Centrifugal PumpCentrifugal Pump

Impeller/Wear Rings/CasingImpeller/Wear Rings/Casing Wear & tearWear & tear ClearancesClearances

ShaftShaft Wear & tearWear & tear AlignmentAlignment ““ringing” soundringing” sound

Gear PumpGear Pump Gears/CasingGears/Casing

Wear & tearWear & tear ClearancesClearances

BacklashBacklash Gear/casingGear/casing Gear shaft/bushGear shaft/bush Bush/casingBush/casing

Safety ValveSafety Valve ConditionCondition

Screw PumpScrew Pump

Screws/casing/timing gearsScrews/casing/timing gears Wear & tearWear & tear ClearancesClearances

ScrewsScrews Timing gearsTiming gears

““ringing” soundringing” sound Safety ValveSafety Valve

conditioncondition

Mono PumpMono Pump

Stator/rotorStator/rotor conditioncondition

Safety valveSafety valve conditioncondition

ShaftShaft conditioncondition

Pump & Line BearingPump & Line Bearing

Two Stage Single Impeller

Line BearingsLine Bearings

TeflonTeflon ElastomerElastomer PolyesterPolyester CarbonCarbon SimsiteSimsite

Provided in the volute cover/fitted onto the Provided in the volute cover/fitted onto the shaftshaft

Held by cover or set screwsHeld by cover or set screws Keep shaft steady by taking up the radial Keep shaft steady by taking up the radial

deflectiondeflection Will fail first, prevent further damages esp. to Will fail first, prevent further damages esp. to

the shaftthe shaft Have axial grooves for lubrication by pump Have axial grooves for lubrication by pump

dischargedischarge Made of self-lubricating material Made of self-lubricating material May have stainless steel outer shellMay have stainless steel outer shell

CharacteristicsCharacteristics

Self LubricatedSelf Lubricated Resist corrosion, erosion and do not support Resist corrosion, erosion and do not support

electrolysiselectrolysis Highly polished surface to reduce wear on Highly polished surface to reduce wear on

shaftshaft Withstand high temperatureWithstand high temperature Have good mechanical strength to withstand Have good mechanical strength to withstand

loading and torqueloading and torque

Should have rigidity to reduce radial Should have rigidity to reduce radial movement, vibration & noisemovement, vibration & noise

Accommodate precision machining for tight Accommodate precision machining for tight clearance and correct alignmentclearance and correct alignment

Lend itself easily to custom modificationLend itself easily to custom modification Low wear giving longer service lifeLow wear giving longer service life ““Non-seizing” – i.e. will not seize on shaftNon-seizing” – i.e. will not seize on shaft

DisadvantagesDisadvantages

Prone to cracks due to unbalance load Prone to cracks due to unbalance load Custom designCustom design High costHigh cost Plastic, elastomer, rubber will meltPlastic, elastomer, rubber will melt Cannot be repaired onboardCannot be repaired onboard