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2 .04 MELLER <br /> A. The impeller shall be of one piece cast bronze, double suction type . The impeller shall be <br /> balanced , keyed to the shaft and fixed in an axial position by threaded shaft sleeves . The <br /> impeller skirt shall be grooved and fit with close tolerances to the casing ring to pemut a <br /> minimum of recirculation between the impeller and the casing ring for maximum efficiency . <br /> Renewable bronze impeller rings shall be shrunk on the impeller and locked in place with <br /> stainless steel set screws . <br /> 2 .05 BEARINGS <br /> A . Bearing shall be single row, deep groove ball type ; the inboard bearing shall be arranged for <br /> radial loads only. The outboard bearing shall be arranged for both radial and axial loads . <br /> Both bearings shall be arranged for both radial and axial loads . Both bearings shall be grease <br /> lubricated with grease flush through the bearing housing. Bearings shall be designed for an <br /> average life of 250,000 hours . <br /> B . Outboard bearing cover shall have a plugged opening for tachometer connection . Bearing <br /> housing lubrication design must be capable of being changed from grease to oil lubrication <br /> type without replacement of bearing housing or the lower pump casing . The outboard <br /> bearing shall have retaining ring retention . <br /> 2 .06 SHAFTING <br /> A. The shaft shall be carbon steel (SAE 4140), adequately sized for the loads transmitted. Shaft <br /> deflection shall not exceed .002 inches at the face of the stuffing box when operating <br /> between 95% and 105% of capacity at best efficiency at the pump ' s maximum 60 Hz. Speed <br /> and with full diameter impeller. The shaft shall be protected through the stuffing box by <br /> means of bronze shaft sleeves and they shall be threaded against shaft rotation. The sleeves <br /> shall be sealed at the impeller hub by a Teflon coated steel gasket to prevent pumped liquid <br /> between the shaft and sleeve . Shaft sleeves shall extend beyond the mechanical seal flanges. <br /> 2.07 STUFFING BOXES <br /> A. Sealing of the pump liquid cavity shall be with a face type mechanical seal with Ni-resist <br /> stationary seat, carbon sealing washer, Buna rubber flexible members, stainless steel metal <br /> parts and spring. Seal to be rated for 225 degree Fahrenheit. (107 degrees. Celsius) @ 150 <br /> psig maximum. Seal shall be mounted over a bronze shaft sleeve. <br /> 2.08 BASE <br /> A. The pump and driver shall be mounted on a common cast iron base with drip rim. Pump and <br /> driver shall be aligned and bolted in place prior to factory shipment. Final alignment must be <br /> performed at the jobsite in accordance with the standards of the Hydraulic Institute and the <br /> pump installation, operation and maintenance instructions . Base is to be grouted to eliminate <br /> vibration . <br /> i <br /> 044572017 <br /> 1193" <br />