L-4089 - SHURflo Industrial

SHURflo Operating Instructions, Performance,Specifications and Parts ManualViton Models GMSV2A, GMSV4A, GMSV6C, GMSV2A3T, GMSV2A33T,GMSV4A5T, GMSV4A53T, GMSV6C7T and GMSV6C73TTeflon ® Models GMST2A, GMST4A, GMST6C, GMST2A3T, GMST2A33T,GMST4A5T, GMST4A53T, GMST6C7T and GMST6C73T4. Recheck motor and pump rotation.Pump rotation is by-directional(See Figure 1).PRESSURE RELIEF VALVE5. Standard models do not include apressure relief valve. If discharge isgoing to be shut off, an externalpressure relief valve should beinstalled.GEAR PUMP GASKET ADJUSTMENTFOR TEMPERATURE (See Appendix 1)6. For operation in fluid temperaturesabove 120° F, stainless steel pumpmodels must have the gasket thicknessadjusted. Use Appendix 1 toidentify pump, temperature andgasket recommendations for adjustingthe cover clearance prior tooperation in elevated temperaturesor viscosities above 500 SSU.Failure to adjust pumpcover clearances foroperating temperatures above 120° F. willresult in severe pump and/or motor damage.NOTE: When pumping fluids of highviscosity (>500 ssu), the required torqueand HP can be reduced by adding agasket for increased gear clearance.MECHANICAL SEAL FLUSHINSTALLATION OPTIONS7. These stainless steel pumps areequipped with mechanical seals andhave been designed with flush portsbecause mechanical seals requirecooling lubrication for long life.a. For fluids with viscosities less than2000 SSU, a flush is not necessary,but the seal cavity must be prefilledwith either the operatingfluid or a neutral fluid. This is toensure seal cooling and lubricationduring start-up (See Figure 5).Failure to provideinitial seal prime canresult in the mechanical seal overheatingwith resulting repair costs.b. For high viscosity fluids, a flushwill be necessary. The seal mustbe cooled and lubricated by afluid. In the case of high viscosityfluids, due to the precision clearancesbetween the gear teeth andthe stainless steel body, highlyviscous fluids will not be able toadequately relieve the air in theseal cavity on start-up. The dryrunning of a mechanical sealwill cause rapid failure. A flushmust be provided for fluids with aviscosity of greater than 2000 SSU.Pumping fluids withviscosities greater than2000 SSU requires flushing the seal chamberduring operation, otherwise seal damagewill occur.EXTERNAL FLUSHAn external flush system is typicallyrecommended for applications wherecrystallization build-up on the seal ispossible. Some dilution of the workingmaterial must be acceptable to use anexternal flush system.The external flush system (See Figure 6for typical installation) is commonlyused with liquids where city water canbe used as the neutral flush fluid. Citywater is taken from an external sourcesuch as a tap, hose, or special plumbingfixture and is regulated into the sealcavity by means of a needle valve andflow meter. Use of an anti-siphon checkvalve is required.SuctionDischargeSuctionDischargeSeal CavityCheck ValveNeedle ValveSeal CavityNeedle ValveFlow MeterFlow MeterFigure 6 - External FlushFigure 7 - Internal FlushForm L-4089 (12/09)9