Machines are typically balanced in one plane or two planes by adding or removing material. The previous article titled “Balancing in Manufacturing“, mentioned different types of imbalance in rotating machinery, and the importance of why machines have to be balanced. The question is: How do we know if a machine needs to be balanced in one plane or two planes?
Selecting one plane or two plane balancing is not straightforward. It generally depends on two factors. One of the factors is the ratio of the length of the rotor (L) to the diameter of the rotor (D). The other factor is the operating speed of the rotor. As a general rule of thumb, we can refer to the table shown below.
There is, in fact, no clear distinction when one has to perform one plane or two plane balancing. It is a common practice in industries to perform one plane balancing in relatively narrow rotors. This is due to fact that the rotor weight distribution relatively parallels to the axis of rotation, which is also known as static imbalance.
Patented XYO technology provides a solution in reducing or eliminating vibration by automatically balancing rotating equipment in many applications. Some of the applications are:
One plane balancing – angle grinders, optical disk drives, and boat propellers.
Two plane balancing – washing machines and driveshafts
Note that fans can be balanced in one plane or two planes, depending on the L/D ratio.