Jfe Steel Corporation

Kazutoshi Ishikawa

Tatsuro Katsumura

Hiroyuki Fukuda

Yasuhide Ishiguro

Masatoshi Aratani

Yukio Miyata

Ryoji Matsui

Noritsugu Itakura

Tomonori Kondou

Tetsu Nakahashi

Seiichiro Nambu

Koji Sugano

Provided is an electric-resistance-welded steel pipe or tube for a hollow stabilizer where the formation of not only a ferrite decarburized layer but also a total decarburization layer can be suppressed even when heat treatment is performed in the air. The electric-resistance-welded steel pipe or tube for a hollow stabilizer has a predetermined chemical composition, and the depths of total decarburized layers on an inner surface and on an outer surface are 100 μm or less.

Electric-resistance-welded steel pipe or tube for hollow stabilizer

Through a tube expanding processing simulation, a workpiece shape in a state where a tip of a workpiecehas advanced by 1.0 m or more after passing through a shoulder portionof a toolis evaluated. A hollow piece shape and a tool shape such that the external diameter is within &#xb1;1% of the target, the thickness is within &#xb1;7.5% of the target, and the internal gap between the hollow piece and the tool is 1.0 mm or less are obtained by repeated calculation, and thereby actual tube expanding manufacturing conditions are determined.

Tube expanding method for manufacturing metal tube

A method for manufacturing a heavy wall steel pipe includes a cooling step in which a steel pipe, with a wall thickness of &#xbd; inch or more, that has been heated to the gamma range is dipped in water while supporting and rotating the steel pipe about the axis of pipe, an axial stream which is a water flow in the direction of axis of pipe is applied to the inside surface of the steel pipe under rotation in the water, and an impinging stream which is a water flow impinging on the outer surface of the pipe is applied to the outer surface of the steel pipe under rotation in the water.

Method for manufacturing heavy wall steel pipe

Growing community of inventors

Aichi, Japan

Kazutoshi Ishikawa