Nkk Corporation

Shuji Kaneto

Shoji Yoshikawa

Tsutomu Kawamura

Mitsuaki Uesugi

Akira Kazama

Takahiko Oshige

Masaichi Inomata

Masahiro Iwabuchi

Shinichi Tomonaga

Hajime Tanaka

Shigemi Fukuda

Osamu Uehara

Shuichi Harada

Yasuo Kushida

Tsuneo Suyama

Hiroyuki Sugiura

Naoki Matsui

Masayuki Yamazaki

Shigeru Moriyama

Takami Kubo

Shuichi Iwato

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.

A method for cold rolling a strip is wherein brushing roll are provided to both the work rolls and the back up rolls of the temper mill, to remove particles from the surface of the rolls of the mill and suction ducts adjacent to the brushing rolls transport the foreign objects out of the mill system. The sucking speed at the duct is at least 5 m/sec., and preferably 8 m/sec. The length of the bristle is from 15 to 60 mm, the diameter thereof being from 0.15 mm to 1.0 mm, and the material thereof is selected from a group of nylon, propyrene, or a the mixture thereof. The density of the bristle with respect to the peripheral surface area of the brushing rolls for the work roll is from 55 to 85% by area. Abrasive grains with a grain size of #300 to #1200 are incorporated in the brush of said brushing roll which enhance the brushing ability. The material of the abrasive grain includes at least one selected from a group of alumina, titania, and silicate, and the volume percentage of the grain with respect to the volume of the brush is from 5 to 30% in volume.

Cold rolling method using cleaning brushes for at least the back up rolls

Growing community of inventors

Hiroshima, Japan

Shuji Kaneto