# Detection method for contact stress distribution of tapered roller bearings

## TL;DR

This paper introduces a new method to detect contact stress distribution in tapered roller bearings used in high-speed train axle boxes to improve safety and reliability.

## Contribution

A novel detection method using digital speckle correlation and machine vision for contact stress analysis in tapered roller bearings is proposed.

## Key findings

- Contact stress data from new and worn bearings under different lubrication conditions were collected and normalized.
- Normal and tangential stress distributions were obtained through data fitting and geometric relationships.
- The method provides a basis for evaluating bearing modifications and guiding bearing design.

## Abstract

The axle box of high-speed train adopts double row tapered roller bearings as transmission parts, and the reliability of bearings directly affects the safety of train operation. Tapered roller bearings can withstand axial and radial loads, their service life being closely related to the distribution of contact stress. The test object is the axle box bearing of high-speed train. According to bearing’s structural characteristics, based on the digital speckle correlation method (DSCM) and machine vision, the contact stress distribution detection devices for rollers and complete sets of bearings are developed respectively and an effective detection method is proposed. The contact stress data of the bearing which has reached the service life and the new bearing under the condition of no lubrication and grease lubrication are collected and normalized. Through the geometric relationship, based on the measured data of the selected detection points, the normal and tangential contact stress distribution of the roller and raceway under different contact conditions is obtained by data fitting. The test can be used as an evaluation basis for the effectiveness of bearing modification and provide reference for bearing design.