Kawasaki Steel Corporation

Jfe Steel Corporation

Akira Torao

Toshifumi Kodama

Takatoshi Okabe

Taira Suzuki

Yasumasa Tekemura

Yuichiro Asano

Motoji Shiozumi

Takayuki Yanagimoto

Hideo Abe

Ikuo Yarita

Kusuo Furukawa

Hajime Takada

Hiroaki Sasaki

Atsushi Momose

Takashi Kusaba

Susumu Moriya

Kunio Takahashi

Yoshihisa Kono

To precisely measure bead cutting shapes of electric resistance welded pipes without being affected by difference in luminance level between cut and uncut portions in optical cutting images, an image is obtained by overlaying an optical cutting image with the optical cutting image subjected to thinning processing. A profile of the welded pipe is approximated with a quadratic function and a region containing the bead apex coordinates is identified as the bead. Shape data of the pipe surface at the portion corresponding to the bead portion is obtained from the preset left and right boundaries of the bead portion and the apex position of the separately-calculated bead portion, and bead width, height, slope angle, and unevenness at the left and right boundaries between the bead portion and base pipe portion, are each calculated, based on the left and right bead shape approximation functions and base pipe shape approximation function.

Measurement method and device for bead cutting shape in electric resistance welded pipes

Method and instrument for measuring bead cutting shape of electric welded tube

A method and apparatus for ultrasonic flaw detection of line focus type suitable for detection of flaws in nonmetallic materials included in an object. Ultrasonic transmitter and receiver elements of line focus type are opposed at a distance (L) with an object under test placed between them, and a maximum ultrasonic echo is obtained at a distance L expressed by: L &equals;0.75(FT&plus;FR)&minus;&lcub;(CS/CW)&minus;1&rcub;t where FT (mm) is the focal length in the medium of the ultrasonic transmitter element of line focus type, FR (mm) is the focal length in the medium of the ultrasonic receiver element line focus type, CS (m/sec) is the speed of ultrasound in an object under test, CW (m/sec) is the speed of ultrasound in the medium, and t (mm) is the thickness of the object under test.

Ultrasonic flaw detection method and instrument therefor

The present invention relates to a method for detecting chattering of a cold rolling mill rapidly and accurately, which occurs during cold rolling of a steel strips. The occurrence of the chattering is detected by a plurality of acoustic parameters derived from a sound measured in the vicinity of the cold rolling mill during the rolling. The acoustic parameters are the frequency range characteristic of the occurrence of the chattering, the acoustic intensities in the frequency bands which are n-th harmonics, the peak frequency of the acoustic frequency component distribution, the resonance factor, the peak intensity, and the like. A plurality of parameters may be provided by measuring and calculating the same parameter with different timing.

Method and apparatus for detecting chattering in cold rolling mill

A work roll has a regularly and geometrically patterned uneven dulled section on the roll surface. Eavh uneven dulled section is composed of a crest and concavity and is of crater-like configuration. In order to obtain good performance in temper rolling, the crest is in a form of an annular ring extending around the edge of the concavity. According to the invention, pattern of arrangement of the uneven dulled sections is determined in relation to the diameter of the ring-shaped crests of the uneven dulled section so as to obtain optimum performance in producing good quality, exhibiting substantially high image clarify as coated by paint, enamel or so forth.

Work roll with dulled surface having geometrically patterned uneven

A seam locating system includes a laser beam scanning means for scanning a laser beam through a plurality of circumferentially aligned scanning points. The system includes means for forming a pattern image of reflected laser beam at each scanning points and means for forming a single-frame video image of the pattern image for each scanning point. A video signal processing circuit selects one or more scanning lines suitable for locating irregularities in the angle of reflection of the laser beam, for locating the scanning line in each frame with the maximum width over which the luminosity of the video signal is higher than a given threshold, for deriving a threshold value to be compared with the maximum width of each frame and for deriving the center position of the seam based on the comparison of the maximum width of each frame and the threshold value and the address of each frame, which address is indicative of the circumferential position of the corresponding scanning point. The seam locating system set forth above is not influenced by scale or the like which reflect the laser beam irregularly but with high luminosity by suitably selecting the scanning lines in each frame of video data. The seam locating system may further include means for feedback controlling the laser beam scanning means relative to the derived center position of the welded seam. Furthermore, the seam locating system according to the invention is applicable to seam-welded pipe annealing for automatically positioning the anneal device over the seam or for flaw detection in the welded seam.

Method and system for locating and inspecting seam weld in metal

In one aspect of the invention, the sample surface is wetted with an aqueous solution of a fluorescent dye followed by rinses with water to remove an excessive amount of the dye so that the background fluorescence emission can be minimized to increase the efficiency of fingerprint detection. In another aspect, the fluorescent dye or a reagent to produce fluorescent substance is deposited on the sample surface by attaching a gelatin film impregnated with a solution thereof followed by peeling. In a further different aspect, a powdery fluorescent dye is deposited on to the sample surface followed by spraying of water after removing an excessive amount of the powdery dye so that the background fluorescence can be minimized. The invention also provides an apparatus for the fingerprint detection by the laser beam excitation of fluorescence, which is compact and portable as being composed of an ingenious combination of several units into an integral system.

Method for detecting fingerprints using a laser and an apparatus therefor

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Chiba, Japan

Akira Torao