Submersible Solids-Handling Pumps
Initial publication
Showing changes from Initial revision
to Rev 1
in Submersible Solids-Handling Pumps.
+---
+title: Submersible Solids-Handling Pumps
+category: Process / Pumps
+description: >
+ When to use: Individually specified solids-handling wastewater pumps in water and wastewater treatment plants, plant influent pump stations built in a water-retaining structure, and large collection-system pump stations, read together with [[sync/common-work-results-process]], which carries the submittal register, the factory and witnessed test policy, manufacturer's field services, nameplates, spare parts basis, anchorage, and vibration and noise acceptance for every process equipment standard. Covers the pump in every arrangement the service uses: submersible in a wet well on guide rails with a discharge elbow, dry-pit submersible with an immersible motor, horizontal and vertical dry-pit solids-handling pumps with a conventional motor, and self-priming solids-handling pumps at grade, for raw sewage, primary and secondary effluent, return and waste activated sludge, plant drain, and stormwater and combined flow inside a plant. Addresses the hydraulic selection against the pump schedule, spherical solids passage, non-clog channel, vortex, screw-centrifugal, and chopper impellers, the wetted materials for grit and corrosive service, wear rings and their adjustment, tandem mechanical seals and seal leak detection, the submersible motor with its cooling, sensors, cable, and hazardous-location listing, the guide rail system, discharge elbow, and lifting chain, dry-pit and self-priming mounting, speed control interface, factory performance testing under ANSI/HI 11.6 or ANSI/HI 14.6, the field drawdown test, shop coating, warranty, and spare parts.
+ Not intended for: Centrifugal pumps for clean and raw water, finished water, service water, and process transfer, built as horizontal end-suction, split-case, and suction-lift units (see [[sync/horizontal-centrifugal-process-pumps]]); line-shaft vertical turbine pumps and submersible well pumps (see [[sync/vertical-turbine-pumps]]); progressive cavity, rotary lobe, plunger, peristaltic, and diaphragm pumps for sludge, scum, grit slurry, and thickened solids (see [[sync/positive-displacement-pumps]]); the factory-assembled site lift station with its own pumps, rails, and controls (see [[sync/packaged-pump-stations]]); building sump pumps, sewage ejectors, and grinder pumps (see [[sync/sump-and-sewage-pumps]]); building hydronic pumps (see [[sync/hvac-pumps]]), plumbing pumps (see [[sync/plumbing-pumps]]), domestic water booster pumps (see [[sync/domestic-water-booster-pumps]]), fire pumps (see [[sync/fire-pumps]]), and fuel oil pumps (see [[sync/fuel-oil-systems]]); chemical metering pumps and irrigation booster pumps, which are not yet owned by a SynC standard; the conventional motor on a dry-pit or self-priming pump (see [[sync/electric-motors]]); variable frequency drives (see [[sync/low-voltage-variable-frequency-drives]]), starters (see [[sync/combination-motor-starters]] and [[sync/motor-control-centers]]), the pump control panel (see [[sync/industrial-control-panels]]), level instruments (see [[sync/level-sensors]] and [[sync/process-instrumentation]]), and the pump control sequence (see [[sync/control-systems-integration]]); the discharge check and isolation valves (see [[sync/process-check-valves]], [[sync/resilient-seated-gate-valves]], [[sync/eccentric-plug-valves]], and [[sync/butterfly-valves]]); the process piping and its supports (see [[sync/ductile-iron-process-piping]], [[sync/steel-and-stainless-process-piping]], and [[sync/plastic-process-piping]]); the wet well or dry pit structure (see [[sync/water-retaining-concrete-structures]]); pads, anchors, and grout (see [[sync/concrete-pads]], [[sync/structural-steel-anchor-bolts]], [[sync/post-installed-anchors]], [[sync/non-shrink-grout]], and [[sync/grouted-base-plates]]); vibration isolation and seismic restraint (see [[sync/vibration-isolation-and-seismic-restraint]]); the field-applied finish coat (see [[sync/high-performance-coatings]]); and overhead cranes and hoists and electrical installations in hazardous (classified) locations, which are not yet owned by a SynC standard.
+---
+
+# Scope {toc}
+
+## Boundary of Work {toc}
+
+### This standard governs the solids-handling pump as a unit of supply: the pump end from the suction inlet through the discharge flange, the submersible or immersible motor where the pump has one, the shaft seals and the seal chamber, the power and sensor cables, the discharge elbow, guide rails, brackets, and lifting chain of a wet well installation, the stand, baseplate, and coupling of a dry-pit installation, the priming chamber of a self-priming pump, the shop coating, and the factory and field tests that prove the unit. {note}
+
+### The standard is read with [[sync/common-work-results-process]], which states once the equipment numbering and nameplates, the process equipment data sheet, the submittal procedures, manufacturer qualification and unit responsibility, site and service conditions, supports and anchorage, rotor balance and vibration and noise acceptance, the motor, drive, and control interface, guards, lubrication, the factory and witnessed test policy, manufacturer's field services, startup, field performance and acceptance testing, training, delivery and storage, warranty, and spare parts and special tools. Nothing in that standard is restated here; this standard adds what is particular to the pump. {note}
+
+### Work outside this boundary is governed by the standards named below, and this standard defers to them rather than restating their requirements: {note}
+
+- The conventional motor on a dry-pit or self-priming pump: [[sync/electric-motors]]
+- Variable frequency drives: [[sync/low-voltage-variable-frequency-drives]]; individually enclosed starters: [[sync/combination-motor-starters]]; motor control centers and the starter and drive units in them: [[sync/motor-control-centers]]
+- The pump control panel and the seal leak and thermal relays mounted in it: [[sync/industrial-control-panels]]; the control narrative, alternation, and level sequence: [[sync/control-systems-integration]]
+- Wet well level transmitters and float switches: [[sync/level-sensors]] and [[sync/process-instrumentation]]; discharge pressure gauges and transmitters: [[sync/pressure-instrumentation]]; flow meters: [[sync/flow-measurement]]
+- The discharge check valve: [[sync/process-check-valves]]; the discharge and suction isolation valves: [[sync/resilient-seated-gate-valves]], [[sync/eccentric-plug-valves]], [[sync/knife-gate-valves]], and [[sync/butterfly-valves]]
+- The process piping, its flange bolting and gaskets, its supports, and its pressure test: [[sync/ductile-iron-process-piping]], [[sync/steel-and-stainless-process-piping]], and [[sync/plastic-process-piping]]
+- The wet well, the dry pit, the wall pipes through them, and their hatches: [[sync/water-retaining-concrete-structures]]
+- Housekeeping pads, cast-in and post-installed anchors, non-shrink grout, and grouted base plates: [[sync/concrete-pads]], [[sync/structural-steel-anchor-bolts]], [[sync/post-installed-anchors]], [[sync/non-shrink-grout]], and [[sync/grouted-base-plates]]
+- Vibration isolators, inertia bases, and seismic restraint design: [[sync/vibration-isolation-and-seismic-restraint]]
+- The field-applied finish coat over the shop coating: [[sync/high-performance-coatings]]
+- Equipment identification nameplates: [[sync/mechanical-identification]]
+
+### The overhead crane, monorail, or davit that lifts the pump, and the electrical installation inside a hazardous (classified) location, including the conduit seals and the wiring methods of that location, are not yet owned by a SynC standard (the intrinsically safe cable to the pump sensors is under [[sync/instrumentation-and-control-cable]]); the lifting equipment is shown on the drawings and the classified-location installation is governed by NFPA 70 Articles 500 through 504 until a standard owns it. {note}
+
+## Pump Family Boundaries {toc}
+
+### The process pump family divides the work by what is pumped and how the pump sits in the structure, and this standard holds one part of it: the solids-handling pump, whatever its arrangement, for raw sewage, primary and secondary effluent, return and waste activated sludge, plant drain, and stormwater and combined flow. {note}
+
+- Horizontal end-suction, axially split-case double-suction, and self-priming centrifugal pumps for clean and raw water, finished water, service and seal water, plant washwater, and process transfer, including ASME B73.1 chemical process pumps: [[sync/horizontal-centrifugal-process-pumps]]
+- Line-shaft vertical turbine pumps in wet pits, cans, barrels, and deep wells, and submersible well pumps with submersible motors: [[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: [[sync/positive-displacement-pumps]]
+
+### A plant influent pump station built in a water-retaining structure with individually specified pumps is this standard; a factory-assembled site lift station furnished as one package with its basin, pumps, rails, valves, level devices, and control panel is [[sync/packaged-pump-stations]], and the line between them is drawn by how the pumps are bought, not by their size. A sewage ejector, grinder pump, or sump pump with its basin inside or beside a building, lifting into the building drainage system, is [[sync/sump-and-sewage-pumps]]. {note}
+
+### Thickened sludge, scum, and grit slurry at the concentrations a centrifugal impeller cannot move without stalling or eroding are the service of [[sync/positive-displacement-pumps]]; return and waste activated sludge at the concentrations a secondary clarifier produces are a solids-handling centrifugal service and stay here. {note}
+
+## Terms Used in This Standard {toc}
+
+### The following terms carry their Hydraulic Institute and Recommended Standards for Wastewater Facilities meanings throughout this standard: {note}
+
+- Best efficiency point (BEP): the flow at which the pump reaches its maximum efficiency at a given impeller diameter and speed
+- Preferred operating region (POR) and allowable operating region (AOR): the flow bands defined in ANSI/HI 9.6.3 relative to BEP flow
+- NPSH required (NPSHr) and NPSH available (NPSHa): the suction-side head above vapor pressure the pump needs, published by the manufacturer, and the head the installation delivers, calculated by the Engineer of Record
+- Spherical solids passage: the diameter of the largest sphere that passes through the impeller and volute without obstruction
+- Firm capacity: the capacity of the pump station with the largest single unit out of service
+- Pump-off level: the wet well level at which the control sequence stops the last running pump, and the level at which submergence and cooling are evaluated
+- Rated condition: the flow, total dynamic head, and speed listed for the pump on the pump schedule
+
+# Referenced Standards {toc}
+
+## Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
+
+## Where the Contract Documents, the adopted codes, and a referenced standard differ on the same matter, the most 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 9.8 | Rotodynamic Pumps for Pump Intake Design |
+| ANSI/HI 11.6 | Rotodynamic Submersible Pumps for Hydraulic Performance, Hydrostatic Pressure, Mechanical, and Electrical Acceptance Tests |
+| ANSI/HI 14.6 | Rotodynamic Pumps for Hydraulic Performance Acceptance Tests |
+| NEMA MG 1 | Motors and Generators |
+| NEMA 250 | Enclosures for Electrical Equipment (1000 Volts Maximum) |
+| NFPA 70 | National Electrical Code (Articles 430 and 500 through 504) |
+| NFPA 820 | Standard for Fire Protection in Wastewater Treatment and Collection Facilities |
+| UL 778 | Motor-Operated Water Pumps |
+| UL 674 | Electric Motors and Generators for Use in Division 1 Hazardous (Classified) Locations |
+| 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 A532/A532M | Abrasion-Resistant Cast Irons |
+| 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 A312/A312M | Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes |
+| ASTM F593 | Stainless Steel Bolts, Hex Cap Screws, and Studs |
+| ASTM F594 | Stainless Steel Nuts |
+| 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 |
+| GLUMRB | Recommended Standards for Wastewater Facilities (Ten States Standards) |
+
+## The Recommended Standards for Wastewater Facilities set the 3 in. spherical solids passage, the 2 ft/s force main velocity, and the firm capacity with the largest unit out of service that most state reviewers hold a pump station to; they are cited here as the design criteria the Engineer of Record is reviewed against, not as a product standard. {note}
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### In addition to the action submittals required under [[sync/common-work-results-process]], the Contractor shall submit the following for each pump before the pump is released for fabrication:
+
+- Certified performance curve for each pump at the rated speed, plotted from shutoff to runout, showing head, efficiency, brake horsepower, NPSHr, and the minimum continuous stable flow, with the rated condition, the single-pump runout condition, and the parallel-operation point marked
+- For a variable-speed pump, the family of curves at the minimum, intermediate, and rated speeds, with the system head curve overlaid and the minimum continuous speed marked
+- Selection report stating the impeller type, the spherical solids passage, the rated flow expressed as a percentage of BEP flow, the brake horsepower at runout, and the NPSH margin at the rated condition and at runout
+- The pump manufacturer's review of the wet well or sump drawings against ANSI/HI 9.8, stating the minimum submergence for the pump furnished and any intake modification the manufacturer requires
+- Motor data for a submersible or immersible motor, stating the nameplate rating, insulation system, temperature rise, service factor, starts per hour, cooling method, the hazardous-location listing with the listing agency, and the inverter-duty rating where the pump is driven by a variable frequency drive
+- Cable data stating the cable construction, the conductor sizes, the jacket material, the length furnished, and the cable entry design
+- Shaft seal data identifying the seal arrangement, the face and elastomer materials of each seal, the seal chamber oil, and the seal leak detection furnished
+- Materials of construction for the volute, impeller, wear rings or wear plate, shaft, fasteners, discharge elbow, guide rails, brackets, and lifting chain
+- Shop drawings of the discharge elbow and base, the guide rails and brackets, the upper guide bracket at the hatch frame, the lifting chain, and the dry-pit stand or baseplate, with the anchor pattern and the loads on the structure
+- Shop coating system data stating the surface preparation, the products, and the dry film thickness of each coat
+- The seal leak and thermal monitoring relay data, with the intrinsically safe barrier data where the sensors are in a classified location
+
+```datasheet
+label: Pump Action Submittals Required
+type: checkbox
+options:
+ - "Certified performance curve with rated, runout, and parallel points"
+ - "Variable-speed curve family with system head curve"
+ - "Selection report with solids passage and NPSH margin"
+ - "Manufacturer's ANSI/HI 9.8 review of the sump drawings"
+ - "Submersible motor data with listing and cooling method"
+ - "Cable data with length and entry design"
+ - "Shaft seal data"
+ - "Materials of construction"
+ - "Shop drawings of elbow, rails, lifting chain, and stand"
+ - "Shop coating system data"
+ - "Monitoring relay and barrier data"
+default:
+ - "Certified performance curve with rated, runout, and parallel points"
+ - "Selection report with solids passage and NPSH margin"
+ - "Manufacturer's ANSI/HI 9.8 review of the sump drawings"
+ - "Submersible motor data with listing and cooling method"
+ - "Cable data with length and entry design"
+ - "Shaft seal data"
+ - "Materials of construction"
+ - "Shop drawings of elbow, rails, lifting chain, and stand"
+ - "Shop coating system data"
+ - "Monitoring relay and barrier data"
+constraint: all_of
+```
+
+### The curve with the runout point marked is the submittal that finds the pump that cannot work: a solids-handling pump selected at the rated condition alone can run far to the right of its allowable region when the force main is new and clean, or when one pump is left running with the wet well drawn down, and the motor sized to the rated point is the one that trips there. {note}
+
+## Informational and Closeout Submittals {toc}
+
+### In addition to the informational and closeout submittals required under [[sync/common-work-results-process]], the Contractor shall submit the following for each pump:
+
+- Certified factory test report under the Factory Testing section of this standard, including the performance test curve, the hydrostatic test, the motor insulation resistance and the seal chamber pressure test for a submersible or immersible motor, and the sensor continuity readings
+- Field drawdown test report under the Field Testing section of this standard, with the measured pumping rate plotted on the certified curve
+- Record of the as-installed cable length, the cable routing, and the location of each cable support and each conduit seal
+- Record of the pump-off, lead-on, lag-on, and high-level elevations as set, measured from the wet well floor, and the submergence at the pump-off level
+- Seal chamber oil record stating the oil type, the fill quantity, and the inspection interval
+- Rigging and removal instructions for each pump, stating the lifting means, the pump weight, and the clearances the lift requires
+
+```datasheet
+label: Pump Informational and Closeout Submittals Required
+type: checkbox
+options:
+ - "Certified factory test report"
+ - "Field drawdown test report on the certified curve"
+ - "Cable length, routing, and conduit seal record"
+ - "Level setpoint and submergence record"
+ - "Seal chamber oil record"
+ - "Rigging and removal instructions"
+default:
+ - "Certified factory test report"
+ - "Field drawdown test report on the certified curve"
+ - "Cable length, routing, and conduit seal record"
+ - "Level setpoint and submergence record"
+ - "Seal chamber oil record"
+ - "Rigging and removal instructions"
+constraint: all_of
+```
+
+### The submergence at the pump-off level shall be recorded from the setpoints as set in the field, not copied from the design drawings.
+
+### A pump-off level moved a foot lower during startup, to buy wet well volume or to clear a floating mat, is the most common way a submersible motor that was cooled by submergence on the drawings ends up running in air; the record of the setpoints as set is what lets the next engineer see it. {note}
+
+# Quality Assurance {toc}
+
+## Pump Manufacturer Qualifications {toc}
+
+### The pump manufacturer shall have produced solids-handling pumps of the arrangement and impeller type furnished, in municipal wastewater service, for not less than the period indicated in the datasheet, which applies in place of the shorter term under [[sync/common-work-results-process]] where it is longer.
+
+```datasheet
+label: Manufacturer Experience in Wastewater Service
+type: range
+unit: years
+options:
+ min: 0
+ max: 25
+ setpoints: [0, 3, 5, 10, 15, 20, 25]
+default: 10
+constraint: min
+```
+
+### The pump manufacturer shall have an authorized service facility, with the parts stock and the test equipment for the pump furnished, within the distance of the site indicated in the datasheet.
+
+```datasheet
+label: Authorized Service Facility Distance from the Site
+type: range
+unit: miles
+options:
+ min: 50
+ max: 500
+ setpoints: [50, 100, 150, 200, 300, 500]
+constraint: max
+```
+
+### Ten years in wastewater service is the term the established solids-handling pump manufacturers clear without comment, and it is longer than the umbrella term because a wastewater pump is bought for thirty years in a service that destroys the pumps built for anything else. A service facility within a day's drive is what turns a seal change into a two-day outage instead of a two-week one, and the distance is set by what the Owner's maintenance staff can do themselves. {note}
+
+## Single-Source Supply of the Pump Assembly {toc}
+
+### The pump end, the submersible or immersible motor, the seals, the cables, the discharge elbow and base, the guide rails and brackets, the lifting chain, and the seal leak and thermal monitoring relays shall be furnished by or through the pump manufacturer as one coordinated assembly.
+
+### Where a dry-pit or self-priming pump is furnished with a conventional motor, the pump manufacturer shall select or accept the motor, and unit responsibility for the assembled unit shall be as selected under [[sync/common-work-results-process]].
+
+### The submersible motor is a part of the pump, built on the same shaft and sealed by the same seals, and no party other than the pump manufacturer can be answerable for it; the rails, elbow, and chain are furnished with the pump because the pump's own bracket has to seat on the manufacturer's own elbow, and a rail system from another source fits only by accident. {note}
+
+## Intake Design Review {toc}
+
+### The pump manufacturer shall review the wet well or sump geometry shown on [[drawing: the pump station plans and sections]] against ANSI/HI 9.8 for the pump furnished and shall state in writing the minimum submergence, the clearances from the floor and the walls, and any intake modification the manufacturer requires.
+
+### Where the manufacturer's review finds the intake geometry outside ANSI/HI 9.8 for the pump furnished, the Contractor shall report the finding to the Engineer of Record before the pump is released for fabrication, and no intake modification shall be built without the Engineer of Record's written acceptance.
+
+### Where the Engineer of Record and the pump manufacturer disagree whether the intake geometry conforms to ANSI/HI 9.8, the initial determination shall be made by the Engineer of Record.
+
+### The wet well is designed by the Engineer of Record under ANSI/HI 9.8 and built under [[sync/water-retaining-concrete-structures]] before the pump is bought, and the pump that is bought has an inlet bell diameter and a velocity the design assumed within a range. The manufacturer's review closes that range: it is the one point at which the party that knows the pump's inlet looks at the structure it will sit in, and it is cheap compared to a vortex found at startup in a wet well that is already cast. {note}
+
+# Service Conditions {toc}
+
+## Pumped Fluid {toc}
+
+### The fluid each pump handles shall be as indicated in the datasheet, and every wetted component shall be selected for that fluid, its solids, its grit, and its temperature.
+
+```datasheet
+label: Pumped Fluid
+type: select
+options:
+ - "Raw sewage, unscreened"
+ - "Raw sewage, screened"
+ - "Combined sewage or stormwater with grit"
+ - "Primary effluent"
+ - "Secondary or final effluent"
+ - "Return activated sludge"
+ - "Waste activated sludge"
+ - "Plant drain and filtrate"
+ - "Industrial wastewater"
+ - "Septage"
+```
+
+### Unscreened raw sewage carries the rags, wipes, and plastics that defeat an impeller passage, and it is the service that decides the impeller type and the solids passage; screened sewage downstream of a fine screen is the same fluid without the rag load, and it opens the selection to the higher-efficiency impellers. Combined sewage and stormwater bring grit and street sand that abrade the impeller and the wear rings, which is the service that buys hard iron. Primary and secondary effluent carry little that clogs and little that abrades, and the pump is selected on efficiency. Return and waste activated sludge are a flocculent suspension that shears and foams, and the pump is selected to move it gently at the concentration the clarifier produces. Plant drain receives whatever the plant spills, including chemicals and grit, and industrial wastewater and septage each carry what their source sends, so the materials selection for those services starts from a characterization rather than from a norm. {note}
+
+### The pump and motor shall be rated for continuous operation in liquid at the temperature indicated in the datasheet.
+
+```datasheet
+label: Pumped Liquid Temperature Rating
+type: range
+unit: °F
+options:
+ min: 60
+ max: 176
+ setpoints: [60, 86, 104, 122, 140, 176]
+default: 104
+constraint: min
+```
+
+### A 104°F liquid rating is the standard rating of a submersible wastewater motor and covers municipal sewage everywhere; a higher rating is bought for an industrial contributor with a hot discharge or for a sludge that has been heated in a digester loop, and it costs a derated motor or a cooling jacket. {note}
+
+## Pump Arrangement {toc}
+
+### The arrangement of each pump shall be as indicated in the datasheet.
+
+```datasheet
+label: Pump Arrangement
+type: select
+options:
+ - "Submersible in a wet well, on guide rails with a discharge elbow"
+ - "Submersible in a wet well, free-standing on a base stand"
+ - "Dry-pit submersible with an immersible motor, vertical"
+ - "Dry-pit submersible with an immersible motor, horizontal"
+ - "Dry-pit vertical pump with a conventional motor"
+ - "Dry-pit horizontal pump with a conventional motor"
+ - "Self-priming solids-handling pump at grade"
+```
+
+### A submersible pump on guide rails is the arrangement of most new wet wells: nothing is built above grade but a hatch, no one enters the wet well to service the pump, and the pump is lifted out on its chain and set down on a truck. It costs a motor that lives in sewage and is serviced by pulling the pump, and a wet well whose level is the only thing keeping the motor cool. A free-standing submersible on a base stand is the plant drain sump and the temporary bypass, lifted out by hand with its hose. {note}
+
+### A dry-pit submersible puts the same sealed motor in a dry well, cooled by a jacket, where it can be inspected without a lift and keeps running if the dry well floods; it is the arrangement that has displaced the conventional dry-pit pump on most new plants that have a dry well at all. A dry-pit pump with a conventional motor is serviced like any other machine, with the motor, bearings, and seal reached in place, and its motor is an ordinary motor bought from an ordinary supplier; it takes a dry well that stays dry, and a vertical unit with the motor on an elevated stand is the usual way of keeping the motor above the flood. A self-priming pump at grade needs no structure below the pump but a wet well and a suction pipe, and every part of it is at the operator's feet; it loses prime through an air leak or a long lift, and its efficiency is the lowest of the arrangements. {note}
+
+### The number of pumps in each service, the duty and standby arrangement, and the firm capacity each service provides shall be as indicated on [[drawing: the pump schedule]].
+
+## Hazardous Location {toc}
+
+### A pump, motor, cable, sensor, and junction box installed within a location classified under NFPA 820 shall be listed for the class, division, and group of that location as shown on [[drawing: the hazardous area classification drawings]].
+
+### Where the pump sensors are in a Class I, Division 1 location, the sensor circuits shall be intrinsically safe, and the pump manufacturer shall state the entity parameters of each sensor for the barrier the control panel requires.
+
+### A sewage wet well is a Class I location under NFPA 820, Division 1 unless it is continuously ventilated at the rate the standard sets, and a submersible pump in it is an electrical machine in an explosive atmosphere. The listed submersible motor exists for this condition, with its cable entry and its sensor circuits inside the listing, and the inspector who reads NFPA 820 looks for the listing mark on the pump and for the barriers in the panel. A dry well carries its own classification, which is set by its ventilation, and a dry-pit pump with a conventional motor in a Division 2 dry well needs a motor listed for it. {note}
+
+## Site Elevation and Freezing {toc}
+
+### For a dry-pit or self-priming arrangement, the NPSH available shall be calculated at the atmospheric pressure corresponding to [[parameter: altitude]], and the pump manufacturer shall confirm the NPSH margin at that pressure.
+
+### A self-priming pump installed outdoors shall have its priming chamber, its suction piping, and its discharge piping to the first valve protected from freezing at [[parameter: site-ambient-temperature-minimum]] by a heated enclosure, by heat tracing and insulation, or by both.
+
+### A self-priming pump holds a chamber of sewage between cycles by design, and that chamber freezes on a still winter night if nothing warms it; the enclosure heater is the part of a self-priming station that is cut from the budget and then bought the first February. {note}
+
+# Hydraulic Selection {toc}
+
+## Rated Condition {toc}
+
+### Each pump shall be selected and certified to deliver the rated flow at the rated total dynamic head indicated in the datasheet.
+
+```datasheet
+label: Rated Flow
+type: range
+unit: gpm
+drawing_ref: "the pump schedule"
+options:
+ min: 50
+ max: 60000
+ setpoints: [50, 100, 200, 300, 500, 750, 1000, 1500, 2000, 3000, 4000, 5000, 7500, 10000, 15000, 20000, 30000, 40000, 60000]
+default: deferred
+constraint: exact
+```
+
+```datasheet
+label: Rated Total Dynamic Head
+type: range
+unit: ft
+drawing_ref: "the pump schedule"
+options:
+ min: 10
+ max: 400
+ setpoints: [10, 15, 20, 30, 40, 50, 60, 75, 100, 125, 150, 200, 250, 300, 400]
+default: deferred
+constraint: exact
+```
+
+### The rated speed of each pump shall be as indicated in the datasheet.
+
+```datasheet
+label: Rated Speed
+type: range
+unit: RPM
+drawing_ref: "the pump schedule"
+options:
+ min: 400
+ max: 3600
+ setpoints: [400, 505, 585, 705, 870, 1170, 1750, 3500, 3600]
+default: deferred
+constraint: exact
+```
+
+### No safety factor shall be added to the rated flow or head by the Contractor or by the pump supplier; where the selection requires margin, that margin shall be established by the Engineer of Record and reflected in the pump schedule.
+
+### Speed is the selection variable that decides how a solids-handling pump wears. A slower pump has a larger impeller passage at the same flow and a lower tip speed, so it passes more and abrades less, at the price of a larger and more expensive machine; a faster pump is smaller and cheaper and reaches a high head in one stage, and it is the pump whose wear rings open in grit service. Stacked safety factors are the usual way a wastewater pump ends up far left of its best efficiency point, where a channel impeller recirculates and rags. {note}
+
+## Operating Region {toc}
+
+### The rated condition shall fall within the operating region indicated in the datasheet, determined per ANSI/HI 9.6.3 for the specific speed of the pump selected.
+
+```datasheet
+label: Required Operating Region at the Rated Condition
+type: radio
+options:
+ - "Preferred operating region per ANSI/HI 9.6.3"
+ - "Allowable operating region per ANSI/HI 9.6.3"
+default: "Preferred operating region per ANSI/HI 9.6.3"
+```
+
+### No pump shall be selected to operate beyond its allowable operating region at any condition the control sequence can produce, including a single pump running with the force main new and clean and with the wet well at the pump-off level.
+
+### Where pumps operate in parallel, each pump shall be selected on a continuously rising head-capacity characteristic from the rated condition to shutoff, and the selection report shall state the flow each pump delivers running alone.
+
+### The two ways out of the region fail differently on a solids-handling pump. Left of BEP, recirculation at the impeller eye slows the flow through the passage and lets rags settle and wrap; right of BEP, the radial load climbs, NPSHr rises steeply, and a motor sized to the rated point overloads. The runout condition is not hypothetical in a pump station: it is every new force main before it slimes, and every afternoon the second pump drops out. {note}
+
+## Speed Control and Minimum Speed {toc}
+
+### Each pump shall be driven at constant speed or at variable speed as indicated in the datasheet.
+
+```datasheet
+label: Speed Control
+type: radio
+drawing_ref: "the motor and equipment schedules and the process and instrumentation diagrams"
+options:
+ - "Constant speed"
+ - "Variable speed by a variable frequency drive"
+default: deferred
+```
+
+### Where the pump is driven at variable speed, the minimum continuous speed shall be the greater of the speed the pump manufacturer publishes for the pump furnished and the speed at which the velocity in the force main is not less than the value indicated in the datasheet.
+
+```datasheet
+label: Force Main Velocity at the Minimum Continuous Speed
+type: range
+unit: ft/s
+options:
+ min: 2
+ max: 4
+ setpoints: [2, 2.5, 3, 3.5, 4]
+default: 2
+constraint: min
+```
+
+### Where the pump is driven at variable speed, the drive shall conform to [[sync/low-voltage-variable-frequency-drives]], and the minimum speed, the skip-frequency bands, and the ramp times set at startup shall be recorded in the startup report.
+
+### A 2 ft/s force main velocity is the Recommended Standards for Wastewater Facilities floor for keeping solids in suspension, and it is the speed below which a variable-speed sewage pump deposits grit in its own force main and then has to lift it out again on the next cycle. A higher floor is set where the force main has long flat runs or carries grit-laden combined flow, and it costs the energy saving at low flow that the drive was bought for. {note}
+
+### A solids-handling pump slowed too far does not just lose head: the velocity through the impeller passage falls below what carries a rag through it, and the pump that ran clean at full speed clogs at half speed. The manufacturer's published minimum speed is set by that, and it is the reason a variable-speed sewage pump is turned down less far than a water pump. {note}
+
+## Net Positive Suction Head {toc}
+
+### The NPSH available at the pump inlet at the rated condition and at runout shall be as indicated in the datasheet.
+
+```datasheet
+label: NPSH Available at the Rated Condition
+type: range
+unit: ft
+drawing_ref: "the pump schedule"
+options:
+ min: 5
+ max: 60
+ setpoints: [5, 10, 15, 20, 25, 30, 35, 40, 50, 60]
+default: deferred
+constraint: exact
+```
+
+### The NPSH available shall exceed the NPSH required by at least the margin ratio indicated in the datasheet at the rated condition and at runout.
+
+```datasheet
+label: NPSH Margin Ratio, NPSHa Divided by NPSHr
+type: range
+options:
+ min: 1.0
+ max: 2.5
+ setpoints: [1.0, 1.1, 1.2, 1.3, 1.5, 1.75, 2.0, 2.5]
+constraint: min
+```
+
+### Where no margin ratio is indicated in the datasheet, the margin shall be established per ANSI/HI 9.6.1 for the service and the suction energy of the pump selected, and the value used shall be stated in the selection report.
+
+### A submersible pump in a wet well has its inlet below the liquid and gains NPSH from submergence, so its margin is usually comfortable and is lost only when the pump-off level is set too close to the inlet. A dry-pit pump draws through a wall pipe and a suction valve, and a self-priming pump draws through a lift, and both can be short of margin on a hot day at altitude; ANSI/HI 9.6.1 puts the margin for a wastewater pump in the lower part of its range, which is why the field is left for the engineer who has run the calculation rather than defaulted. {note}
+
+## Submergence {toc}
+
+### The submergence above the pump inlet at the pump-off level shall be not less than the value indicated in the datasheet.
+
+```datasheet
+label: Submergence Above the Pump Inlet at the Pump-Off Level
+type: range
+unit: in
+derived: "the inlet diameter and velocity of the pump furnished per ANSI/HI 9.8 and the motor cooling method selected in this standard"
+options:
+ min: 0
+ max: 96
+ setpoints: [0, 6, 12, 18, 24, 30, 36, 48, 60, 72, 96]
+default: derived
+constraint: min
+```
+
+### Where the motor is cooled by submergence, the pump-off level shall not be set below the level at which the manufacturer rates the motor for continuous operation, and the manufacturer shall state that level on the submittal.
+
+### A pump that the manufacturer certifies for continuous operation with the motor exposed shall be so certified in writing on the submittal, with the cooling method that permits it.
+
+### Submergence does two jobs on a submersible pump and the larger of the two sets the number. ANSI/HI 9.8 sets the submergence that keeps an air-entraining vortex from forming at the inlet, which rises with inlet velocity, and the motor's cooling sets the submergence that keeps the stator in liquid, which is a fixed dimension on the pump. A pump with a cooling jacket needs only the first; a pump cooled by the liquid around it needs both, and the second is the one the operator defeats by lowering the pump-off level to gain volume. {note}
+
+## Spherical Solids Passage {toc}
+
+### Each pump other than a chopper pump shall pass a spherical solid not smaller than the diameter indicated in the datasheet through the impeller and the volute.
+
+```datasheet
+label: Spherical Solids Passage
+type: range
+unit: in
+options:
+ min: 1
+ max: 8
+ setpoints: [1, 1.5, 2, 2.5, 3, 4, 5, 6, 8]
+default: 3
+constraint: min
+```
+
+### A 3 in. spherical passage is the Recommended Standards for Wastewater Facilities requirement for a raw sewage pump and the one most state reviewers require; a smaller passage is admitted for screened sewage, effluent, and sludge, where it buys efficiency, and a larger passage is specified where an unscreened influent station receives a large tributary area or where the Owner has learned what its sewer delivers. A chopper pump is rated by what it cuts rather than by what it passes, which is why the requirement does not apply to it. {note}
+
+## Pump Efficiency {toc}
+
+### The efficiency of each pump at the rated condition shall be not less than the value indicated in the datasheet, stated as wire-to-water efficiency for a pump with a submersible or immersible motor and as pump hydraulic efficiency for a pump with a conventional motor.
+
+```datasheet
+label: Efficiency at the Rated Condition
+type: range
+unit: '%'
+options:
+ min: 30
+ max: 85
+ setpoints: [30, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85]
+constraint: min
+```
+
+### Where the datasheet indicates no efficiency, the certified efficiency at the rated condition shall be reported for each pump and evaluated against the manufacturer's published BEP efficiency for that pump.
+
+### No single efficiency spans this standard: a 3 in. passage single-vane impeller at 200 gpm and a 24 in. dry-pit pump at 20,000 gpm are twenty points apart at their best points, and a vortex impeller gives up another ten to fifteen for its clog resistance. The submersible pump is tested wire-to-water under ANSI/HI 11.6 because its motor cannot be separated from it, and a wire-to-water number is not comparable to a hydraulic number for a pump whose motor is tested apart. {note}
+
+# Pump Construction {toc}
+
+## Impeller Type {toc}
+
+### The impeller of each pump shall be of the type indicated in the datasheet.
+
+```datasheet
+label: Impeller Type
+type: select
+options:
+ - "Single-vane non-clog channel, enclosed"
+ - "Two-vane or multi-vane non-clog channel, enclosed"
+ - "Semi-open self-cleaning channel with a relief groove or adaptive clearance"
+ - "Recessed vortex"
+ - "Screw-centrifugal"
+ - "Chopper with cutting elements at the suction"
+```
+
+### A single-vane channel impeller has the largest passage for its diameter and passes the 3 in. solid at the smallest pump, at an efficiency in the middle of the range and with a hydraulic unbalance that the manufacturer balances by casting. A two-vane or multi-vane channel impeller is the most efficient solids-handling impeller and the one most plant pumps above the smallest sizes run, and its passage is what the rag load has to get through. A semi-open self-cleaning impeller runs against a wear plate with a relief groove that cuts or sweeps a rag off the leading edge, and it holds its efficiency in a wipe-laden sewer where an enclosed channel impeller clogs, at the cost of a clearance that has to be kept adjusted. {note}
+
+### A recessed vortex impeller sits out of the flow path so the solid passes through the volute without touching the vane, and it is the impeller for stringy, abrasive, and fragile solids, at an efficiency ten to twenty points below a channel impeller. A screw-centrifugal impeller moves the fluid along a single long vane with low shear and a large passage, and it is the impeller for activated sludge and for solids that must not be broken up. A chopper impeller cuts whatever reaches the suction against a stationary cutter bar and is specified where the rag load has defeated a channel impeller, where a grinder is too small, and in scum and septage service; it costs energy and cutter wear and it is the last resort rather than the first. {note}
+
+### The impeller shall be keyed to the shaft and secured against loosening in the direction of rotation and against reverse rotation on shutdown.
+
+### The impeller shall be dynamically balanced to ISO 21940-11 grade G6.3 or finer, and the balance record shall be available to the Engineer of Record on request.
+
+## Chopper and Cutting Elements {toc}
+
+### Requirements in this article apply where a chopper impeller is selected in the datasheet.
+
+### The cutter bar, the impeller cutting edges, and any upper or back cutter shall be of hardened stainless steel with a hardness not less than the value indicated in the datasheet.
+
+```datasheet
+label: Cutting Element Hardness
+type: range
+unit: HRC
+options:
+ min: 45
+ max: 65
+ setpoints: [45, 50, 55, 58, 60, 65]
+constraint: min
+```
+
+### The cutter bar shall be replaceable, and the cutting clearance between the impeller and the cutter bar shall be adjustable from outside the pump without removing the impeller.
+
+### Cutting elements worn beyond the manufacturer's service limit within the warranty period shall be replaced under the Warranty section of this standard.
+
+### Chopper manufacturers harden their cutters to the high fifties and low sixties on the Rockwell C scale, and the number is a trade between edge life and brittleness: a harder cutter holds its edge longer in rag service and chips sooner on the rock or the bolt that arrives with the rags. The field is left for the engineer who knows the sewer, and the manufacturer's published hardness governs where none is indicated. {note}
+
+## Volute and Casing Material {toc}
+
+### The volute and the casing of each pump shall be of the material indicated in the datasheet.
+
+```datasheet
+label: Volute and Casing Material
+type: select
+options:
+ - "Cast iron"
+ - "Ductile iron"
+ - "Stainless steel, Type 316"
+ - "Duplex stainless steel"
+default: "Cast iron"
+```
+
+### Cast iron castings shall conform to ASTM A48/A48M, Class 30 or higher.
+
+### Ductile iron castings shall conform to ASTM A536, grade 65-45-12 or higher.
+
+### Stainless steel castings shall conform to ASTM A743/A743M grade CF8M for Type 316 and to ASTM A890/A890M for duplex grades.
+
+### Cast iron is the solids-handling pump as sold and lasts in municipal sewage for the life of the machine under its epoxy; ductile iron carries the same service at a lighter section and survives the impact that cracks gray iron, and it is the casing a manufacturer offers where the pump is large or the pressure is high. A stainless casing is specified where the fluid attacks coated iron, with an industrial contributor, brackish infiltration, or a chemical spill reaching the plant drain, and a duplex casing adds strength and chloride resistance for seawater and brine at several times the cost of iron. {note}
+
+## Impeller Material {toc}
+
+### The impeller of each pump shall be of the material indicated in the datasheet.
+
+```datasheet
+label: Impeller Material
+type: select
+options:
+ - "Cast iron"
+ - "Ductile iron"
+ - "High-chrome white iron"
+ - "Stainless steel, Type 316"
+ - "Duplex stainless steel"
+default: "Cast iron"
+```
+
+### High-chrome white iron impellers shall conform to ASTM A532/A532M Class III Type A.
+
+### A cast iron impeller runs for decades in domestic sewage and is the impeller shipped on most pumps; ductile iron takes the impact of a hard solid without cracking a vane and is the usual upgrade at no great cost. High-chrome white iron is the abrasion material for grit-laden stormwater, combined sewage, and headworks service, with a hardness that grit cannot cut, and it cannot be welded or machined once cast, so a damaged vane is a new impeller. A stainless impeller resists corrosion rather than abrasion and is paired with a stainless casing in a corrosive service; a duplex impeller does both and is the impeller of seawater and brine. {note}
+
+## Wear Rings and Clearance {toc}
+
+### The running clearance between the impeller and the casing shall be formed as indicated in the datasheet.
+
+```datasheet
+label: Wear Ring Arrangement
+type: radio
+options:
+ - "Renewable casing wear ring only"
+ - "Renewable wear rings on both the casing and the impeller"
+ - "Replaceable suction wear plate"
+ - "No renewable ring or plate, clearance formed by the casing and impeller"
+```
+
+### An enclosed channel impeller runs inside a casing ring, and a renewable casing ring alone is what most solids-handling pumps carry; a ring on the impeller as well doubles the renewable surface and is specified on large pumps and in grit service where both faces wear. A semi-open or screw-centrifugal impeller runs against a flat wear plate rather than inside a ring, and the plate is the renewable part. A pump with no renewable ring or plate recovers its clearance only by a new impeller or a new casing, which is acceptable on a small pump that is replaced rather than rebuilt. {note}
+
+### Wear rings and wear plates shall be of the material indicated in the datasheet, secured against rotation, and renewable without machining the casing or the impeller.
+
+```datasheet
+label: Wear Ring and Wear Plate Material
+type: select
+options:
+ - "Hardened stainless steel"
+ - "Stainless steel, Type 316"
+ - "High-chrome white iron"
+ - "Bronze"
+ - "Not applicable, no renewable ring or plate"
+```
+
+### Where a metallic ring runs against a metallic ring, the two shall differ in hardness so that the pair does not gall on contact.
+
+### A hardened stainless ring is the ring most solids-handling pumps carry, hard enough to resist grit and stainless enough not to rust shut during a long idle; a Type 316 ring is specified in a corrosive service and wears faster in grit. High-chrome white iron is the ring and plate material of grit and headworks service, paired with a white iron impeller. Bronze is the ring of an older dry-pit pump and of effluent service, soft enough to take the wear in place of the impeller and the easiest to replace. {note}
+
+### The impeller clearance shall be adjustable as indicated in the datasheet.
+
+```datasheet
+label: Impeller Clearance Adjustment
+type: radio
+options:
+ - "External adjustment without disassembly"
+ - "Adjustment by shims at disassembly"
+ - "Not applicable, enclosed impeller running in wear rings"
+```
+
+### A semi-open impeller loses its performance as the clearance to the wear plate opens, and a pump whose clearance is restored by turning an external adjusting screw is kept at its curve by the operator; one that is shimmed at disassembly is kept at its curve by the shop, which means it is not. An enclosed impeller sets its clearance by the ring and has nothing to adjust. {note}
+
+### The wear ring clearance is the only path from the discharge side of the impeller back to the suction, and as grit opens it the pump recirculates a rising share of its own flow. The head-capacity curve barely moves while the drawdown rate falls, which is why the loss is found by the drawdown test and not by the pressure gauge. {note}
+
+## Shaft and Bearings {toc}
+
+### The shaft shall be of the material indicated in the datasheet, sized so that the deflection at the lower seal faces stays within the seal manufacturer's limit across the allowable operating region.
+
+```datasheet
+label: Shaft Material
+type: select
+options:
+ - "Stainless steel, Type 420 or Type 431"
+ - "Stainless steel, 17-4 PH"
+ - "Stainless steel, Type 316"
+ - "Duplex stainless steel"
+ - "Carbon steel with a stainless steel sleeve through the seal"
+default: manufacturer
+```
+
+### The shaft grade furnished shall be stated on the submittal and on the process equipment data sheet.
+
+### Stainless steel shafts shall conform to ASTM A276/A276M for the grade furnished.
+
+### A martensitic stainless shaft of Type 420 or 431 is the submersible pump shaft as the manufacturers build it, hard enough to carry the seal without a sleeve and stainless enough for sewage, and 17-4 PH is the same idea at a higher strength for the largest pumps. A Type 316 shaft resists chlorides that pit a martensitic grade and is the shaft of the corrosive service, at lower strength; a duplex shaft gives both. A carbon steel shaft with a stainless sleeve through the seal is the conventional dry-pit pump shaft, where the sleeve is the wear part and the shaft never sees the fluid. The manufacturer's standard is accepted because each builds its pump around one grade. {note}
+
+### Bearings shall be antifriction bearings selected for a rating life not less than the value indicated in the datasheet, calculated at the rated condition.
+
+```datasheet
+label: Bearing Rating Life at the Rated Condition
+type: range
+unit: hours
+options:
+ min: 17500
+ max: 100000
+ setpoints: [17500, 25000, 40000, 50000, 100000]
+default: 50000
+constraint: min
+```
+
+### Bearings shall be lubricated as indicated in the datasheet.
+
+```datasheet
+label: Bearing Lubrication
+type: radio
+options:
+ - "Sealed bearings, permanently lubricated"
+ - "Grease-lubricated through external fittings"
+ - "Oil-lubricated"
+```
+
+### A 50,000 hour rating life is the figure most wastewater pump specifications carry and most submersible manufacturers meet at the rated condition, which is a little under six years of continuous running; a 100,000 hour life is bought on the largest pumps, where the bearing is a day's work to change. The rating is calculated at one point, and a pump that spends its life at runout carries a radial load the calculation did not see. {note}
+
+### A submersible motor is sealed and its bearings are permanently lubricated, because there is no one to grease them and no way to reach a fitting under water; a grease fitting on a submersible is reached only at overhaul. A dry-pit pump with a conventional motor carries regreasable bearings, which last indefinitely and are destroyed by over-greasing, and the largest dry-pit pumps carry oil-lubricated bearings with a sight glass. {note}
+
+## Fasteners and Lifting Attachments {toc}
+
+### Fasteners exposed to the pumped fluid or to the wet well atmosphere, and every fastener of the discharge elbow, guide rails, brackets, and lifting chain, shall be stainless steel conforming to ASTM F593 and ASTM F594, Type 316.
+
+### Each pump shall be furnished with a lifting bail or eye, integral with or bolted to the pump, rated for the weight of the pump and motor assembly and positioned so the pump hangs level on its guide rails or its sling.
+
+# Shaft Sealing {toc}
+
+## Submersible and Immersible Motor Seals {toc}
+
+### Requirements in this article apply where a submersible or dry-pit submersible arrangement is selected in the datasheet.
+
+### The shaft between the pumped fluid and the motor shall be sealed by the arrangement indicated in the datasheet.
+
+```datasheet
+label: Submersible Shaft Seal Arrangement
+type: radio
+options:
+ - "Tandem mechanical seals in an oil-filled chamber"
+ - "Double mechanical seals, back to back, in an oil-filled chamber"
+ - "Single mechanical seal with an oil-filled chamber"
+default: "Tandem mechanical seals in an oil-filled chamber"
+```
+
+### Tandem seals, a lower seal facing the pumped fluid and an upper seal facing the motor with an oil chamber between them, are the arrangement of nearly every solids-handling submersible pump: the lower seal takes the sewage and the upper seal keeps the motor dry when the lower one fails, and the oil between them is what the leak sensor watches. Back-to-back seals share one set of faces against the fluid and are the arrangement of a few manufacturers' designs. A single seal with an oil chamber is the small pump's arrangement, and a failed seal there is a flooded motor. {note}
+
+### The lower seal shall be independent of the direction of rotation and shall run in the pumped fluid without an external flush.
+
+### The faces of the lower seal shall be of a combination indicated in the datasheet.
+
+```datasheet
+label: Lower Seal Face Combination
+type: checkbox
+options:
+ - "Silicon carbide against silicon carbide"
+ - "Tungsten carbide against tungsten carbide"
+ - "Silicon carbide against tungsten carbide"
+default:
+ - "Silicon carbide against silicon carbide"
+ - "Tungsten carbide against tungsten carbide"
+constraint: any_of
+```
+
+### The faces of the upper seal shall be of carbon, silicon carbide, or tungsten carbide against ceramic, silicon carbide, or tungsten carbide, and the combination furnished shall be stated on the submittal.
+
+### Seal elastomers shall be of the material indicated in the datasheet and shall be compatible with the pumped fluid and the seal chamber oil.
+
+```datasheet
+label: Seal Elastomer
+type: select
+options:
+ - "Fluoroelastomer, FKM"
+ - "Nitrile, NBR"
+ - "EPDM"
+ - "Perfluoroelastomer, FFKM"
+```
+
+### The lower seal lives in grit, and hard-on-hard faces are the only ones that survive it: a carbon face embeds every grain of sand and laps itself away. Silicon carbide and tungsten carbide are both standard on the lower seal, and the manufacturers divide between them; both are accepted so that no manufacturer is excluded for its standard face, and the project narrows the list where it has a reason. Fluoroelastomer and nitrile both serve municipal sewage, with fluoroelastomer taking the solvents and the heat that nitrile does not and nitrile taking the ammonia and the lower cost; EPDM is the elastomer for a hot or a caustic service and is attacked by any oil, including the seal chamber oil unless the oil is chosen for it, and a perfluoroelastomer is bought for the industrial fluid nothing else resists. {note}
+
+### The seal chamber shall be filled at the factory with the oil the manufacturer specifies, and the chamber shall be fitted with fill and drain plugs reachable with the pump removed from the wet well without disassembly of the pump.
+
+### Seal leak detection shall be furnished as indicated in the datasheet, with each sensor wired to the control panel through the pump cable.
+
+```datasheet
+label: Seal Leak and Moisture Detection
+type: checkbox
+options:
+ - "Moisture sensor in the seal oil chamber"
+ - "Moisture sensor in the motor stator housing"
+ - "Moisture sensor in the terminal or junction chamber"
+default:
+ - "Moisture sensor in the seal oil chamber"
+ - "Moisture sensor in the motor stator housing"
+constraint: all_of
+```
+
+### A seal leak shall be indicated at the control panel as an alarm and shall not stop the pump unless the control narrative under [[sync/control-systems-integration]] directs otherwise.
+
+### A sensor in the oil chamber sees water the moment the lower seal passes it, while the upper seal is still holding, and that is the alarm an operator has a week to act on. A sensor in the stator housing sees the water the upper seal has let through, which is the alarm the motor has hours to live on, and the two together tell the operator which seal failed. A sensor in the terminal chamber catches water wicking down a damaged cable, which neither of the others sees. Stopping a pump on a seal leak alarm is a choice the plant makes in its narrative, and most plants run the pump to the next planned pull rather than lose a duty pump to a damp sensor. {note}
+
+## Dry-Pit Conventional Pump Seals {toc}
+
+### Requirements in this article apply where a dry-pit arrangement with a conventional motor or a self-priming arrangement is selected in the datasheet.
+
+### The shaft seal shall be of the arrangement indicated in the datasheet.
+
+```datasheet
+label: Dry-Pit and Self-Priming Shaft Seal Arrangement
+type: select
+options:
+ - "Single mechanical seal with external seal water flush"
+ - "Single cartridge mechanical seal with external seal water flush"
+ - "Split mechanical seal"
+ - "Tandem mechanical seals in an oil-filled chamber"
+ - "Compression packing with a lantern ring and seal water"
+```
+
+### A single mechanical seal with a clean external flush is the dry-pit solids-handling pump seal of most plants, and a cartridge seal is the same seal pre-set on its own sleeve so a maintenance crew installs it without measuring spring compression. A split seal is changed without pulling the coupling or the impeller, which decides the question on a large pump that is maintained in place. A tandem seal in an oil chamber needs no seal water at all and is the seal of the self-priming pump and of a dry-pit pump where seal water is not run. Compression packing is still in service on large older pumps where a controlled drip is tolerable and a seal outage is not, and it needs the seal water and the drain that go with it. {note}
+
+### Where a seal water flush is furnished, the seal water shall be supplied from the source indicated in the datasheet, through a solenoid valve opened with the pump run command, a flow indicator, and a pressure regulator set to the pressure the seal manufacturer requires above the seal chamber pressure.
+
+```datasheet
+label: Seal Water Source
+type: select
+options:
+ - "Plant service water"
+ - "Plant effluent water"
+ - "Potable water through a reduced-pressure backflow preventer or an air gap"
+ - "Not applicable, seal requires no external water"
+```
+
+### Where a seal water flush is furnished, a loss of seal water flow shall be alarmed at the control panel, and the pump shall be stopped on loss of seal water flow where the control narrative under [[sync/control-systems-integration]] directs it.
+
+### Plant service water is the seal water most plants run, clean enough for a seal and already piped through the gallery. Plant effluent water is the same at a plant that has no service water system and carries the solids the effluent carries, which a seal tolerates only with a strainer ahead of it. Potable water is the cleanest and the most expensive, and the cross-connection it creates with sewage is the reason it is admitted only through a reduced-pressure backflow preventer or an air gap. {note}
+
+### Where compression packing is furnished, the stuffing box shall be drained to the dry well sump, and the operation and maintenance manual shall state the leakage rate the packing requires for cooling.
+
+# Submersible and Immersible Motor {toc}
+
+## Motor Rating {toc}
+
+### Requirements in this section apply to the submersible or immersible motor furnished as part of the pump; the conventional motor on a dry-pit or self-priming pump is governed by [[sync/electric-motors]], and the enclosure, service factor, duty, and inverter-duty requirement for that motor are as stated in this section.
+
+### The motor shall be rated as indicated in the datasheet.
+
+```datasheet
+label: Motor Nameplate Horsepower
+type: range
+unit: hp
+drawing_ref: "the pump schedule"
+options:
+ min: 1
+ max: 1000
+ setpoints: [1, 1.5, 2, 3, 5, 7.5, 10, 15, 20, 25, 30, 40, 50, 60, 75, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 1000]
+default: deferred
+constraint: exact
+```
+
+```datasheet
+label: Motor Supply Voltage
+type: range
+unit: V
+drawing_ref: "the electrical one-line diagram and the motor schedule"
+options:
+ min: 208
+ max: 4160
+ setpoints: [208, 230, 460, 480, 575, 2300, 4160]
+default: deferred
+constraint: exact
+```
+
+```datasheet
+label: Motor Supply Phase
+type: radio
+drawing_ref: "the electrical one-line diagram and the motor schedule"
+options:
+ - "Single phase, 1Φ"
+ - "Three phase, 3Φ"
+default: deferred
+```
+
+### For the non-overloading requirement under [[sync/common-work-results-process]], the operating range of a solids-handling pump is the full published curve from shutoff to runout at the rated speed, evaluated at the specific gravity of the pumped fluid.
+
+### The motor service factor shall be as indicated in the datasheet, and the service factor shall not be used as capacity in the non-overloading evaluation.
+
+```datasheet
+label: Motor Service Factor
+type: range
+options:
+ min: 1.0
+ max: 1.25
+ setpoints: [1.0, 1.15, 1.25]
+default: 1.15
+constraint: min
+```
+
+### The motor shall be rated for not fewer than the starts per hour indicated in the datasheet, evenly spaced, at the rated load.
+
+```datasheet
+label: Motor Starts per Hour
+type: range
+unit: starts/h
+options:
+ min: 4
+ max: 30
+ setpoints: [4, 6, 10, 15, 20, 30]
+default: 10
+constraint: min
+```
+
+### A submersible wastewater motor is built with a 1.15 service factor as standard and the factor is thermal headroom, not capacity; a motor that needs its service factor at runout is a motor sized to the rated point. Ten starts per hour is the rating most manufacturers publish for a large motor and the one a wet well sized under the Recommended Standards for Wastewater Facilities stays under; fifteen is the small motor's rating and is bought where the wet well is small and the cycle short, and a motor that is asked to start more often than its rating fails by winding heat rather than by anything a protective device sees. {note}
+
+## Insulation and Thermal Protection {toc}
+
+### The motor insulation system shall be of a class indicated in the datasheet under NEMA MG 1, with a temperature rise at rated load in liquid at the rated temperature not exceeding the Class B rise.
+
+```datasheet
+label: Motor Insulation Class
+type: checkbox
+options:
+ - "Class B"
+ - "Class F"
+ - "Class H"
+default:
+ - "Class F"
+ - "Class H"
+constraint: any_of
+```
+
+### Stator windings shall be moisture resistant, and the stator shall be removable from the motor housing for rewinding without destroying the housing.
+
+### Thermal sensors shall be embedded in the stator windings as indicated in the datasheet and wired to the control panel through the pump cable to stop the pump on winding overtemperature.
+
+```datasheet
+label: Winding Thermal Sensors
+type: select
+options:
+ - "Bimetallic thermal switches, one in each phase"
+ - "PTC thermistors, one in each phase"
+ - "Resistance temperature detectors, one in each phase"
+ - "Bimetallic thermal switches and resistance temperature detectors"
+default: "Bimetallic thermal switches, one in each phase"
+```
+
+### Bimetallic switches in series in each phase are what every submersible manufacturer ships, a dry contact that opens at the trip temperature and needs no relay but the one in the starter circuit. A thermistor trips at the same temperature through a relay that also sees an open sensor circuit. A detector in each phase reads the winding temperature continuously, which lets the control system trend it and alarm before the trip, and it is bought on the large motor whose rewind costs more than the instrumentation; a motor with both keeps the trip in a switch and the trend in the detector. {note}
+
+### Additional condition monitoring sensors shall be furnished as indicated in the datasheet.
+
+```datasheet
+label: Condition Monitoring Sensors
+type: checkbox
+options:
+ - "Bearing temperature sensor in the lower bearing"
+ - "Bearing temperature sensor in the upper bearing"
+ - "Vibration sensor in the motor housing"
+ - "Stator winding temperature detectors for trending"
+constraint: all_of
+```
+
+## Motor Cooling {toc}
+
+### The motor shall be cooled by the method indicated in the datasheet, and the manufacturer shall state the submergence or the dry-well condition at which the motor is rated for continuous operation.
+
+```datasheet
+label: Motor Cooling Method
+type: select
+options:
+ - "Cooled by the pumped liquid surrounding the motor housing, submerged"
+ - "Closed-loop cooling jacket with an internal coolant circulated by the pump shaft"
+ - "Cooling jacket fed by the pumped liquid from the volute"
+ - "Cooling jacket fed by an external clean water supply"
+ - "Air-cooled conventional motor, not submerged"
+```
+
+### A motor cooled by the liquid around it is the simplest submersible and the one most wet well pumps are, and it is rated for continuous operation only with the stator submerged; what it costs is a pump-off level that cannot be set below the motor. A closed-loop jacket circulates a glycol or oil coolant through the motor housing and rejects the heat to the pumped liquid through the jacket wall, so the motor runs continuously in air, in a dry pit, or with the wet well drawn to the floor, and the coolant is one more fluid to check. A jacket fed by the pumped liquid is the same idea with sewage as the coolant, and it fouls where the sewage carries grease and fiber. A jacket fed by clean external water is the dry-pit pump at a plant that has service water and does not want sewage in its jacket. A conventional air-cooled motor is the dry-pit pump of the ordinary kind. {note}
+
+### Where the motor is cooled by a jacket fed by the pumped liquid, the jacket shall be furnished with flush and drain connections, and the cleaning interval shall be stated in the operation and maintenance manual.
+
+### A dry-pit submersible motor shall be rated for continuous operation at the rated load in air and shall be rated for continuous operation submerged to the depth the dry well can flood, as shown on [[drawing: the pump station plans and sections]].
+
+## Hazardous-Location Listing {toc}
+
+### The motor, its cable entry, and its sensor circuits shall carry the listing indicated in the datasheet.
+
+```datasheet
+label: Motor Hazardous-Location Listing
+type: radio
+options:
+ - "Explosion-proof, listed for Class I, Division 1, Groups C and D"
+ - "Listed for Class I, Division 2"
+ - "Not listed for a classified location"
+derived: "the area classification of the pump location on the hazardous area classification drawings, per NFPA 820"
+default: derived
+```
+
+### An explosion-proof submersible motor shall be listed under UL 674 or by FM Approvals for the location, with the pump cable and the cable entry included in the listing.
+
+### A motor listed for Class I, Division 1 is built with the flame paths, the cable entry, and the sensor circuits inside the listing, and a listing on the motor alone with a field-fitted cable gland is not a listed assembly. The listing follows the classification on the drawings, which is why the field derives rather than selects; an unclassified stormwater wet well and a ventilated dry well are the two places a plant pump needs no listing. {note}
+
+## Power and Sensor Cable {toc}
+
+### Each pump shall be furnished with power and sensor cable of the construction indicated in the datasheet, continuous without splice from the motor to the junction box outside the wet well, and of a length not less than the value indicated in the datasheet.
+
+```datasheet
+label: Cable Construction
+type: radio
+options:
+ - "Separate power cable and sensor cable"
+ - "Single composite cable carrying power and sensor conductors"
+```
+
+```datasheet
+label: Cable Length per Pump
+type: range
+unit: ft
+drawing_ref: "the pump station plans and sections"
+options:
+ min: 25
+ max: 500
+ setpoints: [25, 33, 50, 65, 75, 100, 150, 200, 300, 500]
+default: deferred
+constraint: min
+```
+
+### The cable shall be listed for submersible pump service and for the hazardous-location listing of the motor, with an oil- and water-resistant jacket, and the cable jacket material and the conductor sizes shall be stated on the submittal.
+
+### The cable entry into the motor shall be sealed by a design that prevents water from wicking along the conductors into the motor on a damaged jacket, by a compression grommet with the conductors individually sealed, by an epoxy-potted entry, or by both, and the entry shall carry a strain relief that holds the cable weight off the seal.
+
+### The cable shall be supported in the wet well so that it carries no load at the entry, with stainless steel cable grips at the hatch frame and at intervals the manufacturer publishes, and it shall not be clamped to the guide rails.
+
+### A separate sensor cable keeps the low-voltage sensor circuits out of the power cable and is the construction that an intrinsically safe sensor circuit in a Division 1 wet well is simplest to run; a composite cable has one entry to seal, one grip to fit, and one cable to pull, and is the construction of the smaller pumps. Cable length is set by the depth of the wet well and the run to the junction box, and a cable ordered short is a splice in the wet well, which no listing covers. {note}
+
+## Monitoring Relays {toc}
+
+### The seal leak and winding thermal monitoring relays the pump sensors require shall be furnished by the party indicated in the datasheet, for mounting in the pump control panel under [[sync/industrial-control-panels]].
+
+```datasheet
+label: Seal Leak and Thermal Monitoring Relays Furnished By
+type: radio
+options:
+ - "The pump manufacturer, shipped loose for mounting in the control panel"
+ - "The control panel manufacturer, to the pump manufacturer's sensor specification"
+default: "The pump manufacturer, shipped loose for mounting in the control panel"
+```
+
+### Where the sensors are in a Class I, Division 1 location, the intrinsically safe barrier or the listed intrinsically safe relay for each sensor circuit shall be furnished with the monitoring relays and shall be matched to the sensor entity parameters the pump manufacturer states.
+
+### The seal leak relay reads a resistance that each manufacturer sets differently, and the relay that matches the sensor is the pump manufacturer's; shipping it loose with the pump is what most pump stations do and what keeps the pump manufacturer answerable when the alarm is wrong. A panel builder sources the relay only where the Owner standardizes its panels and will carry the mismatch itself. {note}
+
+## Inverter Duty and Starting {toc}
+
+### Where the pump is driven by a variable frequency drive, the motor shall be rated for inverter duty under NEMA MG 1 Part 31, and the pump manufacturer shall confirm the cable length between the drive and the motor against the drive's output voltage rise limits.
+
+### Where the pump is driven by a variable frequency drive, the motor current at the rated condition shall not exceed the nameplate full-load current.
+
+### Where the pump is started at constant speed, the starting method under [[sync/combination-motor-starters]] or [[sync/motor-control-centers]] shall develop the torque to accelerate the pump to full speed against the system within the time the motor's starts-per-hour rating allows.
+
+### The submersible motor is at the end of the longest motor cable in the plant, from a drive in the electrical room down the wet well to the motor, and the voltage overshoot at the motor terminals rises with that length; the pump manufacturer, who built the cable into the motor, is the party who can say whether the drive needs an output filter under [[sync/low-voltage-variable-frequency-drives]]. {note}
+
+# Wet Well Installation Hardware {toc}
+
+## Discharge Elbow and Base {toc}
+
+### Requirements in this section apply where a submersible wet well arrangement on guide rails is selected in the datasheet.
+
+### Each pump shall be furnished with a discharge elbow and base, permanently anchored to the wet well floor, with a flanged outlet to the discharge piping and a seating face on which the pump seats and seals by its own weight, so that the pump is installed and removed without bolting and without a person entering the wet well.
+
+### The discharge elbow shall be of cast iron or ductile iron, coated with the same system as the pump, with Type 316 stainless steel anchor bolts, and its flange shall conform to ASME B16.1 Class 125 or ASME B16.42 Class 150.
+
+### The seating between the pump discharge and the elbow shall be a machined metal-to-metal face, a replaceable sealing ring, or both, and the sealing ring, where furnished, shall be replaceable without removing the elbow from the floor.
+
+### The elbow base shall carry the pump weight, the discharge reaction, and the load of the pump being seated, and the anchor pattern and loads shall be shown on the shop drawings for the anchorage under [[sync/common-work-results-process]].
+
+### The elbow is the one part of a guide rail installation that is cast into the station for its life, and a pump from any other source has to be made to seat on it; that is why the elbow, the pump bracket, and the rails come from one manufacturer, and why a replacement pump decades later is bought to fit the elbow. A seating face that leaks does not fail the pump, it recirculates a share of its flow into the wet well and shows up as a drawdown rate below the curve. {note}
+
+## Guide Rails and Brackets {toc}
+
+### Each pump shall be furnished with the guide rail configuration indicated in the datasheet, extending from the discharge elbow to an upper guide bracket at the hatch frame, so that the pump is lowered along the rails and seated on the elbow by its own weight.
+
+```datasheet
+label: Guide Rail Configuration
+type: radio
+options:
+ - "Two parallel guide rails"
+ - "Single guide rail or bar"
+ - "Guide cable system"
+default: "Two parallel guide rails"
+```
+
+### Two parallel pipe rails are the system most plant pumps ride, stiff enough to guide a heavy pump to its seat without twisting; a single rail or bar is the system of a few manufacturers' designs and of the smaller pumps, with one bracket and one rail to buy, and a guide cable is the lightest system, used where the hatch is small and the pump light, and the one that a stuck pump turns into a lift that cannot be guided. {note}
+
+### Guide rails, the upper guide bracket, and intermediate brackets shall be of the material indicated in the datasheet.
+
+```datasheet
+label: Guide Rail and Bracket Material
+type: radio
+options:
+ - "Type 304 stainless steel"
+ - "Type 316 stainless steel"
+ - "Hot-dip galvanized steel"
+```
+
+### Type 304 stainless steel lasts in municipal sewage and is the rail most wet wells carry; Type 316 is specified where chlorides are present, from brackish infiltration, road salt in combined flow, or an industrial contributor, and where the wet well atmosphere is the hydrogen sulfide of a long force main. Galvanized steel is the lowest first cost and the one whose coating the wet well air consumes within a few years. The plant pump sees a more aggressive wet well than the lift station on a cul-de-sac, which is why no material is the norm here. {note}
+
+### Guide rails shall be of the schedule and the diameter the manufacturer publishes for the pump weight and the rail length, and no rail shall be smaller than 2 in. nominal pipe size.
+
+### Intermediate guide brackets shall be furnished at the spacing indicated in the datasheet, anchored to the wet well wall with Type 316 stainless steel anchors.
+
+```datasheet
+label: Intermediate Guide Bracket Spacing
+type: range
+unit: ft
+options:
+ min: 6
+ max: 20
+ setpoints: [6, 8, 10, 12, 15, 20]
+constraint: max
+```
+
+### The upper guide bracket shall be anchored to the hatch frame or to the wet well top so that the rails are held plumb and the pump bracket enters the rails with the pump hanging from its chain.
+
+### An unsupported rail flexes as the pump slides down it, and a flexed rail lets the pump bracket cock and the pump seat crooked on the elbow or jam a foot above it. The manufacturer publishes a bracket spacing for its rail size, and the datasheet sets the spacing where the project knows its wet well depth; where none is indicated, the manufacturer's published spacing governs. {note}
+
+## Lifting Chain {toc}
+
+### Each pump shall be furnished with the lifting means indicated in the datasheet, with a working load limit not less than the weight of the pump and motor assembly, long enough to reach from the pump seated on the elbow to the hatch frame with slack for the hook, and secured at the hatch frame with a stainless steel hook or bracket.
+
+```datasheet
+label: Lifting Means
+type: radio
+options:
+ - "Stainless steel chain with lifting rings"
+ - "Stainless steel wire rope"
+ - "Galvanized alloy steel chain"
+default: "Stainless steel chain with lifting rings"
+```
+
+### A lifting chain shall be fitted with a lifting ring or a link at intervals not exceeding 3 ft, so that a hoist with a lift shorter than the wet well depth can take the pump out in stages.
+
+### Stainless chain is the lifting means of the plant pump because it is pulled out of sewage a few times a year for decades, and the rings along it are what let a portable hoist with a short lift bring a deep pump out in stages. Wire rope coils onto a reel and takes less room at the hatch, and it kinks and corrodes at the swage where a chain does not; galvanized alloy chain has the highest strength for its size and loses its zinc to the wet well air. {note}
+
+### The manufacturer shall state the submerged and the dry weight of the pump and motor assembly on the submittal, and the lifting equipment shown on the drawings shall be rated for the dry weight.
+
+# Dry-Pit and Self-Priming Mounting {toc}
+
+## Dry-Pit Submersible Mounting {toc}
+
+### Requirements in this article apply where a dry-pit submersible arrangement is selected in the datasheet.
+
+### A vertical dry-pit submersible pump shall be mounted on a cast iron or fabricated steel stand with a flanged suction inlet at the base and the discharge flanged for connection to the discharge piping, anchored to the housekeeping pad.
+
+### A horizontal dry-pit submersible pump shall be mounted on a fabricated steel or cast iron support frame, with the pump and motor carried on the frame and the suction and discharge flanged, anchored to the housekeeping pad.
+
+### Suction and discharge flanges shall be of the class indicated in the datasheet.
+
+```datasheet
+label: Pump Connection Flange Class
+type: radio
+options:
+ - "ASME B16.1 Class 125 or ASME B16.42 Class 150, flat faced"
+ - "ASME B16.1 Class 250 or ASME B16.42 Class 300"
+ - "ASME B16.5 Class 150, stainless steel"
+default: "ASME B16.1 Class 125 or ASME B16.42 Class 150, flat faced"
+```
+
+### A flat-faced Class 125 or Class 150 flange matches the ductile iron piping of a wastewater plant and is the pump flange as sold; a Class 250 or 300 flange is bought where the shutoff head of a high-head pump exceeds the lower class's rating at the discharge, and a stainless B16.5 flange is the flange of a stainless pump in a corrosive service, mating to the stainless piping under [[sync/steel-and-stainless-process-piping]]. {note}
+
+### The dry pit shall be provided with the sump, sump pump, and ventilation shown on the drawings, and a dry-pit submersible pump shall be rated under the Motor Cooling article of this standard to run through a flood of the dry pit.
+
+### The suction isolation valve at the wet well wall, operable from the dry pit, is furnished under [[sync/resilient-seated-gate-valves]], [[sync/eccentric-plug-valves]], or [[sync/knife-gate-valves]], and the wall pipe through the wet well wall is furnished under [[sync/water-retaining-concrete-structures]]; this standard requires that each dry-pit pump be removable without draining the wet well.
+
+## Dry-Pit Conventional Motor Mounting and Coupling {toc}
+
+### Requirements in this article apply where a dry-pit arrangement with a conventional motor is selected in the datasheet.
+
+### The motor shall be mounted as indicated in the datasheet.
+
+```datasheet
+label: Dry-Pit Conventional Motor Mounting
+type: radio
+options:
+ - "Close-coupled, motor flange-mounted to the pump"
+ - "Frame-mounted, pump and motor on a common baseplate"
+ - "Elevated motor on a floor stand with an intermediate shaft"
+```
+
+### A close-coupled dry-pit pump removes the coupling and the alignment and takes the motor off to reach the seal; a frame-mounted horizontal pump on a baseplate reaches the seal and the bearings in place through a spacer coupling and takes the most floor area. An elevated motor on a floor stand, driving a vertical pump through an intermediate universal or flexible shaft, puts the motor above the flood level of the dry well and leaves the pump at the floor where the suction enters, and it is the arrangement of most large vertical dry-pit sewage pumps. {note}
+
+### Where a 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, and it shall include a spacer that permits removal of the seal without moving the motor.
+
+```datasheet
+label: Coupling Type
+type: select
+options:
+ - "Elastomeric element spacer coupling"
+ - "Metallic disc spacer coupling"
+ - "Grid spacer coupling"
+ - "Universal joint intermediate shaft"
+ - "Flexible intermediate shaft with couplings at each end"
+ - "Not applicable, close-coupled"
+```
+
+### An elastomeric element takes misalignment by deforming, absorbs the torque pulse of a rag passing through the impeller, and is the wear part the guard is opened to inspect; a metallic disc pack takes misalignment by flexing steel, has no wear part, and fails abruptly when its limit is passed; a grid coupling carries the highest torque for its size and is the coupling of the largest pumps. An intermediate shaft between an elevated motor and the pump is a universal joint shaft where the stand is tall and the offset small, and a flexible shaft with a coupling at each end where the manufacturer's design uses one. {note}
+
+### The baseplate, its leveling, its grouting, and the coupling guard are governed by [[sync/common-work-results-process]], and coupling alignment shall be recorded cold and after the pump has reached operating temperature in the startup report.
+
+### The volute of a dry-pit pump with a conventional motor shall be furnished with a hand-hole cleanout cover sized to clear the impeller passage, so that the impeller can be cleared of rags without removing the suction piping.
+
+## Self-Priming Pump Mounting {toc}
+
+### Requirements in this article apply where a self-priming arrangement is selected in the datasheet.
+
+### The pump shall reprime, without a foot valve and without manual priming, at the static suction lift indicated in the datasheet, with the suction line empty and the priming chamber holding only the liquid retained from the previous cycle.
+
+```datasheet
+label: Static Suction Lift at the Pump-Off Level
+type: range
+unit: ft
+drawing_ref: "the pump station plans and sections"
+options:
+ min: 5
+ max: 28
+ setpoints: [5, 10, 12, 15, 18, 20, 22, 25, 28]
+default: deferred
+constraint: min
+```
+
+### The priming chamber shall retain enough liquid to reprime at the lift stated, and the pump shall be furnished with a suction check valve in the priming chamber, a removable cover plate giving access to the impeller and the wear plate without disturbing the piping, and an external adjustment of the impeller clearance.
+
+### The suction piping from the wet well to each pump shall be airtight, shall rise continuously to the pump with no high point, and shall be of the diameter the pump manufacturer publishes for the repriming lift, with its own intake in the wet well and a vacuum gauge connection at the pump.
+
+### The pump shall be mounted on a baseplate, grouted under [[sync/common-work-results-process]], and the motor shall be governed by [[sync/electric-motors]].
+
+### A self-priming pump reprimes by evacuating the suction line through the volute, and the lift it can reprime against falls as the water warms, the altitude rises, and the wear plate clearance opens. The lift on the drawings is the static lift at the pump-off level, which is the worst case the pump sees, and the suction line is the part of the station that fails: an air leak at a flange the pump cannot evacuate, or a high point that traps a pocket, is a pump that runs and does not pump. {note}
+
+# Shop Coating {toc}
+
+## Exterior and Interior Coating System {toc}
+
+### Ferrous exterior surfaces of the pump, the motor housing, the discharge elbow, and the dry-pit stand, except machined faces, shall be blast cleaned to SSPC-SP 10/NACE No. 2 and coated at the factory with the system indicated in the datasheet.
+
+```datasheet
+label: Exterior Shop Coating System
+type: select
+options:
+ - "Two-part liquid epoxy"
+ - "Fusion-bonded epoxy"
+ - "Zinc-rich primer with an epoxy topcoat"
+default: manufacturer
+```
+
+### The shop coating shall be applied to a total dry film thickness not less than the value indicated in the datasheet, measured under SSPC-PA 2, and where no thickness is indicated the manufacturer's standard thickness shall be stated on the submittal.
+
+```datasheet
+label: Shop Coating Dry Film Thickness
+type: range
+unit: mils
+options:
+ min: 4
+ max: 20
+ setpoints: [4, 6, 8, 10, 12, 16, 20]
+constraint: min
+```
+
+### A two-part liquid epoxy is the coating every submersible pump manufacturer applies as standard, sprayed on the blast-cleaned casting and cured in the shop, and it is a complete barrier for a pump in sewage. Fusion-bonded epoxy is a powder applied to a heated casting and is the harder and more uniform film, offered by the manufacturers whose castings fit their ovens; a zinc-rich primer under epoxy adds galvanic protection for a pump that will stand in a damp dry well for decades. The manufacturer's standard is accepted because each manufacturer's system is proven on its own castings, and the thickness is set where the project has a reason, such as a grit-laden service that abrades the volute interior. {note}
+
+### The wetted interior surfaces of the volute and the impeller shall be coated as indicated in the datasheet.
+
+```datasheet
+label: Wetted Interior Coating
+type: radio
+options:
+ - "Coated with the same system as the exterior"
+ - "Uncoated iron"
+default: manufacturer
+```
+
+### Stainless steel surfaces shall not be coated.
+
+### Coating damaged in shipment or installation shall be repaired with the coating manufacturer's repair material in accordance with the coating manufacturer's written procedure, and repair that cannot restore a continuous film shall be cause for rejection of the pump.
+
+### The exterior finish of a dry-pit or self-priming pump shall be as indicated in the datasheet.
+
+```datasheet
+label: Exterior Finish of Exposed Pumps
+type: radio
+options:
+ - "The shop coating is the finished exterior"
+ - "Field-applied finish coat over the shop coating under high-performance-coatings"
+```
+
+### Where a field-applied finish coat is selected, the shop coating shall be compatible with the finish coat system furnished under [[sync/high-performance-coatings]], and the pump manufacturer shall state the surface preparation the finish coat requires over its shop coating.
+
+### A submersible pump is never seen, and its shop epoxy is its finish for life. A dry-pit pump in a gallery whose piping is color-coded is topcoated in the field to the plant's scheme, and the shop epoxy becomes the primer that topcoat has to bond to; the decision follows the plant's finish scheme rather than the pump. {note}
+
+# Factory Testing {toc}
+
+## Tests Required {toc}
+
+### Each pump shall receive the factory tests indicated in the datasheet before shipment, in addition to the manufacturer's standard production tests, and the certified reports shall be submitted under [[sync/common-work-results-process]].
+
+```datasheet
+label: Factory Tests Required
+type: checkbox
+options:
+ - "Hydraulic performance test at the rated speed"
+ - "NPSH test at the rated condition"
+ - "Hydrostatic test of the volute and seal chamber"
+ - "Motor insulation resistance test"
+ - "Seal chamber and motor housing pressure test"
+ - "Sensor continuity and function test"
+ - "Vibration measurement under ANSI/HI 9.6.4 factory values"
+ - "Sound pressure level measurement"
+default:
+ - "Hydraulic performance test at the rated speed"
+ - "Hydrostatic test of the volute and seal chamber"
+ - "Motor insulation resistance test"
+ - "Seal chamber and motor housing pressure test"
+ - "Sensor continuity and function test"
+constraint: all_of
+```
+
+### The hydraulic performance test shall be conducted under the standard indicated in the datasheet.
+
+```datasheet
+label: Factory Performance Test Standard
+type: radio
+options:
+ - "ANSI/HI 11.6, pump tested as a unit with its submersible or immersible motor"
+ - "ANSI/HI 14.6, pump tested with a calibrated shop motor or with the job motor"
+derived: "the pump arrangement selected in this standard"
+default: derived
+```
+
+### A pump with a submersible or immersible motor shall be tested with the motor furnished, and the test shall report wire-to-water efficiency and input power at each point.
+
+### The performance test shall record not fewer than five points, including shutoff, the rated condition, the runout condition, and a point on each side of the rated condition, and for a variable-speed pump the rated condition at the minimum continuous speed as well.
+
+### ANSI/HI 11.6 was written for the submersible pump because the pump and motor are one machine and cannot be tested apart: it tests the hydraulic performance, the hydrostatic integrity, the motor and the seals, and the sensors, as one acceptance, and reports a wire-to-water efficiency that the motor is inside. ANSI/HI 14.6 tests the pump end alone, with a shop motor and a torque measurement, and is the test for a pump whose motor is bought under [[sync/electric-motors]]; the standard follows the arrangement, which is why the field derives. {note}
+
+## Acceptance Grade {toc}
+
+### The hydraulic performance test shall be judged to the acceptance grade indicated in the datasheet.
+
+```datasheet
+label: Hydraulic Performance Acceptance Grade
+type: select
+options:
+ - "Grade 1B"
+ - "Grade 1E"
+ - "Grade 1U"
+ - "Grade 2B"
+ - "Grade 2U"
+ - "Grade 3B"
+```
+
+### Where the datasheet indicates no acceptance grade, the pump manufacturer shall state on the submitted curve the acceptance grade on which its published tolerances are based, and the test shall be judged to that grade.
+
+### Where a tested pump falls outside the tolerance band of the grade applied, the manufacturer shall correct or replace the pump and retest it at the manufacturer's cost, and a correction by impeller change shall be followed by a retest of the pump as corrected.
+
+### The grade number sets how wide the tolerance band is and the letter sets how it is placed: Grade 1 is the tightest and Grade 3 the widest, a B suffix places the band around the guarantee, a U suffix removes the negative half so the pump can exceed the guarantee and never fall short, and the E suffix is the bilateral grade for a pump whose efficiency is the guaranteed quantity. Most solids-handling pumps are tested to Grade 2B, which is the grade the manufacturers' published curves are drawn to; Grade 1 is bought on the large pump whose head-capacity envelope is tight, and a unilateral grade moves the selection risk onto the manufacturer and is priced that way. {note}
+
+## Witnessed Tests {toc}
+
+### The factory performance test of each pump with a motor at or above the horsepower indicated in the datasheet is designated a witnessed test for the purposes of [[sync/common-work-results-process]], and where the datasheet indicates no horsepower, no pump test under this standard is designated.
+
+```datasheet
+label: Motor Horsepower Threshold for a Witnessed Factory Test
+type: range
+unit: hp
+options:
+ min: 0
+ max: 500
+ setpoints: [0, 25, 50, 75, 100, 150, 200, 300, 500]
+constraint: exact
+```
+
+### A threshold of 0 hp designates every pump on the project. The witnessed test is bought where a performance shortfall would be corrected on the test stand in an afternoon and in the plant in a season, which is the large influent pump and the pump whose duty sits at the edge of its curve; a threshold at 100 hp or so is where many plants draw it, and a plant of small duplicated pumps draws none. {note}
+
+# Field Testing {toc}
+
+## Drawdown and Performance Test {toc}
+
+### After startup under [[sync/common-work-results-process]], each pump shall receive the field tests indicated in the datasheet, and the results shall be the field performance test of the pump under that standard.
+
+```datasheet
+label: Field Tests Required
+type: checkbox
+options:
+ - "Drawdown test of each pump alone"
+ - "Drawdown test of each combination of pumps that can run together"
+ - "Flow by the plant flow meter against the certified curve"
+ - "Motor voltage and current at the rated condition"
+ - "Discharge pressure at the rated condition"
+ - "Seal leak and thermal sensor function by simulation at the panel"
+ - "Seating of each pump on its discharge elbow"
+ - "Variable-speed operation at the minimum, an intermediate, and the rated speed"
+default:
+ - "Drawdown test of each pump alone"
+ - "Drawdown test of each combination of pumps that can run together"
+ - "Motor voltage and current at the rated condition"
+ - "Discharge pressure at the rated condition"
+ - "Seal leak and thermal sensor function by simulation at the panel"
+ - "Seating of each pump on its discharge elbow"
+constraint: all_of
+```
+
+### The drawdown test shall time the drawdown of the wet well between two measured levels with the influent blocked or measured, and the pumping rate so determined, corrected for the influent during the test, shall be plotted on the certified curve at the measured discharge head.
+
+### The measured pumping rate shall fall within the tolerance of the factory acceptance grade applied, widened by the uncertainty of the wet well volume and the influent measurement the Contractor states in the test report, and a pump that falls outside it shall be corrected and retested at the Contractor's cost.
+
+### Where the plant has a flow meter on the pump discharge under [[sync/flow-measurement]], the meter reading shall be recorded with the drawdown rate, and a difference between the two greater than the meter's stated accuracy shall be reported to the Engineer of Record.
+
+### The drawdown test is the field measurement of what the pump actually pumps: a pump that passed its factory test can deliver less in the ground because of an elbow that did not seat, a check valve that did not open fully, a wear ring that opened on the first month of grit, or a force main longer than the calculation assumed, and the drawdown is the one test that sees all of them. {note}
+
+## Vibration and Sound of Submerged Pumps {toc}
+
+### The vibration acceptance under [[sync/common-work-results-process]] applies to a dry-pit or self-priming pump at its bearing housings; for a submersible pump in a wet well, the factory vibration measurement under ANSI/HI 11.6 is the vibration acceptance, and the field test shall record the motor current, the discharge pressure, and the sound at the hatch in place of a bearing housing reading.
+
+### A pump that cavitates, that seats crooked on its elbow, or that carries a rag on one vane announces itself in a wet well by a current that swings, a pressure that pulses, and a sound an operator at the hatch hears, long before anything could be measured on a motor housing six feet under sewage. {note}
+
+# Installation {toc}
+
+## Setting the Elbow, Rails, and Pump {toc}
+
+### The discharge elbow shall be set level on the wet well floor at the location shown on [[drawing: the pump station plans and sections]], anchored under [[sync/common-work-results-process]], and the anchors shall not be torqued until the grout under the base, where the manufacturer requires grout, has reached its working strength.
+
+### The guide rails shall be set plumb from the elbow to the upper guide bracket, and the intermediate brackets shall be anchored at the spacing under the Guide Rails and Brackets article of this standard before the pump is lowered.
+
+### Before the wet well is placed in service, each pump shall be lowered on its rails, seated on its elbow, and lifted again, and a pump that does not seat by its own weight shall not be accepted until the cause is corrected.
+
+### The lifting chain shall be hung from its hook at the hatch frame with no slack lying on the pump, and the cable shall be gripped at the hatch frame and supported so that no load reaches the cable entry.
+
+### The wet well floor shall be cleaned of construction debris, and the wet well shall be flushed before the first start, so that the first thing the pump passes is not a brick.
+
+### A pump that seats on the second try is a pump that will not seat on the fifth, when the rails have grown a coat of grease and the operator is alone at the hatch at night; the seating test with the well dry is where a rail that is a quarter inch out of plumb is found and fixed for nothing. {note}
+
+## Cable Routing and Classified-Location Entries {toc}
+
+### The pump cable shall be routed from the wet well to the junction box outside the classified location through the raceway shown on the drawings, without a splice in the wet well, and the junction box shall be mounted where the cable can be disconnected and withdrawn with the pump.
+
+### The conduit seal at the boundary where the pump cable raceway leaves the classified location, and the installation of the raceway within the classified location, are governed by NFPA 70 Articles 500 through 504 and are not yet owned by a SynC standard; this standard requires that the cable be of the length under the Power and Sensor Cable article to reach the junction box without a splice.
+
+### The junction box outside the wet well is where a pump is disconnected before it is lifted, and where the spare pump is connected after it; a box that is reached only from inside the wet well, or a cable terminated in the panel across the yard, turns a pump change into a confined space entry or a cable pull. {note}
+
+## Dry-Pit and Self-Priming Setting {toc}
+
+### Dry-pit and self-priming pumps shall be set on housekeeping pads under [[sync/concrete-pads]], on their stands or baseplates leveled and grouted under [[sync/common-work-results-process]], at the locations shown on [[drawing: the pump station plans and sections]].
+
+### The suction and discharge piping shall be connected without strain on the pump flanges, and the piping shall be supported under the governing process piping standard so that no piping weight or thrust is carried by the pump.
+
+### Suction reducers on a horizontal dry-pit pump shall be eccentric and installed flat side up, and the suction piping shall have no high point between the wet well and the pump.
+
+### Clearance shall be maintained at each dry-pit pump for removal of the motor, the rotating element, and the seal, and for access to the cleanout cover, as shown on the drawings.
+
+### A concentric reducer on a horizontal suction 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, and installed flat side down makes a worse one. {note}
+
+# Delivery, Storage, and Handling {toc}
+
+## Delivery and storage of pumps are governed by [[sync/common-work-results-process]], and the provisions below are particular to the submersible pump.
+
+## Submersible pumps shall be stored upright on their shipping pallets under cover, with the cable coiled and the cable ends sealed against moisture until termination, and the cable shall not be used to lift, drag, or steady the pump at any time.
+
+## The seal chamber oil level shall be checked before the pump is lowered into the wet well, and a pump whose seal chamber shows water or a low oil level shall be reported to the manufacturer before installation.
+
+## A pump stored longer than the manufacturer's storage limit shall have its impeller rotated by hand and its seal chamber inspected under the manufacturer's long-term storage procedure before installation.
+
+## A cable end left open on a pallet in the rain wicks water down the conductors into the motor before the pump is ever wet, and the first insulation resistance reading at startup is where it is found; a sealed cable end costs a cap. {note}
+
+# Warranty {toc}
+
+## Pump Warranty Term {toc}
+
+### The pump and its motor shall be warranted against defects in materials and workmanship for the period indicated in the datasheet, measured from the date of substantial completion, which applies in place of the term under [[sync/common-work-results-process]] where it is longer.
+
+```datasheet
+label: Pump and Motor Warranty Period
+type: range
+unit: years
+options:
+ min: 1
+ max: 5
+ setpoints: [1, 2, 3, 5]
+default: 1
+constraint: min
+```
+
+### The warranty coverage shall be on the basis indicated in the datasheet.
+
+```datasheet
+label: Warranty Coverage Basis
+type: radio
+options:
+ - "Full coverage of parts and labor for the whole term"
+ - "Full coverage for the first year and prorated parts coverage for the remainder of the term"
+default: "Full coverage of parts and labor for the whole term"
+```
+
+### Warranty repair of a submersible pump shall include removal of the pump from the wet well, transport to and from the service facility, and reinstallation, at no cost to the Owner.
+
+### The re-warranty of a repaired or replaced component, collateral damage, and the warranty administration are governed by [[sync/common-work-results-process]].
+
+### One year from substantial completion is the term most projects carry and the one every manufacturer gives; the submersible pump manufacturers also sell multi-year prorated programs on the pump and motor, which cover the parts at a declining share and the labor not at all after the first year, and a plant that has seen a stator fail in year three buys one. A full multi-year warranty is priced by the Contractor as a risk and is bought by the utility that will not have the staff to argue a claim. {note}
+
+## Warranty Exclusions {toc}
+
+### Warranty coverage shall not extend to damage caused by operation outside the allowable operating region, by running the motor exposed where it is rated only for submerged operation, by a pump-off level set below the level the manufacturer stated on the submittal, or by operation with the seal leak alarm active beyond the period the manufacturer's manual permits, provided the manufacturer stated each limit on the submittal.
+
+### Warranty coverage shall not extend to wear of cutting elements, wear rings, and wear plates beyond the manufacturer's published wear life in the service stated on the datasheet, provided the manufacturer stated that wear life on the submittal.
+
+### An exclusion is enforceable only where the limit it relies on was published where the Owner could see it, which is why each exclusion is conditioned on the limit appearing in the submittal rather than surfacing after a failure. {note}
+
+# Spare Parts {toc}
+
+## Spare Parts Furnished with the Pumps {toc}
+
+### The spare parts indicated in the datasheet shall be furnished for the pumps under this standard, on the basis selected under [[sync/common-work-results-process]], and delivered before substantial completion.
+
+```datasheet
+label: Spare Parts Furnished
+type: checkbox
+options:
+ - "One set of mechanical seals for each pump model"
+ - "One set of O-rings and gaskets for each pump model"
+ - "Seal chamber oil for one fill of each pump"
+ - "One set of wear rings or one wear plate for each pump model"
+ - "One cutter bar and one set of cutting elements for each chopper pump model"
+ - "One impeller for each pump model"
+ - "One set of bearings for each pump model"
+ - "One set of seal leak and thermal monitoring relays"
+ - "One complete pump and motor assembly of the most numerous size"
+default:
+ - "One set of mechanical seals for each pump model"
+ - "One set of O-rings and gaskets for each pump model"
+ - "Seal chamber oil for one fill of each pump"
+ - "One set of wear rings or one wear plate for each pump model"
+constraint: all_of
+```
+
+### Spare parts shall be interchangeable with the parts installed, packaged for long-term storage, and labeled with the equipment numbers they serve and the manufacturer's part numbers.
+
+### The seal is the part that fails first on a submersible pump and the wear ring is the part that wears first, and both are changed at the service facility with the pump on a bench; the parts on the shelf are what turn that into a two-day job. A complete spare pump is bought by the plant with a single influent station and no bypass, where a pump out for a rewind is a station at firm capacity for the month the rewind takes. {note}
+
+## Special Tools {toc}
+
+### The Contractor shall furnish the manufacturer's special tools for the pumps, including the impeller puller, the seal setting fixture, the clearance adjustment gauge where the impeller clearance is adjustable, and the seal chamber fill and drain tools, labeled with the pump models they serve.
+
+### The certified curve for each pump, marked with the field drawdown point, shall be placed in the operation and maintenance manual under [[sync/common-work-results-process]].