Simple diagnosis method of vibration in gear machining

Simple diagnosis method of vibration in gear machining

The purpose of simple diagnosis during gear machining is to quickly judge whether the gear is in normal working condition, further accurately diagnose and analyze the gear in abnormal working condition or take other measures. Of course, in many cases, some obvious faults can also be diagnosed based on simple analysis of vibration.

Simple diagnosis of gears includes noise diagnosis, vibration level diagnosis and shock pulse (SPM) vibration level diagnosis, which are often used for diagnosis.

Vibration level diagnosis method is a diagnosis method that uses the vibration intensity of the gear to determine whether the gear is in normal working condition. According to different judgment indicators and standards, it can be divided into ^ value judgment method and relative value judgment method.

1. ^ value determination method

^The value determination method is to use the amplitude value measured at the same measuring point on the gearbox as an indicator to evaluate the operation status directly.

Gear status identification must be based on different gear boxes and different use requirements.

The main basis for formulating the gear ^ value standard is as follows:

1) Theoretical study of abnormal vibration;

(2) Analyze the vibration phenomenon according to the experiment;

(3) Statistical evaluation of measured data;

(4) Refer to relevant domestic and foreign standards.

In fact, there is no ^ value judgment standard applicable to all gears. When the size and type of gears are different, the judgment criteria are naturally different.

When judging the broadband vibration according to the measured parameters, the standard value must change according to the frequency. If the frequency is lower than 1kHz, the vibration is determined according to the speed; The frequency is higher than 1kHz, and the vibration is determined according to the acceleration. The actual standard shall be determined according to the specific situation.

2. Phase time value determination method

In practical application, for gears that have not yet formulated the ^ value judgment standard, we can make full use of the field measurement data to carry out the average statistics and formulate the appropriate relative judgment standard, which is called the relative value judgment method.

The relative judgment standard requires that the amplitude measured at the same measuring point of the gearbox at different times should be compared with the amplitude under normal conditions. When the measured value reaches a certain degree compared with the normal value, it should be judged as a certain state. For example, when the relative value judgment standard stipulates that the actual value reaches 1.6~2 times of the normal value, it should be noted that when it reaches 2.56~4 times, it should indicate danger. As to whether the specific use is classified by 1.6 times or 2 times, it depends on the use requirements of the gearbox. Rough equipment (such as mining machinery) is generally classified with higher multiples.