(A) Acceptable manufacturers. Pumps shall be manufactured by Flygt Corporation of Norwalk, Connecticut; Hydromatic Pumps, Inc. of Ashland, Ohio; Barnes Pumps, Inc. of Piqua, Ohio, or equal.
(B) Materials for submersible non clog pumps.
(1) Each pump shall be of the sealed submersible non-clog type capable of handling raw sanitary sewage. Pump casings, volute discharge pipe and flange, and sliding bracket shall be of gray iron. The impeller shall be gray iron of the non-clog design.
(2) Shaft seals shall be of suitable material capable of operating to a submerged pressure of 20 psi. The seal system shall not rely upon the pumped media for lubrication but instead shall have its own lubrication liquid chamber. No seal damage shall result from operating the pump out of its liquid environment. The seal system shall include a seal probe to detect the presence of water leakage. The probe signal shall be transmitted via the control cable to the alarm circuitry in the control panel.
(3) The motor casing shall be watertight, filled with air, or dielectric oil. All motors shall be supplied with heat sensing elements attached to the windings. The element shall trip the motor starter upon overheating. The element temperature setting shall be low enough to prevent damage to the pump but high enough to prevent unnecessary tripping. The sensor shall automatically reset when the motor cools to a safe temperature. The pump power cable shall enter the motor through a cord cap assembly, double sealed to protect the motor from moisture.
(4) A pump mounting base shall be provided and installed for each unit. The base shall include guide rails with supports as required, a base elbow and quick disconnect flanges for easy removal and proper pump alignment. Guide rails shall be made of stainless steal, sized to meet the pump loads. Each pump unit shall be supplied with a stainless steal lifting chain with hook which shall be fastened to the access hatch assembly.
(C) Lift station control panel.
(1) General.
(a) The pump manufacturer shall furnish an automatic pump station controller for operation on a 120/240-volt single phase or a 460-volt, three phase-three wires, and 60-hertz power source.
(b) The pump station controller shall be suitable for operation and automatic alternation of a duplex pump system and shall be complete with motor control, solid stale alternator, convenience power supply, miscellaneous controls, and the like. All components shall be UL listed.
(c) Controls for each two pumps shall be rated for the actual horsepower from the manufacturer’s information.
(d) The control power wirings for the pumps and level sensors shall be arranged to extend through two separate conduits to the wet well. Conduits shall be properly sealed to protect the panel from explosive type gasses, which may exist in the wet well.
(2) Panel enclosure.
(a) The enclosure shall be NEMA 4X with drip shield, 14-gauge stainless steel (minimum), welded construction. The enclosure shall have an outer weather door, a hinged “operator’s door” and mounting hardware.
(b) All equipment controls, and the like, shall be located inside the enclosure. Selector switches, pilot lights, and the like shall be located on the deadfront swingout panel (operator’s door) located behind an outside weather door. All other equipment, exposed wiring, and the like shall be located behind the swingout panel.
(3) Control features.
(a) Operating sequence.
1. When the pump is called for by the water level in the wet well, the control unit shall send a start signal to the appropriate pump and verify operation with the starter auxiliary contact. Appropriate verification time delays shall be included.
2. When the wet well level continues to raise, the second pump shall start.
3. When the wet well level reaches low level, the pump(s) shall stop and pump alternation shall occur.
4. When a pump run verification signal is not received within the appropriate time period, the alternator shall deselect the failed pump, select the next pump, remove the failed pump from the sequence, and illuminate the failed pump light. The failed pump shall remain out of service and the failed pump light shall remain illuminated until manually reset.
(b) Terminal blocks for incoming power, pump power conductors, level sensors, leak detectors, motor thermal sensors, and control wiring.
(c) Circuit breakers with over-current protection for each of two pumps and the convince power transformer. Circuit breakers shall be magnetic-hydraulic or thermal magnetic, ambient temperature compensated type, calibrated and factory sealed with the proper trip settings. The devices shall have a minimum interrupting rating of 10,000 RMS symmetrical.
(d) Magnetic full voltage starters for each of two pumps. The starter overload relays (one per phase) shall be ambient compensated, quick trip type. Overload elements shall be matched to the motor characteristics.
(e) Convenience and control power transformer with 460 volt primary and 120/240 volt secondary rated at 2WK (where required due to the three phase service).
(f) Convenience power distribution panel (30A, 1201240V, 1PH-3W) with main breaker and 20A, IP branches. Circuit breakers operators shall be accessible without opening the deadfront “operator’s door”. Branch breakers shall be supplied as follows: one for control; one for GFI receptacle; and one for condensate heater.
(g) GFI type duplex convenience receptacle (120V, 20A) mounted on the dead front operators door.
(h) A low volt power supply and interface suitable for operation of the float switches in an intrinsically (explosion proof) safe mode.
(i) An adjustable thermostatically controlled heater to provide condensate protection inside the enclosure.
(j) Two pump automatic electronic alternator, which will alternate the pumps with each pump down cycle.
(k) The pump controller shall provide relay outputs to interface with the motor control devices as required.
(l) Running time meters for each pump. The meter shall indicate the number of hours of pump operation. The meter shall be enclosed in a dust and moisture proof molded plastic case. The flush mounted dial shall register in hours and tenths of hours up to 999.9 hours before repeating.
(m) The control panel shall provide the following status/alarm indications for each pump:
1. Pump running light (green);
2. Pump failed light (red);
3. Seal failure; and
4. High wet well level.
(n) In addition, the panel shall have a hand-off-auto selector switch for each pump to control mode of pump operation and timing modules as required for the pump failed feature.
(o) The local alarm system shall consist of an alarm light and shall signal any of the above alarm conditions.
(p) The alarm light shall be a weatherproof high intensity strobe fixture with a red lexan globe guard mounted on top of the enclosure.
(4) Level sensors.
(a) The level sensors shall consist of weighted floats with mercury contacts rated for low volt operation at milliwatt levels. Each level sensor shall be furnished complete with sufficient cable length to run to the terminal box below the pump station controller and leave slack for future level adjustment.
(b) Floats shall meet the requirements for Class 1, Division 1, Group C&D, and be intrinsically safe for installation in an explosion hazard environment.
(c) Floats shall operate at a maximum of 24 volts.
(d) Furnish a stainless steal bracket mounted in the hatch opening for hanging the sensor cables.
(D) Lift station piping.
(1) Interior lift station and valve pit piping shall be flanged ductile iron, centrifugally cast conforming to the latest revisions of ANSI/AWWA C150/A21.50 and ANSI/AWWA C151/A21.51. The interior surface of the pipe cement lined and seal coated in accordance with ANSI/AWWA C104/A21.4. Pipe shall be pressure class 250 minimum.
(2) Flanges shall be of 250 psi working pressured, drilled at ASA 125 pounds standards and meeting the requirements of ANSI/AWWA C111/21.10.
(E) Valves.
(1) General.
(a) All valves shall be furnished with an exterior finish coating the same as the adjacent piping system to which they are connected or as approved by the engineer.
(b) All valves of the same type shall be of the same manufacturer.
(c) Where required for satisfactory operation of valves, provide extension stems, stem guides, cast iron valve and curb boxes, floor boxes, and other valve appurtenances. Extension stems shall be complete with guide bearings, wrench nut, and tee handle wrench. All valve stems and machinery stuffing boxes shall be packed material as selected for the intended service. All valves shall be designed for repacking.
(d) Tee wrench operators shall be provided as required for proper operation.
(2) Plug valves.
(a) Plug valves shall be the non-lubricated, resilient seated, eccentric type.
(b) All plug valves shall be the size indicated on the drawings. All plugs shall be of the drip-tight-closing, resilient faced plug type, and shall be of the eccentric seating construction such as the operating unit of the closing member (plug) results in the closing member rising off the body seat contact. Port areas shall be equal to at least 80% of the nominal pipe size area.
(c) Valve bodies, bonnets, and plugs shall be constructed of cast iron meeting the requirements of ASTM A126 Class B.
(d) Valves shall be rated 175 psi up to 12 inches and 150 psi for valves 14 inches and larger. An adjustable close position stop shall be provided for field adjustment. The seat end and standard low direction shall be cast on the valve body.
(e) All shaft seals shall be replaceable without disassembling the valve and while the valve is under system operating pressure.
(f) The plug shall be of a one-piece design with a precision molded resilient facing. The resilient seating surface shall not be in the flow way pattern when the valve is in the open position. The body-seating surface shall be welded nickel overlay containing a minimum of 90% nickel.
(g) Radial journal bearings shall be stainless steal, of the permanently lubricated type. Two thrust bearing shall be provided in the upper journal area, one of stainless steal and one of Teflon. The lower journal shall have one stainless steal thrust bearing of the non-adjustable type. Grit seals shall be furnished in the upper and lower journals to prevent abrasive media from entering the bearing and seal areas.
(h) Unless otherwise noted or shown, all valves and connections shall be ANSI Class 125 flanges.
(i) Valves shall be series 5000 as manufactured by Val-Matic Valve & Mfg. Corp., Series 100 as manufactured by Dezurik, or equal.
(3) Rubber flapper swing check valves.
(a) Swing check valves shall have a cast iron body and cover meeting the requirements of ASTM A126, Class B. The valve body shall have full flow equal to the nominal pipe diameter at any point through the valve. Valve shall be designed for a 175 psi minimum working pressure.
(b) The valve-seating surface shall be on a 45-degree angle to minimize disc travel. The disc shall be of one-piece construction, precision molded with an integral o-ring type-sealing surface. The disc shall be made of Buna-N and have a non-slamming characteristic by means of a 35 degree disc stroke and disc return action.
(c) The top access port shall be full size, allowing removal of the disc without removing the valve from the pipeline.
(d) The check valve shall have backflow capabilities by means of a screw type backflow actuator.
(e) The interior of the valve shall be coated with epoxy suitable for portable water.
(f) Unless otherwise shown or noted, the check valve end section shall be ANSI Class 125 flanges.
(g) Rubber flapper swing check valves shall be as manufactured by Val-Matic Valve and Manufacturing Corp. or equal.
(4) Mud valves. Valves shall be of spigot end, non-rising steam design having a cast iron body. The stem, stem nut, seat ring, and disc ring shall be made of bronze. All bolts and nuts shall be of corrosion-resistant steal. Valves shall be furnished complete with extension steam having a two- inch square as required for the application. Each valve is to be furnished with a tee handle wrench of length as required by drawings. Mud valves shall be Model F-3080 as manufactured by Clow or equal.
(Ord. passed - -)