Sumitomo Metal Industries Limited recently introduced a state of the art tailored welded blank facility at SSC Kyushu Co Limited, a coil centre based in the Kyushu region that Sumitomo Metals operates in cooperation with Kanpoh Steel Co Limited, Sumitomo Corporation and Sumikin Bussan Corporation. The facility entered operation on October 1st 2009.
Tailored welded blanks are a technology used to manufacture automobile parts by welding steel sheets with varied thickness and strength and then by forming into a part by only one blanking. Compared to the conventional method, the TWB technology enables to achieve both vehicle collision safety and the reduction of body weight, and contributes to auto makers' development of environmentally friendly vehicles.
The TWB facility that recently entered operation at KSSC is a state of the art fibre laser system. As a result, there are now six TWB supply bases operated by Sumitomo Metals and Sumitomo Corporation, which represents the largest TWB supply capacity in Japan.
1. Sumitomo Metals' TWB technology
Sumitomo Metals has a long tradition of research into welding technologies. With regard to TWB technology as well, Sumitomo Metals was the first company in Japan to start joint research on CO2 laser welding with Toyota Motor Corporation from around 1980. At its Corporate Research & Development Laboratories, as well, Sumitomo Metals initiated research by introducing mash seam welding, plasma welding, and various kinds of laser welding machines. In 2000, Sumikin Plant Limited, a group company, started manufacturing and selling TWB production equipment, and so far it has supplied 15 machines to 11 companies.
2. KSSC's state of the art TWB equipment
Previously, the Sumitomo Metals Group's TWB facilities that had been introduced in Japan mainly comprised YAG laser welding systems, but the Company has now introduced its first fibre laser welding machine (oscillator: output of 4 kW, manufactured by IPG Photonics Corporation; production equipment: Sumikin Plant Limited.). The fibre laser welding machine is the latest type of laser welding machine that causes lasers to oscillate from optical fibres. As Sumitomo Metals introduced a fibre laser welding machine with the highest output in Japan (10 kW) at the Kashima Steel Works No. 2 Steel Sheet Plant in September 2007, the Company has built up expertise concerning actual equipment. Based on this expertise, Sumitomo Metals introduced a TWB facility for fibre laser welding with the aim of ensuring the stability of performance and quality in tandem with low running costs.
3. Sumitomo Metals' and Sumitomo Corporation's TWB supply system
In the steel sheet business, Sumitomo Metals has established coil centres at various locations in Japan and overseas, in cooperation with Sumitomo Corporation, and worked to ensure carefully tailored delivery services with the aim of being rated number one by customers. As TWB technology enables different types of steel sheets, such as high-tensile steel and ordinary steel, to be combined on a customized basis in terms of optimal materials and optimal locations, it fulfils demands for a reduction in the body weight of vehicles and greater collision safety for automobiles, the largest source of demand for the steel sheet.
