The structure of balancing machine
Balancing machine is composed of mechanical part, electrical control part and electrical measuring part. The three parts work together and no one is dispensable.
The mechanical part supports the rotor and generates a vibration signal.
The electrical control part drives the rotor to certain speed.
The electrical measuring part processes vibration signal of rotor, changes it to unbalance value and displays it to users
Horizontal balancing and vertical balancing
The balancing machine which rotor is placed in the horizontal position is called horizontal balancing machine.
The balancing machine which rotor is placed in the vertical position is called vertical balancing machine.
Single plane and double plane
The plane which can adjust weight (add or loss) on the rotor is called correction plane. To do balance on one correction plane is called single plane balancing. To do balance on two correction planes is called double plane balancing.
In theory, any rigid rotor needs to be done double plane balancing to achieve balance, but in practice, for some thin disc type rotors, we only do single plane balancing.
Static unbalance and couple unbalance
The unbalance of the rotor can be decomposed into a vector and a moment of couple. The vector is called static unbalance. The moment of couple is called couple unbalance. Single plane balancing can only eliminate static unbalance.
Dynamic balancing and static balancing
To do static balancing, the rotor is usually put on two level rail or two bearings to finish balance rely on gravity. Static balancing only can eliminate static unbalance.
To do dynamic balancing, the rotor should be put on the balancing machine and rotated to certain speed. Dynamic balancing can eliminate both static unbalance and couple unbalance.