Automatic nondestructive roll defect inspection system

A computer-based nondestructive testing system for automatically inspecting roll surface conditions of a rolling mill roll rotatable in a test fixture and operable with a carriage movable substantially parallel and lengthwise of the test roll longitudinal axis, said system comprising:

• (a) nondestructive test probe means mounted on the movable carriage for generating at least one roll surface anomoly test signal;
• (b) means for automatically spacing the test probe means (a) from the roll surface by a gap having a fluid therein;
• (c) carriage movement sensor means on the carriage for generating a test probe means position signal relative to the distance along the roll length the test probe means has been carried by the movable carriage;
• (d) roll rotation sensor means in the rotatable test fixture for generating a roll circumference signal;
• (e) nondestructive test instrument means for processing at least one roll surface anomaly test signal from test probe means to produce an amplitude-variable roll surface defect signal;
• and
• (f) computer means for processing the amplitude-variable roll surface defect signal of (e), the test probe means position signal of (c) and the roll circumference signal of (d) comprising:
• (i) means for (1) converting the amplitude-variable roll surface defect signal into digital form, (2) detecting a digital defect signal peak and (3) allocating the digital defect signal peak into one of several preset levels in a memory device;
• (ii) means for (1) converting the test probe means position signal into digital form and (2) storing the digital position signal in the memory device of (f)(i)(3);
• (iii) means for (1) converting the roll circumference signal into digital form, and (2) storing the digital roll circumference signal in the memory device of (f)(i)(3);
• and
• (iv) means for coordinating the defect signal, test probe position signal and roll circumference signal for each inch of length of test roll surface scanned.