Flaking development analysis method and flaking development analysis device for raceway ring of rolling bearing

1. A flaking development analysis method for a raceway ring of a rolling bearing for predicting development of flaking of a raceway ring of a rolling bearing which is to be used in a rotation machine and includes inner and outer raceway rings and rolling elements between the two raceway rings, comprising the steps of:

acquiring presence or absence and a shape of flaking of the raceway ring by a flaking state acquisition unit;

calculating, based on at least the acquired shape of the flaked portion, a specification of the rolling bearing, and a working condition of the rolling bearing, a rolling element load acting on a rolling element when the rolling element passes through an exit portion of the flaked portion of the raceway ring taking a shape of the in-progress flaked portion into consideration;

calculating, based on the rolling element load at the exit portion of the flaked portion, a development speed of the flaking in which a shape of the in-progress flaked portion is taken into consideration; and

calculating a relationship between an elapsed time and a shape of the flaked portion based on the development speed of the flaking.

2. The flaking development analysis method for a raceway ring of a rolling bearing according to claim 1 , wherein

the shape of the flaked portion is a circumferential length of the flaked portion, and

the step of calculating the rolling element load at the exit portion of the flaked portion is given by calculating a balance of force corresponding to the circumferential length of the flaked portion.

3. The flaking development analysis method for a raceway ring of a rolling bearing according to claim 2 , wherein

the step of calculating the development speed of the flaking is given by a crack development speed in which fluctuation in stress at the exit portion of the flaked portion obtained by a finite element analysis using the rolling element load at the exit portion of the flaked portion is set to a stress intensity factor range.

4. The flaking development analysis method for a raceway ring of a rolling bearing according to claim 1 , further comprising:

a step of outputting, as a remaining lifetime, a remaining time until a shape of the flaked portion specified in advance is obtained.

5. A flaking development analysis device for a raceway ring of a rolling bearing for predicting development of flaking of a raceway ring of a rolling bearing which is to be used in a rotation machine and includes inner and outer raceway rings and rolling elements between the two raceway rings, comprising:

a flaking state acquisition unit configured to acquire presence or absence and a shape of flaking of the raceway ring; and

an arithmetic unit configured to:

calculate, based on at least the acquired shape of the flaked portion, a specification of the rolling bearing, and a working condition of the rolling bearing, a rolling element load acting on a rolling element when the rolling element passes through an exit portion of the flaked portion of the raceway ring taking a shape of the in-progress flaked portion into consideration,

calculate, based on the rolling element load at the exit portion of the flaked portion, a development speed of the flaking in which a shape of the in-progress flaked portion is taken into consideration, and

calculate a relationship between an elapsed time and a shape of the flaked portion based on the development speed of the flaking.

6. The flaking development analysis device for a raceway ring of a rolling bearing according to claim 5 , wherein

the relationship between the elapsed time and the shape of the flaked portion is stored in advance in a storage unit according to a specification of the rolling bearing.