Experiences in Using Ultrasonic Testing of Bearing Steel for Demanding Applications

Abstract

The demands on modern machine parts, i.e., bearings, are increasing constantly. To ensure that highly clean steel is used, a number of different test methods are commonly used. In the field of test methods the ultrasonic immersion testing has reached a dominant position. This paper will give a short comparison of the ASTM E 588-03 and the SEP 1927 standards and will point out some experiences the authors have made using ultrasonic testing as a tool to increase steel cleanliness and using ultrasonic testing and blue fracture testing as complementary test methods. To be able to use ultrasonic testing as a powerful tool, a number of side aspects like the geometry of the test piece, the structure of it, or the frequency of the used ultrasonic-probe are important. This will be demonstrated by showing results from testing and incoming inspection.