RU2279328C2 - Large-size rings forging method - Google Patents

Abstract

FIELD: forging processes and equipment, possibly manufacture of large-size rings and shells whose outer diameter exceeds spacing between columns of press.

SUBSTANCE: method comprises steps of upsetting, piercing and expanding on mandrel. After expanding, forged blank is subjected to radial upsetting by value no less than D - B where D -outer diameter of forging, B - inter-column spacing of press in direction normal to forging axis in order to form oval-shaped blank. Oval bank is tilted by 90° around its lengthwise axis and turned by 90° around vertical axis. Then forged blank is subjected to secondary radial upsetting by the same value for forming round blank.

EFFECT: possibility for making forged rings in standard equipment without using additional special attachments.

5 dwg, 1 ex

Description

The invention relates to forge production and can be used for the manufacture of large-sized rings and shells, the outer diameter of which exceeds the annular distance of the press.

A known method of forging rings, including the operation of extrapress rolling to achieve a forging diameter exceeding the annular distance of the press (AS USSR No. 1199407, B 21 J 13/00). The disadvantage of this forging method is the need to manufacture a special device for its implementation.

Closest to the claimed is a method of forging rings, including draft, firmware, and rolling on a mandrel (AS USSR No. 375125, 21 K 1/38), selected as a prototype. The disadvantage of this method is that it does not allow to produce rings with a diameter greater than the annular distance of the press, since it is impossible to extract such a ring from the press space along the feed direction, and for the transverse extraction of the forging, special devices are required.

The objective of the present invention is the provision of the possibility of manufacturing forgings of rings with an outer diameter exceeding the annular distance of the press, on conventional forging equipment, without the manufacture of additional special devices.

The problem is solved due to the fact that in the proposed method, after the rolling operation to the forging size, the forgings are given an oval shape by radial upsetting. Radial draft is made so that the smaller axis of the oval does not exceed the annular spacing. Then, after tilting 90 ° around the horizontal axis of symmetry, the forging can be removed from the prepress space. Then, the oval forgings are turned around the vertical axis by 90 °, and repeated round radial draft of the same size is given to it round. Repeated radial draft is made in the plane of the largest axis of the oval.

The invention is illustrated by drawings:

figure 1 - the operation of rolling the ring on the mandrel to forging sizes exceeding the diameter of the annular distance of the press, where 1 is the mandrel, 2 is the forging ring, 3 is the rolling hammer, 4 is the press column, 5 is the press table,

figure 2 - arrangement of the ring after rolling in the annular space of the press,

figure 3 - the operation of radial upset to give the forging an oval shape,

figure 4 - the operation of the tilting 90 ° around the horizontal axis of symmetry,

figure 5 - the operation of re-radial upset, after a rotation of 90 ° around the vertical axis.

The method is implemented as follows. The ingot is precipitated, stitched and rolled on mandrel 1 until a forging 2 with a diameter D> B is obtained, where B is the distance between the columns of the press. Then brisk 3 produce a radial draft compression, exceeding D-In. Thereby, an oval-shaped forging is obtained, the transverse dimension of which in the narrowest part (along the small axis of symmetry of the cross section) is less than the annular distance. Next, the forging is turned over 90 ° around the horizontal axis of symmetry. The forging assumes a position in which the major axis of symmetry of the cross section becomes vertical. Then the forging is turned around this axis by 90 ° and a second radial draft is made by the same amount. In this case, the forging again takes a round shape, and its position under the press makes it easy to remove.

Example. The method was implemented on a press with a force of 120 MN, in which the annular spacing B = 5650 mm. An annular billet made of 15Kh2NMFA steel of the following sizes was preliminarily drafted, pierced, and rolled out on a mandrel: the outer diameter was 4800 mm, the inner diameter was 3200 mm, the height was 1600 mm, and the mass was 126 tons. Then, the workpiece was rolled out on a mandrel to an outer diameter of D = 5700, i.e. to a diameter exceeding the distance between the columns. Then, a 180 mm radial compression was carried out, while the workpiece took an oval shape, the small (vertical) axis of which became 5520 mm. Using a manipulator and a mandrel, the forgings were scanned 90 ° around the longitudinal axis of symmetry, after which it took a position in which the workpiece width 5520 mm became less than the distance between the press columns, which allowed it to be removed from the press. Then, using a crane, the forging was turned 90 ° around the vertical axis and again, using a table, it was filed under the press. Repeated radial compression on 180 mm forgings gave a round shape. Final dimensions: outer diameter 5700 mm, inner diameter 4530 mm, height 1670 mm.

Claims (1)

A method of forging large rings, including upsetting, piercing and rolling on a mandrel, characterized in that after rolling, the forgings are oval in shape by radial upsetting by compression, not less than DB, where D is the outer diameter of the forging, B is the annular distance of the press in the direction perpendicular to the axis of the forgings, then the forgings are turned 90 ° around its longitudinal axis, turned 90 ° around the vertical axis and repeated radial upsetting is made by the same amount, giving the forgings a round shape.

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