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SUBMERSIBLE PUMPS 1.1 SUBMERSIBLE PUMPS A. General: The CONTRACTOR shall furnish submersible pump complete with water cooled motor, check/drain valves, discharge column, submersible pump cable, two air lines, pressure transducer, new pitless unit O-rings, and miscellaneous appurtenances complete in operating order. B. Operating Conditions: The pump will be used for pumping clean groundwater into a transmission and storage system. The pump shall meet the operational and dimensional requirements for the well as listed in the following sections. C. Performance and Equipment Requirements: Capacity at Rated Head, gpm 1,100 Rated Head, feet 600 Pumping Operating Speed at Rated Head, rpm 3,450 Minimum Motor HP 200 Motor Safety Factor 1.15 Minimum pump efficiency at Rated Head, % 83 Minimum Discharge Diameter 8-inch, NPT Pump Intake Setting Below Grade 450 feet Column Size - existing 8-inch NPT, Sch. 40 Steel Motor 6-inch, 460 volt, 3 phase Cable (3 wire w / ground) 75°C, 350 MCM, 361 Strand, Copper 1.2 PUMP REQUIREMENTS A. Pump Element: The pump shall be a multi-staged turbine, designed for operation at 3,450 rpm. The impellers shall be the enclosed type, constructed of stainless steel or other ENGINEER-approved material. They shall be accurately fitted, smoothly finished, and dynamically balanced at normal pump speed. The bowl cases shall be constructed of stainless steel. B. Pump Shaft: The pump shaft shall be of stainless steel. C. Bolts: All screws, bolts, and nuts shall be of stainless steel. D. Check and Drain Valves: A combination check and drain valve shall be installed on the joint above the top of the pump to prevent water from flowing backwards through the pump and to avoid pulling the pump with the drop pipe full of water. The check and drain valve shall be designed for the length of setting, flow rate, and pressures to be encountered. Two additional brass or monel break-off plugs shall be provided. A check valve shall be installed in the pump column one joint below the pitless adaptor. The check and drain valves shall be sized to couple directly to drop pipe without fittings or swedges. The manufacturer of the check and check/drain valves shall be Simmons, Part No. 2687SB, or ENGINEER approved equivalent. ---PAGE BREAK--- 1.3 MOTOR, CABLE, AND CONTROL UNIT A. Motor: The 8-inch submersible pump motor shall be constructed of cast iron or carbon steel and stainless steel and shall be of the water filled, squirrel cage induction type suitable for across the line starting, designed for and rated for 460 volts + three phase, 60 hertz, with normal torque and low starting current. The motor maximum operating horsepower shall not exceed nameplate horsepower including service factor. The motor shall be capable of continuous operation at nameplate rating in a submerged condition at a maximum water temperature of 167° F. The motor shall be equipped with a continuous duty Kingsbury type axial up thrust bearing to protect against running up thrust. All bearings shall be designed for a minimum B-10 service life of 60,000 hours. Down thrust and up thrust bearings shall be mounted at the top of motor to ensure motor stability. The motor shall be equipped with a mechanical seal to prevent intrusion of abrasives or other water-borne contaminants. The motor shall have a service factor of 1.15. The pump to motor coupling shall be of AISI 316 stainless steel. The pump motor shall be as manufactured by Franklin, Hitachi, or ENGINEER approved equivalent. The pump motor shall be capable of operation with a variable frequency drive motor controller. B. Submersible Cable: Submersible cables shall be sized for the specific motor supplied and for the conditions under which the motor is designed to operate. The cable shall be flat, copper with 4 conductors contained in a single overall jacket. The fourth wire shall be installed as a separate ground to motor as required by code. The pump cable shall be minimum 361 strand conductor. The cable shall be one piece from the motor splice to 25 feet above ground. Approved water-proof splices shall be made at the motor pigtail connections. C. Banding: Banding of motor cable and airlines shall be every 10-feet using ¾-inch, stainless steel bands, fasteners, and fittings. All downhole cables and airlines shall be protected from the stainless steel bands with approved protectors. 1.4 WATER LEVEL INDICATOR A. Two airlines shall be installed with the pump. Airlines shall be one piece, 1/4-inch O.D. or less polyethylene, with a burst strength of not less than 500 psi. Airlines will be terminated in the top of the well casing. B. The transducer shall be a DynoTek Slimline submersible pressure transmitter with a 4-20 mA output and a 0-100 psi pressure range, or ENGINEER approved equivalent. The transducer cable shall be vented and of sufficient strength to hold the weight of the cable and transducer. The transducer sensor cable shall be extended in a watertight conduit from the pitless adapter to an enclosure adjacent to the wellhead. C. The airlines and transducer cable shall be securely fastened with vinyl tape beneath stainless steel bands to the column pipe and care shall be exercised in lowering the pump assembly so that the airlines and transducer cable are not damaged. The transducer cable shall be installed on the opposite side of the pump column pipe from the motor cable. D. The airlines and well water level sensor shall be attached to a depth equal to the bottom of drop pipe. 1.5 PUMP AND MOTOR MANUFACTURERS A. Submersible Well Pump: Grundfos 10RJMC-4, 6-stage, or ENGINEER-approved equal. ---PAGE BREAK--- B. Submersible Pump Motor: Franklin or Hitachi 8-inch 200 HP, 460-volt, 3-phase, or ENGINEER-approved equal. EXECUTION 2.1 PUMP INSTALLATION A. Pumping equipment shall be installed in accordance with approved industry standard procedures, unless otherwise approved. B. Operational Testing: Equipment shall be field tested to verify proper operation as specified, and freedom from binding, scraping, vibration, or other defects. Pump drive shafts shall be measured just prior to assembly to ensure correct impeller spacing. Equipment shall be secure in position and neat in appearance. C. Column pipe shall be torqued to manufacturer’s standards to prevent "unscrewing". Joints shall be lubricated with joint compound approved for use in public drinking water wells. Check valves will be field tested for performance in the presence of the OWNER prior to installation in the pump column pipe string. D. Pump and motor shall be assembled and mechanical alignment maintained to prevent undue stress on motor and pump shaft. Stainless steel bolts shall be torqued to manufacturer's recommendations. The motor cable shall be spliced to motor lead provided by motor manufacturer and in junction box at the top of the pitless adapter. The motor lead splice shall comprise of crimped or soldered connectors and insulated with heat shrink rubber and plastic electric tape to manufacturer's recommendations. The upper splice may be made with insulated split bolts or with insulated screw-lug type connectors and must be made in a new junction box adjacent to the wellhead. All splices shall maintain electrical insulation as good as or better than insulation of pump cable. Ground wire shall be connected directly to the frame of submersible motor. All motor fluids shall be checked as per manufacturer recommendations prior to installation. E. New pitless spool O-rings shall be used in the installation of the pumping equipment. At the request of the OWNER, the CONTRACTOR may be required to cut the existing lifting sub and weld a 4-inch swedge with a 4-inch threaded coupling, new 4-inch pipe and lifting ring to facilitate installation of the pump cable through the pitless to a new junction box. F. The well pump and related equipment shall be disinfected according to AWWA C-654-97 standards prior to placing well in service. After final flushing and no detectable chlorine residual, and before piping is placed in service, a sample, or samples shall be collected from the end of the line, and shall be tested for bacteriological quality in accordance with the requirements of the State Department of Health or other appropriate certified, regulatory agency. For this purpose the pipe shall be re-filled with fresh groundwater and left for a period of 24 hours before any sample is collected. Should the initial disinfection treatment fail to produce satisfactory bacteriological test results, the disinfection procedure shall be repeated until acceptable results are obtained.