Dyckerhoff & Widmann Aktiengesellschaft

Stahlwerk Annahuette Max Aicher Gmbh & Co. Kg

Stahlwerk Annahütte Max Aicher Gmbh & Co. Kg

Max Aicher Gmbh & Co. Kg

Max Aicher

Dieter Jungwirth

Dieter Russwurm

Hans-Wilhelm Klein

A formwork tie rod () which is provided with a thread on the end portions () has a conical plastic sheath () between the threaded portions () for removal from the hardened concrete. For form-fitting connection to the plastic sheath () the tie rod () is provided with projections between the threaded portions ().

Formwork tie rod having conical plastic sheath

To produce threaded steel tension members, steel is used with a C-content of 0.50 to 0.80%, preferably 0.75%, a Si-content of 0.20 to 0.50%, preferably 0.25%, and a Mn content of 0.30 to 0.80%, preferably 0.60%. Exiting from the rolling heat at the outlet side of the finishing stand after hot rolling, the tension member or rod is subjected to surface quenching by a cooling medium, preferably water, so that the steel in a rim zone R.sub.1 is transformed immediately and completely into martensite, while the heat content remaining in the core zone K.sub.1 does not effect a tempering of the martensite rim zone during the subsequent cooling beyond the range of the intermediate stage. Steel tension members of this type have a high ductility and toughness at a high yield limit and high strength, they are corrosion-resistant to a great degree and have a wear resistant surface which makes them particularly suitable for threaded tension rods in which the threads are produced either by a cold forming operation or hot rolled ribs.

Method for producing rolled steel products, particularly threaded steel

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Freilassing, Germany

Max Aicher