Centrifugal pump vibrations the causes 02 2003

Centrifugal Pump Vibrations: The Causes by Steven J Hrivnak, P.E Associate Mechanical Engineer Tennessee Eastman Eastman Chemical Company EASTMAN FAULTS REPORTED OVER YEARS Vibration: a measure of reliability! Poorly installed and operated pumps average 178 in/sec overall vibration and have months life Properly installed pumps average 071 in/sec overall vibration and have 60 months life EASTMAN Three Basic Causes of Pump Vibrations: • Mechanically Induced • System Induced • Operation Induced Mechanically Induced • Bad bearings • Bent Shaft • Unbalanced Rotor • Check Valve Installed Backwards • Mis-Alignment • Looseness • Soft Foot • Maximum Size Impeller System Induced • Partially/Plugged Strainer • Clogged Impeller or Suction Line • Installation PIPING? Speed Suction Pipe Immersion Conclusions Avoid Max Size Impellers EASTMAN Conclusions Avoid Max Size Impellers Keep speed to 1750 max EASTMAN Conclusions Avoid Max Size Impellers Keep speed to 1750 max Keep flow in design range EASTMAN Conclusions Avoid Max Size Impellers Keep speed to 1750 max Keep flow in design range Grout your baseplates EASTMAN Conclusions Avoid Max Size Impellers Keep speed to 1750 max Keep flow in design range Grout your baseplates Use proper piping EASTMAN Conclusions Avoid Max Size Impellers Keep speed to 1750 max Keep flow in design range Grout your baseplates Use proper piping Avoid hydraulically induced problems like cavitation, and suction and discharge re-circulation, submergence EASTMAN 55PUMPS PUMPS- -66YR YR.MTBF MTBF 88PUMPS PUMPS- -55YR YR.MTBF MTBF 15 15PUMPS PUMPS- -44YR YR.MTBF MTBF ... operated pumps average 178 in/sec overall vibration and have months life Properly installed pumps average 071 in/sec overall vibration and have 60 months life EASTMAN Three Basic Causes of Pump Vibrations: ... Mis-Alignment • Looseness • Soft Foot • Maximum Size Impeller System Induced • Partially/Plugged Strainer • Clogged Impeller or Suction Line • Installation PIPING? Foundations and Baseplates The. .. Impeller Life Discharge Recirculation Flow B.E.P Low Bearing and Seal Life Cavation Operating Off The B.E.P Suction Recirculation