Wheel rotor:
There is only one transverse unbalanced planar rotor. This kind of rotor only exists in one known plane because of the unbalanced quantity. Therefore, it only needs to be measured on the balance in the low-speed dynamic balancing machine. Not the same balance at speed.
Pulley wheel:
   The plane rotor has two lateral imbalances, and the two planes in which the imbalance value is located are known, so it is not necessary to make an unbalanced measurement in the two planes on a low-speed dynamic balancing machine. Meet the balance requirements at the speed of rotation.
   Compressor rotor:
   This is a rotor with more than two transverse planes. After the rotor is assembled from two or more parts along the axial direction, it can be considered that each spare part is an unbalanced plane, before installation. For each of the spare parts, a fine balance measurement is made, or the side mounting balance is selected, so that the balance is only required to be measured on the two correction surfaces of the low-speed dynamic balance machine when installing the rotor. You can achieve a more satisfactory balance.
   Press cylinder:
   This is a kind of rotor whose unbalanced quantity is evenly distributed in the axial direction or distributed linearly. Because of the arrangement of the structure, the unbalance amount is evenly distributed along the entire length of the rotor. It is possible to select two planes and Balanced on a low-speed dynamic balancing machine, this speed can meet the desired balance.
So how to choose these two calibration surfaces is better, and it needs to be verified by some experiments. The analysis method is simple, only suitable for simple cases, such as: 1 single span, no cantilever, and quality And the rotor with uniform deflection and working speed much lower than the second-order critical speed, then theoretically, the better effective front position is at 22% span at both ends.