supply ........................................................................................................... 14 
3.4  Supply Options .................................................................................................................... 14 
4.  HEALTH, SAFETY AND ENVIRONMENTAL REQUIREMENTS ................................................ 14 
4.1  Health, Safety and Environmental Regulations................................................................... 14 
4.2  Area Classification............................................................................................................... 14 
4.3  Noise Control ....................................................................................................................... 14 
4.4  Combustion Emission Control ............................................................................................. 15 
4.5  Exhaust Stack...................................................................................................................... 15 
4.6  Lube Oil System .................................................................................................................. 15 
4.7  Inlet Air System.................................................................................................................... 15 
5.  QUALITY ...................................................................................................................................... 15 
5.1  Quality Management System .............................................................................................. 15 
5.2  Project Quality Control Plan ................................................................................................ 15 
6.  BASIC DESIGN............................................................................................................................ 16 
6.1  General ................................................................................................................................ 16 
6.2  Design Life........................................................................................................................... 17 
6.3  Performance ........................................................................................................................ 17 
6.4  Pressure Casings ................................................................................................................ 18 
6.5  Combustor and Fuel Nozzles .............................................................................................. 18 
6.6  Rotating Elements ............................................................................................................... 18 
6.7  Dynamics ............................................................................................................................. 19 
6.8  Bearings and Bearing Housings .......................................................................................... 20 
6.9  Lubrication & Control Oil System......................................................................................... 20 
6.10  Materials .............................................................................................................................. 21 
6.11  Welding and NDE ................................................................................................................ 21 
7.  ACCESSORIES ........................................................................................................................... 21 
7.1  Starting and Helper Driver ................................................................................................... 21 
7.2  Load Gear............................................................................................................................ 22 
7.3  Couplings and Guards......................................................................................................... 22 
7.4  Baseplate............................................................................................................................. 22 
7.5  Instrumentation and Control ................................................................................................ 23 
7.5.1  Gas Turbine Control and Protection System................................................................... 23 
7.5.2  Machine Monitoring System ............................................................................................ 25 
7.5.3  Continuous Emission Monitoring System........................................................................ 25 
7.5.4  Instrumentation ................................................................................................................ 25 
7.6  Electrical Equipment............................................................................................................ 25 
7.7  Piping................................................................................................................................... 26 
7.8  Combustion Air Inlet and Exhaust Systems ........................................................................ 27 
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7.8.1  Inlet System ..................................................................................................................... 27 

7.8.2  Power Augmentation Devices ......................................................................................... 28 
7.8.3  Exhaust System............................................................................................................... 28 
7.9  Cooling Water System......................................................................................................... 29 
7.10  Compressor Blow-off System .............................................................................................. 29 
7.11  Compressor Washing System ............................................................................................. 29 
7.12  Fuel and Fuel System.......................................................................................................... 29 
7.12.1  Gaseous Fuel .............................................................................................................. 29 
7.12.2  Liquid Fuel ................................................................................................................... 30 
7.12.3  Fuel System................................................................................................................. 30 
7.12.4  Dual Fuel Systems....................................................................................................... 31 
7.12.5  Emission Suppression System .................................................................................... 31 
7.13  Painting and Coating ........................................................................................................... 32 
7.14  Enclosure............................................................................................................................. 32 
7.15  Thermal Insulation and Personal Protection ....................................................................... 33 
7.16  Earthing System .................................................................................................................. 34 
7.17  Nameplates & Rotational Arrows......................................................................................... 34 
7.18  Special Tools ....................................................................................................................... 35 
7.19  Spare Parts.......................................................................................................................... 35 
7.20  Assembly Degree ................................................................................................................ 36 
8.  OPERABILITY AND MAINTAINABILITY ..................................................................................... 36 
9.  INSPECTIONS AND TESTS........................................................................................................ 36 
9.1  General ................................................................................................................................ 36 
9.2  Inspections........................................................................................................................... 37 
9.3  Tests .................................................................................................................................... 37 
9.3.1  Rotor Overspeed Test ..................................................................................................... 37 
9.3.2  Mechanical Running Test ................................................................................................ 37 
9.3.3  Performance Test ............................................................................................................ 37 
9.3.4  Reliability Test ................................................................................................................. 37 
10.  PRESERVATION, STORAGE, PACKING AND TRANSPORT ................................................... 38 
11.  WARRANTY AND GUARANTEES .............................................................................................. 38 
11.1  Warranty .............................................................................................................................. 38 
11.2  Performance Guarantees .................................................................................................... 39 
12.  CONTRACTOR’S DOCUMENTATION........................................................................................ 39 
12.1  Tender Documentation ........................................................................................................ 39 
12.2  Contract Documentation...................................................................................................... 39 
13.  SPECIAL REQUIREMENTS ........................................................................................................ 39 
13.1  Sour Gas Service ................................................................................................................ 39 
13.2  Coastal Installations ............................................................................................................ 40 
13.2.1  Inlet Air System............................................................................................................ 40 
13.3  Offshore and Marine Installations........................................................................................ 40 
13.3.1  Vessel Installations...................................................................................................... 40 
13.3.2  Weight Control ............................................................................................................. 40 
13.3.3  Inlet Air System............................................................................................................ 40 
13.4  Desert Installations .............................................................................................................. 41 
13.4.1  Emissions Control........................................................................................................ 41 
13.4.2  Enclosure..................................................................................................................... 41 
13.4.3  Inlet Air System............................................................................................................ 41 
13.5  Arctic Installations................................................................................................................ 41 
13.5.1  Materials ...................................................................................................................... 41 
13.5.2  Enclosure..................................................................................................................... 42 
13.5.3  Oil Cooler..................................................................................................................... 42 
13.5.4  Inlet Air System............................................................................................................ 42 
13.5.5  Fuel System................................................................................................................. 42 
13.6  Tropical Installations............................................................................................................ 42 
13.6.1  Inlet Air System............................................................................................................ 42 
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1. GENERAL
1.1 Scope
This General Specification defines requirements and gives recommendations for gas
turbines, based on “Gas Turbines for the Petroleum, Chemical, and Gas Industry Services”
API Standard 616, 5th edition.
This Specification amends and supplements various clauses of API 616. Furthermore, it
summarizes (highlights) some important clauses of API 616.
With respect to API 616, paragraphs are marked as follows:
­ clause added to API 616;
™ clause that modifies API 616;
y clause that makes a decision, as required by API 616;
9 clause that summarizes the corresponding API 616 clause.
When input by Company is required for the specific Project, it is marked as follows: (Í).

1.2 Terms and Definitions

­ The “Company” is the party that initiates the project and ultimately pays for its design
and construction. The Company will generally specify the technical requirements.
­ The “Contractor” is the party that carries out all or part of the design, engineering,
procurement, installation, and commissioning or management of a project or operation
of a facility. The Company may sometimes undertake all or part of the duties of the
Contractor, e.g. when the Company awards the Contract directly to the Manufacturer.
­ The “Manufacturer” is the party that manufactures the gas turbine and performs the
design, engineering, procurement, installation, commissioning and management of the
gas turbine package, procuring other components from Sub-suppliers.
­ The “Sub-supplier” is the party that manufactures or supplies equipment and services to
perform the duties specified by the Manufacturer, typically sub-systems and
components of the main equipment.
­ The contractual structure may be one of the following:
o Company → (EPC) Contractor → Manufacturer → Sub-suppliers, or
o Company → (EPC) Contractor=Manufacturer → Sub-suppliers
­ The “gas turbine” comprises the turbo-machine and its auxiliary equipment (lube, seal,
control etc.).
­ The “gas turbine package”, in addition to the gas turbine, comprises: the inlet air
system, exhaust system, stack, enclosure, off-base equipment, all the valves,
instrumentation and the interconnecting piping that form a complete and self-sufficient
unit that needs fuel, utility fluids and electrical power to operate.
­ The “Project”, as related to requirements, indicates those set by the Company in the
specific Project documentation.
­ The word “shall” indicates a requirement.
­ The word “should” indicates a recommendation.
­ “Base load” is the continuous power developed by the gas turbine when it is operated at
the firing temperature (TIT) defined by the Manufacturer for lifetime optimized
operation. This condition corresponds to the 100% load.
­ “Peak load” also known as “maximum continuous load” is the continuous power
developed by the gas turbine when it is operated at the firing temperature (TIT) defined
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by the Manufacturer for power optimized operation. This load setting reduces the life of
the hot gas path parts.
™ “ISO-rated power” is the shaft power developed at 15 °C ambient temperature, 1013.25
mbar atmospheric pressure and 60% relative humidity, with zero inlet and exhaust
pressure losses.
­ “Gas turbine-generator required power” is the net power output (at generator terminals)
that is required of the gas turbine-generator package in a power generation application.
This power is specified by the Company.
­ “Driven equipment required power” is the maximum power required by the driven
equipment (compressor or pump) in a mechanical drive application.
™ “Site rated power” is the shaft power developed by the gas turbine when it is operated
in a new and unfouled condition, at site conditions of air inlet temperature, air inlet
pressure, exhaust back pressure, reference fuel composition and with a base load
setting. The rated power satisfies the specified margin over the gas turbine-generator
required power – in case of power generation application – or the driven equipment
required power – in case of mechanical drive. The site rated power is the gas turbine
net power output (after subtracting the gas turbine auxiliaries loads from the gross
power output). The rated power is specified by the Manufacturer.
9 “Potential maximum power” is the expected power capability when the gas turbine is
operated at maximum allowable firing temperature, rated speed or under other limiting
conditions as defined by the Manufacturer and within the range of specified site values.

1.3 Glossary
ADL administrative delay time
BOP balance of plant
CCR central control room
CEMS continuous emission monitoring system
CMMS computerized maintenance management system
CoG center of gravity
DCS distributed control system
DDSO device dependent subsynchronous oscillations
DLE dry low emissions
DLN dry low NOx
EOH equivalent operating hours
GT gas turbine
GTCPS gas turbine control & protection system
IGV inlet guide vanes
LDT logistic delay time
LHV lower heating value
MDT mean down time
MMS machine monitoring system
MTBF mean operating time between failures
MTBO mean time between overhauls
MTTF mean time to failure
MTTO mean time to overhaul
MTTR mean time to recovery
PM particulate matter
PMI positive material identification
ppm vd parts per million by volume dry
RPM revolutions per minute
SCR selective catalytic reduction
SIL safety integrity level
SPL sound pressure level
SSR subsynchronous resonance
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TIT turbine inlet temperature

UHC unburned hydrocarbons

1.4 Units of Measurement

™ The SI system of units and dimensions is used in this Specification. Any data or
drawings related to equipment supplied to this Specification shall use the SI system.
The U.S. Customary system may be employed for piping components dimensions
(inches).
­ Pressure shall be relative and it shall be expressed in bar(g).

1.5 Statutory Requirements

­ Contractor shall fully comply with the legislation of the Country where the gas turbine
package is installed.
­ The Equipment supplied to this Specification adhere to the Industry Codes and
Standards referenced in Section 2.2 and the Company Specifications in Section 2.3.
The Contractor’s proposal should list other Codes and Standards to which equipment is
designed and built.

1.6 Contractor’s Responsibilities

­ This Specification is primarily intended to define the minimum requirements and does
not relieve the Contractor of its responsibility for the design, performance and safe
operation of the whole package.
­ The Contractor shall be responsible for the design, performance, guarantees, co-
ordination, manufacture, inspection, testing, preservation and packaging of the entire
gas turbine package, in accordance with the requirements of this General Specification
and Project Specifications and Data Sheets. This shall include as a minimum:
o provision of documentation;
o control and co-ordination of Manufacturer and Sub-suppliers;
o compliance with Statutory Requirements, Codes and Standards;
o identification of all technical exceptions and deviations from this General
Specification, Project Specifications and all referenced Industry Codes and
Standards;
o consideration of equipment design and shipping arrangements for ease of delivery to
the site;
o provision of all necessary design certification.
­ The Contractor shall assure that the Manufacturer and all Sub-suppliers comply with
the requirements of this Specification and all reference Standards.

1.7 Sub-suppliers List

­ The Contractor shall submit to the Company for approval a qualified Sub-supplier list
with relevant references and experience with similar application.
­ Any deviation from such list, for whatever reason, shall be notified to the Company
before the relevant suborder.
­ Suborders to Sub-suppliers not included in the qualified Sub-supplier list shall not be
placed without the written approval of the Company.
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1.8 Language
­ All drawings, data sheets, reports, manuals, correspondence and any other written
information shall be in the English language.
­ The nameplates shall be in the English language only.
­ Safety signs and indications (label, tags, etc.) at site shall be both in the English
language and in the local language, as required in the Project Specification (Í).

2. CODES, STANDARDS AND REGULATIONS

­ The Codes, Standards and Regulations listed below shall be applicable. Unless
specifically designed by date, the latest edition of each publication shall be used,
together with any amendments/supplements/revisions thereto.

2.1 Project Specifications

­ Additional requirements, defined in the Project Specifications and Procedures (Í),
shall be adhered to by the Contractor.

2.2 Industry Codes and Standards

API Std 616 Gas Turbines for the Petroleum, Chemical, and Gas Industry Services
API Std 613 Special Purpose Gear Units for Petroleum, Chemical and Gas Industry
Lubrication, Shaft-sealing, and Control-oil Systems and Auxiliaries for
API Std 614
Petroleum, Chemical and Gas Industry Services
API Std 670 Vibration, Axial Position, and Bearing Monitoring Systems
API Std 671 Special Purpose Couplings for Refinery Service
ASME V, VIII, IX Boiler and Pressure Vessel Code
ASME PTC 22 Gas Turbines Performance Test Codes
ASME B16 series Standards for Piping
ASTM Standards for Materials, Welding and Test Methods
EN 287 Approval testing of welders; fusion welding
EN 288 Specification and qualification of welding procedures for metallic materials
ISO 281 Rolling bearings -- Dynamic load ratings and rating life
ISO 2314 Gas Turbines Acceptance Tests
Mechanical vibration -- Evaluation of machine vibration by measurements
ISO 7919-4
on rotating shafts -- Part 4: Gas turbine sets with fluid-film bearings
ISO 9001 Quality management systems - requirements
ISO 9606 Approval testing of welders - fusion welding
ISO 9956 Specification and approval of welding procedures for metallic materials
Petroleum, petrochemical and natural gas industries -- Flexible couplings
ISO 10441
for mechanical power transmission -- Special-purpose applications
ISO 10474 Steel and steel products - inspection documents
Mechanical vibration -- Evaluation of machine vibration by measurements
ISO 10816-4
on non-rotating parts -- Part 4: Gas turbine sets with fluid-film bearings
Gas Turbines - Exhaust gas emission - Part 1: Measurement and
ISO 11042
evaluation
IEC 60079 series Explosive Atmospheres
IEC 60034 series Rotating Electrical Machines
PED 97/23/EC Pressure Equipment Directive
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2.3 International Regulations

FAA AC 70/7460-1K Obstruction Marking and Lighting

2.4 Company General Specifications

05497.VAR.ELE.STD Construction Methods for Electrical Material for Tropical Climates
(Tropicalization)
05882.COO.MEC.PRG 2 Years Operation Spare Parts for Mechanical Equipment and Machines
06778.ICO.ELE.STD Skid or Package Units - Typical Earthing Details
07423.PKG.GEN.SDS Inspection and Test of Package Supplies
20000.VAR.PAI.FUN Protective Coating, Galvanizing and Metalizing for internal and external
Surfaces of Offshore and Onshore Structures and related Components
20150.PKG.STA.FUN Instrumentation Automation Plants Included in Rotary Machine Package
20161.EQP.ELE.FUN Low Voltage Switchgear and Control Gear Assemblies (up to 1000 V AC
1500 DC)
20162.EQP.ELE.FUN AC & DC Uninterruptible Power Supply Systems and DC Back-up Power
Supply Systems
20167.EQP.ELE.FUN Asynchronous Motors
20178.EQP.ELE.FUN Low Voltage Variable Speed Electric Drives
20179.EQP.ELE.FUN Medium and High Power Variable Speed Electric Drive
20182.COO.GEN.SDS Spare Parts
20185.COO.GEN.SDS Handling and Protection of Materials and Equipment
20186.COO.GEN.SDS Weight Control System
20187.COO.GEN.SDS Weight Control System for Engineering
20193.VAR.SAF.SDS Selection of Sensors and Gas and Fire Detection Criteria
20220.PKG.ETI.SDS Prefabricated Cabins for Electric Machinery and Equipment

2.5 Company Data Sheets

MOD.MEC.TUR.001 Gas Turbine Technical Data Sheets (TDS)
MOD.MEC.TUR.101 Gas Turbine Inspection & Test Data Sheets (IDS)
MOD.MEC.TUR.201 Gas Turbine Required Document Data Sheets (DDS)

2.6 Conflicting Requirements

™ In the event of conflict between documents relating to the Contract, the following
hierarchy of documents shall apply:
1. Local Regulations of the Country where the equipment is installed;
2. Project Specifications and Data Sheets;
3. Company General Specifications;
4. International Codes & Standards.
­ Any apparent conflict between the requirements of this Specification and any other
relevant document in the Contract shall be notified to the Company for clarification
purposes.

2.7 Deviations and Exclusions

­ The Contractor shall identify and list all deviations and exclusions to the Company
requirements.
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­ Unless deviations and exclusions are explicitly signaled by the Contractor in its
Proposal and agreed upon with the Company, the Contractor’s supply shall be
considered fully compliant with all the Company requirements.

3. SCOPE OF SUPPLY
3.1 Gas Turbine Package
­ The supply shall comprise, but shall not be limited to:
o gas turbine;
o combustion system;
o ignition system;
o fuel gas system, including:
ƒ dry low emission system (DLE);
ƒ strainer;
ƒ shut-off valve;
ƒ vent valve;
ƒ automatic fast shut-off valve;
ƒ flow control valve;
o liquid fuel system, if dual fuel GT;
o IGV system;
o compressor blow-off system;
o load gear, if required by the driven equipment;
o load coupling(s) w/ guard;
o cooling water system, including:
ƒ pumps;
ƒ water/air cooler;
ƒ expansion tank;
ƒ interconnecting piping, valves, instrumentation.
o lube & control oil system, including:
ƒ duplex lube oil filter;
ƒ oil/air cooler;
ƒ shaft driven or AC motor driven main oil pump;
ƒ AC motor driven auxiliary oil pump;
ƒ DC motor driven emergency oil pump;
ƒ lube oil temperature control valve;
ƒ lube oil pressure regulating valve;
ƒ oil reservoir with immersed electric heaters;
ƒ oil/vapor separator skid (incl. oil/vapor separator, extractor fan, drain box);
ƒ duplex control oil filter;
ƒ control oil pressure regulating valve;
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ƒ accumulator;
ƒ interconnecting piping, valves, instrumentation;
ƒ control console.
o compressor on-off line washing skid, including:
ƒ water tank with electric heater;
ƒ AC motor driven water pump;
ƒ spray nozzles;
ƒ detergent storage tank;
ƒ detergent venturi ejector;
ƒ interconnecting piping, valves, instrumentation;
ƒ control console;
ƒ consumables;
ƒ special tools.
o mobile engine cleaning cart;
o GT casing cooling & bearing sealing air system;
o boroscope connections;
o control air system;
o GT control & protection system (GTCPS), including:
ƒ control system;
ƒ protection system;
ƒ electrical cabin control console (lights, switches, buttons, HMI operator
station, etc.);
ƒ CCR HMI operator station;
ƒ HMI engineering station;
ƒ DCS interface (hardwired and serial).
o machine monitoring system (MMS);
o rotor jacking oil system;
o maintenance lifting system, if required (Í);
o other lifting equipment (shackles, lugs, beams, jackscrews, etc.), if necessary;
o GT starting system;
o GT turning gear system;
o liquid drain system;
o boroscope openings;
o baseplate and sump for leakages and drains collection and recovery;
o anchor bolts;
o foundation templates, embedded pieces, etc.;
o combustion air inlet system, including:
ƒ weather louver;
ƒ inlet filter house w/ supporting structure;
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ƒ air filter(s);
ƒ ducting;
ƒ silencer;
ƒ filter cleaning system;
ƒ inlet manifold;
ƒ ladders & platforms.
o combustion air exhaust system, including:
ƒ exhaust diffuser and equalizing section;
ƒ ducting;
ƒ silencer;
ƒ expansion joint;
ƒ ladders & platforms.
o exhaust stack, including:
ƒ stack damper, if required;
ƒ aircraft warning lights;
ƒ lightning protection;
ƒ thermal insulation;
ƒ ladders & platforms.
o continuous emission monitoring system (CEMS), if required (Í);
o anti-icing system, if necessary;
o air purge system, if dual fuel GT;
o GT enclosure, complete with:
ƒ access doors;
ƒ removable acoustic panels;
ƒ structural steel frame;
ƒ penetrating elements for cabling and piping;
ƒ HVAC system (main/stand-by fan, inlet duct, filter, outlet ducts);
ƒ fire & gas detection system;
ƒ fire extinguishing system (fixed);
ƒ hand-held CO2 fire extinguishers;
ƒ normal lighting system (AC) and emergency/safety lighting system (DC);
ƒ platforms, catwalks, ladders and stairs.
o electrical cabin, complete with:
ƒ HVAC system;
ƒ fire detection system;
ƒ fire extinguishing system (fixed);
ƒ hand-held CO2 fire extinguishers;
ƒ lighting system (normal and emergency/safety);
o grounding connections on-skid;
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o GT thermal insulation and personal protection;

o all supporting structures;
o all instrument and electrical cable tray, wiring and junction box(es) complete of cable
glands, up to skid edge;
o MV switchgear, if required;
o LV switchgear;
o motor control center (MCC);
o DC/UPS w/ battery modules;
o electrical cabin power cabling;
o interconnecting power cabling (within skid and between skids);
o interconnecting signal cabling (within skid and between skids);
o emergency eyewash station;
o GT start variable frequency drive (VFD), if necessary;
o DC back-up lube pump starter;
o access platforms, walkways & ladders;
o interconnecting piping between the gas turbine skid and the auxiliary skids;
o special tools required for disassembly and maintenance, if applicable;
o surface preparation and coating/painting;
o nameplates;
o commissioning & start-up spare parts.

3.2 Battery Limits

­ Battery limits depend on the specific configuration and, as such, should be defined at
Project level (Í). However, typical battery limits are:
o driven equipment coupling;
o unit baseplate: anchor bolts to be embedded in the concrete foundation or 3-point
mount gimbals;
o off-base equipment: anchor bolts;
o gas turbine combustion air inlet system: inlet face of air filter house;
o gas turbine exhaust gas system: vertical stack outlet to the atmosphere;
o all liquid drains;
o all vents to atmosphere;
o fuel gas inlet;
o fuel oil inlet, if present;
o fuel gas vent to flare;
o lube/hydraulic oil filling;
o cooling water inlet;
o compressor washing system: water and detergent filling;
o ventilation: hot air discharge on unit enclosure;
o MV incoming feeder, if required;
o LV incoming feeder;
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o earthing connections on baseplate(s);

o earthing connections on electrical cabin;
o GTCPS junction boxes to/from DCS.

3.3 Exclusions of Supply

­ Typical exclusions are:
o civil works and foundations for each skid;
o multi-pair cables, optical fiber cables, and other cables from package junction boxes
to DCS;
o connections to the primary grounding system.

3.4 Supply Options

­ Optional items will be defined by the Project documentation, but the following may be
required:
o power augmentation device (inlet cooler or fogging);
o fuel gas calorimeter system, including:
ƒ insulated & pressurized cabinet w/ gas analyzer, HVAC, local panel;
ƒ sample probe;
ƒ calibration gas bottle box;
ƒ valves, instrumentation, piping.
o spare parts for 2-year operation;
o capital spare parts;
o supervision for site installation, commissioning and start-up;
o training of personnel.

4. HEALTH, SAFETY AND ENVIRONMENTAL REQUIREMENTS

4.1 Health, Safety and Environmental Regulations
­ The Contractor shall be responsible for ensuring that the goods and services supplied
meet all applicable regulations on health, safety and environmental issues.
­ The equipment shall be designed to operate safely and satisfactorily in all expected
combinations of process, utilities, climates and environmental conditions including start-
up, shutdown, part load operation, and emergency cases, while retaining the overall
system security, reliability and availability.

4.2 Area Classification

­ Electrical equipment protection level shall be appropriate to the hazardous area
classification of the gas turbine installation, as specified in MOD.MEC.TUR.001 (Í).

4.3 Noise Control

™ Limiting and attenuation of the sound pressure level (SPL) of all equipment furnished
shall be the responsibility of the Contractor. The equipment furnished by the Contractor
shall conform to the maximum allowable sound pressure level specified by the
Company in MOD.MEC.TUR.001 (Í). In order to determine compliance, the Contractor
shall provide both maximum sound pressure and sound power level data per octave
band for each principal component supplied.
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­ The sound pressure level of the equipment shall be submitted with the proposal and it
shall be guaranteed by the Contractor. Reference is made to section 11.2 “Performance
Guarantees” below.
­ An acoustical enclosure, housing the gas turbine, its auxiliaries and the driven
equipment, shall be provided. Reference is made to Section 7.14 “Enclosure”.

4.4 Combustion Emission Control

­ Gas turbine combustion emissions shall comply with the local regulations.
™ The Company will specify the maximum allowable emissions levels at the Package
boundaries (Í). The control of exhaust emissions levels of the package shall be a joint
effort of the Contractor and the Company. Any restrictions on the gas turbine’s speed or
load range related to emission control shall be stated in the proposal. The Contractor
shall state in his proposal expected emissions levels consistent with the Company’s
specified fuel properties and site operating conditions. The Contractor shall supply the
gas turbine combustion emission suppression system when it is required to meet the
specified levels of NOx, CO, and unburned hydrocarbons in the gas turbine’s exhaust
gas. Any restrictions on the speed range or load range of units with emission control
shall be stated in the proposal.
­ Reference is made to Section 11.2 “Performance Guarantees” for the combustion
emission parameters to be guaranteed.

4.5 Exhaust Stack

­ The exhaust stack shall be sized in compliance with the local regulations for
combustion and noise emissions.

4.6 Lube Oil System

­ Atmospheric vents from the lube oil system shall be provided with a filter coalescer to
minimize oil carryover to the atmosphere.

4.7 Inlet Air System

­ To detect flammable gas in the atmosphere, a flammable gas detector should be
installed in a fast loop in the air inlet.

5. QUALITY
5.1 Quality Management System
­ The Contractor’s proposed quality management system shall be certified as in
compliance with the ISO 9001 Standard. The Contractor’s Quality Management System
Certification shall be valid for design, engineering, project management, manufacturing,
maintenance and service of the gas turbine package.
­ A non-numbered copy of the Contractor’s Quality Management System Manual shall be
submitted with the Proposal.
­ In the event that the quality management system of the Contractor’s first tier Sub-
suppliers is not certified as in compliance with the ISO 9001 Standard, the Contractor’s
shall submit to the Company the sub-supplier’s quality management system for
approval before issuing any suborder to that Sub-supplier.

5.2 Project Quality Control Plan

­ The Contractor shall issue a dedicated Quality Control Plan (QCP) including the tests
and inspections envisaged on all the equipment during fabrication. The QCP shall
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provide for the planned and systematic control of all quality-related activities performed
during design/development, production, installation or servicing (as appropriate to the
given system).
­ The QCP shall be subject to the Company’s review and approval during the bidding
phase and the Company will request, at its own discretion, progress and technical audit
reports throughout the duration of the Contract.
­ All materials shall be inspected and tested in accordance with the applicable Codes and
the Project Inspection Data Sheets. The Contractor shall issue a plan for the tests to be
performed in its own and its Sub-suppliers’ shops on raw, semi-manufactured and
finished materials in order to verify the compliance of the materials with the required
chemical, physical and mechanical characteristics.
­ The QCP shall include the procedures, inspections, tests, check points (R, W, H) for all
the critical phases of engineering, manufacturing, tests, preparation for shipment. For
each check point the Contractor shall indicate the applicable procedures, the
acceptance criteria and the attendance of Parties.
­ For each check point the Contractor shall indicate:
o Applicable Procedures;
o Acceptance criteria;
o Attendance of Parties (as per MOD.MEC.TUR.101).
­ Reference is made to Section 9 “Inspections and Tests” below.

6. BASIC DESIGN
6.1 General
­ Contractor shall not propose prototypes or modified gas turbine models.
y The output-shaft operating speed range of gas turbine units for mechanical-drive
applications shall be as specified on the datasheets. Where only one operating speed
is specified for an application, the speed range for single-shaft machines shall be 25%
(from 80% to 105% of rated speed), and the speed range for two or more shaft
machines shall be 55% (from 50% to 105% of rated speed).
™ Gas turbine units shall be designed for continuous service at each point of the specified
speed range and power range including potential maximum power. The Manufacturer
shall define the period between major overhauls when operating on reference gas fuel,
at base load.
9 The gas turbine design shall accommodate transient thermal gradients following
tripouts and shall permit immediate restarting subject to the driven equipment
restrictions. Gas turbine cold-start and hot-start restrictions shall be defined in the
proposal. The Company shall agree with the Manufacturer on consequences if the
restrictions must be exceeded.
y The equipment, including all auxiliaries, shall be suitable for operation under the
environmental conditions specified by the Company in the data sheets (Í). These
conditions shall include whether the installation is indoors (heated or unheated) or
outdoors (with or without a roof), maximum and minimum temperatures, unusual
humidity, and dusty or corrosive conditions. The unit and its auxiliaries shall be suitable
for shipment and installation under the specified conditions.
­ Industrial gas turbines (also known as heavy duty) shall be the preferred choice over
aeroderivative gas turbines for installations where mass and available space are not
limited. Also if the gas turbine fuel is a crude oil, residual fuel oil, very lean gas, refinery
mix gas or a gas that is subject to variations of the Wobbe Index of more than 10%,
then industrial gas turbines shall be selected. Aeroderivatives may be used for peaking
units in power generation.
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­ For mechanical drive applications with large speed variations (70% to 100%), a gas
generator with power turbine configuration should be the preferred choice. For power
generation, a single-shaft industrial gas turbine should be selected, due to the
frequency stability granted by its greater inertia, its simplicity and easier maintainability
A single-shaft gas turbine with a variable speed drive for mechanical drive applications
should not be the first choice.

6.2 Design Life

9 The equipment (including auxiliaries) covered by this Specification shall be designed
and constructed for a minimum service life of 20 years and at least 3 years of
uninterrupted operation. It is recognized that this is a design criterion and that hot
section inspections may be required; however, the required time between inspections
shall be no less than 8000 operating hours. The 8000-hour requirement applies to
base-loaded machines using sweet, dry gas fuel that meets manufacturer’s
specifications. The Contractor shall supply the service life and minimum uninterrupted
operation interval based on each specific application. The maintenance procedure
necessary to achieve these intervals shall also be supplied. For aeroderivative gas
turbines, the time required for intrusive (requiring parts removal) inspections shall be no
less than 12,000 operating hours. Nonintrusive inspections, e.g. those requiring the use
of a boroscope may be more frequent as required by the Manufacturer.
­ The equipment (including auxiliaries) shall be designed for maximum reliability and
availability.
­ For the purpose of establishing the total cost of ownership over the design life of the
equipment, the Contractor shall provide reliability and life cycle data, such as:
• Mean Time Between Failures (MTBF);
• Mean Time to Repair (MTTR);
• Mean Time Between Overhauls (MTBO);
• Mean Time to Overhaul (MTTO);

6.3 Performance
­ The Company required power at site conditions shall be attained with a base load
setting. The peak load setting shall not be considered to meet the power requirement.
­ Power-augmentation solutions, such as evaporative cooling, adsorption chilling, fogging
or water injection, should not be employed to meet the Company required power, due
to their operation and maintenance complexity, their requirement for water treatment
facilities and their water consumption.
™ The gas turbine shall be designed to provide site-rated power with no negative
tolerance in the new and unfouled condition. The gas turbine rating shall be based on
Manufacturer's actual experience.
­ For mechanical drive applications, the gas turbine shall be selected to have, at site
conditions and in the new and unfouled condition, a shaft power output at base load of
at least 110% of the driven equipment demand, inclusive of the load gear, if present,
and considering inlet and outlet systems losses. This power margin takes into account
the unrecoverable gas turbine losses (aging and compressor fouling) and the driven
equipment power margin.
­ For power generation applications, the gas turbine generator package shall be selected
to have, at site conditions and in the new and unfouled condition, a net output (at
generator terminals) at base load of at least 105% of the Company required power.
This power margin takes into account the unrecoverable gas turbine losses (aging and
compressor fouling).
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­ For power generation applications, the Contractor shall provide in the proposal the gas
turbine operational restrictions as to:
o the maximum positive/negative load step;
o the maximum positive/negative load gradient.
­ For mechanical drive applications, Company shall make available to the Contractor all
expected operating points because the maximum torque required from the gas turbine
driver will not necessarily be at maximum power or speed.(Í)

6.4 Pressure Casings

™ Casings shall be designed or suitable guarding shall be provided to contain all blade-off
events and the subsequent collateral damage, but not disk burst or overhung shaft
failure.

6.5 Combustor and Fuel Nozzles

9 The Contractor shall indicate the capabilities of the proposed combustion system by
advising maximum and minimum and the maximum allowable rate of change of the
Wobbe index.
™ Fuel nozzles shall be selected based on the fuel type and composition specified by the
Company. The Manufacturer shall guarantee that the selected nozzles can withstand
coking and fouling by combustion products and will not require servicing between
scheduled shutdowns.
™ Dual-fuel nozzles shall be provided with an air purge system: a) to prevent liquid fuel
from entering the gas fuel nozzles of the combustion chamber during liquid fuel
operation; b) to purge the liquid fuel nozzles of the combustion chamber during gas fuel
operation. The air supply should be taken from the turbine air compressor bleed
system.

6.6 Rotating Elements

­ On gas turbines for power generation, rotors shall be mechanically designed to
withstand the torque produced by the generator during a short circuit. The torque
considered shall be at least 6 times the full-load torque. Out-of-phase synchronization
shall also be considered in the mechanical design.
9 Gas generator rotors and rotors of single-shaft gas turbines shall be mechanically
designed to safely withstand momentary speeds up to 110 % of the gas turbine trip
speed settings throughout the Manufacturer-defined firing temperature range. The
Manufacturer shall state in the proposal any inspections that would be required, before
restart, after such momentary overspeed conditions have occurred.
9 In the event of an instantaneous loss of 100 % of site rated load and the driven inertia,
gas turbine rotors must be capable of safe operation without the blades, disks, or shafts
fracturing or separating as a result of the ensuing overspeed. The Manufacturer shall
state in the proposal any inspections or maintenance required before restart when
overspeed excursions exceed the normal overspeed trip limits.
­ When the air compressor corrosion is foreseen due to the site operating conditions, the
air compressor rotor and stator blades shall be either made of a non-corroding material
or shall have a non-corroding coating.
9 The blade natural frequencies shall not coincide with any source of excitation from 10%
below minimum governed speed to 10% above maximum continuous speed. If this is
not feasible, blade stress levels developed at any specified driven equipment operation
shall be low enough to allow unrestricted operation for the minimum service life defined
in Section 6.2. “Design Life”. Blades shall be designed to withstand operation at
resonant frequencies during normal warm-up. The Manufacturer shall state in the
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proposal the speeds below the operation range corresponding to such blade
resonances.

6.7 Dynamics
9 Resonances of structural support systems that are within the Contractor’s scope of
supply and that affect the rotor vibration amplitude shall not occur within the specified
operating speed range or the specified separation margins.
9 The Contractor shall communicate the existence of any undesirable running speeds in
the range from zero to trip speed. A list of all undesirable speeds from zero to trip shall
be submitted to the Company for its review and included in the instruction manual.
y The effects of other equipment in the train shall be included in the damped unbalanced
response analysis (that is, a train lateral analysis shall be performed). In particular, this
analysis should be considered for machinery trains with rigid couplings.
y For gas turbine-driven units, the Contractor shall ensure that a torsional vibration
analysis of the complete coupled train is carried out and shall be responsible for
directing any modifications necessary to meet the requirements of clauses 4.7.3.1
through 4.7.3.6 of API 616.
9 The torsional natural frequencies of the complete train shall be at least 10% above or
10% below any possible excitation frequency within the specified operating speed
range (from minimum to maximum continuous speed).
9 In addition to the torsional analyses required in clauses 4.7.3.2 through 4.7.3.5 of API
616, the Manufacturer shall perform a transient torsional vibration analysis for turbine
driven trains containing generators or helper/start motors, using a time-transient
analysis. The requirements of clauses 4.7.3.6.1 through 4.7.3.6.3 of API 616 shall be
followed.
­ High-speed balancing shall not be performed, due to the fact that rotors that require
high speed balancing to achieve vibration limits during test will likely require field
balancing.
9 The vibration criteria provided in ISO 7919-4 and ISO 10816-4 apply to industrial gas
turbine sets used in electrical and mechanical drive applications per API 616 covering
the power range above 1 MW and a speed range under load between 3000 RPM and
25000 RPM. Aeroderivative gas turbines (including gas turbines with dynamic
properties similar to those of aeroderivatives but not free power turbines) are excluded
from this vibration criteria.
­ On gas turbines for power generation, the gas turbine design should ensure the
absence of turbine-generator torsional modes of vibration close to 60Hz and 120Hz, or
50Hz and 100Hz, for 60Hz and 50Hz transmission systems respectively, to avoid
torsional interaction with the electrical transmission system due to network switching
and other events (e.g. faults, line switching, load rejection etc.).
­ On gas turbines for power generation, an analysis to identify potential torsional
subsynchronous resonance (SSR) conditions shall be undertaken by the Contractor
when the power plant is connected to a series capacitor-compensated transmission
system. Due to physical and economical limitations, components exposed to these
conditions cannot be manufactured to withstand such torsional stress at resonance
conditions. Protective and/or preventive measures must therefore be employed to limit
the SSR effects. Protective measures, like protection relays, and preventive measures
like static filter, active filter or excitation system damper shall be agreed between the
Company and the Contractor.
­ On gas turbines for power generation, an analysis to identify potential device
dependent subsynchronous oscillations (DDSO) shall be undertaken by the Contractor
when fast acting control loops are present on large power electronic devices such as
high-voltage dc (HVDC) converter stations or on GTG’s themselves. This phenomenon
is due to control interactions and is not a resonance phenomenon. Thus the solution is
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in proper tuning of the controls and or introduction of filtering and supplemental

damping controls.

6.8 Bearings and Bearing Housings

9 The Manufacturer shall provide their standard bearing design and include bearing
description in the proposal. Hydrodynamic radial and thrust bearings are preferred. It is
recognized, however, that certain classes of gas turbines are designed to use rolling
element bearings.
9 Bearings shall have sufficient ultimate load capability to withstand forces resulting from
failure of any turbine component that requires immediate shutdown (such as loss of a
blade or bucket) in order to prevent excessive secondary damage to the turbine.
9 Bearings shall be selected to meet an L10 rated life of 50,000 hours continuous
operation at ISO continuous rating conditions and 32,000 hours at maximum axial and
radial loads and rated speed. The basic rating L10 life shall be calculated in accordance
with ISO 281:2007.
9 Hydrodynamic thrust bearings shall be selected such that under any operating condition
the load does not exceed 50 % of the bearing manufacturer’s ultimate load rating at site
rated power.
9 Hydrodynamic thrust bearings and radial bearings shall be fitted with bearing metal
temperature sensors installed in accordance with API 670.

6.9 Lubrication & Control Oil System

­ Lube & control oil systems shall comply with API Std 614.
­ The Manufacturer should specify mineral lubricants available on the market of the
Country where the gas turbine is installed.
­ The same lube oil from a common supply system should be used for the gas turbine,
the driven equipment and the load gear.
­ The main oil pump should be gear-type, shaft-driven through an accessory load gear. A
100% duty AC electric motor driven pump shall be provided for start up and shutdown.
The lube system shall be designed to withstand both the main and stand-by pump
simultaneously operating.
­ An emergency DC pump shall be provided to ensure that oil is cooled down after shut
down. The UPS and battery system supplied by the Manufacturer shall feed the
emergency DC pump for the duration of the post lube cycle.
9 The minimum retention capacity shall be calculated based on 8 min of normal oil flow.
­ Lube oil duplex filter with transfer valve shall be provided.
­ The piping upstream and downstream the lube oil filters shall be stainless steel.
­ The oil cooler shall include 3x50% duty fans.
­ An oil/vapor separator skid, including an oil/vapor separator, extraction fan and drain
box, shall be provided.
­ The lubricant table shall indicate, for each equipment or lubricated area, the following
data:
o make and tag of the lubricant;
o physical and chemical characteristics sufficient to define the equivalency with other
makes (viscosity at 50°C, specific gravity, index of viscosity, etc.);
o filling quantity;
o expected yearly consumption according to the experience of the Manufacturer.
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6.10 Materials
™ Materials of construction shall be as per Manufacturer’s standard, provided that they
are suitable for the gas composition and operating and site environmental conditions
specified by the Company.
9 If the Company has specified, in MOD.MEC.TUR.001, the presence of hydrogen sulfide
in any fluid (Í), materials exposed to that fluid shall be selected in accordance with the
requirements of NACE MR0175.
­ Material selection for auxiliary equipment, piping and instrumentation shall be in
accordance with API Std 616, Company requirements set in MOD.MEC.TUR.001 (Í)
and suitable for the service and the site environmental conditions.
­ The Contractor shall specify within the bid all proposed materials, including
interconnecting pipework, and instrumentation.
­ The final material selection shall be subject to the Company approval.
­ All materials used shall be new and shall meet the requirements of the applicable
Codes and fabrication Standards.
­ Construction materials shall be identified according to ASTM-DIN Standard. Proprietary
or non-standard identification of materials shall be complemented by standard
identification.
­ Grey cast iron shall not be used.
­ Asbestos shall not be used in any part of the package.
­ Stainless steel shall be used for the lube and control oil piping.

6.11 Welding and NDE

­ Welding & Welders shall be qualified according to ASME IX or EN 287. Welding
Procedures (WPS) and Welding Procedure Qualification Records (PQR) shall be
submitted to COMPANY for approval, prior to commencement of welding.
­ The Welding inspection and Non Destructive Examination Plan shall be mutually
agreed by the Contractor and the Company.
­ Welding inspection for the purpose of acceptance shall be performed after any post
weld heat treatment. Radiographic, ultrasonic, magnetic particle and dye penetrant
examination shall be performed by operators having an internationally recognized
qualification according to the acceptance criteria mutually agreed.
­ The reference Standard for non destructive examination shall be ASME V.

7. ACCESSORIES
7.1 Starting and Helper Driver
­ A gas turbine may use for starting:
o a starting driver, disengaging once self-sustaining speed is reached, or
o a helper driver, that remains coupled during operation to provide supplementary
shaft power, or
o the electrical generator as a motor, in power applications, thus dispensing with a
dedicated starting driver.
­ Starting electrical motors shall comply with Company Specification
20167.EQP.ELE.FUN “Asynchronous Motors”.
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­ The electric variable speed drive, if present, shall conform to Company Specifications
20179.EQP.ELE.FUN “Medium and High Power Variable Speed Electric Drive” or
20178.EQP.ELE.FUN “Low Voltage Variable Speed Electric Drives”.
9 The Contractor shall supply any clutches, speed-changing gears, torque converters, or
other power transmission equipment, including controls required or specified for the
starting and helper drivers. Gears in continuous service shall be in accordance with API
613 and gears in intermittent service shall be in accordance with API 677.
9 Starting drivers and their associated power transmission equipment shall be sized for
acceleration of the gas turbine unit and for either extended operation at purge or
compressor cleaning cycles. Any starting driver not suitable for operation at speeds
corresponding to turbine trip speed shall disengage automatically and shut down at its
maximum allowable speed or trip speed, as applicable. Failure of the starting driver to
disengage or re-engagement during operation shall automatically shutdown the turbine.
y As a minimum, the driver shall be rated to supply 110% of the starting and acceleration
torque required by the gas turbine (and the driven equipment train for single-shaft
machines) throughout the specified ambient temperature range.
y A turning gear and/or ratchet device shall be furnished, if required to avoid rotor
deformation after a trip-out. For single-shaft turbines, the turning gear shall be sized to
turn the entire train.
­ Manually initiated turning of rotors shall also be possible for maintenance and alignment
checks.
™ The starting driver gear shall comply with API 613 and the helping driver gear with API
677.

7.2 Load Gear

™ The load gear, when required, shall be in accordance with API 613 and shall have a
minimum rating equal to the potential maximum power of the gas turbine under all
specified operating and ambient conditions.
­ The minimum gear service factor shall be as per Table 3 of API 613.
­ The load gear shall be equipped with a system that monitors vibration, axial
displacement, bearing temperature, oil pressure etc.

7.3 Couplings and Guards

™ Load couplings shall be dry flexible membrane or diaphragm type.
™ Main load couplings shall be sized for maximum transient torque, which is based on the
potential maximum power of the gas turbine plus the maximum applicable helper driver
turbine power output.
­ Spacers of shall be provided to allow maintenance on one end of an equipment of the
train without dismounting the nearby equipment.
­ Couplings shall conform to ISO 10441 or API Std 671.

7.4 Baseplate
™ The gas turbine and its auxiliaries shall be supported by a single steel baseplate,
included in the supply, whose stiffness shall be sufficient to safeguard the train
alignment and functionality.
­ The Contractor shall submit drawings and calculations of the proposed baseplate
design for Company approval, before commencement of fabrication.
­ The baseplate shall be designed to meet allowable stress and deflection considering
transportation, lifting and operating loads.
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­ Floor plates shall have drain holes (min 16mm dia) at low points to prevent the
accumulation of rainwater.
­ Anchor bolts for all equipment shall be supplied by the Contractor and they shall be
selected according to the site and operating conditions.
­ Equipment mounting pads shall be machined flat and parallel after welding to baseplate
supports. To prevent distortion, the machining of mounting pads shall be deferred until
welding on the support base in close proximity to the mounting pads has been
completed.
­ The baseplate shall have vertical jacking screws along the main longitudinal members
with maximum intervals not exceeding 1500 mm. Anchor bolts holes shall be located in
the same reinforced area as the jacking screws.
­ The baseplate shall be equipped with pad-type lifting eyes to accommodate a four point
lift so that the complete package, including all equipments and accessories, can be
lifted with a single hook.
­ Vertical lift should be assumed for the design of the pad-eyes.
­ All shims, sole-plates and leveling screws shall be included in the supply.

7.5 Instrumentation and Control

7.5.1 GAS TURBINE CONTROL AND PROTECTION SYSTEM
­ The gas turbine control and protection system (GTCPS) shall comprise, but shall not be
limited to:
o control system
o protection system
o electrical cabin control console (lights, switches, buttons, HMI operator station, etc.)
o CCR HMI operator station
o HMI engineering station
o DCS interface (hardwired and serial)
­ The GTCPS shall have a redundant configuration (CPU, I/O, power supply, etc). No
failure of one system element, no on-line change of cards/modules and no external
influences (short-circuit, wire break, noise) shall cause erroneous operation or
deterioration of any hardware or software system.
­ The gas turbine commands, set points and related feedbacks necessary for GT remote
start up, shutdown, load changes and operational mode selection shall be hardwired to
the plant DCS.
­ The GTCPS shall communicate in redundant way (redundant gateways and redundant
cable connection) with the plant DCS, to allow monitoring of the gas turbine from the
DCS operator stations. A complete set of signals as per the standard operation system
shall be made available as serial signals to the DCS.
­ The control system shall implement as a minimum the following functions:
o start-up/shut-down control;
o frequency/load control;
o turbine temperature (TIT) control;
o inlet guide vane position control;
o auxiliaries control (lube oil, power oil, fuel, starting device, turning device, etc.);
o equivalent operating hours (EOH) counting;
o first-out detection, sequence-of-events recording, archiving.
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­ The protection system shall be SIL3 fail-safe (de-energized to trip) type, to minimize the
number of trips that reduce the gas turbine availability and life.
­ The protection system shall implement as a minimum the following functions:
o speed monitoring;
o vibration monitoring (bearing housing and shaft);
o axial displacement monitoring;
o gas path temperature monitoring (turbine outlet temperature);
o flame monitoring;
o lube oil pressure monitoring;
o bearing temperature monitoring.
­ The GTCPS shall be synchronized with the plant DCS through a clock signal.
­ The GTCPS shall allow:
o automatic acceptance of load;
o regulation of speed or load in response to a signal from the central control room.
­ A selector switch shall located in the GT electrical cabin to:
o allow the GT to be started only from the GT electrical cabin;
o allow the GT to be started only from the central control room.
­ The control system shall limit the turbine inlet temperature to the maximum allowable
temperature, the latter being constant regardless of the ambient temperature.
9 Control systems shall allow a purge period of sufficient duration to permit the
displacement of the volume of the entire exhaust system (including the stack).
9 Governor systems shall prevent the gas turbine from tripping on overspeed when an
instantaneous loss of electric, hydraulic, or aerodynamic load occurs. A safe, controlled
shutdown may occur in the event of hydraulic or load loss for safety reasons.
9 The Contractor shall provide an integrated sensing, alarm, shutdown, and display
system for conditions that could result in damage to the gas turbine unit or could
shorten the life of the unit. Starting equipment shall be interlocked to prevent rotation of
the unit until conditions are safe for starting.
9 A shutdown may be normal or an emergency. Sequences for either shall be automatic.
o Normal shutdown shall follow an orderly, safe, step-by-step procedure based on the
requirements of the specific machinery and applications.
o Emergency shutdown may be manually activated or may occur as a result of the
operation of a protective device. The system shall cause the fuel shutoff valve to cut
off the fuel supply and shall limit speed to the trip value. Where practical, means
shall be provided to prevent restarting before corrective action has taken place.
o Consideration shall be given to the relationship between turbine controls and driven
equipment. Unless otherwise specified, automatic means shall be provided for
isolating, upon shutdown, the driven equipment from the system that it is supplying in
order to prevent motoring or reverse flow. Operation of venting systems, for the
release of stored energy, may also be necessary.
9 An overspeed trip protection shall operate at 105% of maximum continuous speed for
mechanical drive applications. Generator drive applications can have an overspeed trip
setting lower than 105% of maximum continuous speed. Multiple-shaft turbines shall
have individual overspeed trip protection for each shaft.
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7.5.2 MACHINE MONITORING SYSTEM

­ A machine monitoring system (MMS) shall be provided for on-line monitoring of the
health and performance of the gas turbine, its auxiliaries and the driven equipment. The
MMS will allow predictive maintenance, improving efficiency, minimizing machinery
stops, decreasing unscheduled shutdowns, and reducing downtime for maintenance
work and costs.
­ The MMS shall comply with API 670.
7.5.3 CONTINUOUS EMISSION MONITORING SYSTEM
­ When required by local regulations, and as per Company’s Project documentation (Í),
a CEMS shall be provided according to ISO 11042.
­ The CEMS shall monitor the following emissions: O2, CO, CO2, NOX, SO2, UHC, PM
and all other parameters necessary for measurement corrections.
­ The gas analyzer shall be housed in a walk-in enclosure, complete with HVAC.
7.5.4 INSTRUMENTATION
™ The instrumentation shall conform to Company Specification 20150.PKG.STA.FUN
“Instrumentation & Automation Plants Included in Rotary Machine Package”.
y The following detectors shall be supplied and calibrated in accordance with API 670:
o vibration and axial-position monitors;
o casing vibration transducers;
o casing vibration monitors.
o bearing temperature monitors.
­ All package instrumentation shall be wired to junction boxes at skid edges.

7.6 Electrical Equipment

­ Electrical motors shall conform to Company Specification 20167.EQP.ELE.FUN
“Asynchronous Motors”.
­ Electrical variable speed drives, if provided, shall conform to Company Specification
20179.EQP.ELE.FUN “Medium and High Power Variable Speed Electric Drive” or
20178.EQP.ELE.FUN “Low Voltage Variable Speed Electric Drives”.
­ Electrical equipment protection level shall be appropriate to the hazardous area
classification of the package installation.
­ Low voltage distribution panel and MCC shall conform to Company Specification
20161.EQP.ELE.FUN
­ UPS panel shall conform to Company Specification 20162.EQP.ELE.FUN
9 Power and control wiring within the confines of the baseplate shall be resistant to oil,
heat, moisture, and abrasion. Stranded connectors shall be used within the confines of
the baseplate and in other areas subject to vibration. Measurement and remote-control
panel wiring may be solid conductors. A high-temperature, oil-resistant thermoplastic
sheath shall be provided for wire insulation protection. Wiring shall be suitable for the
environment temperatures.
y Electrical materials including insulation shall be corrosion resistant and non-
hygroscopic insofar as is possible. Depending on the installation location, materials
shall be tropicalized according to Company Specification 05497.VAR.ELE.STD.
y Control, instrumentation, and power wiring (including temperature element leads) within
the limits of the baseplate shall be protected against damage by being installed in
metallic conduits or in mechanically protected areas or shall be suitably
sheathed/braided and properly bracketed to minimize vibration and isolated or shielded
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to prevent interference between voltage levels. Conduits may terminate (and in the
case of temperature element heads, shall terminate) with a flexible metallic conduit
long enough to permit access to the unit for maintenance without removal of the
conduit.
­ A cabin containing the electrical equipment (LV switchboard, DC/UPS w/ battery
modules, etc.) and the GT control & protection equipment (GTCPS modules, F&G
panel, FF panel, etc.) shall be supplied and positioned nearby the GT enclosure. The
electrical cabin shall have the same HVAC and fire protection facilities as the GT
enclosure and shall be in accordance with Company Specification
20220.PKG.ETI.SDS.

7.7 Piping
­ Auxiliary piping design, fabrication and inspection shall be in accordance with API 614.
For piping included in the gas turbine package, piping classes shall be Manufacturer’s
standard.
­ All piping and tubing connections to the equipment shall be flanged.
­ All vent and drain connections shall be flanged and shall be routed to the edge of the
baseplate.
­ All terminations up to and including 24” shall have flanges to ASME B16.5; flanges
greater than 24”shall be to ASME B16.47 Series A.
­ Gaskets shall conform to ASME B16.20/ASME B16.21.
­ All pipework shall be adequately supported and shall have sufficient flexibility to allow
for thermal expansion and contraction. Dissimilar metals shall have an effective
insulating barrier fitted in between the pipe and the steel support to avoid galvanic
corrosion.
­ Threaded connections shall not be used unless where permitted by Company
requirements (Í).
­ Flange faces shall be installed plumb with respect to horizontal and vertical planes. All
steel pipe and fittings shall be free of scale, rust, weld flux, oil, grease and other foreign
materials. Interior welds of flanges and fittings shall be ground and finished to provide
smooth and matching bores.
­ No backing strips or rings shall be used.
­ All equipment shall have provision for drainage and venting. The minimum size of
drain/vent pipework and valves shall be 3/4”.
­ All drains and vents to atmosphere shall be fitted with blind flanges.
­ Drain piping shall be separate from relief valve discharge piping and they normally are
collected in a common header and routed to the edge of baseplate.
­ Where a piping system is connected to another piping system or to equipment of higher
design rating, the higher design rating shall prevail for all piping components up to and
including the first block valve in the system of the lower rating.
­ Piping termination points shall be grouped and supported at the edge of the baseplate.
­ The main piping connections shall be agreed between the Company and the
Contractor.
­ Valves shall not be located on overhead pipe runs. Valves shall be preferably located
on horizontal pipe runs and, only when strictly necessary, on vertical pipe runs.
­ Threading of nuts and bolts shall be in accordance with ASME B1.1.
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7.8 Combustion Air Inlet and Exhaust Systems

7.8.1 INLET SYSTEM
9 The inlet system shall be designed for a maximum total pressure drop of 1 kPa (4 in.
water) with a clean air filter and at least 110 % of the air mass flow (including any
required ventilation air) at site rated power, ISO power or power at site minimum
temperature, whichever is greater.
9 Bolts, rivets, or other fasteners that can become loose and be carried in the air stream
shall not be used in the inlet system downstream of the final stage of filtration.
9 If required for safe operation (occurrence of temperatures between +5 °C and -5 °C and
relative humidity >80%), a duct mounted anti-icing system shall be provided. The
Contractor shall fully describe the system, Contractor’s scope, effect on gas turbine
performance over the ambient range, and required utilities.
™ The Company shall specify in the Project documentation the meteorological data
obtained by long-term measurements at site for the gas turbine Contractor to use in
selecting the inlet system components.(Í)
™ The Company shall specify in the Project documentation the air quality, indicating
chemical contaminants (see API 616 Section 5.6.1.9.1), and the presence, distance
and direction to major local or distant potential sources for contamination (see API 616
table 7), if any.(Í)
­ All components of the air inlet system shall be in 316L stainless steel.
­ The air intake system shall be made airtight employing continuous welding and
elastomeric sealant for bolted assemblies. Air tightness shall be durable.
y An under pressure protection device (e.g. implosion door) shall be provided to prevent
excessively high delta pressure in the turbine inlet in the event of filter icing, or
plugging. This device shall be instrumented to provide remote indication when the
device is actuated.
™ The Contractor shall select the type of inlet filtration required to meet site conditions
and operational requirements. Site conditions include the contaminants in the ambient
air from surrounding vegetation, weather events, local plant emissions, temporary
emissions (construction, roads, etc.), future emissions (if any) and seasonal changes.
­ The inlet filter system shall comprise:
o weather hoods;
o weather louvers;
o trash screen (birds, leaves, cardboard, bags and other objects);
o Insect screen, if necessary;
o anti-icing system , if necessary;
o inertial separator;
o moisture coalescer, if necessary;
o pre-filter;
o high efficiency filter, pulse-air self-cleaning type, if caking is not foreseen.
­ When the minimum ambient temperature is 5°C or lower, an ant-icing system shall be
provided. The ant-icing system should automatically start to warm the air entering the
inlet air filter when the ambient temperature drops to 5°C. The following solutions shall
be used to heat up the inlet air stream:
o mix-up with the compressor bleed air;
o exchange heat with the exhaust gas through a tubular heat exchanger (in 316L
stainless steel);
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o mix-up with the enclosure ventilation exhaust air.

­ Pulse filters shall not be used where the atmosphere may contain aerosols, soot and
dust. Pulse filters should not be installed in environments, e.g., offshore, where
humidity may cause the caking of dirt.
­ Reference is made to Section 13 “Special Requirements”, where further environmental
requirements are detailed.
™ Silencer attenuation shall meet the noise limitations of Section 4.3 “Noise Control”.
9 Silencers shall be of welded stainless steel and shall be flanged.
9 An acceptable inlet joint may be fabricated from a flexible material.
7.8.2 POWER AUGMENTATION DEVICES
9 If required, the evaporative cooler shall be supplied complete with cooler media,
circulation pump, sump drains, and corrosion resistant mist eliminator. The mist
eliminator shall minimize moisture carryover into the inlet air stream at 105% of
maximum engine mass flow and worst case ambient conditions (low temperature and
high humidity).
9 Water circulation shutoff shall be controlled with reference to turbine compressor inlet
temperature to eliminate any possibility of inlet icing caused by moisture from the
evaporative cooler. The minimum temperature is to be determined by the manufacturer,
taking all factors into consideration.
9 All evaporative cooler metallic housing and internal structural support shall be stainless
steel. Manways shall be provided for complete access both upstream and downstream
of the cooler media and mist eliminator sections. All piping shall be 300 series stainless
steel.
­ Absorption chillers (liquid-to-air heat exchangers) shall not be used, due to their high
operation and maintenance complexity.
­ If required, the fogging system (also known as wet compression), namely the
vaporization of water at the compressor inlet, shall be supplied as a complete package
(spray nozzles, water piping, water injection rack, pump skid etc.), managed by the
GTCPS.
7.8.3 EXHAUST SYSTEM
­ The exhaust stack height shall be selected with the following requirements:
o prevent recirculation of the exhaust gas into the combustion air intake, the ventilation
air intake, the air-cooler banks or the inlet of nearby process equipment;
o disperse exhaust gas avoiding excessive ground level concentrations (see Section
4.5 “Exhaust Stack”).
­ The Contractor shall provide evidence that the selected stack height meets the
dispersion and no-recirculation requirements.
­ The exhaust stack shall be complete with aircraft warning lights as per FAA AC
70/7460-1K, ladders and platforms.
­ The exhaust stack shall be thermally and acoustically insulated and internally lined with
stainless steel.
­ The exhaust stack shall be designed to prevent rain ingress into the gas turbine
exhaust collector.
y The exhaust system shall be designed for 1.5 kPa (6 in. water) pressure drop when
there is no heat recovery system. If a heat recovery system is specified, the system
pressure drop shall not exceed 2.5 kPa (10 in. water).
™ Silencer attenuation shall meet the noise limitations of Section 4.3 “Noise Control”.
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9 The exhaust expansion joints shall be of metal or high-temperature fabric. If fabric is

used, is shall be multilayered and reinforced with stainless steel wires. All bolting, duct,
and joint components in contact with the fabric shall have rounded edges to avoid
tearing of the material.
9 For exhaust temperatures greater than 455 °C (850 °F) at site rated power, special
precautions shall be exercised in the selection of duct materials to avoid carburization
or corrosion at these elevated temperatures.

7.9 Cooling Water System

­ The cooling water system, comprising the cooling water skid, the off-base water/air
cooler and the interconnecting piping and valves, shall provide cooling water to the
following consumers:
o lube oil storage skid
o the generator air coolers, when present
­ The cooling water shall be circulated by the main water cooling pump, located on the
cooling water skid, where a 100% duty backup pump shall be mounted.
­ The water/air cooler shall have 3x50% duty fans.

7.10 Compressor Blow-off System

­ A compressor blow-off system shall be provided to by-pass a portion of air from the
compressor through blow-off valves into the atmosphere or into the exhaust duct during
start-up and shutdown of the gas turbine to avoid a compressor surge and to reduce
the power consumption during start-up.

7.11 Compressor Washing System

™ Compressor cleaning facilities shall be provided for both on-line washing and off-line
crank soak washing.

7.12 Fuel and Fuel System

™ The Manufacturer shall confirm the suitability of the fuel(s) specified by the
Company(Í) for the fuel system proposed, and shall provide references of installations
using fuel(s) of a similar quality and composition with the same GT model and fuel
system. If the Manufacturer has no operating experience with the fuel(s) specified by
the Company, or if the gas fuel(s) have a heating value outside the range specified by
the Manufacturer, a combustion test shall be performed.
9 For the fuel specified, the Contractor shall state in the proposal the anticipated
maximum uninterrupted run time or duration of the fuel system and the hot-gas-path
parts.
™ The Contractor shall verify that the requirements set in Section 4.4 “Combustion
Emission Control” are complied with by the gas turbine operating on all the intended
fuels.
7.12.1 GASEOUS FUEL
y The Company will specify the composition of the gas (normal, alternate, or start-up) to
be supplied (Í). Composition of the gas should include analysis to hydrocarbons with
12 carbon atoms. Analysis should also include expected moisture (H2O) content. Gas
should be dry at the turbine fuel nozzles to prevent over-temperature damage to the
turbine due to burning condensate. The Manufacturer shall advise the Company if
heating is required to maintain the gas above the dew point.
y The contaminants likely to be found in fuel gas depend on the kind of gas involved,
such as natural gas, coke oven gas, water gas, producer gas, and refinery gas. The
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concentration of contaminants in the gas will be specified on the datasheets by the

Company. Some of the contaminants that are likely to be found include the following:
o tar, carbon black, and coke;
o water;
o solids;
o naphthalene and gas hydrates.
9 To alleviate a possibility of liquid contamination, the Manufacturer shall review both the
design and off-design operation of the fuel supply system. This review shall include
both the Manufacturer’s and the Company’s fuel supply systems.
™ If recommended by the Manufacturer, a coalescing filter shall be furnished by the
Contractor to reduce the potential for damage to the hot-gas-path components from
entrained liquids. It shall be sized to keep liquid contents in the fuel gas at or below the
maximum levels allowed by the gas turbine Manufacturer.
­ Gas fuel will be supplied at a pressure, temperature and hydrocarbon and water dew
points specified by the Manufacturer. The Manufacturer shall state the maximum
variation which can be accepted in composition, heating value, Wobbe index,
hydrocarbon and water dew points, and in pressure and temperature for the fuel
envisaged.
y The concentration of hydrogen sulphide, sulphur dioxide, sulfur trioxide, total sulfur,
alkali metals, chlorides, carbon monoxide, and carbon dioxide will be specified by the
Company (Í) so that proper precautions can be taken, if necessary, to prevent
elevated-temperature corrosion of turbine hot-gas-path components and ambient
temperature corrosion of fuel control valves and systems. Total sulfur content must also
be considered to protect heat-recovery equipment from corrosion.
y The lower heating value (LHV) of each gas will be specified. During operation, the
actual heating value should not differ from the specified value by more than plus or
minus 10%.
y For variations in LHV of more than 5%, rate of change, together with upper and lower
limits shall be specified by the Company because special equipment may be required
for proper fuel control.
7.12.2 LIQUID FUEL
­ Liquid fuel will be supplied at a pressure, temperature and quality specified by the
Manufacturer. However, when operation with locally available commercial fuel is
envisaged, the Manufacturer shall state the consequences, if any, of burning the fuel as
purchased on the gas turbine life and performance.
7.12.3 FUEL SYSTEM
y A shut-off valve shall be located outside the gas turbine enclosure or building limits, or
in a separately enclosed gas fuel package at the interface of the enclosure or building,
to automatically isolate the fuel supply to the gas turbine in the event of a dangerous
situation. The associated vent valve can be located either inside or outside the gas
turbine or gas fuel package to vent the section of the pipe between the shut-off valve
and the automatic fast acting shut-off valve. The shut-off and vent valves are in the
BOP scope and not in the gas turbine package scope. Where risk assessment
indicates there is the potential for loss of containment from high-speed rotating
equipment that could cause damage to the valves or rupture of the fuel supply pipe to
the gas turbine, the shutoff valve(s) outside the gas turbine package and the supply
pipe to the valves shall be located outside the zone where hazardous projectiles may
occur from a potential failure of rotating equipment to ensure fuel shutoff can be
achieved. Where the gas turbine package is located in a building, the risk assessment
shall consider if the valves shall be located outside the building to provide additional
isolation. The fuel shut-off and the vent valve(s) shall be operated automatically on a
gas turbine trip if:
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o a fire has been detected within the gas turbine fire protection area; or
o where risk assessment indicates that the cause of the trip may cause damage or
failure of the pipe between the valves and the gas turbine package, or damage to the
equipment on the gas turbine package, either leading to the uncontrolled lealso
known asge of fuel.
9 Where, due to the toxicity of the gas or where adequate dispersion cannot be assured
or where environmental considerations prohibit venting to atmosphere, the gas vents
may be piped to a low-pressure flare stack < 50 kPa, and additional precautions to
prevent gas entering the gas turbine shall be implemented.
9 Gas distribution piping and tubing shall be 316L stainless steel.
y An automatic shut-off valve shall be located outside the gas turbine package to
automatically isolate the fuel supply to the gas turbine in the event of a dangerous
situation. The shut-off valve is in the BOP scope and not in the gas turbine package
scope. Where risk assessment indicates there is the potential for loss of containment
from high-speed rotating equipment that could cause damage to the valves or rupture
of the fuel supply pipe to the gas turbine, the shut off valve(s) outside the gas turbine
package and the supply pipe to the valves shall be located outside the zone where
hazardous projectiles may occur from a potential failure of rotating equipment to ensure
fuel shutoff can be achieved. Where the gas turbine package is located in a building the
risk assessment shall consider if the valve shall be located outside the building to
provide additional isolation. The valve shall be operated automatically on a gas turbine
trip if:
o a fire has been detected within the gas turbine fire protection area; or
o where risk assessment indicates that the cause of the trip may cause damage or
failure of the pipe between the valves and the gas turbine package, or damage to the
equipment on the gas turbine package, either leading to the uncontrolled lealso
known asge of fuel.
9 Where forward and reverse purge/drain sequences are used during start-up, operation,
or shutdown, risk assessment shall be carried out taking into account all reasonably
foreseeable risks.
7.12.4 DUAL FUEL SYSTEMS
y If specified by the Company (Í), the gas turbine shall be provided with the necessary
equipment to permit normal (starting and continuous) operation on either of the fuels,
i.e., liquid/gas, liquid/liquid, or gas/gas. The dual fuel system shall provide the capability
of automatic transfer from either fuel source to the other fuel source while under full or
part load operation.
9 The dual fuel system shall provide smooth, bidirectional fuel transfer without shutdown
or interruption of load-carrying ability.
9 When operating on gas fuel, the liquid fuel lines, nozzles, manifolds, etc., shall be
automatically purged continuously to prevent plugging and coking.
9 It shall not be possible under any condition for the reverse flow of fuel to occur into any
other system where this may lead to danger. Where this may occur, additional safety
devices shall be fitted to prevent reverse flow. Appropriate precautions shall be taken to
ensure that liquid fuels cannot enter the gas fuel system where gas fuel is used to
purge the liquid fuel burners. Where only a single fuel can be fired at any one time,
interlocks shall be provided to ensure that the standby fuel system cannot operate or is
isolated. Where more than one fuel can be fired at any one time, it shall be assured that
excess energy input due to overfuelling cannot occur in the gas turbine.
7.12.5 EMISSION SUPPRESSION SYSTEM
™ If required to meet the local regulations, the combustion emission suppression system
shall be shall be proposed by the Contractor and approved by the Company with the
following order of preference:
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o DLE combustors;
o water or steam injection.
­ Selective catalytic reduction (SCR) is used as a secondary emission suppression
system and it is restricted to applications with a heat recovery system installed in the
exhaust.
™ The life reduction of hot gas path parts due to water injection shall be taken into
consideration, as well as the increased complexity of the demineralized water system.
The Contractor shall specify the required quantity and quality of injection water.
­ The Contractor shall describe in its proposal flame stability issues and the ensuing
operating limitations, if any, due to DLE combustors mode switch-over, also considering
the effect of high ambient temperature.

7.13 Painting and Coating

­ Painting and coating of equipment shall comply with Company Specification
20000.VAR.PAI.FUN “Protective Coating, Galvanizing and Metalizing for internal and
external Surfaces of Offshore and Onshore Structures and related Components”.
Manufacturer’s standard painting system may be proposed as an alternative, but shall
be subject to Company’s review and approval.

7.14 Enclosure
­ The enclosure shall be built for all-weather conditions, and it shall be designed to
simplify maintenance and provide acoustical and thermal insulation.
­ The enclosure shall be ventilated to extract the heat generated by the gas turbine and
its auxiliaries, and to dilute the concentration of flammable vapors that may accumulate
within the enclosure. When different compartments separate the enclosure, each shall
be ventilated.
­ The enclosure shall be ventilated with forced-draught (thus maintaining a pressure
above atmospheric pressure). When the surrounding area is classified, gas and smoke
detectors shall be installed at the ventilation air inlet, so that a unit emergency
shutdown can be initiated. Only when the surrounding area is safe, may induced-
draught configurations (indoor pressure below the atmospheric pressure) be proposed
by the Contractor and they shall be subject to the Company approval. 2x100% duty
ventilation fans shall be installed. Ventilation air shall be filtered.
­ Enclosure inlet vents shall be equipped with self-cleaning updraft filters to remove dust
and sand (especially in desert environments), although the risk formation of dust cake
shall be assessed. The exhaust vents shall equipped with back draft dampers to
prevent dust ingress when the unit is not running. For forced-draught designs,
ventilation air shall be taken from the inlet filter house downstream the filters.
­ Both the inlet and the outlet ventilation openings shall be equipped with a silencer.
­ The ventilation system shall be fully automatic and controlled by the gas turbine control
system.
­ The enclosure walls and roof shall be made of a structural steel frame and panels,
treated for sound attenuation and thermal insulation, removable for maintenance. The
access doors shall be industrial grade/self-closing type with panic bars. Penetration
elements for cabling and piping shall be provided.
­ The enclosure shall be equipped with an internal maintenance trolley rail.
­ A fire & gas detection system, suitable for the detection of vapor/gas from the fuels
system, shall be provided as per 20193.VAR.SAF.SDS “Selection of Sensors and Gas
and Fire Detection Criteria”. Flame detectors, compensated rate of heat rise fire
detectors, flammable gas detectors, smoke optical detectors, F&G control panel with
capability to test the detection system integrity shall be provided.
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­ A fixed total saturation fire extinguishing system shall be provided, using a clean agent
(e.g., Inergen), to prevent combustion without compromising the safety of any worker
present in the enclosure. CO2 as an extinguishing agent shall not be used, due to safety
hazards.
­ The extinguishing system shall be actuated:
o automatically (by the fire detection system),
o manually, with a push button in the electrical cabin,
o manually, with a mechanical switch on the outside of the enclosure.
­ A test valve shall be installed downstream of the release valves of each release
mechanism.
­ To ensure the safety of operation and maintenance personnel:
o alarm lights shall be provided on the outside of the enclosure and on the F&G control
panel to indicate: extinguishant system normal, extinguishant release and
extinguishant electrically isolated;
o acoustic and visual alarms shall be installed within the enclosure to signal
extinguishant release;
o a two-position switch shall be provided on the outside of the enclosure and on the
F&G control panel to inhibit or allow automatic release of the extinguishant;
o if the enclosure is entered by personnel without first inhibiting the automatic release
of extinguishant, an acoustic alarm will be fired and annunciated on the F&G control
panel.
­ Optical alarms for fire, gas and smoke in the plant shall be provided inside the
enclosure.
­ Internal lighting, emergency lighting, small power outlets and the grounding system
shall be provided.
­ Where required by the ambient conditions, the enclosure shall be complete with an anti-
condensation heating system.
­ Electrical and control equipment shall be housed in separate cabins, as per
20220.PKG.ETI.SDS “Prefabricated Cabins for Electric Machinery and Equipment”.

7.15 Thermal Insulation and Personal Protection

­ The insulation to minimize the loss of heat via the turbine housing into the environment
(causing an efficiency reduction) and to reduce the thermal stresses during transients
shall be provided.
™ Insulation for personnel protection shall be provided by the Contractor. Turbine casings
normally accessible during operation shall be insulated and jacketed or provided with
suitable lagging or guards so that no exposed surface in a personnel access area
exceeds a temperature of 60 °C. Jackets and insulation shall be designed so that
routine maintenance may take place without damage being done to the insulation.
9 Where the application of insulation is not practical or interferes with unit design or
operation, barrier isolation such as an enclosure may be utilized (with the approval of
the Company) to protect personnel from excessive temperature. These barriers must
be readily removable for ease of maintenance or fitted with suitable access points.
­ All protections and shielding shall be easily removable.
­ All connections to electrical transmitters shall protrude through the protection. Cables
shall be installed outside the protection.
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7.16 Earthing System

­ The package earthing system shall comply with Company Specification
06778.ICO.ELE.STD “Skid or Package Units - Typical Earthing Details”.
­ All electrical equipment supplied shall be bonded to the related skid.
­ Each skid shall be provided with two earthing bus bars for connecting to the main
earthing system.
­ All non-current carrying metalwork on the skid, which is not permanently welded to the
skid base, shall be bonded to the base using adequately sized earth cables.
­ Equipment anchor bolts shall not be used for earthing purposes.
­ All earthing connections shall be clearly identified on the General Arrangement
Drawings and the earthing terminals shall be in accordance with the International
Standards and Local Regulations.

7.17 Nameplates & Rotational Arrows

™ A nameplate shall be securely attached at a readily visible location and on:
o the gas turbine;
o the driven equipment;
o any major piece of auxiliary equipment.
9 Rotation arrows shall be cast in or attached to each major item of rotating equipment at
a readily visible location.
™ Nameplates and rotation arrows (if attached) shall be of 316 stainless steel and have
stamped or engraved lettering of 5 mm minimum height with wording in the English
language. Attachment pins shall be of the same material. Welding is not permitted.
™ The following data, as a minimum, shall be clearly stamped on the nameplate of the
gas turbine. Units used on the nameplates shall correspond to those used on the
datasheets:
o Project tag number;
o year of manufacture;
o Manufacturer’s name;
o serial number;
o model;
o site rated power and speed;
o site rated temperature;
o site rated inlet pressure;
o site rated exhaust pressure;
o site rated firing temperature;
o lateral critical speeds;
o maximum continuous speed;
o overspeed trips;
o fuel types.
­ The following data, as a minimum, shall be clearly stamped on the nameplate of any
major piece of auxiliary equipment:
o Project tag number, if any;
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o year of manufacture;
o Manufacturer’s name;
o serial number;
o model;
­ Nameplates shall be positioned to be clear of equipment surface or insulation by 40mm
and in such a way that they can be easily read, wherever possible from grade, adjacent
to a man-way or from an access platform.
­ Any additional information required by the Contractor or by the Company shall be
defined during the detail engineering phase.
­ The Contractor shall reference the Project equipment and instrumentation tag numbers
in its technical documentation. The Company will provide the tag numbers during the
detail engineering phase.

7.18 Special Tools

™ If special tools and fixtures are required to disassemble, assemble, or maintain the unit
(including any special lifting device), they shall be included in the quotation and
furnished as part of the initial supply of the machine. For multiple-unit installations, the
requirements for quantities of special tools and fixtures shall be mutually agreed upon
by the Company and the Contractor (Í). These or similar special tools shall be used
during shop assembly and post-test disassembly of the equipment.
­ The special tools shall be delivered in a lockable steel cabinet, together with the main
equipment.
­ The equipment “Installation, Operation and Maintenance Manual” shall include a list of
special tools and any special drawings or instruction on how to use such tools.

7.19 Spare Parts

­ The selection of spare parts, with the purpose of ensuring operation continuity, shall
take into consideration the following aspects:
o equipment criticality;
o mean time to failure (MTTF), for non-repairable items;
o mean operating time between failures (MTBF), for repairable items;
o mean down time (MDT, LDT, ADL), for repairable items
o ambient and service conditions
o plant operating life
­ The Contractor shall provide in the proposal the recommended spare parts split in the
following lists:
o start-up & commissioning spare parts, as firm proposal;
o 2-year operating spare parts, as option;
o capital spare parts, as option.
­ The Contractor shall submit in its proposal the Spare Parts Forms fully filled-in; each
item shall be priced separately.
­ After Contract Award, the Contractor shall submit the Company SPIL Forms.
­ All spare parts supplied by Contractor shall be new, wrapped and packed in such a way
as to be preserved in their original condition under normal operating conditions of
extended storage. These parts shall be tagged and coded so that later identification as
to intended usage can be made.
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­ Spare parts and relevant technical documentation are described in Company

Specification 20182.COO.GEN.SDS “Spare Parts”.
­ 2-year operation spare parts shall be selected in accordance with Company
Specification 05882.COO.MEC.PRG “2 Years Operation Spare Parts for Mechanical
Equipment and Machines”.
­ The Contractor shall describe in detail all maintenance activities for the first 36000
cumulated running hours (RH) or for the first five years. Optionally, Contractor shall
provide details of maintenance activities necessary for 8000 and 16000 RH subsequent
to the first 36000 cumulated RH or for the year six and year seven separately. The
submitted Maintenance Program shall include the hot path inspection, relevant
refurbishment at Contractor premises and major overhaul and list of people, material,
special tools if any, parts, devices, and any other consumable required.

7.20 Assembly Degree

­ The turbine package shall be shop assembled on the baseplate and other skids, if
applicable, or prefabricated to the maximum possible extent to minimize assembly at
site.
­ A preliminary alignment, baseplate drilling and coupling installations shall be done at
shop.
­ All auxiliary piping shall be completely assembled within skid limits and, if necessary,
prefabricated at shop and installed at site.
­ All the spools of the interconnecting piping shall be clearly identified.
­ Finish coats, where required, shall be applied at the workshop. Required insulation and
cladding shall be completed at the workshop.

8. OPERABILITY AND MAINTAINABILITY

­ The Contractor shall provide full details for maintaining the package. Due consideration
shall be given to the ease of access to all the items, during operation and maintenance,
when designing the layout of the package. Access shall be provided to all equipment
and any area requiring maintenance. The equipment shall be designed so that
maintenance can be carried out with the minimum special facilities/tools. All equipment
and piping shall be neatly arranged on the skid in such a way that they do not obstruct
maintenance operations. The Contractor shall work closely with the Company to ensure
that the most maintenance-effective layout is achieved for the package.
­ All major equipment items shall be supported on stainless steel shims at each mounting
point, to facilitate re-alignment at a later stage. No tapered shims are allowed. Sufficient
quantity of pre-cut shims shall be provided loose for site commissioning.
­ The Contractor shall provide in the proposal maintenance lifting requirements for the
equipment, and shall advise suitable methods (runway beam, overhead travelling
crane, etc.). The Contractor shall provide all the maintenance documentation (see
Section 12 “Contract Documentation”) and analysis necessary to manage the
maintenance activities and the data to populate the Company CMMS.

9. INSPECTIONS AND TESTS

9.1 General
­ Inspections & tests shall be in accordance with Company Specification
07423.PKG.GEN.SDS “Inspection and Test of Package Supplies”.
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9 Acceptance of shop tests does not constitute a waiver of requirements to meet field
performance under specified operations conditions, nor does inspection relieve the
Contractor of his responsibilities.

9.2 Inspections
y The Inspection & Test Plan shall be agreed between the Company and the Contractor
as to the type and extent of inspections and tests to be carried out on the supply. The
Company shall specify the type of inspections and the Company attendance in
MOD.MEC.TUR.101 “Gas Turbine Inspection & Test Data Sheets (IDS)”.(Í)
9 Positive material identification (PMI) test methods are intended to identify alloy
materials and are not intended to establish the exact conformance of a material to an
alloy specification. PMI is used to verify that the specified materials are used in the
manufacturing, fabrication and assembly of components.
9 Mill test reports, material composition certificates, visual stamps, or markings shall not
be considered as substitutes for PMI testing.
9 Unless specified otherwise by the Company or legislative requirements, non-destructive
examination (NDE) of materials shall be in accordance with ASME Section V and PED.

9.3 Tests
­ The Company shall specify the type of tests and the Company attendance in
MOD.MEC.TUR.101 “Gas Turbine Inspection & Test Data Sheets (IDS)”.(Í)
9.3.1 ROTOR OVERSPEED TEST
y The Manufacturer shall perform an overspeed test of the rotor at 120% of rated speed
for 2 minutes to demonstrate the mechanical integrity and vibration behavior of the
rotor.
9.3.2 MECHANICAL RUNNING TEST
­ The mechanical running test shall be executed in the shop on the gas turbine package
as a full-speed-no-load test. All equipment in the package shall take part in the test
(also known as string test), including auxiliary systems and couplings.
9 The acceptance criteria for vibration measured during the test shall be as per API 616
clause 4.7.5.2.1.
9 The acceptance criteria for vibration measured during commissioning shall be as per
API 616 clause 4.7.5.3.1.
9.3.3 PERFORMANCE TEST
9 The performance guarantees as per Section 11.2 shall be demonstrated at site
according to ISO 2314 or ASME PTC 22.
­ Exhaust emission guarantees as per Section 11.2 shall be demonstrated at site
according to ISO 11042
­ The Performance Test Procedure shall be submitted for approval by the Contractor to
the Company at least 2 months prior to the performance tests.
9.3.4 RELIABILITY TEST
­ The reliability of the gas turbine shall be demonstrated at site by running the gas turbine
for 72 consecutive hours without any failure, at the load required by the grid users or by
the driven machine. “Failure” is any fault causing the output power to be interrupted or
reduced.
­ In the event that the gas turbine is shut down for external causes during the test, the
test will be resumed and the running time cumulated until the total test duration is
attained.
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­ In the event that the gas turbine fails during the test, the Contractor shall perform a root
cause fault analysis (RCFA) and solve the problem. The test can fail maximum twice –
the third session being successful or the reliability shall be considered insufficient.

10. PRESERVATION, STORAGE, PACKING AND TRANSPORT

­ Preparation for shipment shall conform to Company Specification
20185.COO.GEN.SDS “Handling and Protection of Materials and Equipment”.
­ Packing shall comply with Company Specification 05883.VAR.GEN.SPC “Packing for
the Dispatching of Material and Equipments”.
­ As a minimum, the Contractor shall:
o prepare the supply for shipment and deliver to nominated delivery point;
o furnish internal and external shipping braces required to prevent damage or
movement during transportation;
o furnish all the crates with relevant Packing List and Shipping Documentation;
o provide shipping, installation, operation and maintenance weights and centre of
gravity;
­ The Contractor shall provide Storage and Maintenance Procedures for Company's
review and approval, which shall include, as a minimum, the following subjects:
o weather protection;
o equipment storage maintenance;
o periodical inspection;
o periodical maintenance;
o notice required for equipment usage;
o corrosion protection and application of temporary coatings;
o storage conditions including temperature range and humidity.
y When a spare rotor is purchased, the rotor shall be prepared for unheated indoor
storage for a period of at least three years. The rotor shall be treated with a rust
preventative and shall be housed in a vapor-barrier envelope with a low-release
volatile-corrosion inhibitor. The rotor shall be crated for domestic or export shipment, as
specified. A Company-approved resilient material 3.0 mm (1/8 in.) thick [not
tetrafluoroethylene (TFE) or polytetrafluoroethylene (PTFE)] shall be used between the
rotor and the crude at the support areas. The rotor shall not be supported at journals.
y The inspections indicated in MOD.MEC.TUR.101 “Gas Turbine Inspection & Test Data
Sheets (IDS)” shall be executed, with the indicated type of check.

11. WARRANTY AND GUARANTEES

11.1 Warranty
­ All equipment and component parts shall be warranted by the Contractor against
defective material, design, and workmanship for one year after being placed in service
(but not more than 18 months after date of shipment).
­ If any performance deficiencies or defect occur during the guarantee and warranty
period , the Contractor shall make any necessary alterations, repairs and replacements
free of charge, free on board factory. Field labor charges, if any shall be subject to
negotiation between the Company and the Contractor.
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11.2 Performance Guarantees

­ The following parameters shall be guaranteed at reference site ambient conditions
(temperature, rel. humidity, pressure, elevation), reference fuel gas composition and
base load setting:
o power output [kW]:
ƒ at generator terminals, when the driven equipment is an electrical generator;
ƒ at turbine shaft, when the driven equipment is a compressor or pump;
o heat rate [BTU/h/kW], with power output measured as above;
o sound pressure level at 1m from the equipment [db(A)].
­ The following combustion emissions shall be guaranteed, in compliance with the local
regulations:
o NOx [ppm vd] (oxides of nitrogen), 15% O2 dry basis, at reference site ambient
conditions, reference fuel gas composition and from 100% to 50% base load;
o CO [ppm vd] (carbon monoxide), 15% O2 dry basis, at reference site ambient
conditions, reference fuel gas composition and from 100% to 50% base load.
­ If required by the local regulations, the following additional combustion emissions shall
be guaranteed:
o UHC (unburned hydrocarbons);
o SOx (oxides of sulfur) and PM (particulate matter);
o CO2 (carbon dioxide).

12. CONTRACTOR’S DOCUMENTATION

12.1 Tender Documentation
­ The Company shall specify the technical documents to be provided by the Contractor
during the tendering phase in MOD.MEC.TUR.201 “Gas Turbine Required Document
Data Sheets (DDS)”.(Í).

12.2 Contract Documentation

­ The Company shall specify the technical documents to be provided by the Contractor
during the execution phase in MOD.MEC.TUR.201 “Gas Turbine Required Document
Data Sheets (DDS)”.(Í)
­ The Contractor shall prepare the as-built revision for each document (drawings,
specifications, procedures, data sheets etc.) modified during field installation.

13. SPECIAL REQUIREMENTS

13.1 Sour Gas Service
™ Gas turbine components in contact with gas containing H2S including trace quantities,
as well as the external bolting on the casing, shall comply with NACE MR0175.
™ Sour gas at high temperature may require that the fuel gas system be made of duplex
stainless steel.
™ H2S detectors shall be installed in the enclosure of gas turbines burning sour fuels.
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13.2 Coastal Installations

­ The gas turbine is in a “coastal environment” when it is installed on land and within
16km of the sea.
13.2.1 INLET AIR SYSTEM
­ The inlet air filtration system should have mist eliminators for water and salt removal
and high-efficiency filtration for salt removal.

13.3 Offshore and Marine Installations

­ The gas turbine is in an “offshore environment” when it is installed at sea, at an
elevation higher than 30.5m. A “marine environment” is an installation at sea, below
30.5m elevation.
13.3.1 VESSEL INSTALLATIONS
­ Gas turbine packages installed on vessels or floating platforms shall be capable of
withstanding the vessel movements and inclinations specified by the Company (Í)
while in operation.
­ The functionality and safety of the seal-oil and lube-oil systems shall not be jeopardized
by vessel/platform motions and inclinations.
­ The baseplate shall be designed to minimize weight but it shall be stiff enough not to
have adverse effects either on the train alignment or the train rotor dynamic behavior.
The manufacturer shall perform a static and dynamic structural analysis to demonstrate
the suitability of the baseplate design.
­ The baseplate shall be supported on a 3-point mount with gimbals, to isolate the train
from deck movements.
­ All connecting pipework shall be anchored to the baseplate to prevent misalignment
caused by vessel movements.
13.3.2 WEIGHT CONTROL
­ Among proposal documentation, an estimate of the CoG and the total installed weight
of each gas turbine skid and off-skid equipment shall be supplied, with an upper
tolerance of 10% or 10 kg, whichever is greater.
­ The Contractor shall implement a weight monitoring program as per Company
Specifications 20186.COO.GEN.SDS “Weight Control System” and
20187.COO.GEN.SDS “Weight Control System for Engineering”. The Company shall
be notified of any deviation of more than 10% or 10kg, whichever is greater, from the
weight estimate supplied in the proposal.
­ The Contractor shall verify the weight of all components and auxiliaries, after
fabrication/assembly in the Manufacturer’s workshop or after reception from Sub-
suppliers.
­ A General Arrangement Drawing shall be provided, showing the weight and centre of
gravity of each skid and interconnecting components (piping, valves etc.) that are part
of the gas turbine package, both dry and operating (including fluids and lubricants).
­ When all the weights and CoG’s of significant components have been verified, the
Contractor shall issue the final revision of the General Arrangement Drawing with
weights and CoG’s one month before shipment of the gas turbine package.
13.3.3 INLET AIR SYSTEM
­ For the inlet air system, instead of 316L stainless steel, alternative corrosion resistant
materials such as marine grade aluminum alloys may be used. If aluminum alloy is
proposed, the Contractor shall furnish proof of the corrosion resistance of the offered
grade in the marine environment.
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­ When selecting the inlet air filter system, the Contractor should take into consideration
the amount of salt depending on the wind speed and direction and the elevation of the
gas turbine.
­ The inlet air filtration system should be a low velocity type, comprising mist eliminators,
pre-filter/coalescer and high-efficiency filter - pulse-air self-cleaning filters should not be
used. Alternatively, a high velocity bag-filter may be employed, consisting of weather
hood or weather louver, high-efficiency bag filter and vane separator.

13.4 Desert Installations

­ The desert is classified as an area with dry and hot climate. Large amount of dust is
present and there is little vegetation. Sand storms are common.
13.4.1 EMISSIONS CONTROL
­ Combustion emission suppression systems based on water injection should not be
used, the preferred solution being DLE combustors.
13.4.2 ENCLOSURE
­ Enclosure inlet vents shall be equipped with self-cleaning updraft filters to remove dust
and sand. The exhaust vents shall equipped with back draft dampers to prevent dust
ingress when unit is not running.
­ Protections against dust and sand ingress shall be provided considering sand storms of
an intensity appropriate to the location.
­ Ventilation shall be forced-draught type (indoor pressure above atmospheric pressure).
Induced-draught ventilation shall not be used, due to the risk of sand and dust ingress
from lealso known asges in the enclosure.
­ Proper grounding of the enclosure shall be provided to account for the high electrostatic
charges due to particle impact during a sand storm.
13.4.3 INLET AIR SYSTEM
­ When selecting the inlet air filter system, the Contractor should take into consideration:
o Dust haze, dust low wind and dust storms
o Sand storms
o Fog and high humidity
o Moisture collection on filters that causes the formation of dust cake
­ The inlet air filter system should comprise a moisture coalescer and a high efficiency
filter, pulse-air self-cleaning type.

13.5 Arctic Installations

­ The arctic environment is characterized by freezing weather (below 0°C) for an
extended period of time.
13.5.1 MATERIALS
­ Low-carbon steels can be notch sensitive and susceptible to brittle fracture at ambient
or lower temperatures. Therefore, only fully killed, normalized steels made to fine-grain
practice are acceptable.
™ All pressure-containing components including nozzles, flanges, and weldments shall be
impact tested in accordance with the requirements of ASME Section VIII, (see Section
9.2 “Inspections”).
­ Differential expansion (contraction) shall be considered when designing the gas turbine
installation.
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13.5.2 ENCLOSURE
­ The enclosure shall be provided with a heating, air conditioning and ventilation
systems.
­ The design of the enclosure ventilation system shall consider a “cold soak” condition,
with the unit not operating and determine what components will require heating and to
what level to be able to start the unit. During operation, which components will continue
to require heating, how much radiated heat is available from the compressor, lube
system and driver.
­ The design of the control system of the enclosure ventilation shall allow for alteration of
the sequencing of operations due to the temperature and length of the lines involved.
­ Enclosure inlet ducting or any intake plenum abutting a heated space shall be
insulated.
­ For stand-by units, the enclosure ambient temperature may be required by Company to
be maintained notwithstanding the outdoor conditions (Î).
­ Provision shall be made for start-up from a “cold soak” condition by:
o selecting a suitable lube oil
o sizing the oil tank heater;
o pre-lubing or circulation of oil through the gas turbine;
­ Because of the 24-hour winter darkness, ample lighting shall be provided inside the
enclosure.
­ In the enclosure, sufficient room for personnel wearing bulky outer winter clothing to
move around equipment shall be provided. The enclosure shall also be equipped with a
vestibule with space to stow cold weather outer clothing.
13.5.3 OIL COOLER
­ The oil cooler, sized for full load operation at the highest summer ambient, shall be by-
passed in cold ambient temperatures. Care shall be taken in the system design so that
when the oil temperature rises to normal operating level a sudden oil by-pass shutoff is
prevented.
13.5.4 INLET AIR SYSTEM
­ When selecting the inlet air filter system, the Contractor should take into consideration
the ice build-up due to the ingestion of snow or freezing rain, or to the depression of
cool humid air in the inlet system. Other hazards to be avoided are ice ingestion and air
intake obstruction.
­ The inlet air filter system should comprise:
o Snow hoods
o High efficiency filter, pulse-air self-cleaning type
o Anti-icing system (re-circulated exhaust air or compressor bleed)
13.5.5 FUEL SYSTEM
­ Hazards of using low temperature gas fuel shall be taken into consideration when
selecting the components of the fuel system.

13.6 Tropical Installations

­ Tropical areas are characterized by hot climate, high humidity, monsoons, high winds
and insect swarms.
13.6.1 INLET AIR SYSTEM
­ When selecting the inlet air filter system, the Contractor should take into consideration:
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o Large amounts of rain

o High humidity
o Insects
o Pollen
o Salt in aerosol form, if location is near a shoreline
o Normally, low dust, even if construction site and unpaved roads can contribute to a
dusty environment
­ The inlet air filter system should comprise:
o Weather hoods
o Extended area insect screens
o Pre-filter, moisture coalescer, vane separators
o High-efficiency filter