EXCEL EXPLORATION & PRODUCTION:DETAILED

ENGINEERING DESIGN OF 2 X 20,000 BARRELS CRUDE

STORAGE TANK

Doc Title: SPECIFICATION FOR HI-LOW PILOT SWITCH

CODEFIDELITY TECHNICAL
SOLUTIONS

Doc. No.: Rev No.

CFTS-EXEP-INS-SPE-00000-02 R01 Page 1 of 15

SPECIFICATION FOR HI-LOW PILOT SWITCH

R01 12/10/2023 Issued for Review C.O K.O T.O

REV DATE DESCRIPTION PREP’D BY CHK’D BY APPROVAL

TABLE OF CONTENTS
 Rev No.
R01 Page 2 of 15

1 INTRODUCTION .................................................................................................................................................... 3

1.1 GENERAL ...................................................................................................................................................................... 3

1.2 PURPOSE OF DOCUMENT ............................................................................................................................................... 4
1.3 ORDER OF PRECEDENCE ............................................................................................................................................... 4
1.4 NIGERIAN NATIONAL STANDARDS (LEGISLATIVE/REGULATORY REQUIREMENTS) .................................................... 4
1.5 AMERICAN PETROLEUM INSTITUTE (API) ............................................................................................................... 4
1.6 AMERICAN NATIONAL STANDARD INSTITUTE (ANSI) ............................................................................................. 5
1.7 AMERICAN SOCIETY FOR TESTING & MATERIALS (ASTM) ..................................................................................... 6
1.8 AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) ..................................................................................... 6
1.9 NATIONAL ASSOCIATION OF CORROSION ENGINEERS (NACE) ................................................................................ 6
1.10 ABBREVIATIONS ...................................................................................................................................................... 7
1.11 REFERENCE DOCUMENTS .......................................................................................................................................... 8

2 UNITS .................................................................................................................................................................... 9

2.1 SITE CONDITIONS .................................................................................................................................................... 10

3 SCOPE OF THIS DOCUMENT: ........................................................................................................................... 11

4 STANDARDS & SPECIFICATIONS: .................................................................................................................. 11

5 SCOPE OF SUPPLY: .......................................................................................................................................... 11

6 HI-LOW PILOT SWITCH:.................................................................................................................................. 11

7 MATERIAL: .......................................................................................................................................................... 12

8 EQUIPMENT PROTECTION: ............................................................................................................................... 13

9 INSTALLATION REQUIREMENTS: .................................................................................................................... 13

10 CALIBRATION, INSPECTION & TESTING: .............................................................................................. 13

11 8.0 DOCUMENTATION: .................................................................................................................................. 13

12 TAGGING & NAMEPLATES: ........................................................................................................................... 14

13 VENDOR PRE-QUALIFICATION REQUIREMENTS:...................................................................................... 14

14 PREPARATION FOR SHIPMENT: .................................................................................................................. 14

15 RECEIPT & STORAGE: .................................................................................................................................. 14

 Rev No.
R01 Page 3 of 15

1 INTRODUCTION

1.1 General
Designated within the realm of the Federal Government of Nigeria
initiative and in alignment with the regulations set forth by the
petroleum (Amendment) Decree No. 23 of 1996, the Eremor field
emerges as one among the collection of twenty-four marginal fields
entrusted to indigenous companies engaged in oil exploration and
production. Excel Exploration and Production, a Nigerian Company
operating within the upstream domain of the oil and gas industry,
was granted ownership of this field. Nestled in the onshore swamp
expanse of Bayelsa state, specifically within Shell's OML 46 at
the South Forcados region, the Eremor field occupies a pivotal
position. It is positioned 4 kilometres to the north of the
Tunu/Kanbo field and approximately 70 kilometres to the south of
Warri. Encompassing a span of roughly 64.7 square kilometres, this
field remains a noteworthy presence in the area. Excel E&P Facility
is located at Eremor, near Ekeremor community in Ekeremor Local
Government Area of Bayelsa State, Nigeria.

Excel Exploration and Production Company Limited, the Client, seek

increase crude oil storage capability within the Eremor Facility.
Consequently 2 x 20,000 Barrels Crude Oil Storage tank is to be
built within the Eremor Facility.

CodeFidelity Technical Solutions has been contracted to carry out

the required detailed engineering design for the tanks.
 Rev No.
R01 Page 4 of 15

1.2 Purpose of Document

The purpose of this document is to outline General Specification
For Instruments that serves as a basis, guiding the engineering of
the 2 x 20,000 barrels storage tanks.

1.3 Order of Precedence

The following order of precedence shall be applied:

1. Nigerian National Standards (Legislative/Regulatory

requirements)

2. Chorus Energy Limited Specifications

3. International Standards

1.4 Nigerian National Standards (Legislative/Regulatory Requirements)

The Mineral Oils (Safety) Regulations of the Federal Republic of
Nigeria.

The Oil Pipelines Act (1990) Supplement to the Nigerian Oil and
Gas Pipelines Regulations (1995).

1.5 American Petroleum Institute (API)

API 5L Specification for Line Pipe

API 6D Specification for Pipeline Valves

API 12J Specification Oil & Gas Separators

API 14E Recommended practice for Design & Installation of

Offshore Production Platform piping systems.

API 14C Recommended practice for Analysis, Design,

Installation and Testing of Basic Surface Safety
system for Offshore Production Platforms.

API 520 Sizing, Selection and Installation of Pressure

Relieving Devices in Refineries

API 526 Flanged Steel Safety Relieving Valves.

 Rev No.
R01 Page 5 of 15

API 521 Guide for Pressure Relieving and Depressurization

Systems.

API 598 Valve Inspection and Testing

API 599 Metal Plug Valves—Flanged, Threaded and Welding

Ends

API 600 Steel Gate Valves - Flanged and Butt-welding

Ends, Bolted Bonnets.

API 602 Gate, Globe, and Check Valves for Sizes DN 100
(NPS 4) and Smaller for the Petroleum and Natural
Gas Industries.

API 607 Fire Test for Quarter-turn Valves and Valves

Equipped with Nonmetallic Seats.

API 609 Butterfly Valves: Double-flanged, Lug- and Wafer-

type.

API 650 Welded Tanks for Oil Storage

AP1 2000 Venting Atmospheric and Low-pressure Storage

Tanks

1.6 American National Standard Institute (ANSI)

ANSI B 16.5 Specification for Steel Pipe Flanges and Flanged
Fittings

ANSI B 16.9 Steel Butt Weld Fittings

ANSI B 16.25 Butt Welding Ends

ANSI B 31.3 Chemical Plants and Petroleum Refinery Piping

ANSI B 31.4 Pipeline Transmission Systems for Liquid

Hydrocarbons and Other Liquids
 Rev No.
R01 Page 6 of 15

1.7 American Society for Testing & Materials (ASTM)

ASTM A105 Carbon Steel Forgings for Piping Components

ASTM A106 Standard Specification for Seamless Carbon Steel

Pipe for High-Temperature Service

ASTM A333 Carbon Steel Forgings for Piping Components

ASTM A 193 Alloy Steel and Stainless Steel

1.8 American Society of Mechanical Engineers (ASME)

ASME VIII Boiler and Pressure Vessel Code

ASME SEC IX Welding Procedure and performance qualification

1.9 National Association of Corrosion Engineers (NACE)

MR-01-75 Sulphide Stress Cracking Resistant Metallic
Material for Oil Field Equipment
 Rev No.
R01 Page 7 of 15

1.10 Abbreviations
The Acronyms and abbreviations used within this document are
listed below:

Abbreviation Description

C & E Cause & Effect

ESD/ESDV Emergency Shutdown/ Emergency Shutdown

Valve

ft Feet/foot

F & G Fire & Gas

GA General Arrangement

I/O Input & Output

KBPD Thousand Barrel per day

MMSCFD Million Standard Cubic Feet per Day

MTO Material Take Off

PFD Process Flow Diagram

P&ID Piping and Instrumentation Diagram

PSIG Gauge Pressure in pound per square inch

ROW Right of Way

XCP Independent control panel

SDV Shutdown Valve

 Rev No.
R01 Page 8 of 15

1.11 Reference Documents

S/N Document Number Title

1. CFTS-EXEP-PRO-RPT-00000-01 SITE VSIST REPORT
2. CFTS-EXEP-PRO-RPT-00000-02 DESIGN BASIS
3. CFTS-EXEP-INS-PHI-00000-02 CONTROL & SAFEGUARDING PHILOSOPHY
4. CFTS-EXEP-PRO-DTL-00000-08 PIPING AND INSTRUMENTATION DIAGRAMS (P&IDS)
 Rev No.
R01 Page 9 of 15

2 UNITS

The units shown below (Customary/Imperial units in general) shall

be used as the main design units and all values quoted shall be in
these units. For clarity, alternative unit values are indicated in
the brackets only, after the design unit, when it is believed
desirable. The size of the unit shall be appropriate to the value
being measured.

Table 2-1: Units of Measurement

Description Unit

Nominal pipe diameters Inches (mm)

wall thickness Inches (mm)

Length ft (mm or m or km)

Area ft²(m2)

Liquid Volume ft³(m3)

Volumetric Oil Flow Rate MBPD

Standard Gas Volumetric MMSCFD (m3)

Flow Rate

Velocity ft/s (m/s)

Density lb/ft³(Kg/m3)

Pressure Psig (Barg)

Valve Size Inches (mm)

Viscosity cP
 Rev No. Page 10 of
R01 15

2.1 Site Conditions

Site conditions are assumed as shown below:

 Ambient Temperature Range 20 - 39°C

 Wind Velocity 0-80 mph

 Relative Humidity - Maximum 100%

 Rev No. Page 11 of
R01 15

3 SCOPE OF THIS DOCUMENT:

3.1 This specification describes the essential considerations in the

selection, installation, calibration, testing and commissioning of
Pneumatic Pressure switch

3.2 The Contractor shall be responsible for the selection of the

Pressure switch suitable forits intended application, its
procurement, packing, calibration, testing, and shipment to site,
installation and commissioning at site.

4 STANDARDS & SPECIFICATIONS:

4.1 Reference Specifications:

a) Specification No. 3.6: Instrumentation Design Criteria

b) Basic Bid Work

5 SCOPE OF SUPPLY:

5.1 The number of Pneumatic Pressure switch to be supplied and

installed shall be as per the requirements indicated in the Basic
Bid Work and the P & IDs.

5.2 The scope of supply shall also include commissioning spares and
two years’ spares as required by clause 3.6.4.8 of Instrumentation
Design Criteria, and as suggested by the Manufacturer.

6 HI-LOW PILOT SWITCH:

6.1 SWITCH TYPE:

• The pneumatic switch shall be block and bleed type.

6.2 GENERAL:
• Hi-Lo pilots (PSHL) used in well head instrumentation shall be
spring and piston type.
• For use elsewhere on the platform coil and tube type may be
considered.
• All shutdown and alarm switches shall be fail safe and abnormal
condition shall cause aloss in output signals for pneumatic
instruments

• Pressure gauge for supply, input and output shall be filled with
liquid for damping.
• Out put shall remain at 3.5 Kg/Cm2 between High and Low settings
and 0 otherwise.
• Process connection from bottom side, 316SS threaded ½” NPTF.
 Rev No. Page 12 of
R01 15

• The switch element shall be selected in such a way that it can

withstand an over-range pressure of 1.5 times maximum range
without loss of calibration.
• Connection for air or gas supply, transmission and control signals
shall normally be internally threaded ¼” NPT.
• Dead band shall be less than the difference between the normal
operating pressure and set point. Dead- band shall be fixed type
unless otherwise specified.
• The high and low-pressure ports shall be clearly marked on the
instrument.
• The switching mechanism shall have long life and minimum wear and
tear.
• In general compressed instrument air/gas will be used, as
pneumatic supply to instruments and vendor shall indicate
pneumatic supply pressure requirement.
• Pressure switches shall be field adjustable. Adjustments shall be
tamper proof.

7 Material:

• The material requirements for Pressure switch shall in general be

according to clause 3.6.4.5 of Instrumentation Design Criteria
and the material selection chart provided in Annexure I of this
specification.

• Instrument parts shall be resistant to the corrosive properties

of the process fluid and ambient conditions to which they are
exposed.

7.1 Accuracy:
• The maximum error shall not exceed 1% of the span. Repeatability
shall be ±1% for fixed dead band.

7.2 Reading Scales:

• Units for pressure switch shall be in kg/cm2

7.3 Enclosure Class:

• The Pressure switch shall be weather proof to NEMA 4X / IP 66

 Rev No. Page 13 of
R01 15

8 EQUIPMENT PROTECTION:

• Pressure switch protection requirements shall in general be as

per General specification for instrumentation.

9 INSTALLATION REQUIREMENTS:

• The installation of pressure switch shall in general be according

to General specification for instrumentation

• All pneumatic pressure instruments shall be mounted as close as

possible to sensing point.

• Mountings accessories required for Pressure Instrument shall be

316SS or better.

10 CALIBRATION, INSPECTION & TESTING:

10.1 Calibration, inspection and testing requirements shall in general

be as per General specification for instrumentation. In addition,
the following shall also be taken care of:

• Pneumatic Pressure switches shall be tested for set points. These

switches shall be calibrated using a hydraulic or dead weight
tester or precision pneumatic calibrator prior to installation.
A precision output meter, gauge or manometer shall be used to
monitor the output

• The manufacturer before shipment shall perform calibration and

alignment of all instruments.

11 8.0 DOCUMENTATION:

• The documentation requirements shall in general be according to

General specification for instrumentation

• Duly filled in data sheet shall be furnished along with the

purchase specification. A typical blank data sheet is provided as
Annexure II of this document
 Rev No. Page 14 of
R01 15

12 TAGGING & NAMEPLATES:

• Tagging & Nameplate requirements shall in general be according to

General specification for instrumentation

• The Pneumatic Pressure switches shall be provided with SS name

plate indicating the following:

1 Tag Number
2 Manufacturer’s Name and Model Number
3 Adjustable range
4 Element material
5 Enclosure classification
6 10.0 REVIEW & APPROVAL:

• Review and approval of purchase specifications and other related

documents shall in general be according to General specification
for instrumentation.

13 VENDOR PRE-QUALIFICATION REQUIREMENTS:

• The Vendor pre-qualification requirements shall in accordance to

General specification for instrumentation

14 PREPARATION FOR SHIPMENT:

• The Pneumatic pressure switch shall be prepared for shipment in

accordance to General specification for instrumentation
• .
15 RECEIPT & STORAGE:

• Receipt and storage of the pressure switch shall be in accordance

General specification for instrumentation.
 Rev No. Page 15 of
R01 15

ANNEXURE – I
Material Selection Chart for Pressure switch