In order to determine the size and position of the calibration mass of the rotor to be balanced, during on-site dynamic balancing calibration, the method of placing trial masses is used to temporarily change the mass distribution of the rotor, measure the changes in vibration amplitude and phase caused by this, and determine the size and placement position of the truly required calibration mass based on the effect of the trial masses.
Any point on the bearing periodically experiences centrifugal force generated by rotor imbalance at the same frequency as the rotational speed. So in the frequency spectrum of vibration signals, the imbalance is manifested in the increase of vibration signals at the rotational frequency.
Generally, a vibration sensor is installed on the rotor bearing housing to measure the vibration caused by imbalance. The vibration signal at the rotational frequency is proportional to the force generated by the unbalanced mass. In order to measure phase and rotational frequency, a speed sensor is also required. This instrument uses a laser photoelectric speed sensor, with the position of the reflective strip as the phase reference point of the vibration signal, to determine the unbalance angle of the rotor. In summary, the amplitude and phase of unbalanced vibration can be used to determine the balance correction torque and the correction angle relative to the position of the test weight center. After selecting the calibration radius, the size and placement position of the calibration mass can be calculated based on the calibration torque and angle.
Any point on the bearing periodically experiences centrifugal force generated by rotor imbalance at the same frequency as the rotational speed. So in the frequency spectrum of vibration signals, the imbalance is manifested in the increase of vibration signals at the rotational frequency.
Generally, a vibration sensor is installed on the rotor bearing housing to measure the vibration caused by imbalance. The vibration signal at the rotational frequency is proportional to the force generated by the unbalanced mass. In order to measure phase and rotational frequency, a speed sensor is also required. This instrument uses a laser photoelectric speed sensor, with the position of the reflective strip as the phase reference point of the vibration signal, to determine the unbalance angle of the rotor. In summary, the amplitude and phase of unbalanced vibration can be used to determine the balance correction torque and the correction angle relative to the position of the test weight center. After selecting the calibration radius, the size and placement position of the calibration mass can be calculated based on the calibration torque and angle.
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