Cold pilgrim rolling
AssigneeMannesmann Aktiengesellschaft
InventorsJosef Gerretz, Horst Stinnertz
Life of this patent
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Abstract
A method of making tubing includes cold pilgrim step rolling wherein particularly a frame moves back and fourth carrying tapering rolls which roll in alternating directions upon the stock to be rolled whereby in addition a cylindrical mandrel is provided as well as turning and advancing facilities for the tube or pipe to be made and with further utilization of a rotatably driven clamping and holding device downstream for extracting the tubes or pipes being made.
Claims8
In a method for cold pilgram step rolling using a reciprocating frame having tapered rolls journalled thereon, said rolls rolling alternatingly with respect to rolled stock, the method further including using essentially cylindrical mandrel upon which hollow stock is being rolled by said rolls and still further using a turning and advancing structure for the hollow stock to be rolled upstream from the rolls, the improvement of:
- providing for a relative speed between the mandrel and the rolled hollow stock, during the rolling of the stock to obtain a tube, and in relation to the tube thus being rolled, so that the mandrel can be retracted;
- and retracting the mandrel from the tube, during a last phase of rolling the tube.
Dependencies are inferred from the claim text.