SU144814A1 - Method for the production of pipes on a three-roll mill oblique rolling - Google Patents

Description

Known methods for the production of seamless pipes on three-roll mill rolling slanting.

The described invention also concerns a method for producing pipes in a three-roll oblique rolling mill and has the goal of creating a rigid end of the liner during rolling. This is achieved in that the sleeve is tapered, rolled with an air-cooled tapered mandrel having a variable or constant taper in length, and front and back tension are created to roll the pipe to uniformly deform the metal in the axial direction.

FIG. 1 and 2 depict the liner and the pipe rolling pattern.

After flashing, the sleeves / its ends are given a conical shape, which can be carried out, for example, on a horizontal forging machine or in another way, depending on the specific operating conditions of the production line. The wall thickness at the ends of the sleeve must be less than the wall thickness of the finished pipe. After this preparation, a liner is rolled / on a three-roll mill using a mandrel 2 which is hollow and cooled with water. The mandrel 2 has a conical outer surface with a constant or variable taper in length.

For uniform deformation of the metal with the help of appropriate devices, the pipe is subjected to front and rear tension, and at the moment the rear end of the sleeve approaches the rollers, the device creating the rear tension must be turned off.

By creating rigid ends on the liner during rolling, it is possible to produce more thin-walled tubes compared to known methods. The creation of an increased axial flow of the metal due to the tension of the liner in the axial direction reduces the possibility of the formation of ring fractures in the pipe walls, which improves the quality of the rolled products.

The application of the described method of producing seamless pipes on a three-roll oblique rolling mill allows the pipe to be manufactured to be expanded by rolling thin-walled pipes.

Subject invention

The method of producing pipes for a three-roll oblique rolling mill is distinguished by the fact that, in order to create a rigid end during rolling, the sleeve is tapered, rolling is performed with a water-cooled tapered mandrel having a variable or constant taper, and a rolled pipe create front and rear tension for uniform deformation of the metal in the axial direction.

2 522Ж: Ж2Ж2 Ж