In 1970, the Keihin Works of NKK, Kawasaki, Japan, installed an automatic ultrasonic testing system (based on the pulse reflection method with double crystal probes) on the finishing line of their 134 in. heavy plate mill. The system has a combination of four automatically controlled testers and is capable of testing a portion over a width of 2 in. on the periphery and over 25 percent at the center portion. Plates to be tested for interior defects were from 6 to a maximum of 19 mm thick, the range capable of being sheared on the line. Efforts were directed toward solving problems related to high-speed testing at elevated temperatures and flaw-distance dependence on testing sensitivity. The resulting system operates without precooling equipment with plate temperatures up to 200 C and at a speed of 40 m/min. Distance-amplitude correcting circuits in the receiving section permit proper evaluation of flaws, including surface flaws. Test information is fed back to the rolling and steelmaking operation by a computer, thus contributing to improved plate quality.

  • Corporate Authors:

    Association of Iron and Steel Engineers

    Empire Building
    Pittsburgh, PA  United States  15222
  • Authors:
    • Matsumara, Y
    • Katsuyuki, N
  • Publication Date: 1975-4

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 75-79
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00172609
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 29 1978 12:00AM