SynC™

SynC · SynC Standards

Horizontal Centrifugal Process Pumps

Rev1
IssuedOct 12, 2026
Contents

Revision history

Download
Build a datasheet from this standard Start a project with this standard already attached — one click, no setup.
Use in a project

1 Scope

1.1 Boundary of Work

NOTE This standard governs the pump as a unit of supply: the pump end from the suction connection through the discharge connection, the baseplate or mounting feet, the coupling and its guard, the shaft seal with the flush piping the manufacturer mounts, the wetted materials, the shop coating, and the tests that prove the unit on the factory stand and in the plant. (1.1.1)
NOTE This standard is read with Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, which carries the submittal register, the process equipment data sheet, unit responsibility, manufacturer qualification floors, the factory test witnessing policy, manufacturer's field services, nameplates, the pad, anchorage, and grout basis, vibration and airborne noise acceptance, lubrication first fills, delivery and storage, warranty administration, and the spare parts basis; none of those provisions is restated here. (1.1.2)
NOTE The standard reaches past the pump into the three execution activities that decide whether a pump that met its curve on the test stand meets it in the plant: the suction piping arrangement immediately upstream of the pump, the setting and grouting of the baseplate, and the coupling alignment. (1.1.3)
NOTE Work outside this boundary is governed by the standards named below, and this standard defers to them rather than restating their requirements: (1.1.4)
  • The motor as a product, its efficiency, insulation, bearings, and testing: Electric MotorsCommon Motor Requirements for Electrical EquipmentResolves to the current adopted revision.sync/electric-motors
  • Variable frequency drives, including drive programming and output filtering: Low Voltage Variable Frequency DrivesLow-Voltage Variable Frequency DrivesResolves to the current adopted revision.sync/low-voltage-variable-frequency-drives
  • Individually enclosed starters and motor control centers: Combination Motor StartersCombination and Manual Motor StartersResolves to the current adopted revision.sync/combination-motor-starters and Motor Control CentersMotor Control CentersResolves to the current adopted revision.sync/motor-control-centers
  • Housekeeping pads, anchor rods, post-installed anchors, non-shrink grout, and grouted base plates: Concrete PadsConcrete Equipment PadsResolves to the current adopted revision.sync/concrete-pads, Structural Steel Anchor BoltsAnchor Rods and Embedded SteelResolves to the current adopted revision.sync/structural-steel-anchor-bolts, Post Installed AnchorsPost-Installed Concrete and Masonry AnchorsResolves to the current adopted revision.sync/post-installed-anchors, Non Shrink GroutNon-Shrink GroutResolves to the current adopted revision.sync/non-shrink-grout, and Grouted Base PlatesGrouted Column Base Plates and Bearing PlatesResolves to the current adopted revision.sync/grouted-base-plates
  • Vibration isolators, inertia bases, and seismic restraint design: Vibration Isolation And Seismic RestraintVibration Isolation and Seismic RestraintResolves to the current adopted revision.sync/vibration-isolation-and-seismic-restraint
  • Pressure, flow, and other field instruments on and around the pump: Pressure InstrumentationPressure InstrumentationResolves to the current adopted revision.sync/pressure-instrumentation, Flow MeasurementFlow MeasurementResolves to the current adopted revision.sync/flow-measurement, and Process InstrumentationProcess InstrumentationResolves to the current adopted revision.sync/process-instrumentation
  • Control panels furnished with the pump: Industrial Control PanelsIndustrial Control PanelsResolves to the current adopted revision.sync/industrial-control-panels
  • The suction and discharge piping, its supports, and its pressure test: Ductile Iron Process PipingDuctile Iron Process PipingResolves to the current adopted revision.sync/ductile-iron-process-piping, Steel And Stainless Process PipingSteel and Stainless Steel Process PipingResolves to the current adopted revision.sync/steel-and-stainless-process-piping, and Plastic Process PipingPlastic Process PipingResolves to the current adopted revision.sync/plastic-process-piping
  • The check valve and the isolation valve on each pump discharge: Process Check ValvesProcess Check ValvesResolves to the current adopted revision.sync/process-check-valves, Resilient Seated Gate ValvesResilient-Seated Gate ValvesResolves to the current adopted revision.sync/resilient-seated-gate-valves, Eccentric Plug ValvesEccentric Plug ValvesResolves to the current adopted revision.sync/eccentric-plug-valves, and Butterfly ValvesButterfly ValvesResolves to the current adopted revision.sync/butterfly-valves
  • The wet well, clearwell, or dry pit the pump serves: Water Retaining Concrete StructuresWater-Retaining Concrete StructuresResolves to the current adopted revision.sync/water-retaining-concrete-structures
  • Field-applied finish coat systems over the shop coating: High Performance CoatingsHigh-Performance CoatingsResolves to the current adopted revision.sync/high-performance-coatings
NOTE The seal water or flush supply that a packed box or an externally flushed seal consumes is piped under the process piping standards, and where the supply is plant potable water it is protected under the plumbing standards; this standard states the pressure and flow the pump manufacturer requires at the connection and nothing about the supply beyond it. (1.1.5)
NOTE Intake and sump geometry are designed by the Engineer of Record under ANSI/HI 9.8 and shown on the drawings; this standard requires the pump manufacturer to review that geometry against ANSI/HI 9.8 for the pump furnished and does not design it. (1.1.6)

1.2 Pump Family Boundaries

NOTE This standard is the horizontal clean-liquid member of the process pump family, and the family is divided by the liquid and the pump arrangement rather than by the building the pump sits in: (1.2.1)
  • Solids-handling wastewater pumps in every arrangement, submersible in a wet well, dry-pit submersible with an immersible motor, and self-priming solids-handling, including chopper pumps and screw-centrifugal impellers, for raw sewage, primary and secondary effluent, return and waste activated sludge, and plant drain: Submersible Solids Handling PumpsSubmersible Solids-Handling PumpsResolves to the current adopted revision.sync/submersible-solids-handling-pumps
  • Line-shaft vertical turbine pumps in wet pits, cans, barrels, and deep wells, and submersible well pumps with submersible motors: Vertical Turbine PumpsVertical Turbine PumpsResolves to the current adopted revision.sync/vertical-turbine-pumps
  • Progressive cavity, rotary lobe, plunger and piston, peristaltic hose, and air-operated double-diaphragm pumps for sludge, scum, grit slurry, and thickened solids, with the discharge relief a positive displacement pump requires: Positive Displacement PumpsPositive Displacement PumpsResolves to the current adopted revision.sync/positive-displacement-pumps
NOTE A self-priming pump is placed by its liquid: a self-priming pump on clean water, service water, or washwater is this standard, and a self-priming solids-handling pump on sewage or plant drain is Submersible Solids Handling PumpsSubmersible Solids-Handling PumpsResolves to the current adopted revision.sync/submersible-solids-handling-pumps. (1.2.2)
NOTE A plant influent or effluent pump station built in a water-retaining structure with individually specified pumps is this family; a factory-assembled station delivered with its own basin, pumps, valves, and panel is Packaged Pump StationsPackaged Pump and Lift StationsResolves to the current adopted revision.sync/packaged-pump-stations, whatever its size. (1.2.3)
NOTE Building pumps stay with the building standards that own them, and a pump room in a treatment plant does not move them: hydronic pumps under HVAC PumpsHVAC PumpsResolves to the current adopted revision.sync/hvac-pumps, which also keeps the cooling tower vertical turbine pumps it claims, plumbing circulators under Plumbing PumpsPlumbing PumpsResolves to the current adopted revision.sync/plumbing-pumps, potable booster systems under Domestic Water Booster PumpsDomestic Water Booster Pump SystemsResolves to the current adopted revision.sync/domestic-water-booster-pumps, fire pumps under Fire PumpsFire PumpsResolves to the current adopted revision.sync/fire-pumps, and building sumps, ejectors, and grinders under Sump And Sewage PumpsSump and Sewage PumpsResolves to the current adopted revision.sync/sump-and-sewage-pumps. (1.2.4)
NOTE Chemical metering pumps belong to a chemical feed systems standard that is not yet owned by a SynC standard; an ASME B73.1 chemical process pump that transfers a chemical solution between tanks is this standard. (1.2.5)

1.3 Terms Used in This Standard

NOTE The following terms carry their Hydraulic Institute meanings throughout this standard: (1.3.1)
  • Rated point: the flow and total dynamic head the pump is selected to deliver, as scheduled on the pump schedule
  • Best efficiency point, BEP: the flow at which the pump reaches its highest efficiency at the furnished impeller diameter and rated speed
  • Preferred operating region, POR, and allowable operating region, AOR: the flow bands defined in ANSI/HI 9.6.3 relative to BEP flow for the specific speed of the pump
  • NPSH required, NPSHr, and NPSH3: the suction head above vapor pressure at which the pump suffers a 3 percent loss of head, published by the manufacturer as a function of flow
  • NPSH available, NPSHa: the suction head above vapor pressure the system delivers to the pump suction, calculated by the Engineer of Record and stated on the pump schedule
  • Suction energy: the product of inlet tip speed, NPSHr, specific gravity, and the suction specific speed gas-handling term, by which ANSI/HI 9.6.1 classifies a pump as low, high, or very high suction energy
  • Runout: the highest flow the pump can reach on the system head curve with every valve open and the discharge pressure at its lowest
  • Shutoff head: the total dynamic head at zero flow at the rated speed and furnished impeller diameter

2 Referenced Standards

2.1 Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2 Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
Standard Title
ANSI/HI 1.1-1.2 Rotodynamic Centrifugal Pumps for Nomenclature and Definitions
ANSI/HI 1.3 Rotodynamic Centrifugal Pumps for Design and Application
ANSI/HI 1.4 Rotodynamic Centrifugal Pumps for Manuals Describing Installation, Operation, and Maintenance
ANSI/HI 9.6.1 Rotodynamic Pumps Guideline for NPSH Margin
ANSI/HI 9.6.3 Rotodynamic Pumps Guideline for Operating Regions
ANSI/HI 9.6.4 Rotodynamic Pumps for Vibration Measurements and Allowable Values
ANSI/HI 9.6.6 Rotodynamic Pumps for Pump Piping
ANSI/HI 9.8 Rotodynamic Pumps for Pump Intake Design
ANSI/HI 14.6 Rotodynamic Pumps for Hydraulic Performance Acceptance Tests
ANSI/HI 40.6 Methods for Rotodynamic Pump Efficiency Testing
ASME B73.1 Specification for Horizontal End Suction Centrifugal Pumps for Chemical Process
API 682 Pumps, Shaft Sealing Systems for Centrifugal and Rotary Pumps
10 CFR Part 431 Energy Efficiency Program for Certain Commercial and Industrial Equipment (Subpart Y, Pumps)
NEMA MG 1 Motors and Generators
NFPA 70 National Electrical Code (Article 430)
ASME B16.1 Gray Iron Pipe Flanges and Flanged Fittings (Classes 25, 125, and 250)
ASME B16.5 Pipe Flanges and Flanged Fittings, NPS 1/2 Through NPS 24
ASME B16.42 Ductile Iron Pipe Flanges and Flanged Fittings (Classes 150 and 300)
ASTM A48/A48M Gray Iron Castings
ASTM A536 Ductile Iron Castings
ASTM A743/A743M Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application
ASTM A890/A890M Castings, Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex (Austenitic/Ferritic) for General Application
ASTM A276/A276M Stainless Steel Bars and Shapes
ASTM A564/A564M Hot-Rolled and Cold-Finished Age-Hardening Stainless Steel Bars and Shapes
ASTM B584 Copper Alloy Sand Castings for General Applications
ASTM B505/B505M Copper Alloy Continuous Castings
NSF/ANSI/CAN 61 Drinking Water System Components, Health Effects
NSF/ANSI/CAN 372 Drinking Water System Components, Lead Content
ISO 21940-11 Mechanical Vibration, Rotor Balancing, Part 11: Procedures and Tolerances for Rotors with Rigid Behaviour
SSPC-SP 10/NACE No. 2 Near-White Metal Blast Cleaning
SSPC-PA 2 Procedure for Determining Conformance to Dry Coating Thickness Requirements
29 CFR 1910.219 Mechanical Power-Transmission Apparatus

3 Submittals

3.1 Action Submittals

3.1.1 The Contractor shall submit the following for each pump, in addition to the submittals Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process requires, before the pump is released for fabrication:
  • Certified performance curve at the furnished impeller diameter and the rated speed, plotted from shutoff to runout, showing head, efficiency, brake horsepower, NPSH3, and the minimum continuous stable flow, with the rated point, the BEP, and the POR and AOR limits marked
  • Selection report stating the rated flow and head, the furnished and maximum catalog impeller diameters, the efficiency and brake horsepower at the rated point, the rated flow as a percentage of BEP flow, the shutoff head, the NPSH margin ratio and margin in feet at the rated point and at runout, and the suction energy classification
  • System head curves for each pump service, as overlaid by the pump manufacturer on the certified curve, with the single-pump, parallel, and runout points marked
  • Materials of construction for the casing, impeller, wear rings, shaft, shaft sleeve, seal chamber, gland, and fasteners, with the NSF/ANSI/CAN 61 and 372 certifications where the liquid is finished or potable water
  • Shaft seal data identifying the seal type, the API 682 flush plan, the face materials and elastomers, the seal chamber pressure and temperature limits, and the flush or seal water pressure and flow required at the connection
  • Bearing data stating the bearing type, the lubrication, and the calculated L10 rating life at the rated point and at the ends of the allowable operating region
  • Baseplate drawing showing the anchor bolt pattern, the grout holes and vents, the drip rim and drain, the leveling provisions, and the grout the manufacturer requires
  • Coupling data including the type, the spacer length, the service factor, and the manufacturer's published alignment tolerance
  • Shop coating and lining product data with the surface preparation and the dry film thickness
  • Factory test procedures for the hydrostatic, performance, and NPSH tests, with the test instrumentation and its calibration
  • The pump manufacturer's review of the intake or sump drawings against ANSI/HI 9.8, where the pump takes suction from a wet well, clearwell, or sump
Pump Action Submittals Requiredcheckbox
☑ Certified performance curve with POR and AOR marked
☑ Selection report with trim, percent of BEP, and NPSH margin
☑ System head curves overlaid on the certified curve
☑ Materials of construction with drinking water certifications
☑ Shaft seal data with the flush plan and seal water demand
☑ Bearing data with L10 life at the rated point and the AOR limits
☑ Baseplate drawing with anchor pattern, grout holes, and drip rim
☑ Coupling data with alignment tolerance
☑ Shop coating and lining product data
☐ Factory test procedures
☐ Manufacturer's ANSI/HI 9.8 intake review
NOTE The selection report carries more information per page than any other submittal for the pump: the rated flow as a percentage of BEP flow, the trim of the impeller against the maximum catalog diameter, and the brake horsepower at runout together predict most of what will go wrong with the pump over its life. (3.1.2)

3.2 Closeout Submittals

3.2.1 The Contractor shall submit the following for each pump, in addition to the closeout submittals Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process requires, before the pump is accepted:
  • As-built record for each pump stating the serial number, the installed impeller diameter read from the nameplate or measured, the motor serial number, and the seal and bearing part numbers
  • Certified factory test reports for the hydrostatic, performance, and NPSH tests
  • Field startup report recording the measured suction and discharge pressures, the calculated total dynamic head, the measured flow, the motor voltage, current, and speed, and the corresponding point plotted on the certified curve
  • Coupling alignment record showing the cold readings, the thermal offset applied, and the readings taken after thermal stabilization
  • Seal and packing record stating the flush or seal water pressure and flow measured at the connection and, for packing, the leakage rate set at startup
Pump Closeout Submittals Requiredcheckbox
☑ As-built record with installed impeller diameter
☑ Certified factory test reports
☑ Field startup report plotted on the certified curve
☑ Coupling alignment record, cold and thermally stabilized
☑ Seal and packing record with measured flush supply
3.2.2 The installed impeller diameter shall be recorded from the pump nameplate or by direct measurement, not copied from the submitted selection.
NOTE An impeller trimmed at the factory to a diameter other than the one submitted invalidates every later comparison against the certified curve, and the record made at closeout is what lets an operator decide years later whether the pump has worn or was never the pump on the schedule. (3.2.3)

4 Quality Assurance

4.1 Pump Manufacturer Qualifications

4.1.1 The pump manufacturer shall have continuously produced horizontal centrifugal pumps of the configuration furnished for not less than the period indicated in the datasheet, which applies in place of the experience term in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process where it is longer.
Manufacturer Experience with the Configurationrange
years
3510152025
Default: Not less than 10 years
4.1.2 The pump manufacturer shall operate a test facility capable of running each pump furnished at its rated speed through the full range of the certified curve, with instrumentation calibrated under ANSI/HI 14.6, and shall identify the facility in the factory test procedure.
NOTE Ten years is the term most water and wastewater pump specifications carry for a horizontal centrifugal pump, and the established manufacturers of the configurations this standard covers clear it without comment. A shorter term admits a manufacturer newer to the configuration, which can be the better product on an unusual duty, and a longer term adds nothing on a product line that has been built for decades. (4.1.3)

4.2 Drinking Water Contact

4.2.1 Every wetted component of a pump in finished water, potable water, or other drinking water service, including the casing, impeller, wear rings, shaft sleeve, seal faces and elastomers, gaskets, and interior lining, shall carry the NSF/ANSI/CAN 61 and NSF/ANSI/CAN 372 certifications required under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process.
4.2.2 Bronze and other copper alloys in drinking water service shall be of a lead-free alloy certified under NSF/ANSI/CAN 372, and the alloy designation shall be stated in the materials of construction submittal.
NOTE The traditional leaded bronzes a pump foundry pours for raw and service water do not meet the lead content limit, and the lead-free alloys that replace them in drinking water service are a different casting with different machining and a different price, which is why the alloy is named in the submittal rather than assumed from the word bronze. (4.2.3)

4.3 Pre-Installation Conference

4.3.1 At the pre-installation conference convened under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, the agenda for the pumps shall additionally cover the suction piping arrangement against the approved drawings, the baseplate leveling and grouting sequence, the alignment method and tolerance, the seal or packing flush supply, and the sequence of the factory and field tests.

5 Service Conditions

5.1 Pumped Liquid

5.1.1 The liquid each pump handles shall be as indicated in the datasheet, and every wetted component shall be selected for that liquid at its temperature and chemistry.
Pumped Liquidselect
Raw water
Finished or potable water
Service, seal, or utility water, non-potable
Plant washwater or reclaimed water
Clean process transfer liquid
Chemical solution or corrosive process liquid
Per drawings — the process and instrumentation diagrams and the pump schedule (deferred by default)
5.1.2 The liquid specific gravity used for the selection and the motor sizing shall be as indicated in the datasheet.
Liquid Specific Gravityrange
0.80.911.11.21.31.51.82
5.1.3 The pump and every wetted component shall be rated for continuous operation at the liquid temperature indicated in the datasheet.
Liquid Temperaturerange
°F
32406080100120140180212250
Per drawings — the pump schedule (deferred by default)
5.1.4 The suspended solids the pump will see shall be as indicated in the datasheet, and the impeller type, wear ring materials, seal faces, and flush plan shall be selected for them.
Suspended Solids in the Pumped Liquidradio
○ Clean liquid, no abrasive solids
○ Light suspended solids or silt
○ Abrasive solids such as sand or grit
NOTE A clean liquid admits the full range of enclosed impellers, soft-faced seals, and internal flush plans, and it is the condition of finished water, seal water, and most process transfer. Light silt, which raw water from a river or a reservoir carries and washwater carries in its return, embeds in a carbon seal face and lodges in a wear ring, so it moves the seal faces to hard-on-hard and the flush to a cleaned source without changing the hydraulics. Abrasive sand or grit, which raw water from a well field or an unsettled intake carries, wears the wear rings and the impeller eye on every pass and is the condition under which hardened rings, an external flush, and a wider ring clearance are specified. (5.1.5)
5.1.6 Where the pumped liquid is a chemical solution, the Engineer of Record shall state the chemical, its concentration range, and its temperature range on the pump schedule, and the pump manufacturer shall certify in writing the compatibility of every wetted material with that solution.

5.2 Outdoor and Unheated Installations

5.2.1 Pumps installed outdoors or in a space that is not heated shall be furnished with casing and seal chamber drains, and shall be protected against freezing by heat tracing and insulation, by an enclosure heater, or by a drain-down procedure in the operation and maintenance manual, where Site Ambient Temperature MinimumSite Ambient Temperature MinimumParameterEach project supplies its own value.site-ambient-temperature-minimum is below 32°F.
NOTE A self-priming pump installed outdoors retains liquid in its priming chamber whenever it is stopped, so it freezes where a drained end-suction pump does not; the priming chamber drain and the heat tracing of the chamber are what keep a washwater pump at a remote basin alive through a cold snap. (5.2.2)

6 Hydraulic Selection

6.1 Rated Duty

6.1.1 Each pump shall be selected and certified to deliver the rated flow at the rated total dynamic head indicated in the datasheet, at the rated speed and with the impeller diameter stated in the selection report.
Rated Flowrange
gpm
10255010015020030050075010001500200030005000750010000150002000030000
Per drawings — the pump schedule (deferred by default)
Rated Total Dynamic Headrange
ft
10203040506075100125150200250300400500600800
Per drawings — the pump schedule (deferred by default)
6.1.2 The rated speed of each pump shall be as indicated in the datasheet.
Rated Speedrange
rpm
585705885118017803560
Per drawings — the pump schedule (deferred by default)
6.1.3 The number of pump units in each service, including the standby unit where one is scheduled, shall be as indicated in the datasheet.
Pump Units per Servicerange
units
1234568
Per drawings — the pump schedule and the process and instrumentation diagrams (deferred by default)
6.1.4 No margin shall be added to the scheduled flow or head by the Contractor or the pump manufacturer; where the selection requires margin, the Engineer of Record establishes it and the scheduled duty carries it.
NOTE The flow, the head, the speed, and the count of units are the Engineer of Record's hydraulic design, settled on the pump schedule before the standard is read, and the standard takes them as given. Stacked margins are the common cause of an oversized plant pump: the Engineer adds to the calculated head, the manufacturer selects the next impeller up, and the pump then runs for thirty years to the left of its best efficiency point, where it wears fastest. (6.1.5)
NOTE Where a standard speed of 1780 rpm and of 3560 rpm can each produce the duty, the two selections differ in almost everything but the duty point: the faster pump is smaller, cheaper, and reaches high head in one stage, and it needs materially more suction head, wears its seal faces and bearings in proportion to its speed, and radiates more noise into the pump room. Water plants with continuous service and plentiful suction head on the one hand, and high-head, low-flow washwater or transfer duty on the other, usually land on opposite speeds for those reasons. (6.1.6)

6.2 Operating Region

6.2.1 The rated point of each pump shall fall within the operating region indicated in the datasheet, determined under ANSI/HI 9.6.3 for the specific speed of the pump furnished.
Operating Region at the Rated Pointradio
● Preferred operating region per ANSI/HI 9.6.3
○ Allowable operating region per ANSI/HI 9.6.3
6.2.2 No pump shall operate outside its allowable operating region at any condition the system and the control sequence can produce, including single-pump runout with the system fully open and the parallel operation of every duty unit.
6.2.3 Where a pump will operate across a range of system head curves, as with a clearwell whose level varies or a distribution system whose pressure varies, the selection report shall show the operating point on the highest and the lowest system curve and shall confirm both within the allowable operating region.
NOTE The preferred region is not a fixed band: ANSI/HI 9.6.3 puts it as wide as 70 to 120 percent of BEP flow for a low specific speed pump and narrows it as specific speed rises, so the acceptable window has to be read for the pump actually selected rather than assumed from the hydronic rule of thumb. (6.2.4)
NOTE The two ways out of the region fail differently. To the left of BEP, suction and discharge recirculation inside the impeller drive radial load, noise, and seal chamber turbulence at flows that look harmless on the curve; to the right, radial load rises again and NPSHr climbs steeply, so a pump that runs out when a second unit drops offline can cavitate at a condition nobody tested. (6.2.5)

6.3 Impeller Trim and Curve Shape

6.3.1 The furnished impeller diameter shall not exceed the percentage of the maximum catalog diameter indicated in the datasheet, and shall not be below the smallest trim the manufacturer publishes for the casing.
Impeller Diameter, Percent of Maximum Catalog Diameterrange
%
707580859095100
6.3.2 The head-capacity curve of each pump shall rise continuously from the rated point to shutoff, with no dip, flat, or reversal, and the shutoff head shall be not less than the percentage of the rated head indicated in the datasheet.
Shutoff Head, Percent of Rated Headrange
%
105110115120125130140
NOTE Headroom below the maximum catalog diameter is insurance against a system that turns out stiffer than calculated, because a larger impeller can be fitted in the same casing while a pump already at maximum diameter has to be replaced; the water and wastewater specifications that cap the trim put it between 85 and 95 percent for that reason, and a cap near 100 percent is the position where the duty sits at the top of the casing's range and the next casing size would run far to the left of BEP. Trimming far below the maximum costs efficiency, because the trimmed vane no longer matches the volute. (6.3.3)
NOTE A continuously rising curve is what lets parallel units share the load: a curve with a flat or a dip near shutoff lets two pumps find two different flows at the same head, so one pump backs the other down below its minimum flow while the control system reports both running. The shutoff rise is also what gives a variable-speed pump a controllable range, because a flat curve changes flow only a little for a large change in speed near the top of the system curve. A rise of 110 to 125 percent is the range most selections fall in; a steeper rise is bought where the system is a long force main whose friction dominates, and it costs efficiency at the rated point. (6.3.4)

6.4 Net Positive Suction Head

6.4.1 The NPSH available at the pump suction at the rated flow, calculated by the Engineer of Record for the atmospheric pressure at AltitudeAltitudeParameterEach project supplies its own value.altitude, the lowest suction level, the suction piping losses, and the vapor pressure of the liquid at its highest temperature, shall be as indicated in the datasheet.
NPSH Available at Rated Flowrange
ft
510152025303540506080100
Per drawings — the pump schedule (deferred by default)
6.4.2 The NPSH available shall exceed the NPSH3 of the pump furnished by not less than the margin ratio indicated in the datasheet, at the rated flow and at runout.
NPSH Margin Ratio, NPSHa Divided by NPSH3range
11.11.21.31.51.7522.5
6.4.3 The NPSH available shall exceed the NPSH3 of the pump furnished by not less than the margin in feet indicated in the datasheet, applied in addition to the margin ratio.
NPSH Margin in Feetrange
ft
2357101520
6.4.4 Where the datasheet indicates neither a margin ratio nor a margin in feet, the margin shall be established under ANSI/HI 9.6.1 for the suction energy of the pump furnished and the service, and the value used shall be stated in the selection report.
6.4.5 Where the required NPSH margin is not met at any condition the system can produce, the Contractor shall report the shortfall to the Engineer of Record in writing before the pump is released for fabrication.
NOTE ANSI/HI 9.6.1 publishes a band of margin ratios rather than one number, selected by suction energy and by service, so a low suction energy end-suction pump on a flooded clearwell and a very high suction energy split-case pump on a long intake line land at opposite ends of it. A ratio alone behaves badly at small numbers, which is why a margin in feet is specified beside it: 1.2 times an NPSH3 of 5 ft leaves 1 ft of real margin, and NPSH3 is by definition the point at which the pump has already lost 3 percent of its head to cavitation. (6.4.6)
NOTE Cavitation from a thin margin is quiet at first. It removes metal from the vane just behind the leading edge, where nothing is visible until the impeller comes out, and the first symptom an operator notices is usually a seal that will not stay in service. (6.4.7)

6.5 Efficiency and Energy Index

6.5.1 The hydraulic efficiency of each pump at the rated point shall be not less than the value indicated in the datasheet.
Pump Hydraulic Efficiency at the Rated Pointrange
%
4050556065707578808285889092
6.5.2 Where the datasheet indicates no efficiency, the certified efficiency at the rated point shall be reported for each pump and compared in the selection report against the manufacturer's published BEP efficiency for that pump.
6.5.3 Where the pump falls within an equipment class regulated under 10 CFR Part 431 Subpart Y, its pump energy index, determined under ANSI/HI 40.6, shall not exceed the value indicated in the datasheet, and the submittal shall state whether the constant-load or the variable-load index is reported.
Pump Energy Indexrange
0.50.60.70.80.90.951
Default: Not more than 1
6.5.4 Where the pump falls outside the regulated equipment classes, the submittal shall state which scope limit places it outside rather than omitting the index.
NOTE Achievable efficiency is a function of size, specific speed, and configuration, so no single number spans this standard: a 100 gpm seal water pump and a 20,000 gpm double-suction raw water pump differ by more than twenty points at their respective best points, and a minimum written for one is either trivial or unbuildable for the other. The regulated classes are end-suction close-coupled, end-suction frame-mounted, and the in-line and vertical turbine classes, bounded by 25 gpm and more at BEP, 459 ft and less of head, 1 to 200 hp, and two-pole or four-pole speeds, so a large split-case pump and a slow-speed raw water pump both fall outside them. (6.5.5)

6.6 Speed Control and Low-Flow Protection

6.6.1 Each pump shall be driven under the speed control indicated in the datasheet.
Speed Controlradio
○ Constant speed
○ Variable speed, variable frequency drive
○ Two-speed motor
6.6.2 Where variable speed is selected, the drive shall conform to Low Voltage Variable Frequency DrivesLow-Voltage Variable Frequency DrivesResolves to the current adopted revision.sync/low-voltage-variable-frequency-drives, and the pump shall operate continuously at any speed between the lowest continuous operating speed indicated in the datasheet and the rated speed without leaving its allowable operating region on any system curve the selection report shows.
Lowest Continuous Operating Speed, Percent of Rated Speedrange
%
2530405060708090
Derived — the lowest system head curve on the pump schedule and the allowable operating region of the pump furnished (by default)
6.6.3 The minimum continuous stable flow published by the pump manufacturer shall be stated on the certified curve, and where the system or the control sequence can hold the pump below it, low-flow protection shall be provided as indicated in the datasheet.
Low-Flow Protectionradio
○ Continuous minimum-flow bypass to the suction source
○ Automatic recirculation valve on the discharge
○ Control sequence limits that hold flow above the minimum
○ None, the system holds flow above the minimum continuous stable flow
NOTE Constant speed is the arrangement of a pump that fills a tank or feeds a filter at a fixed rate and of a duty-standby pair that runs one unit at a time, and it costs the least to buy and to maintain. A variable frequency drive follows a varying demand without throttling and is what a distribution high-service pump or a transfer pump into a system whose pressure moves is driven by, at the price of the drive, its harmonics, and a minimum speed below which the pump leaves its region. A two-speed motor gives two fixed duties without a drive and is the position of a washwater or raw water pump with two scheduled rates and no demand in between. (6.6.4)
NOTE The lowest usable speed is set by the system, not by the drive: on a system whose head is mostly static, a pump slowed below the speed at which its shutoff head equals the static head delivers nothing, and well above that speed it is already outside its allowable region; on a system whose head is mostly friction the pump can be slowed far further. The value follows from the lowest system curve and the region limits, which is why it is derived here from the selection rather than chosen. (6.6.5)
NOTE A pump held below its minimum continuous stable flow converts most of its shaft power into heat and recirculation. A bypass to the suction source wastes the bypassed energy continuously and never fails; an automatic recirculation valve opens the bypass only when flow falls and is a mechanical device in the discharge that is serviced; control limits cost nothing and protect the pump only as long as the control system is in automatic; and no protection is the position of a pump whose system cannot throttle it, such as a constant-speed pump into an open channel. (6.6.6)

7 Pump Configuration

7.1 Configuration Selection

7.1.1 The configuration of each pump shall be as indicated in the datasheet.
Pump Configurationselect
End suction, frame mounted, back pull-out
End suction, frame mounted, ASME B73.1 chemical process pump
End suction, close coupled
Axially split case, double suction
Self-priming centrifugal
7.1.2 The discharge nozzle orientation, the direction of rotation viewed from the driver, and the suction and discharge nozzle sizes of each pump shall be as indicated on the process mechanical plans and the pump schedule.
NOTE Configuration is a consequence of the flow, the suction arrangement, and the maintenance the Owner intends to do, which is why the field carries no default. A frame-mounted end-suction pump covers the middle of plant water duty, up to a few thousand gallons per minute, and its back pull-out construction lets the rotating element come out through the back of the casing with the suction and discharge piping undisturbed. The ASME B73.1 pump is the same arrangement built to a dimensional standard, so that any B73.1 pump of the same size from any manufacturer bolts to the same baseplate and the same piping, with a seal chamber sized for a cartridge seal and the alloys a chemical solution needs. (7.1.3)
NOTE A close-coupled pump mounts the impeller on an extended motor shaft and removes the coupling, the baseplate, and the alignment, and the motor comes out to reach the seal; it is the arrangement of seal water, sample, and small transfer duty where the motor is light enough to lift by hand. An axially split-case double-suction pump balances its axial thrust hydraulically, carries its rotor on bearings at both ends, and opens by lifting the upper half of the casing with the piping and the motor in place; it is the arrangement of raw water, high-service, and washwater duty at the flows where a single end-suction impeller would be too large for its own shaft. (7.1.4)
NOTE A self-priming pump evacuates the air from its own suction line and reprimes after every stop, so it can sit above the liquid it pumps; it is the arrangement of a washwater return, a basin drain, or a tank transfer where a flooded suction would require a pit, and it pays for that with a lower efficiency, a priming time that lengthens with the lift and with AltitudeAltitudeParameterEach project supplies its own value.altitude, and a casing that must retain liquid between runs. (7.1.5)

7.2 Impeller Type

7.2.1 The impeller of each pump shall be of the type indicated in the datasheet, keyed to the shaft and secured against loosening in the direction of rotation.
Impeller Typeradio
● Enclosed
○ Semi-open
○ Open
7.2.2 The impeller shall be dynamically balanced under ISO 21940-11 to the grade selected under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, and the balance record shall be furnished on request.
NOTE An enclosed impeller carries a shroud on both sides of the vanes, so its running clearance is set by renewable wear rings rather than by the casing wall, and that is what makes the clearance restorable at overhaul and why enclosed construction is the norm in clean water. A semi-open impeller has one shroud and runs against the casing wall or a wear plate with a clearance that is adjusted axially rather than renewed, which suits a liquid with light solids or a chemical service where a ring would corrode; an open impeller has no shroud and passes stringy material at the lowest efficiency of the three, and it is the construction of the self-priming pump and of the few clean-liquid duties where a solid can arrive. (7.2.3)

7.3 End-Suction Frame-Mounted Construction

7.3.1 Requirements in this article apply where an end-suction frame-mounted configuration is selected in the datasheet.
7.3.2 The pump shall be of back pull-out construction, so that the bearing frame, shaft, seal, and impeller can be withdrawn from the casing as an assembly without disconnecting the suction or discharge piping or moving the motor.
7.3.3 The bearing frame shall carry the rotor on an antifriction thrust bearing and an antifriction radial bearing, with the thrust bearing sized for the axial load at the ends of the allowable operating region.
7.3.4 Where the ASME B73.1 configuration is selected, the pump shall conform to ASME B73.1 in its dimensions, its seal chamber, its baseplate interface, and its pressure and temperature ratings, and the shaft deflection at the seal faces shall not exceed the limit that standard sets.
NOTE A pump that is not back pull-out can be a few percent cheaper and costs that back on the first seal change, when the piping has to come apart to reach the impeller. The B73.1 dimensional standard is what makes a chemical process pump replaceable from a second source without a new baseplate, and its seal chamber dimensions are what make a cartridge seal from any seal manufacturer fit it. (7.3.5)

7.4 Close-Coupled Construction

7.4.1 Requirements in this article apply where the close-coupled configuration is selected in the datasheet.
7.4.2 The motor shall be a NEMA C-face or JM or JP frame motor with the impeller mounted on the motor shaft extension, and the motor bearings shall be selected by the pump manufacturer for the radial and axial loads the impeller imposes.
7.4.3 The motor shaft through the seal chamber shall be protected by a renewable stainless steel sleeve or shall be of stainless steel, so that a seal change does not require a new motor.
7.4.4 A slinger or deflector shall be fitted on the motor shaft between the seal chamber and the motor bearing, so that a seal leak drains away from the motor rather than into it.
NOTE The close-coupled pump trades the alignment problem for a dependence on the motor: the motor bearings are the pump bearings, a seal that leaks past the slinger ends in the motor, and a motor replacement is a special-shaft motor rather than a stock one. Those are workable on the small pump the arrangement suits and are the reason the arrangement is not carried to large duty. (7.4.5)

7.5 Axially Split-Case Construction

7.5.1 Requirements in this article apply where the axially split-case double-suction configuration is selected in the datasheet.
7.5.2 The casing shall be split on the horizontal centerline, with the suction and discharge nozzles cast in the lower half, so that the upper half and the complete rotating element can be removed without disconnecting the piping or moving the motor.
7.5.3 The casing halves shall be doweled for alignment and bolted with a confined gasket, and the rotor shall be carried on antifriction bearings in housings at both ends of the shaft, each removable without disturbing the other.
7.5.4 The impeller shall be of the double-suction type, with wear rings at both eyes, and the rotor shall be balanced as an assembly with the shaft and sleeves.
7.5.5 Lifting lugs or eyes shall be cast or fitted on the upper half of the casing, rated for the weight of the upper half with the rotor.
NOTE The split-case pump exists so that a 10,000 gpm rotor can be inspected in an afternoon: lift the upper half, lift the rotor, and the piping and the motor stay where they are. A pump whose nozzles are in the upper half, or whose bearing housings have to come apart together, gives that up and should not be confused with the real thing. (7.5.6)

7.6 Self-Priming Construction

7.6.1 Requirements in this article apply where the self-priming centrifugal configuration is selected in the datasheet.
7.6.2 The pump shall prime and reprime from the static suction lift indicated in the datasheet, corrected for AltitudeAltitudeParameterEach project supplies its own value.altitude and for the liquid temperature indicated in this standard, without a foot valve, a vacuum pump, or external priming.
Static Suction Liftrange
ft
5810121518202225
Per drawings — the pump schedule (deferred by default)
7.6.3 The pump shall reach full flow from a dry suction line at the rated static lift within the priming time indicated in the datasheet, with the suction line length and diameter the drawings show.
Priming Time at the Rated Static Liftrange
minutes
12345710
7.6.4 The casing shall retain enough liquid after a stop to reprime without refilling, and shall be furnished with a fill port, a drain, and a suction check or flap valve that holds the retained liquid without preventing repriming when the suction line has drained.
NOTE The published repriming lift of a self-priming pump falls by roughly 1 ft for every 1,000 ft of altitude and by several feet as the liquid approaches 100°F, and the priming time grows with the air volume in the suction line, so a pump that primes in a minute on the test stand at sea level with 10 ft of suction pipe can take several minutes at a mountain site on a long line. The lift on the schedule is the one the Engineer of Record measured from the lowest liquid level to the impeller centerline, and the pump manufacturer corrects it. (7.6.5)

8 Casing and Pressure Boundary

8.1 Connections and Taps

8.1.1 The suction and discharge connections of each pump shall be of the type indicated in the datasheet.
Pump Connection Typeselect
Flanged, ASME B16.1 Class 125
Flanged, ASME B16.1 Class 250
Flanged, ASME B16.42 Class 150
Flanged, ASME B16.5 Class 150
Flanged, ASME B16.5 Class 300
Grooved end
Threaded, NPT
8.1.2 Cast iron flanges shall conform to ASME B16.1, ductile iron flanges to ASME B16.42, and steel and stainless steel flanges to ASME B16.5, for the class furnished, and the mating flange, gasket, and bolting on the piping side shall conform to the process piping standard governing that piping.
8.1.3 The casing shall be furnished with the tapped connections indicated in the datasheet, each plugged or fitted with a valve before shipment.
Casing Tapped Connectionscheckbox
☑ Casing drain at the low point
☑ Casing vent at the high point
☑ Suction gauge tap
☑ Discharge gauge tap
☐ Seal chamber flush connection
☐ Seal chamber drain
8.1.4 The pressure gauges, transmitters, and switches connected to the gauge taps shall be furnished under Pressure InstrumentationPressure InstrumentationResolves to the current adopted revision.sync/pressure-instrumentation, and the flow meter on the pump discharge, where one is scheduled, under Flow MeasurementFlow MeasurementResolves to the current adopted revision.sync/flow-measurement.
NOTE A Class 125 cast iron flange mates with the flat-faced Class 125 and AWWA C115 flanges of ductile iron plant piping and carries the 175 psig that nearly every plant water service stays under, which is why it is the connection most horizontal process pumps ship with. Class 250 and Class 300 flanges are bought for a high-service pump whose discharge pressure or whose surge analysis exceeds that rating, and a steel flange is bought where the casing is steel or stainless and a raised face is wanted. Grooved and threaded connections serve the small seal water and transfer pumps installed in steel or plastic piping, where a flange is larger than the pump. (8.1.5)

8.2 Casing Pressure Rating

8.2.1 The casing and its connections shall be rated for a working pressure not less than the value indicated in the datasheet at the liquid temperature indicated in this standard.
Casing Working Pressure Ratingrange
psig
125150175200250300400600
Derived — the shutoff head of the pump furnished at the rated speed added to the highest suction pressure the pump can see while shut down, both stated on the pump schedule (by default)
8.2.2 Where the pump can see the static pressure of the system it discharges to while shut down, that pressure shall be included in the suction pressure used to establish the casing rating.
8.2.3 The casing shall be hydrostatically tested at the factory at not less than 1.5 times its rated working pressure, held for not less than 10 minutes with no leakage through the casting, the joints, or the seal chamber.
NOTE A casing sees its highest pressure not at the rated point but at shutoff on the highest suction pressure, which on a pump drawing from a pressurized main or a tall clearwell is the suction pressure plus the full shutoff head, and a casing rated for the rated discharge pressure can be below that number. The rating follows from the selection and the schedule, which is why it is derived here rather than chosen. (8.2.4)

8.3 Casing Material

8.3.1 The casing of each pump shall be of the material indicated in the datasheet.
Casing Materialselect
Cast iron
Ductile iron
Bronze
Stainless steel, Type 316
Stainless steel, duplex
Alloy 20
8.3.2 Cast iron casings shall conform to ASTM A48/A48M Class 30 or higher, ductile iron casings to ASTM A536, bronze casings to ASTM B584, Type 316 casings to ASTM A743/A743M grade CF8M, and duplex casings to ASTM A890/A890M.
NOTE Cast iron holds its dimensions, pours cleanly in the complex volute shape, and corrodes slowly enough in raw, finished, and service water to last the life of the pump, which is why it is the casing of nearly every plant water pump. Ductile iron is bought where the casing rating or the piping loads exceed what a gray iron casting carries, and it is the casing of the ASME B73.1 pump in all but the alloy services. Bronze resists the aerated, chloride-bearing, or soft water that pits iron and is the casing of a seal water or sample pump that is drained and refilled. Type 316 is the casing of a chemical solution the iron would not survive, duplex of a chloride-bearing solution that would pit Type 316, and Alloy 20 of sulfuric acid and the other services the B73.1 alloy tables name it for. (8.3.3)

8.4 Casing Interior Lining

8.4.1 The interior of the casing shall be finished as indicated in the datasheet.
Casing Interior Finishradio
○ Uncoated casting
○ Epoxy lining certified under NSF/ANSI/CAN 61
○ Fusion-bonded epoxy lining
8.4.2 Where a lining is furnished, it shall be applied over a surface prepared under SSPC-SP 10/NACE No. 2, to the dry film thickness the lining manufacturer publishes for immersion service, measured under SSPC-PA 2, and shall not reduce any running clearance or cover any machined face.
NOTE An uncoated iron casing is the pump as sold and is what most raw, service, and washwater pumps run with; the surface rusts to a stable film in the first weeks and the casing loses nothing to it in decades. A liquid epoxy lining is bought in finished water, where the NSF/ANSI/CAN 61 certification of the lining is what the regulator looks for and the lining keeps iron out of the water, and in soft or aggressive raw water. A fusion-bonded epoxy lining is harder and thinner than a liquid epoxy, is applied by the foundry rather than the pump shop, and is bought where abrasive solids would cut a liquid-applied film. A bronze or stainless casing is left uncoated in every service. (8.4.3)

9 Rotating Element

9.1 Impeller Material

9.1.1 The impeller of each pump shall be of the material indicated in the datasheet.
Impeller Materialselect
Bronze
Cast iron
Ductile iron
Stainless steel, Type 316
Stainless steel, duplex
Alloy 20
9.1.2 Bronze impellers shall conform to ASTM B584, cast iron impellers to ASTM A48/A48M, ductile iron impellers to ASTM A536, Type 316 impellers to ASTM A743/A743M grade CF8M, and duplex impellers to ASTM A890/A890M.
NOTE A bronze impeller in an iron casing is the bronze-fitted pump the water industry has bought for a century: the bronze takes a fine finish that holds efficiency, resists the erosion at the vane tips that iron does not, and sits in a galvanic pair in which the much larger iron casing is the anode, so the current density on the casing stays low. An iron impeller is the lowest cost and is bought in service water where nobody will ever open the pump; ductile iron is bought for a larger impeller whose tip speed would overstress gray iron. Type 316 replaces bronze in finished water where the lead content rule is answered by eliminating copper alloy rather than by a lead-free bronze, and in the chemical solutions that attack bronze; duplex and Alloy 20 follow the casing into the services that need them. (9.1.3)

9.2 Wear Rings

9.2.1 Pumps with enclosed impellers shall be furnished with renewable wear rings in the arrangement indicated in the datasheet, secured against rotation and renewable without machining the casing or the impeller.
Wear Ring Arrangementradio
○ Renewable rings on both the casing and the impeller
○ Renewable casing ring only
○ No renewable rings, clearance formed by the casing and impeller
9.2.2 Wear rings shall be of the material indicated in the datasheet, selected so that the ring pair does not gall on contact, which for a metallic pair means a Brinell hardness difference of not less than 50 between the two rings.
Wear Ring Materialselect
Bronze
Stainless steel, Type 316
Hardened stainless steel
Filled fluoropolymer or engineered polymer
Not applicable, no renewable rings
9.2.3 The manufacturer shall state in the submittal the design diametral clearance of the wear rings and the clearance at which the manufacturer recommends renewal.
NOTE The wear ring clearance is the only path from the discharge side of the impeller back to the suction eye, and as it opens the pump recirculates an increasing share of its own flow: the head-capacity curve barely moves while efficiency falls steadily, which is why the loss goes unnoticed until someone measures brake horsepower against flow. Rings on both the casing and the impeller restore the original clearance at overhaul for the price of two rings; a casing ring alone restores it only until the impeller hub has worn; and no rings is the construction of a small close-coupled pump whose casing and impeller cost less than the rings would. (9.2.4)
NOTE Bronze rings in an iron casing with a bronze impeller are the bronze-fitted pump's rings and serve clean and silty water; a bronze ring is not run against a bronze impeller hub without a hardness difference, which is why the impeller ring is often a harder alloy. Type 316 rings follow a stainless impeller, and hardened stainless rings, with a hardness difference of 50 Brinell or more against the mating ring, are the rings of abrasive raw water. A filled fluoropolymer or engineered polymer ring runs at a tighter clearance than a metal ring, because it does not gall on a momentary rub, and it recovers a point or two of efficiency on a large pump at the price of a temperature limit and a ring that cannot be reused. (9.2.5)

9.3 Shaft and Shaft Sleeve

9.3.1 The shaft of each pump shall be of the material indicated in the datasheet, sized so that the deflection at the seal faces stays within the seal manufacturer's limit across the allowable operating region and the first lateral critical speed is above the rated speed by the margin ANSI/HI 1.3 describes.
Shaft Materialselect
Carbon steel
Alloy steel
Stainless steel, Type 416
Stainless steel, Type 316
Stainless steel, 17-4 PH
Stainless steel, duplex
9.3.2 Stainless steel shafts shall conform to ASTM A276/A276M for the grade furnished, and precipitation-hardening stainless shafts to ASTM A564/A564M.
9.3.3 A renewable shaft sleeve shall be provided as indicated in the datasheet, extending through the seal chamber or stuffing box and sealed against leakage between the sleeve and the shaft.
Shaft Sleeveradio
● Renewable sleeve through the seal chamber
○ No sleeve, seal runs directly on the shaft
9.3.4 Shaft sleeves shall be of bronze conforming to ASTM B505/B505M or of Type 316 or a harder stainless steel, and shall be keyed or pinned against rotation.
NOTE A carbon or alloy steel shaft is the shaft of a sleeved pump in water, where the sleeve is the wetted part and the shaft is dry; Type 416 adds corrosion resistance under the sleeve at little cost and is the shaft many water pump manufacturers fit as standard; Type 316 is the shaft of a pump without a sleeve or in a chemical solution, and it is the weakest of the stainless choices, which limits it on a long split-case rotor; 17-4 PH carries the strength of alloy steel with the corrosion resistance of a stainless and is the shaft of the high-speed, high-head pump; duplex follows a duplex casing. (9.3.5)
NOTE A sleeve moves the wear surface off the shaft onto a part that costs a fraction as much to replace, at the price of a slightly larger shaft through the seal chamber and a second leak path at the sleeve joint; it is the construction of nearly every packed pump and of most mechanically sealed water pumps. Running the seal directly on a corrosion-resistant shaft removes the joint and is the arrangement of the B73.1 pump with a cartridge seal and of the close-coupled pump with a stainless motor shaft. (9.3.6)

9.4 Bearings and Lubrication

9.4.1 Bearings shall be of the lubrication type indicated in the datasheet, arranged to carry the radial and axial loads the pump develops across its allowable operating region.
Bearing Lubricationradio
○ Grease-lubricated antifriction bearings, regreasable
○ Oil bath antifriction bearings with constant-level oiler
○ Oil mist lubrication
○ Sealed-for-life antifriction bearings
9.4.2 Bearings shall be selected for an L10 rating life not less than the value indicated in the datasheet, calculated at the rated point, and the calculated life at the limits of the allowable operating region shall be stated in the bearing data submittal.
Bearing L10 Rating Life at the Rated Pointrange
hours
1750025000400005000075000100000
9.4.3 Bearing housings shall be sealed against the entry of water and dust by labyrinth or lip seals, and grease fittings, relief fittings, oil fill, and sight glass shall be reachable without removing the coupling guard.
9.4.4 Where oil lubrication is furnished, the bearing housing shall carry a constant-level oiler, a sight glass, a drain, and a vent, and the oil grade and change interval shall be stated in the operation and maintenance manual.
NOTE Grease lubrication is the lubrication of most water pumps below a few hundred horsepower: it is maintained with a grease gun on an interval, it tolerates a housing that is not level, and it is destroyed by over-greasing more often than by neglect, which is why the interval and quantity in the manual matter. An oil bath carries heat away from a large or fast bearing better than grease and is the lubrication of the split-case pump and the B73.1 frame, at the price of a housing that must be level, an oiler that must be kept full, and an oil change on a schedule. Oil mist feeds a measured mist from a central console to every bearing on the plant floor and is bought where a plant already runs one, and sealed bearings are the bearings of the small close-coupled motor that will be replaced before its bearings are. (9.4.5)
NOTE The 17,500 hour L10 life at maximum load is the floor ASME B73.1 sets, and the 50,000 hour life at the rated point is the one most water and wastewater pump specifications carry; the two are not comparable, because the load at the end of the allowable region can be several times the load at the rated point, which is why the submittal states both. A life of 100,000 hours is bought on a continuously running raw water or high-service pump that the plant intends to run for two decades between overhauls. (9.4.6)

10 Shaft Sealing

10.1 Seal Type

10.1.1 The shaft seal of each pump shall be of the type indicated in the datasheet, rated for the seal chamber pressure and the liquid temperature at every condition the system can produce, including the suction pressure the pump sees while shut down.
Shaft Seal Typeselect
Packed stuffing box with lantern ring
Single mechanical seal, component type
Single mechanical seal, cartridge type
Dual mechanical seal, unpressurized buffer fluid
Dual mechanical seal, pressurized barrier fluid
10.1.2 The seal chamber or stuffing box shall be cast integrally with the casing or the frame adapter, and a mechanical seal shall be installable and removable without removing the impeller.
10.1.3 Where a mechanical seal is furnished, the seal chamber shall be the enlarged bore or tapered bore the seal manufacturer specifies for the seal furnished, and the shaft or sleeve runout at the seal faces shall be stated in the submittal.
NOTE Packing is the oldest seal and the one the water industry still runs on large split-case pumps: it is adjusted with a wrench, it fails slowly and visibly, it is repacked in place without lifting the casing, and it must leak to live, so it costs a continuous drip to a drain and a sleeve that scores when an operator tightens it to stop the drip. A component mechanical seal leaks nothing in service, is the lowest cost mechanical seal, and is set in the field by measurement, where a sixteenth of an inch of error either leaks at once or runs the faces hot. A cartridge seal arrives preset on its own sleeve and gland, slides on, and releases its setting clips, so a plant maintenance crew installs it as reliably as a pump shop does, at a higher price and a seal chamber that must accept it. (10.1.4)
NOTE A dual seal puts a second seal between the pumped liquid and the atmosphere with a buffer or barrier fluid between the two. The unpressurized arrangement contains the leakage of the inner seal in the buffer fluid and alarms on it; the pressurized arrangement holds the barrier fluid above seal chamber pressure, so that the faces run on the barrier fluid and nothing pumped ever reaches the atmosphere, which is the arrangement of a chemical solution that cannot be allowed to leak or an abrasive liquid that would destroy a single seal. Both cost a reservoir or a supply system that becomes part of the pump. (10.1.5)

10.2 Seal Flush Plan

10.2.1 The seal flush arrangement shall be the API 682 plan indicated in the datasheet, and the flush piping, orifices, and fittings from the casing to the seal chamber shall be furnished and mounted by the pump manufacturer.
Seal Flush Planselect
Plan 02, dead-ended seal chamber without flush
Plan 11, recirculation from the pump discharge through an orifice to the seal chamber
Plan 13, recirculation from the seal chamber back to the pump suction
Plan 21, recirculation from the discharge through a cooler to the seal chamber
Plan 31, recirculation from the discharge through a cyclone separator to the seal chamber
Plan 32, external flush from a clean source to the seal chamber
Plan 52, unpressurized buffer fluid reservoir serving a dual seal
Plan 53A, pressurized barrier fluid reservoir serving a dual seal
Plan 62, external quench to the atmospheric side of the seal
10.2.2 Where a Plan 31 cyclone separator is furnished, its reject line shall be piped to the pump suction and shall not be valved closed.
10.2.3 Where a Plan 32 external flush, a Plan 62 quench, or a packed stuffing box flush is furnished, the pump manufacturer shall state the pressure and flow required at the connection in the shaft seal data, and the seal water or flush supply piping to that connection shall be as indicated on the process mechanical plans.
NOTE The flush plans are API 682 numbers used as a vocabulary, and the ones this standard lists are the plans a water or chemical transfer pump actually uses; the pump is not an API pump and does not become one by carrying a plan number. Plan 11 is the plan of nearly every mechanically sealed clean water pump: discharge liquid cools and sweeps the faces and carries whatever the pump carries. Plan 13 reverses the flow and is the plan of a vertical or a pump whose seal chamber pressure is near discharge pressure. Plan 21 adds a cooler for a hot liquid, and Plan 31 adds a cyclone that returns the solids-laden fraction to the suction and sends cleaned liquid to the faces, which is the plan of a silty raw water pump. Plan 32 brings clean water from outside the pump and is the plan of an abrasive or a chemical service and of every packed box with a lantern ring, at the price of a supply that must be there whenever the pump runs. Plan 52 and 53A are the dual-seal plans, and Plan 62 washes the atmospheric side of a seal in a crystallizing solution. Plan 02 is the plan of a small, cool, low-pressure pump whose seal needs nothing. (10.2.4)

10.3 Mechanical Seal Faces and Elastomers

10.3.1 Requirements in this article apply where a mechanical seal is selected in the datasheet.
10.3.2 The seal face combination shall be as indicated in the datasheet.
Mechanical Seal Face Combinationselect
Carbon against alumina ceramic
Carbon against silicon carbide
Carbon against tungsten carbide
Silicon carbide against silicon carbide
Tungsten carbide against silicon carbide
10.3.3 The seal elastomers shall be as indicated in the datasheet and shall be compatible with the pumped liquid, its disinfectant or treatment chemistry, and the liquid temperature indicated in this standard.
Seal Elastomerselect
EPDM
Fluoroelastomer, FKM
Perfluoroelastomer, FFKM
Nitrile, NBR
Tetrafluoroethylene propylene, FEPM
10.3.4 Metal parts of the seal, including the springs, the gland, and the sleeve, shall be of Type 316 stainless steel or a more corrosion-resistant alloy.
NOTE Carbon running against a hard seat is the low-friction pairing and the one that forgives a dry start, because the carbon sacrifices itself rather than heat-checking the seat; it is the pairing of finished water, seal water, and clean transfer, and what it does not forgive is particulate, which embeds in the carbon and laps the seat. Silicon carbide and tungsten carbide seats differ in thermal conductivity, cost, and chemical resistance, with silicon carbide the better conductor and the one that resists most chemicals and tungsten carbide the tougher one against shock. Silicon carbide against silicon carbide, or tungsten carbide against silicon carbide, resist the embedding of silt and sand and are the pairings of raw water and washwater, and they run hotter and are far less forgiving of a dry start, so they trade one failure mode for another. (10.3.5)
NOTE EPDM is compatible with water, with chlorine and chloramine at the residuals a plant carries, and with the sodium hypochlorite, caustic, and lime that reach a water pump, which is why it is the elastomer of nearly every water pump seal; it is attacked by oils and hydrocarbons, so a pump that can see a lubricant or a fuel needs a different one. Fluoroelastomer resists oils, acids, and oxidizers and is the elastomer of a chemical transfer pump, and it is attacked by hot water, steam, and strong caustic, so the two are nearly complementary. Perfluoroelastomer resists almost everything at many times the price, FEPM covers the hot caustic and the amine services fluoroelastomer does not, and nitrile is the elastomer of an oil-contaminated service at the lowest price. (10.3.6)

10.4 Packed Stuffing Box

10.4.1 Requirements in this article apply where a packed stuffing box is selected in the datasheet.
10.4.2 The stuffing box shall be furnished with a lantern ring, a flush connection to the lantern ring, a drain connection, and a two-piece gland of bronze or Type 316 stainless steel with stainless steel gland bolts and nuts.
10.4.3 The packing shall be of the material indicated in the datasheet, in not fewer than five rings with the lantern ring positioned so that the flush reaches the shaft sleeve under the inboard rings.
Packing Materialselect
Braided PTFE-impregnated synthetic fiber
Braided flexible graphite
Braided aramid fiber
10.4.4 The operation and maintenance manual shall state the leakage rate the packing requires for cooling and the gland adjustment procedure, and the stuffing box drain shall be piped to a floor drain or a drain hub.
NOTE A PTFE-impregnated synthetic packing is the packing of most water pumps: it seals at a low gland load, runs cool, and takes a sleeve finish without scoring it, and it is limited to the temperatures and chemicals of water service. Flexible graphite carries heat away from the sleeve better than any other packing and runs at higher temperatures and pressures, at the price of a packing that is brittle to install and conducts galvanically against some sleeves. An aramid packing resists abrasion where the pumped liquid carries sand and is the hardest of the three on the sleeve, which is why it is run against a hardened sleeve or in alternating rings with a softer packing. (10.4.5)

11 Baseplate, Coupling, and Guard

11.1 Baseplate

11.1.1 Frame-mounted pumps and their motors shall be mounted on a common baseplate of the type indicated in the datasheet, stiff enough that the pump-to-motor alignment holds under the operating load, the piping loads the manufacturer publishes, and thermal growth.
Baseplate Typeselect
Fabricated steel baseplate
Cast iron baseplate
Polymer concrete baseplate
Stainless steel baseplate
Not applicable, close-coupled pump
11.1.2 The baseplate shall be furnished with the features indicated in the datasheet.
Baseplate Featurescheckbox
☑ Grout holes and vent holes in each compartment
☑ Drip rim with a tapped drain connection
☑ Leveling screws or jacking bolts at each anchor
☑ Machined mounting pads for the pump and the motor
☐ Lifting lugs rated for the assembled unit
☐ Motor alignment jacking screws
11.1.3 The baseplate shall be grouted with the grout indicated in the datasheet, placed under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process and Non Shrink GroutNon-Shrink GroutResolves to the current adopted revision.sync/non-shrink-grout so that the baseplate bears on the grout over its full area without voids.
Baseplate Groutradio
● Non-shrink cementitious grout
○ Epoxy grout
○ Not applicable, ungrouted mounting
11.1.4 The underside of a steel baseplate shall be blast-cleaned and primed with a primer the grout manufacturer accepts, and the baseplate shall be leveled on the leveling screws to the pump manufacturer's flatness tolerance, with the readings recorded, before grout is placed.
11.1.5 Where the Engineer of Record and the Contractor disagree whether a grouted baseplate contains voids, the Engineer of Record shall make the initial determination by sounding, and the cost of any resulting investigation shall be borne by the Contractor where voids are found and by the Owner where they are not.
NOTE A fabricated steel baseplate is the baseplate of nearly every frame-mounted process pump, built by the pump manufacturer to the frame and motor furnished, and it is a sheet metal pan until the grout under it turns it into a foundation. A cast iron baseplate is stiffer and damps vibration better, is heavier, and is offered in the sizes of the smaller pumps. A polymer concrete baseplate is cast as one stiff block with the mounting pads machined in, needs no grout and no drip rim, resists chemical spill, and is the baseplate the B73.1 pump is increasingly set on. A stainless steel baseplate is bought in a chemical room or a washdown area where a painted steel plate would corrode from the drip rim outward. (11.1.6)
NOTE A void under the baseplate turns it into a beam supported at its ends, and the flexure shows up as a vibration signature that reads exactly like a pump defect; more than one pump has been pulled and rebuilt to cure a hollow baseplate. Epoxy grout bonds to the steel, does not absorb the drip rim's oil and water, and tolerates vibration better than a cementitious grout, which is why it is bought under a large or fast pump; cementitious grout is the grout of the rest, placed and cured under its own standard. (11.1.7)

11.2 Drive Arrangement and Coupling

11.2.1 The pump shall be driven through the arrangement indicated in the datasheet.
Drive Arrangementradio
● Direct, through a flexible coupling
○ V-belt drive
○ Not applicable, close-coupled pump
11.2.2 Where a flexible coupling is furnished, it shall be of the type indicated in the datasheet, selected by the pump manufacturer for the motor torque, the starting method, and the misalignment the installation can produce, with a service factor not less than 1.5 on the motor nameplate horsepower.
Coupling Typeselect
Elastomeric jaw coupling
Elastomeric tire coupling
Metallic disc coupling
Metallic grid coupling
Gear coupling
11.2.3 On frame-mounted pumps the coupling shall include a spacer long enough to permit removal of the mechanical seal or the packing and the back pull-out assembly without moving the motor.
NOTE A direct coupled drive is the drive of nearly every process pump, because it transmits the motor's full efficiency at the motor's speed with one wear part in the coupling. A V-belt drive lets a pump run at a speed no standard motor offers, which is how a slow raw water pump or a pump whose duty was changed after the motor was bought is driven, at the price of belt losses, a belt tension that is checked, and a bearing load the pump's bearings must be sized for. (11.2.4)
NOTE An elastomeric element accommodates misalignment by deforming, so it also absorbs torque pulsation and electrically isolates the two shafts; it is a wear part whose condition is the thing a coupling guard is opened to inspect, and the jaw and tire forms differ in the misalignment they absorb and the element they wear. A metallic disc pack accommodates misalignment by flexing steel, with no wear part and no electrical isolation, and fails abruptly rather than gradually when its limit is exceeded, which is why it is bought on the large pump whose alignment is set by laser and recorded. A grid coupling carries high torque with a replaceable spring grid and a lubricated cover, and a gear coupling carries the highest torque of all and must be greased on a schedule, which is why the two are found on large, slow raw water pumps and rarely elsewhere. (11.2.5)

11.3 Belt Drive

11.3.1 Requirements in this article apply where a V-belt drive is selected in the datasheet.
11.3.2 The belt drive shall be furnished with matched belts, sheaves rated for the motor horsepower with a service factor not less than 1.5, a slide rail or adjustable motor base for belt tensioning, and the pump bearings shall be selected for the belt pull as well as the hydraulic loads.
11.3.3 The drive shall be guarded under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process with a guard that permits belt tension to be checked and the sheaves to be inspected without removing it.

11.4 Coupling and Shaft Guard

11.4.1 Every exposed coupling, shaft, and belt drive shall be guarded under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process and 29 CFR 1910.219, with a guard of the material indicated in the datasheet.
Coupling Guard Materialradio
○ Aluminum
○ Stainless steel, Type 316
○ Hot-dip galvanized steel
11.4.2 The guard shall be removable and replaceable without disturbing the pump or motor alignment, and shall expose the grease fittings, the oiler, and the seal gland for inspection where the manufacturer's arrangement permits.
NOTE An aluminum guard is light, non-sparking, and does not rust, and it is the guard most pump manufacturers ship; it corrodes where it is wetted by a chemical splash or sits on a wet steel baseplate without isolation. A stainless steel guard is the guard of a chemical room, a washdown area, and a plant that standardizes on stainless hardware, at several times the price. A galvanized steel guard is the lowest cost and the heaviest, and its coating is consumed by a corrosive atmosphere within a few years. (11.4.3)

12 Motor Interface

12.1 Motor Rating and Enclosure

12.1.1 The motor of each pump shall conform to Electric MotorsCommon Motor Requirements for Electrical EquipmentResolves to the current adopted revision.sync/electric-motors, shall be furnished and mounted by the pump manufacturer under the unit responsibility selected in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, and shall be rated at the nameplate horsepower indicated in the datasheet.
Motor Nameplate Horsepowerrange
hp
0.50.7511.52357.51015202530405060751001251502002503003504004505006007008009001000
Per drawings — the pump schedule (deferred by default)
12.1.2 The motor nameplate horsepower shall equal or exceed the pump brake horsepower at every point on the certified curve from shutoff to runout, at the liquid specific gravity indicated in this standard, without use of the service factor, and at the rated speed of a two-speed motor at each speed.
12.1.3 The motor enclosure shall be as indicated in the datasheet.
Motor Enclosureselect
Totally enclosed fan cooled, TEFC
Totally enclosed nonventilated, TENV
Open drip proof, ODP
Weather protected type I, WP-I
Explosionproof, listed for the classified location
12.1.4 Motors installed outdoors shall be furnished with a drain and breather at the low point of the frame and with a space heater, and motors installed in a location classified under NFPA 70 shall be listed for the class, division, and group of that location.
12.1.5 The motor service factor shall be as indicated in the datasheet.
Motor Service Factorrange
11.151.25
Default: Not less than 1.15
NOTE The runout condition is the one a process pump motor meets most often: a filter washwater pump into a clean filter, a transfer pump into an empty tank, or a high-service pump when a second unit drops out all move the pump far to the right of its rated point, and a motor sized to the rated point with the service factor as its margin overloads there. A 1.15 service factor is what a NEMA MG 1 open or enclosed motor carries as standard and is the thermal headroom a drive-fed motor's switching waveform consumes; a 1.0 service factor is the position of a motor that will never be loaded past nameplate, and a 1.25 factor is bought on a motor in a hot room or at altitude. (12.1.7)

12.2 Inverter Duty

12.2.1 The insulation system rating of a motor driven by a variable frequency drive shall be as indicated in the datasheet.
Motor Inverter-Duty Ratingradio
○ Inverter duty per NEMA MG 1 Part 31
○ Inverter capable per NEMA MG 1 Part 30
○ Not applicable, constant-speed or two-speed motor
Derived — the speed control selected in this standard (by default)
12.2.2 A motor driven by a variable frequency drive shall be furnished with shaft current protection by an insulated nondrive-end bearing, a shaft grounding ring, or both, as the motor manufacturer recommends for the frame size and the drive output.
NOTE The requirement follows the speed control: a drive-fed motor is inverter duty under NEMA MG 1 Part 31 unless the drive's output filter and the motor manufacturer's written acceptance make an inverter-capable motor acceptable, and a constant-speed motor needs neither. A drive's switching edge reflects at the motor terminals and can arrive at nearly twice the bus voltage, and the same edge drives a current through the bearings that pits the races within months unless it is interrupted or given a lower-impedance route. (12.2.3)

12.3 Motor Starting

12.3.1 The starting method for a constant-speed or two-speed pump motor shall be as indicated in the datasheet, with the starter furnished under Combination Motor StartersCombination and Manual Motor StartersResolves to the current adopted revision.sync/combination-motor-starters or Motor Control CentersMotor Control CentersResolves to the current adopted revision.sync/motor-control-centers by the party selected in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process.
Constant-Speed Motor Starting Methodselect
Full voltage across the line
Solid-state soft starter
Autotransformer reduced-voltage starter
Wye-delta starter
Part-winding starter
Not applicable, motor driven by a variable frequency drive
12.3.2 Where a reduced-voltage or soft starting method is indicated, the starter shall develop enough torque at the reduced voltage to accelerate the pump to full speed against a filled system within the starter's transition time, and the pump manufacturer shall confirm the pump's inertia and starting torque to the starter supplier.
NOTE Across-the-line starting is the starting of most pump motors below the size at which the utility or the plant generator objects to the inrush, and it is the simplest and the cheapest. A soft starter ramps the voltage and limits the inrush and the hydraulic surge of a sudden start, which on a long discharge main is the reason it is bought even where the supply could absorb the inrush, and it is the starter of the mid-sized high-service or raw water pump. The autotransformer, wye-delta, and part-winding starters are the electromechanical reduced-voltage starters that preceded it, and they are bought where a plant standardizes on them, where a soft starter's harmonics or its electronics in a hot room are objectionable, or at the sizes where a soft starter's cost exceeds theirs. (12.3.3)

13 Shop Coating

13.1 Exterior Shop Coating

13.1.1 Exterior ferrous surfaces of the pump, the baseplate, and the bearing frame, other than machined faces, flange faces, and the shaft, shall be shop coated with the system indicated in the datasheet.
Exterior Shop Coating Systemselect
Shop primer compatible with the field finish system
Two-coat epoxy system, shop applied
Epoxy primer and polyurethane finish, shop applied
13.1.2 Surfaces to be shop coated shall be blast-cleaned under SSPC-SP 10/NACE No. 2 before the first coat, and the dry film thickness of each coat shall be measured under SSPC-PA 2 and reported with the coating product data.
13.1.3 Where a shop primer is furnished, the field finish coats shall be applied under High Performance CoatingsHigh-Performance CoatingsResolves to the current adopted revision.sync/high-performance-coatings, and the shop primer shall be one the finish coat manufacturer accepts in writing as a compatible primer.
13.1.4 Machined surfaces, the shaft, and the coupling fits shall be protected for shipment and storage with a removable rust preventive, not with the coating system.
NOTE A shop primer under field-applied finish coats is the arrangement of a plant whose piping and equipment are all painted to one color scheme under the coatings standard after installation, and it depends on a primer the finish will adhere to and on the field painter reaching the back of the baseplate. A complete shop-applied epoxy system arrives finished, in the plant's color where the manufacturer accepts it, and takes a touch-up kit for the damage of installation; the polyurethane finish over the epoxy adds gloss and color retention where the pump sits in sunlight or where the Owner wants the equipment to look new for a decade. (13.1.5)

13.2 Stainless Steel and Nonferrous Surfaces

13.2.1 Stainless steel and bronze surfaces shall be left uncoated, and stainless steel castings and fabrications shall be pickled and passivated after machining and welding.

14 Factory Testing

14.1 Hydrostatic Test

14.1.1 Each pump casing shall be hydrostatically tested at the pressure and for the duration stated in the Casing Pressure Rating article of this standard, and the test certificate shall be furnished with the factory test reports.

14.2 Performance Test

14.2.1 Each pump furnished shall receive a factory hydraulic performance test under ANSI/HI 14.6 to the extent indicated in the datasheet, run at the rated speed with the furnished impeller, at not fewer than five points including shutoff, the rated flow, and a flow at or beyond the end of the allowable operating region.
Factory Performance Test Extentradio
● Each pump tested
○ One pump of each model and size tested, the remainder given a production run test
○ No performance test, the manufacturer's certified curve accepted
14.2.2 The performance test shall be judged against the rated flow and head to the acceptance grade indicated in the datasheet, and the test report shall state the measured flow, head, input power, efficiency, and speed at each point, corrected to the rated speed, with the tolerance band applied.
Hydraulic Performance Acceptance Grade per ANSI/HI 14.6select
Grade 1B
Grade 1E
Grade 1U
Grade 2B
Grade 2U
Grade 3B
14.2.3 The performance test shall be run with the driver indicated in the datasheet.
Performance Test Driverradio
○ The contract motor furnished with the pump
○ A calibrated shop motor, with the contract motor given its own test under the motor standard
14.2.4 Where a tested pump falls outside the tolerance band of the specified grade, the manufacturer shall correct or replace the pump and retest it at the manufacturer's cost, and the pump shall not ship until the retest is accepted.
14.2.5 Witnessing of the factory tests, the notice, and the attendance shall be as selected in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process.
NOTE Testing each pump is what most water and wastewater specifications require of a horizontal process pump, because a plant pump is bought to a duty point and the test is the only evidence it meets it; testing one of each size and running the rest is the position for a set of identical small transfer or seal water pumps, and accepting the certified curve is the position for a catalog pump below a few horsepower, whose test would cost more than the pump. (14.2.6)
NOTE The grade number sets how wide the tolerance band is and the letter sets how it is placed: Grade 1 bands are the tightest and Grade 3 the widest, a B suffix puts the band symmetrically around the guarantee, a U suffix removes the negative half so the pump may exceed the guarantee but never fall below it, and the E suffix is the bilateral grade written for the case where efficiency is the quantity guaranteed. A unilateral grade shifts all of the selection risk onto the manufacturer and its price reflects that; Grade 1B or 2B is what most plant pumps are bought to, and Grade 1U or 1E is bought on a large high-service pump whose energy cost over its life dwarfs its price. (14.2.7)
NOTE A test on the contract motor proves the assembled unit and measures the power at the motor terminals, which is the number the plant will meter; a calibrated shop motor measures the pump's shaft power more precisely and lets the test proceed before the contract motor arrives, and it leaves the assembled unit unproven until the field test. (14.2.8)

14.3 NPSH Test

14.3.1 An NPSH test under ANSI/HI 14.6 shall be performed to the extent indicated in the datasheet, establishing NPSH3 at the rated flow and at not fewer than two other flows spanning the allowable operating region.
NPSH Testradio
○ NPSH test on each pump
○ NPSH test on one pump of each model and size
○ No NPSH test, the published NPSH3 curve accepted
14.3.2 Where a tested NPSH3 exceeds the published value at any flow by more than the ANSI/HI 14.6 tolerance, the manufacturer shall correct or replace the pump, and the NPSH margin in the selection report shall be recalculated on the tested value.
NOTE An NPSH test is bought where the margin in the selection report is thin, where the suction energy is high, or where the pump draws from a long or a hot suction line, because the published NPSH3 curve is a family curve and an individual impeller can sit above it; a test on one of each size settles the family for a set of identical pumps, and accepting the published curve is the position where the NPSH available exceeds NPSH3 by a margin no casting variation could consume. (14.3.3)

14.4 Mechanical Run and Vibration

14.4.1 Each assembled pump shall be run at the factory at the rated speed long enough for the bearing temperatures to stabilize, and the direction of rotation, the freedom from abnormal noise, the seal or packing leakage, and the bearing housing vibration measured under ANSI/HI 9.6.4 shall be recorded on the test report.
14.4.2 Factory vibration shall not exceed the ANSI/HI 9.6.4 factory test allowable values for the pump type and power at any flow within the allowable operating region.
14.4.3 The factory test reports indicated in the datasheet shall be furnished before shipment.
Factory Test Reports Requiredcheckbox
☑ Hydrostatic test certificate
☑ Performance test report with the tested curve
☐ NPSH test report
☑ Mechanical run and vibration report
☐ Impeller and rotor balance record
☐ Material certificates for the casing, impeller, and shaft

15 Installation

15.1 Setting and Clearances

15.1.1 Pumps shall be set on the pads, anchors, and grout furnished under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, in the locations and orientations indicated on the process mechanical plans.
15.1.2 Clearance shall be maintained at each pump for withdrawal of the back pull-out assembly or the split-case rotor, for removal of the motor, and for access to the seal, the bearings, and the lubrication fittings, as shown on the approved shop drawings.
15.1.3 Where an overhead crane, monorail, or hoist serves the pump room, the pump and its motor shall be set so that the lifting points fall within the reach of the lifting equipment, and where none is furnished, so that a portable hoist can be positioned over each lifting point.
NOTE Overhead cranes and hoists for equipment maintenance are not yet owned by a SynC standard; this standard coordinates the pump with whatever lifting equipment the drawings show. (15.1.4)

15.2 Suction Piping Arrangement

15.2.1 Suction piping shall provide a straight, uninterrupted run immediately upstream of the pump suction connection of not less than the length indicated in the datasheet, expressed in suction pipe diameters, and shall otherwise conform to ANSI/HI 9.6.6.
Straight Suction Pipe Runrange
pipe diameters
358101520
Default: Not less than 5 pipe diameters
15.2.2 Where the straight run indicated cannot be achieved, flow conditioning shall be provided as indicated in the datasheet, and the pump manufacturer shall confirm in writing that the arrangement is acceptable for the pump furnished.
Suction Flow Conditioningradio
○ None, straight pipe run only
○ Suction diffuser at the pump suction connection
○ Straightening vanes in the suction pipe
○ Long radius elbow with its plane of curvature perpendicular to the pump shaft
15.2.3 Reducers on horizontal suction runs shall be eccentric and installed with the flat side up on a flooded suction and with the flat side down where the suction pipe slopes up to a self-priming pump.
15.2.4 Suction piping shall be arranged with no high point that can trap air between the suction source and the pump, and a suction line on a lift shall rise continuously toward the pump.
15.2.5 An elbow adjacent to the suction of a double-suction pump shall be oriented so that its plane of curvature is perpendicular to the pump shaft, and no elbow in the plane of the shaft shall be installed within the straight run indicated in the datasheet.
15.2.6 Suction and discharge piping shall be supported so that no piping weight, thermal load, or misalignment is carried by the pump connections, and the piping flanges shall mate with the pump flanges parallel and concentric before the bolts are tightened.
NOTE An elbow close to the suction delivers liquid to the impeller eye with a swirl and an uneven velocity profile that loads the vanes unequally once per revolution, and on a double-suction pump an elbow in the plane of the shaft feeds the two halves of the impeller differently and produces an axial thrust the bearings were not sized for. Five diameters is the run most pump manufacturers publish as the minimum and the one ANSI/HI 9.6.6 starts from, and a longer run is bought ahead of a large split-case pump or a pump with a high suction energy. A suction diffuser puts a straightening vane bundle and a strainer into one fitting where the room will not take the run, straightening vanes do the same inside the pipe, and the long radius elbow turned perpendicular to the shaft is the arrangement that costs nothing when the elbow is unavoidable. (15.2.7)
NOTE A concentric reducer on a horizontal run makes an air trap at its top by construction, and the pocket it holds is released into the impeller in slugs; the eccentric reducer flat side up removes the pocket on a flooded suction, and flat side down keeps a rising suction line on a lift free of a pocket at the reducer. (15.2.8)

15.3 Intake and Sump Review

15.3.1 Where a pump takes suction from a wet well, clearwell, basin, or sump, the pump manufacturer shall review the intake geometry shown on the structural and process mechanical drawings of the intake against ANSI/HI 9.8 for the pump furnished and shall report in writing any condition that does not conform, before the pump is released for fabrication.
15.3.2 The review shall address the submergence over the suction bell or the suction pipe inlet at the lowest operating level, the approach velocity and the clearances to the walls and floor, and the potential for air-entraining vortices at the maximum flow.
NOTE The Engineer of Record designs the intake to ANSI/HI 9.8 and this standard does not redesign it; the manufacturer's review exists because the pump furnished is not always the pump the intake was drawn around, and a suction pipe inlet that was adequate for one bell diameter and velocity can pull an air core at another. (15.3.3)

15.4 Discharge Piping

15.4.1 A check valve and an isolation valve shall be installed on the discharge of each pump, with the isolation valve downstream of the check valve, furnished and installed under Process Check ValvesProcess Check ValvesResolves to the current adopted revision.sync/process-check-valves and the isolation valve standard the valve schedule names.
15.4.2 The discharge gauge tap shall be read between the pump discharge and the check valve, so that the pump's own discharge pressure can be read while the pump runs.
NOTE The isolation valve downstream of the check valve is what allows the check valve itself to be serviced without draining the main, and the gauge tap upstream of the check valve is what keeps a fouled or partly open check valve from hiding inside the discharge pressure reading when the pump is compared against its curve. (15.4.3)

15.5 Coupling Alignment

15.5.1 Coupling alignment of each frame-mounted pump shall be performed by the method indicated in the datasheet, by a millwright or pump service technician qualified in that method, after the baseplate is grouted and the piping is connected.
Coupling Alignment Methodradio
● Laser alignment
○ Reverse dial indicator
○ Rim and face dial indicator
15.5.2 Straightedge and feeler gauge alignment shall not be used as the final alignment method on any pump.
15.5.3 Alignment shall be verified cold, and verified again after the pump has run long enough for the casing, the bearing housings, and the motor to reach stable operating temperature.
15.5.4 Final alignment after thermal stabilization shall be within the tolerance indicated in the datasheet.
Coupling Misalignment After Thermal Stabilizationrange
mils
12345710
15.5.5 Where the datasheet indicates no alignment tolerance, the coupling manufacturer's published tolerance for the coupling and speed furnished shall govern, and the published value shall be recorded in the alignment record beside the readings.
15.5.6 Before the final alignment is recorded, the piping flange bolts at the pump shall be loosened and the coupling readings observed, and any movement greater than 2 mils shall be corrected in the piping before the bolts are retightened.
NOTE Laser alignment is what a pump service technician brings today, reads the two shafts in one setup to a fraction of a mil, and prints the record; reverse dial indicators reach the same accuracy in experienced hands and are the method of a millwright who owns no laser; rim and face indicators are the oldest method and the one that misreads a coupling with axial float, which is why it is the least accurate of the three on a pump with a spacer coupling. (15.5.7)
NOTE The flange bolt check is the test that finds pipe strain: a pump whose shaft moves when the flange bolts are loosened is being pulled by its piping, and the alignment set against that pull is lost the day the pipe's temperature changes. (15.5.8)

16 Field Testing

16.1 Startup Verification

16.1.1 Before the first start, the Contractor shall verify the pump and motor nameplate data against the approved submittal, the suction piping arrangement against the approved drawings, the rotation with the coupling disconnected, the seal or packing flush supply at the pressure and flow the seal data requires, and the removal of any temporary startup strainer, in addition to the checkout Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process requires.
16.1.2 A self-priming pump shall be filled through its fill port before the first start, and a mechanically sealed pump shall be vented at the seal chamber or the casing vent so that the seal faces are wetted before the shaft turns.
NOTE Bumping the motor with the coupling connected to check rotation drives the pump backward and can unscrew a threaded impeller into the casing, and starting a mechanical seal dry for even a few seconds can heat-check a hard face; the two checks above are the half hour that prevents a rebuild. (16.1.3)

16.2 Field Performance Test

16.2.1 Each pump shall be field tested under the field performance test provisions of Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process by recording the suction and discharge pressures, the flow, the motor voltage, current, and speed, and the bearing housing temperatures at the rated condition and at not fewer than two other points the system can produce.
16.2.2 The total dynamic head shall be calculated from the recorded pressures with the gauge elevations and velocity heads corrected, and each point shall be plotted on the certified curve at the measured flow.
16.2.3 Where a measured point falls outside the tolerance band of the certified curve, the Contractor shall report it to the Engineer of Record and shall not proceed to acceptance until the discrepancy is resolved.
16.2.4 Variable-speed pumps shall be tested at the lowest continuous operating speed, at an intermediate speed, and at the rated speed, and any speed at which resonance occurs shall be identified and programmed as a skip band in the drive under Low Voltage Variable Frequency DrivesLow-Voltage Variable Frequency DrivesResolves to the current adopted revision.sync/low-voltage-variable-frequency-drives.
16.2.5 Where the plant cannot produce the rated condition at the time of the test, the test condition and the correction method shall be proposed to the Engineer of Record under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process before the test.
NOTE A measured point that lands to the right of the certified curve almost always means the system is less resistant than calculated rather than that the pump is over-performing, and the correction is an impeller trim or a drive setpoint rather than a throttled valve left permanently closed, which burns the same energy every hour for the life of the plant. (16.2.6)

16.3 Vibration and Seal Acceptance

16.3.1 Bearing housing vibration shall be measured at each pump and motor bearing in three planes after the pump has reached stable operating temperature, at the rated condition and at each speed tested, and shall not exceed the ANSI/HI 9.6.4 allowable values on the basis selected in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process.
16.3.2 A mechanical seal shall show no visible leakage after the first hour of operation, and a packed stuffing box shall be adjusted to the leakage rate the operation and maintenance manual states and the rate recorded.
16.3.3 Bearing housing temperatures at stable operation shall not exceed the manufacturer's published limit, and the stabilized temperatures shall be recorded in the startup report.
16.3.4 Where measured vibration, seal leakage, or bearing temperature exceeds the allowable value, the Contractor shall determine the cause and correct it, and the cost of the corrective work and the retest shall be borne by the Contractor unless the cause is shown to originate outside the Contractor's scope.
NOTE The acceptance readings become the baseline every later reading is judged against, and a reading with no speed, no flow, and no measurement point recorded beside it cannot be repeated and is not a baseline. (16.3.5)

17 Warranty

17.1 Mechanical Seal Warranty

17.1.1 The mechanical seal of each pump shall be warranted against leakage and face failure for the period indicated in the datasheet, measured from the same commencement date as the equipment warranty under Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, and where the datasheet indicates no period the seal shall carry the equipment warranty.
Mechanical Seal Warranty Periodrange
years
1235
17.1.2 Warranty coverage shall not extend to seal damage caused by dry running, by operation without the flush supply the seal data requires, or by operation outside the allowable operating region, where the manufacturer stated those limits in the submittal.
NOTE The seal is the part that fails first and most often, and a seal manufacturer that will warrant its faces for two or three years on a cartridge seal in clean water will not do so on a component seal set in the field; the warranty term the market offers is itself information about the seal selected. An exclusion for dry running or a missing flush is only enforceable where the manufacturer published the flush requirement where the Owner could see it, which is why this standard conditions it on the submittal. (17.1.3)

18 Spare Parts

18.1 Spare Parts Furnished

18.1.1 The spare parts indicated in the datasheet shall be furnished for each pump model and size installed, on the spare parts basis selected in Common Work Results ProcessCommon Work Results for Process EquipmentResolves to the current adopted revision.sync/common-work-results-process, packaged for long-term storage and labeled with the equipment numbers they serve and the manufacturer's part numbers.
Spare Parts Furnished per Pump Modelcheckbox
☑ One complete mechanical seal assembly
☐ Two complete sets of packing with lantern ring
☐ One set of casing and impeller wear rings
☐ One shaft sleeve
☐ One set of bearings
☑ One set of casing, seal chamber, and gland gaskets and O-rings
☑ One coupling element or disc pack
☐ One impeller
☐ One complete rotating element
18.1.2 The certified curve for each pump, marked with the installed impeller diameter and the measured startup operating point, shall be placed in the operation and maintenance manual, which shall otherwise conform to ANSI/HI 1.4.
NOTE A spare seal of the exact face and elastomer combination on the shelf is the difference between an afternoon outage and a week of waiting on a seal built to order, because distributors rarely stock a cartridge seal in the configuration a given pump uses; the packing set is the equivalent for a packed pump, and the wear rings, sleeve, and bearings are the overhaul kit a plant buys for a pump it intends to rebuild in its own shop. A complete rotating element is bought for a raw water or high-service pump whose outage the plant cannot tolerate for the weeks a rebuild takes. (18.1.3)

Edit this page

SynC Standards are reference material provided for informational purposes only and as a guide. They are not engineering, architectural, or legal advice and are not a substitute for the judgment of a licensed design professional. It is the responsibility of the user to determine the applicability of any standard to a specific project and to verify all requirements against the governing codes, manufacturer data, and project conditions. SynC does not render professional services and forms no professional relationship by publishing this content. Provided "as is," without warranty of any kind, including fitness for a particular purpose. See our Terms of Use for the complete terms. Moderation log.

This standard is published by SynC and licensed under Creative Commons Attribution-ShareAlike 4.0. You may share and adapt it, including commercially, provided you give credit, link to the license, indicate any changes, and license your adaptations under the same terms. Keep the attribution and notice below with any copy — it includes the warranty disclaimer the license requires you to retain.

Attribution & reuse notice — keep this with any copy:
"Horizontal Centrifugal Process Pumps." SynC Standards. Licensed under CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Source: https://synergyinconstruction.com/wiki/sync/horizontal-centrifugal-process-pumps — reference material only; not professional engineering advice and provided without warranty. Verify against governing codes and have a licensed professional review before use.