In House Dynamic Balancing



Why Dynamic Balancing?

Dynamic balancing is a way of balancing machines by rotating parts quickly and measuring the imbalance using electronic equipment. The imbalance measured can then be corrected by adding or subtracting weight from the rotating parts until the vibration is reduced.
Basically, all machines have some form of residual vibration. Enormous vibration in rotating machinery can cause high levels of noise and more importantly, significantly reduce the life of components. So, the ideal thing to do would be to remove all causes of vibration and allow the machine to run completely smooth. The process of balancing is the removal or addition of weight to the device, so that this effective mass center approaches the true axis.
Causes of Unbalance
Material problems such as density, porosity, voids and blow holes can contribute to the unbalance condition. Fabrication problems such as misshapen castings, eccentric machining and poor assembly.
☛   Distortion problems such as rotational stresses, aerodynamics and temperature changes.
☛   Corrosion.
☛   Wear.
☛   Distortion.
☛   Deposit build up dirt and deposits can break off unevenly, which can lead to severe unbalance, this especially applies to fans, blowers, compressors and other rotating equipment process variable.
Rotors that operate within 70%-75% of a critical speed are considered flexible rotors. Rotors that operate below that speed are considered rigid. Many times rotors are balanced at the factory for a rigid condition using a low speed balancing machine, but when the get put into service they become flexible rotors. These flexible rotors require a multi plane balancing procedure.
Correcting Unbalance
When unbalance has been identified, the correction is straightforward weight has to be added or removed from the rotating element. The goal is to reduce the uneven mass distribution so that centrifugal forces and vibrations induced in the supporting structures are at an acceptable level.

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