100HP_Headworks_pumps_spec.pdf

SUBMERSIBLE PUMP SPECIFICATION

PART 1: GENERAL

1.01 SCOPE OF WORK

A. Furnish and install submersible non-clog wastewater pump(s). Each pump shall be equipped with a close coupled 100 HP, submersible electric motor connected for operation on 480 volts, 3 phase, 60 hertz, and submersible cable (SUBCAB) suitable for submersible pump applications.

B. The power cable shall be sized according to NEC and ICEA standards and per the electrical plans and specifications.

1.02 SCOPE OF WORK

A. Pump(s) shall be installed in those locations shown on the Drawings.

B. Pump(s) shall be FLYGT MODEL NP-3306.665 or approved equal.

1.03 QUALIFICATIONS

A. All of the pump(s) shall be furnished by manufacturers who are fully experienced, reputable, and qualified in the manufacture of the equipment/materials to be furnished. The pump(s) shall be designed, constructed, installed in accordance with the best practices and methods and shall comply with these Specifications as applicable.

1.04 SUBMITTALS

A. Submit to the Owner (City) within thirty (30) days after execution of the Contract a list of materials/equipment to be furnished, the names of the suppliers and the date of delivery of materials to the site.

B. All pump(s) to be installed under this Contract shall be inspected and tested at the foundry as required by the standard specifications to which the equipment/material is manufactured. Furnish in duplicate to the Engineer sworn certificates of such tests and their results. In addition, all pump(s) to be installed under this Contract may be inspected at the foundry for compliance with these Specifications by an independent testing laboratory selected by the Owner. The manufacturer's cooperation shall be required in these inspections.

C. Shop Drawings shall be submitted to the Owner (City) for approval in accordance with General Conditions and shall include dimensioning, methods and locations of supports and all other pertinent technical specifications for all pump(s) to be furnished. Shop drawings shall be prepared by the pump(s) manufacturer.

PART 2: PRODUCTS

2.01 PUMP DESIGN CONFIGURATION (Wet pit installation)

A. The pump shall be supplied with a mating cast iron 12 inch discharge connection and be capable of delivering 3800 GPM at 63 FT. TDH. An additional point on the same curve shall be 4500 GPM at 57 feet total head. Shut off head shall be 94 feet (minimum). The pump(s) shall be automatically and firmly connected to the discharge connection, guided by no less than two guide bars extending from the top of the station to the discharge connection. There shall be no need for personnel to enter the wet-well. Sealing of the pumping unit to the discharge connection shall be accomplished by a machined metal to metal watertight contact. Sealing of the discharge interface with a diaphragm, O-ring or profile gasket will not be acceptable. The entire weight of the pump/motor unit shall be borne by the pump discharge elbow. No portion of the pump shall bear directly on the sump floor. Each pump shall be fitted with nylon lifting chain or stainless-steel cable. The working load of the lifting system shall be 50% greater than the pump unit weight.

B. Power and pilot cable supports shall be provided and consist of a wire braid sleeve with attachment loops or tails to connection to the under side of the access frame.

C. Pump(s) should be able to be installed and removed with the owner’s existing Bay Area overhead bridge crane with no need for exterior equipment.

D. No modifications shall be made to the existing wet pit.

2.02 PUMP CONSTRUCTION

A. Major pump components shall be of grey cast iron, ASTM A-48, Class

35B, with smooth surfaces devoid of blow holes or other casting irregularities. All exposed nuts or bolts shall be AISI type 316 stainless steel. All metal surfaces coming into contact with the pumped media, other than stainless steel, shall be protected by a factory applied spray coating of acrylic dispersion zinc phosphate primer with a polyester resin paint finish on the exterior of the pump.

B. Sealing design shall incorporate metal-to-metal contact between machined surfaces. Pump/Motor unit mating surfaces where watertight sealing is required shall be machined and fitted with Nitrile or optional Viton rubber O-rings. Joint sealing will be the result of controlled compression of rubber O-rings in two planes and O-ring contact of four sides without the requirement of a specific bolt torque limit. Rectangular cross sectioned rubber, paper or synthetic gaskets that require specific torque limits to achieve compression shall not be considered as adequate or equal. No secondary sealing compounds, elliptical O-rings, grease or other devices shall be used.

2.03 COOLING SYSTEM

A. Each pump/motor unit shall be equipped with an integral, closed-loop motor cooling system. The motor cooling jacket shall encircle the stator housing and shall be of Type 304 stainless steel. The closed-loop motor cooling system shall provide heat dissipation for the motor regardless of whether the motor unit is submerged in the pumped media or surrounded by air in dry-pit installation mode. A high efficiency impeller, integral to the cooling system and driven by the pump shaft, shall provide the necessary circulation of the cooling liquid through the system. The cooling liquid shall pass about the stator housing in the closed loop system between the motor housing and close-fitting guide sleeve in turbulent flow providing for superior heat transfer. The cooling system shall have one fill port and one drain port integral to the cooling jacket. The cooling system shall provide for continuous pump operation in liquid or ambient temperatures of up to 104°F (40°C) in accordance with NEMA standards. Operational restrictions that limit the ambient or pumped liquid temperatures at levels less than 40°C are not acceptable.

2.04 CABLE ENTRY SEAL

A. The cable entry seal design shall preclude specific torque requirements to insure a watertight and submersible seal. The cable entry shall consist of dual cylindrical elastomer grommets, flanked by washers, all having a close tolerance fit against the cable outside diameter and the cable entry inside diameter. The grommets shall be compressed by the cable entry unit, thus providing a strain relief function. The assembly shall provide ease of changing the cable when necessary using the same entry seal.

The cable entry junction chamber and motor shall be sealed from each other, which shall isolate the stator housing from foreign material gaining access through the pump top. Epoxies, silicones, or other secondary sealing systems shall not be considered acceptable.

2.05 MOTOR

A. The pump motor shall be a NEMA B design, induction type with a squirrel cage rotor, shell type design, housed in an air filled, watertight chamber.

The stator windings shall be insulated with moisture resistant Class H insulation rated for 180°C (356°F). The stator shall be insulated by the current-UV-dip impregnation method using Class H monomer-free polyester resin resulting in a winding fill factor of at least 95%. The motor shall be inverter duty rated in accordance with NEMA MG1, Part 31. The stator shall be heat-shrink fitted into the cast iron stator housing. The use of multiple step dip and bake-type stator insulation process is not acceptable. The use of bolts, pins or other fastening devices requiring penetration of the stator housing is not acceptable. The motor shall be specifically designed for submersible pump usage and designed for continuous duty pumping media of up to 40°C (104°F) with an 80°C temperature rise and capable of at least 15 evenly spaced starts per hour.

The rotor bars and short circuit rings shall be made of cast aluminum.

Thermal switches shall be embedded in the stator end coils to monitor the temperature of each phase winding. One PT-100 type temperature sensor shall be installed in the stator winding. These thermal switches shall be used in conjunction with and supplemental to external motor overload protection and shall be connected to the control panel. The junction chamber shall be sealed off from the stator housing and shall contain a terminal board for connection of power and pilot sensor cables using threaded compression type terminals. A mechanical float switch (FLS) shall be mounted in the junction chamber to signal if there is water intrusion. A pump memory module shall be provided and mounted in the junction chamber to record pump run time, number of starts as well as contain the motor unit performance and manufacturing data and service history. The use of wire nuts or crimp-type connectors is not acceptable.

The motor and the pump shall be produced by the same manufacturer.

B. The combined service factor (combined effect of voltage, frequency and specific gravity) shall be a minimum of 1.15. The motor shall have a voltage tolerance of plus or minus 10%. The motor shall be designed for operation up to 40°C (104°F) ambient and with a temperature rise not to exceed 80°C. A performance chart shall be provided upon request showing curves for torque, current, power factor, input/output kW and efficiency. This chart shall also include data on starting and no-load characteristics.

C. The power cable shall be sized according to the NEC and ICEA standards and shall be of sufficient length to reach the junction box without the need of any splices. The outer jacket of the cable shall be oil resistant chlorinated polyethylene rubber. The motor and cable shall be capable of continuous submergence underwater without loss of watertight integrity to a depth of 65 feet or greater. Provide kellems grip for the cable at no additional cost to the owner.

D. The motor horsepower shall be adequate so that the pump is non-overloading throughout the entire pump performance curve from shut-off through run-out.

2.06 PILOT CABLE

A. The pilot cable shall be designed specifically for use with submersible pumps and shall be type SUBCAB (Submersible Cable). The cable shall be multi-conductor type with stainless steel braided shielding, a chlorinated polyethylene rubber outer jacket and tinned copper conductors insulated with ethylene-propylene rubber. The conductors shall be arranged in twisted pairs. The cable shall be rated for 600 Volts and 90°C (194°F) with a 40°C (104°F) ambient temperature and shall be approved by Factory Mutual (FM). The cable length shall be adequate to reach the junction box without the need for splices. Provide kellems grips for the cable at no additional cost to the owner.

2.07 BEARINGS

A. The pump shaft shall rotate on at least three grease-lubricated bearings.

The lower bearings shall consist of at least one roller bearing for radial forces and one or two angular contact ball bearings for axial thrust.

B. The minimum L10 bearing life shall be 100,000 hours at any point along the usable portion of the pump curve at maximum product speed.

C. The lower bearing housing shall include an independent thermal sensor to monitor the bearing temperature. If a high temperature occurs, the sensor shall activate an alarm and shut the pump down.

2.08 MECHANICAL SEAL

A. Each pump shall be provided with a tandem mechanical shaft seal system consisting of two totally independent seal assemblies. The lower seal shall be independent of the impeller hub. The seals shall operate in a lubricant reservoir that hydro-dynamically lubricates the lapped seal faces at a constant rate. The lower, primary seal unit, located between the pump and the lubricant chamber, shall contain one stationary and one positively driven rotating corrosion resistant tungsten-carbide seal ring. The upper, secondary seal unit, located between the lubricant chamber and the motor housing, shall be a leakage-free seal. The upper seal shall contain one stationary and one positively driven rotating corrosion resistant tungsten-carbide seal ring. The rotating seal ring shall have small back-swept grooves laser inscribed upon its face to act as a pump as it rotates, returning any fluid that should enter the dry motor chamber back into the lubricant chamber. Each seal interface shall be held in contact by its own spring system. The seals shall require neither maintenance nor adjustment and shall be capable of operating in either clockwise or counter clockwise direction of rotation without damage or loss of seal. For special applications, other seal face materials shall be available.

B. Should both seals fail and allow fluid to enter the stator housing, a port shall be provided to direct that fluid immediately to the stator float switch to shut down the pump and activate an alarm. Any intrusion of fluid shall not come into contact with the lower bearings.

C. The following seal types shall not be considered acceptable or equal to the dual independent seal specified: shaft seals without positively driven rotating members, or conventional double mechanical seals containing either a common single or double spring acting between the upper and lower seal faces. No system requiring a pressure differential to offset pressure and to affect sealing shall be used.

D. Each pump shall be provided with a lubricant chamber for the shaft sealing system. The lubricant chamber shall be designed to prevent overfilling and to provide lubricant expansion capacity. The drain and inspection plug, with positive anti-leak seal shall be easily accessible from the outside. The seal system shall not rely upon the pumped media for lubrication. The motor shall be able to operate continuously while non-submerged without damage while pumping under load.

E. Seal lubricant shall be non-hazardous.

F. Pump lubricant (as per manufacturer’s specifications) shall be provided by the Vendor add no additional cost to the Owner.

2.09 PUMP SHAFT

A. Pump and motor shaft shall be a solid continuous shaft. The pump shaft is an extension of the motor shaft. Couplings shall not be acceptable. The pump shaft shall be of AISI 431 stainless steel.

2.10 IMPELLER

A. The impeller shall be of Hard-Iron (ASTM A-532 (Alloy III A) 25% chrome cast iron), dynamically balanced, semi-open, multi-vane, back swept, screw-shaped, non-clog design. The impeller leading edges shall be mechanically self-cleaned automatically upon each rotation as they pass across a spiral groove located on the volute suction. The leading edges of the impeller shall be hardened to Rc 60 and shall be capable of handling solids, fibrous materials, heavy sludge and other matter normally found in wastewater. The screw shape of the impeller inlet shall provide an inducing effect for the handling of up to 5% sludge and rag-laden wastewater. The impeller to volute clearance shall be readily adjustable by the means of a single trim screw. The impeller shall be locked to the shaft, held by an impeller bolt and shall be coated with alkyd resin primer.

2.11 VOLUTE / SUCTION COVER

A. The pump volute shall be a single piece grey cast iron, ASTM A-48, Class 35B, non-concentric design with smooth passages of sufficient size to pass any solids that may enter the impeller. Minimum inlet and discharge size shall be as specified. The volute shall have a replaceable suction cover insert ring in which are cast spiral-shaped, sharp-edged groove(s). The spiral groove(s) shall provide trash release pathways and sharp edge(s) across which each impeller vane leading edge shall cross during rotation so to remain unobstructed. The insert ring shall be cast of Hard-Iron (ASTM A- 532 (Alloy III A) 25% chrome cast iron) and provide effective sealing between the multi-vane semi-open impeller and the volute housing.

2.12 PROTECTION

A. The stator shall incorporate three thermal switches, connected in series, to provide over temperature protection of the motor winding. Should high temperature occur, the thermal switches shall open, stop the motor and activate an alarm. The stator shall also include one PT-100 type temperature probe to provide for monitoring of the stator temperature

B. A lower bearing temperature sensor shall be provided. The sensor shall directly contact the outer race of the thrust bearing providing for accurate temperature monitoring.

C. Two leakage sensors shall be provided to detect water intrusion into the stator chamber and junction chamber. A Float Leakage Sensor (FLS), a small float switch, shall be used to detect the presence of water in either the stator chamber or junction chamber. When activated, the FLS will stop the motor and activate an alarm. USE OF VOLTAGE SENSITIVE SOLID-

STATE SENSORS SHALL NOT BE ALLOWED.

D. The solid-state pump memory unit, three thermal switches, two FLS switches, PT-100 stator temperature monitor and the lower bearing PT- 100 temperature monitor shall all be connected to the existing Flygt MiniCAS.

PART 3: EXECUTION

3.01 HANDLING PUMPS

A. Care shall be taken in loading, transporting, and unloading to prevent damage to the pump(s). Pump(s) shall not be dropped. All pump(s) shall be examined before laying, and no pump(s) shall be installed which is found to be defective. Damaged pumps must be replaced at the Contractor’s expense.

B. All pump(s) shall be subjected to a careful inspection before being installed.

C. If any defective pump(s) is discovered after it has been laid, it shall be removed and replaced with a sound pump(s) in a satisfactory manner at no additional expense to the Owner.

3.02 TESTING

A. Testing of pump(s) shall be done in accordance to the manufacturer’s testing requirements.

3.05 WARRANTY

A. The pump(s) shall be warranted for a period of five years (60 months) by the manufacturer. Warranty shall start from the time of acceptance of project.

PART 4: VENDOR’S RESPONSIBILITY

4.00 Vendor’s Means and Methods of Construction

A. Vendor shall be solely responsible for the means, methods, techniques, sequences, and procedures of construction.

B. If the Contract Documents note, or Vendor determines, that professional engineering or other design services are needed to carry out Vendor’s responsibilities for construction means, methods, techniques, sequences, and procedures, or for Site safety, then Vendor shall cause such services to be provided by a properly licensed design professional, at Vendor’s expense. Such services are not Owner-delegated professional design services under this Contract, and neither Owner nor City Engineer has any responsibility with respect to (1) Contractor’s determination of the need for such services, (2) the qualifications or licensing of the design professionals retained or employed by Vendor, (3) the performance of such services, or (4) any errors, omissions, or defects in such services.

4.01 Services, Materials, and Equipment

A. Unless otherwise specified in the Contract Documents, Vendor shall provide and assume full responsibility for all services, materials, equipment, labor, transportation, construction equipment and machinery, tools, appliances, fuel, power, light, heat, telephone, water, sanitary facilities, temporary facilities, and all other facilities and incidentals necessary for the performance, testing, start up, and completion of the Work, whether or not such items are specifically called for in the Contract Documents.

B. All materials and equipment incorporated into the Work must be new and of good quality, except as otherwise provided in the Contract Documents.

All special warranties and guarantees required by the Specifications will expressly run to the benefit of Owner. If required by Owner (City), Vendor shall furnish satisfactory evidence (including reports of required tests) as to the source, kind, and quality of materials and equipment.

C. All materials and equipment must be stored, applied, installed, connected, erected, protected, used, cleaned, and conditioned in accordance with instructions of the applicable Supplier, except as otherwise may be provided in the Contract Documents.

4.02 “Or Equals and Product Substitution”

A. Vendor’s Request; Governing Criteria: Whenever an item of equipment or material is specified or described in the Contract Documents by using the names of one or more proprietary items or specific Suppliers, the Contract Price has been based upon Vendor furnishing such item as specified. The specification or description of such an item is intended to establish the type, function, appearance, and quality required. Unless the specification or description contains or is followed by words reading that no like, equivalent, or “or equal” item is permitted, Vendor may request that the Owner (City) authorize the use of other items of equipment or material, or items from other proposed Suppliers through the process shown on the Approved Equal & Product Substitution Procedures Form.