Process for the rolling of hallow ingots on a assel rolling mill
AssigneeMannesmann Aktiengesellschaft
InventorsJurgen Pietsch, Ingo Baade
Life of this patent
Estimating the term…
Abstract
The invention relates to a process for reducing the outside diameter and wall thickness by rolling a cylindrical hollow ingot the front part of which is fed into an Assel rolling mill, in which connection, in front of the Assel rolling mill as seen in the direction of feed, a device is provided for reducing the diameter and/or wall thickness of the rear end part of the hollow ingot threaded onto a mandrel rod. In this process, the prereduction rolls are slowly and continuously pressed against the ingot at a predetermined point near the end of the ingot to produce a conically reduced end portion.
Claims14
A method of reducing the outside diameter and wall thickness of a cylindrical hollow ingot having a front end, a back end and an outside diameter, the front end of which is to be fed into an Assel rolling mill, the method comprising:
- providing a plurality of prereduction rolls in advance of said Assel rolling mill, the outer surfaces of said rolls being oriented around said ingot in a circular pattern having a diameter;
- feeding said ingot at a constant speed through said circle of prereduction rolls;
- and
- reducing said diameter so as to advance said prereduction rolls against said ingot proximate said back end at a constant pressure over a desired length of said ingot as measured along the longitudinal axis of said ingot from said back end so as to produce a cone shaped region on said ingot, said desired length being approximately 1.0 to 1.25 times said outer diameter of said ingot.
Dependencies are inferred from the claim text.