Turbochargers are necessary elements of car engine, and therefore require a precise balancing process of a rotor. There are 2 stages:
- balancing of compressor wheel, spacers and seal elements, as well as nuts
- balancing in the own bearings in the central body
Special balancing machines are used to balance impellers of turbochargers. In the first phase it is advisable to employ a horizontal balancing machines, which main task is to power the balanced element and measure and two-dimensional measurement of vibrations. It must have an algorithm allowing to easily determine mas korygujących.
Balancing in the first phase is based on removal of the material accumulating on the inner surfaces of turbine wheel and compressor by polishing. It is done until the allowable amount of material is reached.
Even if vibrations reach too high level after the turbine core is installed, it is best not to dismount the core again and balance the rotor in the own bearings in the central body.
As a rule, impellers rotate taking advantage of the stream of air and should be stable. Their value should amount to several thousands revolutions per minute. It is essential not to forget about a proper lubrication of sliding bearings. Good quality turbochargers do not need a usage of rotor marks They may cause interference during measurement. Therefore balancing machines are equipped with laser sensors.
What is important, each balancing machine operates in a slightly different way, even if manufactured by the same producer, and therefore the same rotor with the same level of balance (unbalance) may reach different measurement systems depending on the machine. The calibration of machines for a particular rotor is so important. As a result rotor tested on different machines should achieve a very close state of unbalance. Calibration means a proper adaptation of measurement system to the particular type of rotor. These days balancing machines for turbochargers are so modern that calibration to the particular rotor takes just a couple of minutes.