You have vibration problems
YOU HAVE VIBRATION PROBLEMS ST018_5
There are several different types of vibration that include:
- Mechanical causes of vibration
- Unbalanced rotating components. Damaged impellers and non-concentric shaft sleeves are common.
- A bent or warped shaft. This often happens during the removal of the shaft sleeve, the bearing, or the mechanical seal.
- Pump and driver misalignment.
- Pipe strain. Either by design or as a result of thermal growth.
- Thermal growth of various components especially shafts.
- Rubbing parts.
- Worn or loose bearings.
- Loose hold down bolts.
- Loose parts.
- The product is attaching to a rotating component, probably the impeller.
- Damaged parts.
- There is not enough mass or weight in the pedestal. If you weigh the pump and its driver there should be a least five times that mass in the pump pedestal.
- The pedestal is not wide enough. If you drop a vertical line from the center of the motor, two lines radiating out thirty degrees from this centerline should pass through the base, not the sides of the pedestal.
- Hydraulic causes of vibration
- Operating off of the best efficiency point (BEP) of the pump.
- Vaporization cavitation.
- The impeller vanes are running too close to the pump cutwater.
- Internal recirculation
- Air is getting into the system through vortexing etc.
- Turbulence in the system (non-laminar flow).
- Water hammer.
- Other causes of vibration.
- Harmonic vibration from nearby equipment.
- Operating the pump at a critical speed. Watch out for this problem in variable speed and pulley driven pumps.
- Seal “slip stick” at the seal faces.
- The product is vaporizing at the seal faces
- A pump discharge recirculation line is aimed at the seal faces. Each pass of an impeller vane gives a pulse to the fluid going to the stuffing box.
- On February 18, 2018