Crane's Fluid Connection Blog | Fluid Handling Tips

What To Consider When Selecting Pump Couplings

Written by Morgan Falck | June 22, 2017

 

As mentioned in the “Quick and Dirty Guide to Pump Coupling Types”, the coupling selection for your pump will help determine how efficiently your pump runs.  To review, pump couplings connect the pump shaft and motor shaft together, in order for the motor to efficiently transmit power to the pump.  

If your pump’s coupling isn’t selected with care and consideration for your pump it will not run with the accuracy and dependency that your operation requires.   So what should be considered when selecting your pump's coupling?  Take a peek at our list below!

  • Horsepower & operating speed- HP and speed are used to calculate torque. Every coupling will have a maximum torque rating and max HP/100 RPM rating. These maximum ratings will depend on the manufacturer and type of coupling.  HP and speed are required to calculate these values and size the coupling.  
  • Ambient Temperature- All materials used in couplings will have some sort of min/max temperature limits. As long as your selection is within that materials limits, you should be fine, but you should consider that thermal expansion/contraction on the components that you are coupling together can occasionally play a factor. 
  • Space Limitations- Each coupling will be able to accept a specific range of distance between shaft ends (“DBSE”). Depending on the pump (or other equipment) design, it may be beneficial (or required) to increase or decrease that distance. 
  • Angular / Offset Misalignment & Axial Travel- Each coupling will have limitations on how much misalignment it can take (based on type, mfg., etc.) Too much misalignment will cause premature coupling failure.

Selecting pump couplings is often done as an afterthought during the pump selection process,—but it is an important aspect to consider.  If you still aren’t sure what coupling is best for your pump check with one of our experts!