Supply and delivery of 12HP Submersible Sewage non-clog pumpset and fixing of non return valve at Thriuvallur Nagar Pumping Station in Zone 2

Amount

Supply and delivery of submersible centrifugal sewage non-clog pumps (Discharge 20 to 100 M3/hour, above 15m upto 20 m head) vertical spindle type pump, wear resistance with submersible motor for the various duty conditions. Pump shall be capable of handling min 100 mm solid size with sewage specific gravity of up to 1.05 Pump shall be of robust construction, Liquid passages shall be finished smooth and designed as to allow free passage to solids. Pump Impeller should be of Non-clog semi open type, single vane / multi vane preferably contra bloc or vortex impeller design. Double mechanical seal with silicon carbide faces should be provided to protect the motor from ingress of sewage along the shaft. The critical speed of the rotor shall be at least 30% above the operating speed. Pumps should have double bearings between the pump & motor. The bearings life shall be minimum 100,000 hrs of peration with greased for life. Pump should be provided with automatic coupling device including pedestal, duck foot bend, stainless steel guide pipe or related accessories of suitable size to facilitate lifting and lowering into uide rails for easy maintenance. Pump shall be provided with a stainless steel lifting chain conforming to BS 970 Gr 304. Pump speed shall be of 9600 rpm for high duty pumps and 960/1450 rpm for low duty pumpsets. Casing and impeller should be of CI Gr. FG 260:IS210 more preferably with hardened impeller.Shaft should be of stainless steel AISI 410. All the fasteners and bolts shall be of AISI 410.The submersible motor shall be operated with 3ph, 415 V (+or– 10%), 50Hz (+or-5 %) dry induction type. Motor shall be capable of giving rated output without reduction in the expected life span when operated continuously. The rotating assembly shall be dynamically balanced as per standards. The starting current of the motor shall not exceed 200% of rated full load current for Star / Delta or ATS starting under any circumstances .The motor shall be suitable for full voltage star delta / ATS starting. The locked rotor current of the motor shall not exceed 600% of full load current unless otherwise specified. Motor shall be designed to withstand 120% of rated speed for two minutes without any mechanical damage, in either direction of rotation. The motor vibration shall be within the limit specified in applicable standards. Motor should be of IE2, explosion proof compatible for VFD operation together with star-Delta /ATS starter, protection against increase in stator winding temperature (15 deg Celsius), bearing temperature, leakage in the stator housing and terminal box shall be provided and to be suitably interlocked with the control panel for tripping the pump in case of increase in temperature beyond set limit.

Labour charges for the erection of submersible pumpset in borewell/openwell including fixing and jointing submersible cable with proper clamps upto the starter to required depth and also fixing of riser pipes to the required depth valves erection clamps, pressure gauges upto the exterior wall of pump room and erection of panel board consisting of TPICN switches starter, Voltmeter, Ammeter, three pilot (indicating) lamps capacitor single phasing preventor, water level guard and laying and jointing the cables and twin earthing as per IE rules etc., complete and testing the pumpset and trail run for 10 days.

Guru Engineers (BID ID -1565635)

PNP CONSTRUCTIONS (BID ID -1564137)

J.Thirunavukkarasu (BID ID -1565570)