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Products and solutions, 2004-03-29, 02:00 AM

Edelstahl Witten Krefeld: global partner to the tube industry

Edelstahl Witten Krefeld GmbH will be exhibiting at Tube for the first time in 2004. For more than 100 years the company has been producing specialty steel long products of tool and high-speed steels, stainless, acid- and heat-resistant steels as well as special structural and bearing steels. Tool steels are used for hot-work tools such as die-casting dies, forging dies, mandrel bars and aluminum extrusion dies. They also find application in plastics molds and cold-work tools.

Among the products being displayed by Edelstahl Witten Krefeld at Tube (hall 12, booth 12 A 21) will be mandrel bars made of hot-work steel for the production of seamless tubes. Mandrels are central to the production of such tubes. The mandrel is inserted into a pre-pierced steel billet and shapes the inside of the tube during the rolling process.

Of the approximately 60 million tons of steel tube produced around the world, some 25 percent are hot rolled seamless. Edelstahl Witten Krefeld supplies its large mandrel bars to almost all the world`s seamless tube producers and offers the widest range of sizes in Europe. Its modern rolling mill in Witten produces mandrel bars up to approximately 30 meters in length. The world`s largest forging machine, the RF 70, is also available for producing bars in diameters up to approximately 265 millimeters depending on length.

The mandrel bars are made from Thyrotherm hot-work steels from Edelstahl Witten Krefeld. These materials are alloyed with chromium, molybdenum and vanadium for high elevated-temperature strength and can withstand temperatures of more than 500 degrees Celsius depending on alloy content. Thyrotherm steels are available with mechanical strengths of more than 1,200 newtons per square millimeter. As well as versatile standard grades, the company also offers special Thyrotherm variants adapted for different seamless tube manufacturing methods and conditions.

Edelstahl Witten Krefeld supplies the mandrel bars either peeled or finish machined to customer specifications. On the ground version, diameters meet extremely close tolerances in the tenth of a millimeter range over the full length. Depending on bar type the ends are precision machined with tapers, tangs or internal threads. Finally the bars are given a scale or chromium coating to prevent them from sticking to the tube material during production.

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ThyssenKrupp Steel AG
Dietmar Stamm
Phone: +49 203 / 52 - 2 6267
Fax: +49 203 / 52 - 2 57 07

Bernd Overmaat
Phone: +49 203 / 52 - 4 51 85
Fax: +49 203 / 52 - 2 57 07

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