RU2405640C2 - Method of biller piercing and rolling-out - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming, namely to producing billets at piercing mill. Billet is pulled on mandrel by revolving rolls. In pulling on mandrel, the billet is pierced and rolls roll it out. When billet tail part reaches the rolls, "A" gap is formed between the rolls and billet since biller tail part diametre is smaller than billet OD after rolling-out. Rolls disengage from the billet, but mandrel does not. In this position the billet is easily removed from the rolls. Now, it is easily removed from the mandrel in the form of cup.

EFFECT: lower labour input and higher efficiency.

2 dwg

Description

The invention relates to the processing of metals by pressure, and in particular to the production of blanks on a piercing mill.

A known method of producing blanks on a piercing mill according to German patent No. 260425, class. 7a 19/02, 1913, taken by us as a prototype. The method consists in pulling the workpiece onto the mandrel using rolls and the processing process continues until the mandrel leaves the workpiece. To obtain blanks in the form of a glass, it is necessary to stop the processing process before the mandrel leaves the blank, and then take the rolls away, which is a laborious process. When processing the next workpiece, the rolls must be returned to their original position (set to a certain size). Moving the rolls requires a significant additional time, which increases the complexity and adversely affects the performance of this operation when receiving blanks in the form of a glass.

The problem to which the invention is directed is to reduce the complexity and increase the productivity of the operation when receiving blanks in the form of a glass on the piercing mill.

This problem is solved using the method of flashing blanks and their drawing, which consists in flashing a mandrel of a cylindrical blank with simultaneous drawing by rolls, where the flashing and drawing out process is stopped before the mandrel leaves the blank due to its final part made with a diameter smaller than the diameter obtained after drawing .

The application of this method, where the termination of processing is carried out before the mandrel leaves the workpiece due to the final part of the workpiece made with a diameter smaller than the diameter obtained after drawing, in order to obtain blanks in the form of a cup on the piercing mill and made it possible not to take the rolls and free the workpiece due to diameter differences of the final part of the workpiece. The proposed method allows to reduce the complexity and increase the productivity of the operation.

The method is illustrated in the drawing, where in Fig.1 shows the moment of the process of flashing and drawing, in Fig.2 - the final position of the rolls after flashing and drawing.

The workpiece 1 (Fig. 1) is pulled by the rotation of the rolls 2 onto the mandrel 3. In the process of pulling the mandrel 3, the workpiece 1 is flashed, while the rolls 2 are drawn out. Upon reaching the workpiece 1 (figure 2) of its final part 4 of the rolls 2, a gap "A" is formed between the workpiece 1 and the rolls 2, because the final part 4 of the workpiece 1 is made with a diameter smaller than the outer diameter of the workpiece 1 obtained after drawing. The coupling of the rolls 2 with the workpiece 1 is stopped, while the mandrel 3 does not come out of the workpiece 1. In this position, the workpiece 1 is freed from the rolls 2. The workpiece 1 in the form of a cup is freely removed from the mandrel 3.

Claims (1)

A method of flashing and drawing a cylindrical workpiece, including flashing a mandrel of a cylindrical workpiece while drawing it with rolls, characterized in that the final part of the workpiece is made with a diameter smaller than the diameter of the workpiece obtained after drawing, while the process of flashing and drawing is stopped before the mandrel leaves the workpiece.

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