2008-213 - Laserfiche WebLink

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A. The pumps shall be totally submersible, non-clog, centrifugal pumps with close-coupled motors designed to pump sewage. The pumps shall be capable of passing a minimum 3 - inch diameter spherical solid. The motor shall be an integral part of the pumping unit. The design shall be such that the pumping units shall be automatically connected to the discharge piping when lowered into place on the discharge connection. The pumps shall be easily removable for inspection or service, requiring no bolts, nuts or other fastenings to be removed for this purpose, or need for personnel to enter the wet well . B . At the rated rpm, each Humping unit shall have the following operating performance : Flow Npm) Total Head (ft.) 0 36 80 32 190 26 The pumps shall be as manufactured by " ABS " , model AFP 1040 , with 177 mm impeller, or approved equal. I J C. Pump Construction - The pump shall be of the centrifugal type with a solids handling, single vane, dynamically balanced, shearing type impeller. The common pump and motor shaft shall be series 400 stainless steel. The shaft and rotor assembly shall be supported by two ball bearings; the lower ball bearing shall be a heavy duty, double row, angular contact ball bearings. Each pump shall be provided with a tandem double mechanical seal running in an oil reservoir, composed of two separate lapped face seals, each consisting of one stationary and one rotating tungsten-carbide or silicon carbide ring with each pair held in contact by a separate spring, so that the outside pressure assists spring compression in preventing the seal faces from opening. The compression spring shall be protected against exposure to the pumped liquid. The pumped liquid shall be sealed from the oil reservoir by one face seal and sealed from the oil reservoir from the motor chamber by the other. The seals shall require neither maintenance nor adjustment, and shall be easily replaced. Conventional double mechanical seals with a single spring between the rotating faces, requiring constant differential pressure to effect sealing and subject to opening and penetration by pumping forces, shall not be considered equal to tandem seal specified and required.The impeller shall be constructed of nodular iron SP. All other parts shall be of close grain gray iron construction, with all parts coming into contact with sewage protected by a coat of rubber- asphalt paint. All external bolts and nuts shall be of stainless steel. D . Pump Identification - Stainless steel nameplatesgiving the name of the manufacturer, head, speed, and all other pertinent data shall be attached to each pump and motor. 2 .03 PUMP MOTORS AND CABLES A. Pump motors shall be of the submersible type, housed in an air-filled, watertight casing. Motors shall be a NEMA Design B . Insulation shall be moisture-resistant NEMA Class F with a maximum temperature rise of 90 degrees Celsius above ambient temperature (40 degrees Celsius) . The motor shall be rated for a maximum of 3 .0 Hp at 1780 RPM, connected for operation at 230 volt, 60 hertz, 3 -phase service . The motor shall be non-overloading along the entire operation of the published pump curve. The full load current shall not exceed 10 .0 amps at 230 volts, 3 phase, electric service . Pump motors shall have cooling characteristics suitable to permit continuous operation, in a totally, partially or nonsubmerged condition. Each motor shall incorporate an ambient temperature compensated overheat sensing device and a moisture sending device wired in series. The protective devices shall be wired into the 025394 02539 - Submersible Pump Station (Rev.)