PACO ®
Suggested Specifications
Type NCF, NCP, NCH
PUMPS Frame Mounted, Dry Pit Non- Clog Pumps
{ ENGI NEER’S NOTE: These specifications are intended to Testing: ( Option B) A (non-w itnessed, w itnessed) Hydraulic
allow you maximum flexibility throughout. I tems in bold Institute performance test shall be performed. The pump shall be
parentheses ( ) represent choices. I nappropriate choices tested at the design point as well as at least 4 other points to develop a
should be struck. Options should be selected as set of curves. Data shall be collected to plot the head-capacity curve in
required.} addition to the efficiency and brake horsepower.
SCOPE: The contractor shall furnish and install, as shown on the Performance & Design Requirements: The pumping unit shall be
plans and described in these specifications ( one, tw o, three, designed for the following operating conditions at maximum speed,
four) single stage, ( vertical, horizontal) Dry Pit Non-clog, unless otherwise noted:
frame mounted, end suction centrifugal pump unit(s) for Unit designation Pump No (_____)
wastewater pumping service. The pump(s) shall be (constant, Number of units (_____)
variable) speed and electric motor driven. The pump(s) shall be Primary Design Point
PACO model (NCP, NCF, NCH) or equal. Rated total head, feet (_____)
Capacity at rated head, GPM) (_____)
The pumping unit shall be complete with: Secondary Design Point
( Option A – Type NCP) pump, electric motor, motor pedestal, Rated total head, feet (_____)
intermediate shafting, guide bearings, pump pedestal, subbase, Capacity at rated head, GPM (_____)
suction elbow with cleanout opening. Operating head range, feet (_____)
( Option B – Type NCF) pump, electric motor, coupling, Max (nominal) pump operating
coupling guard, motor pedestal, pump pedestal, suction elbow speed at rated head, RPM (_____)
with cleanout opening. Max BHP required at input shaft of
( Option C – Type NCH) pump, electric motor, steel base plate, pump for any point in the operating
coupling, coupling guard, and all other appurtenances specified or head range (_____)
otherwise required for proper installation. Min pump efficiency at rated
head, feet (_____)
General: Equipment furnished and installed by the contractor Min available net positive suction head
under this section shall be fabricated, assembled, erected and at center line of suction elbow,
placed in proper operating condition in full conformity with feet absolute (_____)
drawings, specifications, engineering data, instructions, and Pump rotation as viewed from the
recommendations of the equipment manufacturer. Definition of driver end (_____)
terms and other hydraulic considerations shall be as set forth in Min pump nozzle size, inches
the Hydraulic Institute Standards. Suction (_____)
Discharge (_____)
Submittals: The data and specifications for each unit shall Min sphere diameter, inches (_____)
include, but shall not be limited to the following: Min hydrostatic test 1.5 x shutoff
head pressure, PSI plus suction press (_____)
Pumps:
Name of manufacturer Pump performance shall be stable and free from cavitation and noise
Type and model throughout the specified operating head range at design suction
Rotative speed submergences. The design performance shall be based on a wear ring
Size of suction nozzle axial clearance of not less than one mil per inch of wear ring diameter,
Size of discharge nozzle or 12 mils total, whichever is greater.
Net weight of pump
Complete performance curves showing capacity versus Materials:
head, NPSH required, pump efficiency and BHP
Casing, Casing Cast iron
Motors: Covers, and Frame ASTM A48
Name of manufacturer Case Wear Rings (Cast iron, 416 SS, Bronze, 300 SS)
Type and model Impeller (Cast iron, Bronze)
Type of bearing and lubrication Impeller Wear Rings (Cast iron, 416 SS, Bronze, 300 SS)
Rated size of motor, HP Shaft (Alloy steel, 316 SS)
Temperature rating Shaft Sleeve (Bronze, 316 SS, 416 SS)
Full load rotative speed Bearings ( Grease lubricated deep groove ball,
Net weight Angular Conact, Spherical Roller) –
Efficiency at full, ¾ and ½ load see Technical data sheet, D2a.6, pg.2 for
Full current load bearing types)
Locked rotor current Pedestal and Subbase Cast iron or fabricated steel
Stuffing Box Cast iron ASTM A48
Testing: ( Option A) Each pump shall be given an operational
test to check for mechanical integrity and leaks. All irregularities Packing: A minimum of 5 rings of graphite impregnated synthetic
will be corrected prior to shipment from the factory. packing, teflon split lantern ring and adjustable packing gland shall be
furnished as standard.
D2 Dry Pit Non Clogs
PC 52, 53, 49 Type NCF, NCP, NCH
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PACO ®
Suggested Specifications
Type NCF, NCP, NCH
PUMPS Frame Mounted, Dry Pit Non- Clog Pumps
Mechanical Seal: ( Option A) A double opposed inside type the lubricant. Suitable fittings shall be provided for properly adding
mechanical seal with BUNA-N elastomers, stainless steel lubricant.
hardware, ceramic stationary rings and carbon rotating rings shall
be provided. The frame shall provide ample clearance for stuffing box maintenance.
( Option B) An abrasive-resistant conical (ARC) type shaft seal
shall be provided. The rotating cone shall be of helical groove Bearings: Bearings shall be grease lubricated antifriction type.
design, and permit pumping of highly abrasive fluids or run dry Bearings shall have a minimum AFBMA L10 Life Rating of (_____)
conditions without damage or leakage. (Refer to D2a.6) hours at specified operating conditions. The pump
shaft speed shall not exceed the bearing manufacturer’s limitations.
Seal Pressurizer: ( Optional) To provide adequate lubrication
and maximum protection from abrasive particle contamination for Drive Unit: The pump shall be furnished with a ( vertical solid shaft,
the mechanical seals, a “Pressure-Miser” seal pressurizer shall be horizontal) squirrel-cage induction type motor rated _____ volts, ( 3,
provided. The seal pressurizer shall use light machine oil and 1) phase, ( 60, 50) Hertz, ( ODP, TEFC, Explosion proof) with
maintain a pressure at the sealing surface higher than the pump ( 1.15, 1.0) service factor. 40oC ambient. Motor shaft bearings shall
case pressure. be grease lubricated, antifriction type and regreaseable. Motor shall be
( Standard, Premium) efficiency with a minimum efficiency of
Pump Construction (_____).
Casing assembly: The casing assembly and drive connection Installation: The installation of the pumping equipment shall be in
shall permit the removal of the rotating element without accordance with the drawings and manufacturer’s instructions. All
disconnecting the piping. The discharge nozzle (and suction equipment shall be supported and securely anchored, making sure all
elbow) shall have flanged cleanout handlholes with interior connections are plumb and tight. All construction debris shall be
surfaces flush with the casing water passages. Casing parts shall removed from the system and wet well prior to operation of the
have registered fits to maintain alignment. The nozzle flanges pumping equipment.
shall be flat face with ANSI B16.1 Class 125 diameter and drilling.
A pipe tapped opening shall be provided for draining the stuffing Exposed Surfaces: All exposed surfaces shall first be cleaned by high
box leakage. pressure water or steam. Grease and oil shall be removed by suitable
solvent cleaner.
Pipe tapped openings shall be provided for draining, priming and
venting the casing. Immediately following surface preparation, the clean metal surface shall
be given a standard surface finished coat of air-dried alkyd resin type
Impeller: The impeller shall be a one-piece casting statically and enamel containing zinc chromate rust inhibitive pigment.
dynamically balanced. The interior water passages shall have
uniform sections, smooth surfaces, and be free from cracks and The completed coat shall have good adhesion and a high degree of
porosity. The impeller shall be securely locked to the shaft with resistance to moisture, alkalis and oils.
an acorn shaped capscrew, impeller washer, and locking washer
so it will not be loosened by reverse rotation, but it shall be Start- Up and Field Testing: Start-up and operational field tests shall
readily removable. be conducted by the pump manufacturer’s factory trained start-up
representative. The start-up and operational test shall be conducted in
The impeller shall be enclosed, non-clog type with at least two the presence of the engineer, owner operator personnel and the
ports, and capable of passing a _____ inch spherical solid. contractor. Final site specific level control adjustments shall be made to
ensure proper functioning of the system.
Shaft and Shaft Sleeves: The shaft shall be completely
machined. Deflection at the stuffing box shall not exceed .002”
at any head in the operating range.
The shaft shall be provided with a replaceable sleeve extending
from the impeller through the stuffing box. The sleeve shall be
positively secured to the shaft and shall be sealed with an O-ring
to prevent leakage between the shaft and sleeve. With sleeve in
place, total runout shall not exceed .002”.
Wear Rings: Renewable, L-shaped wear rings shall be provided
in the casing and on the impeller. The rings shall be positively
locked in place with set screws.
Bearing Frame Assembly: The bearing frame assembly shall
rigidly support the rotating element with two bearings. The
outboard bearing shall carry both axial and radial pump loads.
The assembly design shall permit axial adjustment of the rotor
without dismantling the pump. Bearing enclosures shall include
lip seals to prevent contamination of the bearings and to retain
D2 Dry Pit Non Clogs
PC 52, 53, 49 Type NCF, NCP, NCH
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