2008-276 D - Laserfiche WebLink

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