SU1281954A1 - Method of predicting service life of bearing cages - Google Patents

Abstract

The invention relates to a testing technique, namely to testing rolling bearings, preferably high-speed bearing supports. The purpose of the invention is to improve the accuracy of control and prediction of the service life of bearing cages, as well as to expand the technological capabilities of the company. During the test, the amplitude of the harmonic component with the frequency of rotation of the separator is measured. The service life of the separator is determined by the measured amplitude and the ratio of the frequencies of rotation of the separator and the podspnik ring. This makes it possible to take into account the dynamic imbalance of sepa;

Description

I

The invention relates to the bearing industry and can be advantageously used to predict the service life of bearing cages.

The purpose of the invention is to improve the accuracy of prediction of the service life of bearing cages by taking into account. the dynamic unbalance of the separator.

The method is carried out as follows.

The ball bearing with the test cage is driven into rotation. The rotational speeds of the bearing ring separator are measured, as well as the amplitude of oscillation of the separator at the rotational speed.

The service life of the separator is determined from the ratio of the frequencies and the measured amplitude of the separator and the bearing ring on the basis of experimental calibration graphs.

Example. Two separators were inspected - the operability was determined (the life expectancy was predicted) of 76-10D0904P2 ball bearings manufactured according to ETU-100 (SHC, P 37 mm, inner 20 mm, 0iiicip 5 mm, the number of balls; 10 pcs.).

During the test, a stand was used to measure the vibration of rolling bearings, a frequency meter, a frequency divider, a vibration analyzer, frequency sensors for the rotation of the separator and the inner ring of the bearing, and vibration sensors.

The permissible values of the ratio of the rotational speeds of the separator and the bearing ring, as well as the amplitude of the harmonic component with the rotational speed of the separator, were preliminarily determined by using different bearings with different characteristics for durability. The following values were obtained: the minimum allowable ratio of the frequencies of rotation of the separator and the bearing ring is 0.35, the maximum allowable value of the amplitude - vibration velocity for the ratio of frequencies of 0.35-3.2 mm / s.

At the same time, the limiting ratio of 0.35 characterizes the separator slippage of 15%, and the bearings, in which the defined characteristics exceeded the permissible values, were 25 times.

81954 2

collapsed, without reaching the required resource 1500 hours

In the study of two ball-bearing cages 76-1000904Р2, the internal bearing ring with a frequency of f 200 Hz was set to rotate. The bearing was loaded with a working axial and radial load. As a reference base signal, knock out the signal from the separator speed sensor, which through the divider (decreased 10 times, since there were 10 balls in the bearing) was applied to the vibration analyzer. Better hp

J5 The following analysis of the spectrum at the frequency of rotation of the separator. For the first bearing under study, the value of vibration velocity A 2.4 mm / s was obtained, and for the other - A 3.7 mm / s. With

20, this determined the ratio of the rotational speeds of the separator and the bearing ring, which were respectively 0.40 and 0.335.

Since the amplitude of the harmonic component — the vibration velocity of the second bearing — exceeds the maximum permissible value and the frequency ratio is less than the allowable value, it was concluded that the separator was unsuitable for operation in a product with a lifetime of T 1500 hours. The separator of the first bearing under study was found to be operational: operation.

35 The method allows to increase the accuracy of prediction of the service life of high speed ball bearings as a result of accurate determination of the service life of the separator.

40

Claims (1)

Invention Formula 45 A method for predicting the service life of bearing cages, which consists in measuring the rotational speeds of the separator and bearing rings, 50 by the fact that, in order to increase the forecasting accuracy by taking into account the dynamic unbalance of the separator, the amplitude of the harmonic component is additionally measured with  the frequency of rotation of the separator and the measured amplitude and ratio of the frequency of rotation of the separator and the bearing ring determine the service life of the separator.