Nkk Corporation

Hajime Tanaka

Shoji Yoshikawa

Tsutomu Kawamura

Mitsuaki Uesugi

Akira Kazama

Takahiko Oshige

Masaichi Inomata

Masahiro Iwabuchi

Shinichi Tomonaga

Shuji Kaneto

Hiroyuki Sugiura

Tsuneo Suyama

Yasuo Kushida

Shuichi Harada

Osamu Uehara

Shigemi Fukuda

A defect marking device includes a flaw inspection device which has a plurality of light-receiving parts that identify reflected lights coming from an inspection plane of a metal strip under two or more of optical conditions different from each other; a signal processing section that judges the presence/absence of surface flaw on the inspection plane based on a combination of reflected light components identified under these optical conditions different from each other; and a marking device which applies marking that indicates information relating to the flaw on the surface of the metal strip.

Method for marking defect and device therefor

The defect marking method comprises the steps of: installing a surface defect tester to detect surface flaw and a marker device to apply marking at defect position, in a continuous processing line of steel sheet; detecting the surface flaw on the steel sheet using the surface defect tester; determining defect name, defect grade, defect length, and defect position in the width direction of the steel sheet, on the basis of thus detected flaw information, further identifying the defect in terms of harmful defect, injudgicable defect, and harmless defect; applying tracking of the defect position for each of the harmful defect and the injudgicable defect; and applying marking to the defect position. The defect marking device comprises a defect inspection means having plurality of light-receiving parts and a signal processing section, and a marking means.

Growing community of inventors

Fukuyama, Japan

Hajime Tanaka