A dynamic balance detection method for multi-disc rotors based on rotating coordinate system

Abstract

The invention discloses a multi-wheel-disc rotor dynamic balancing test method based on a rotating coordinate system. The method includes calibrating an angular coordinate on a wheel disc, and arranging strain sensors on the cross section of shafts on both sides of the wheel disc of a rotor; respectively recording strain values of the wheel disc in the corresponding direction under different stress in two perpendicular direction, and respectively calibrating direction coefficients of the relationship between the strain and force in the two direction; starting a motor to provide a given balancing speed n, and measuring an average value of the strain in the two perpendicular direction of the cross section in the rotating coordinate system; calculating the magnitude of the unbalanced force on the wheel disc and the phase through the obtained average value of the strain and the direction coefficients in the two perpendicular direction, wherein the phase can be directly read out through the rotating coordinate system; obtaining the weight m weighted on the wheel disc and the phase theta through the obtained unbalanced force, the given balancing speed n and the given weighting radius r. The multi-wheel-disc rotor dynamic balancing test method based on the rotating coordinate system can be used for testing without a key phase sensor and data acquisition synchronization of measuring points, thereby greatly reducing the requirement on sampling rate of a data acquisition system.

Description

technical field [0001] The invention relates to the detection of rotating mechanical parts, in particular to a method for detecting the dynamic balance of a multi-disc rotor in a rotating coordinate system. Background technique [0002] Rotating machinery, such as steam turbines, generators, gas turbines, compressors, fans, pumps, etc., are key equipment in industries such as aviation, electric power, petrochemical, and metallurgy. Affected by factors such as rotor machining accuracy, assembly error, and thermal deformation, the center of mass of the rotating machinery parts does not coincide with the center of rotation, and an unbalanced excitation force will be generated in the rotating state, resulting in vibration of the unit and shortening the service life of the unit. Unbalanced faults are the most common vibration faults of various types of rotating machinery, accounting for more than 80% of all types of faults. It is of great engineering significance to improve the ...

AI Technical Summary

Problems solved by technology

This method is widely used in engineering, but it has the following disadvantages: (1) The influence coefficient needs to be obtained through experiments, and the unit needs to be started and stopped repeatedly, and the efficiency is low

This method has the following disadvantages: (1) the rotor is regarded as a rigid rotor, and the elastic deformation of the rotating shaft is not considered; (2) the unbalanced force is equivalent to two planes, and the weighted surface and the unbalanced surface are often not on the same plane; (3) It needs to be equipped with a special dynamic balancing machine, which has higher requirements for testing equipment

At this stage, the sampling frequency of wireless testers is limited, the highest is only 1KHz

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