The ultrasonic weld testing in ERW tube mills has been common practice for over 40 years, with a product being tested for defects and flash condition both on the mill (on-line) and on the finishing floor (off-line). Over the years ultrasonic systems have improved in performance, and today's PC-based systems provide unambiguous results with simple set-ups and include data storage capability. The ultrasonic method is ideal for testing ERW tube, as signal to noise ratios are excellent (very few false indications) and sensitivity is unaffected by wall thickness (ID and OD defects are equally discernible). Unfortunately, although the method is ideal, the application is imperfect.
展开▼
