Detection of Cam Grinding Burns Using the Eddy Current Method

This paper develops an eddy current method for the detection of grinding burns on cams. Based on the eddy current testing method, a spiral scanning mechanism is developed so that a uniform spiral scan of the eddy current probe over the surface of the cam is realised. The eddy current signal from the scanning process is extracted and wavelet transform signal processing technology is adopted to achieve rapid detection of any grinding burns on the cam. The test results are compared with those from an acid pickling test and prove the feasibility and reliability of eddy current testing for the detection of grinding burns. The results also show that the eddy current testing method has a good ability to identify and judge the degree of grinding burn on the cam. The method can be applied in the detection of burns for various types of grinding products.