CS239008B1 - A method for forging rotary forgings with a larger aperture, in particular a ring wheel from rings - Google Patents

Abstract

The method of forging rotary forgings with a larger hole according to the invention is carried out in a closed die with an internal compensation cavity. The essence of the invention lies in the fact that a forging with an internal protrusion is forged from a β annular-shaped blank. In a further operation, the internal protrusion is removed by cutting out the hole of the finished forging.

Description

The invention relates to a method of forging rotary forgings with a larger opening, in particular ring wheels of rings on vertical crank presses, of which the finished forging has at least one end face having a contoured shape. The cross-section of the rings is generally rectangular.

The known method of forging the disc wheels and the parts similar to them of the rings is carried out in an open die with an internal relief cavity. In the final phase of this forging, the material flows into both the outer and inner discharge cavities.

The outer and inner burrs are then removed in a progressive or composite trimmer. A disadvantage of this method of forging is the large loss of material and hence the energy required to heat the starting material. The weight of the ring must be considered when determining the weight of the ring.

The above-mentioned disadvantages are overcome by a method of forging rotary forgings with a larger bore, in particular ring wheels from rings. The method is performed in a closed die with an internal compensating cavity and wherein the forging operation is followed by a shearing operation. The invention is based on the forging of an annular blank with an internal forging.

In another operation, the inner burr is removed by cutting it from the hole of the finished forging. The blank before the forging has a centering surface adjusted to the exact diameter and shape.

The advantages of the method of forging rotary forgings with a larger bore according to the invention consist in less material and energy loss in a simple tool for punching the internal burr which can be transferred from a trimming press to a forging press. Another advantage is the prolongation of the life of the die resulting from the smaller one

- 2 239 008 displacement of material during forging and from less forging force.

FIG. 1 shows the individual operations of the forging method according to the invention, in which FIG. 1 shows a ring obtained from small-series or medium-series production; FIG. 2 shows a semi-finished product with a modified centering surface; 3 shows an internal forging forging and FIG. 4 a finished internal forging forging.

In small series production, the ring 1 is obtained by free forging on the mandrel in cash or with subsequent rolling. In medium and large series production, the ring 1 is obtained by die forging followed by rolling or dividing thick-walled tubes. The diameters of the ring 1 may be adjusted, i.e. increased or decreased, prior to forging. By adjusting the ring 1, the shape is refined and the desired diameter is obtained for which the ring 1 is sprayed in the die during manual operation. The diameters of the ring 1 indirectly indicating its height are selected so that only when the forging is sufficiently shaped. For the method according to the invention, the ring must be provided in a blank 2 _t having a centering surface adapted to both the exact diameter and the exact shape. The method of the invention is carried out in a closed die with an internal compensating cavity. In a first operation of the annular blank, the forging 6 is forged with an internal fin

In the second operation, the inner bead 8 is cut from the hole of the finished forging 4, thereby obtaining the finished forging 4 of the disk wheel.

The fitting method according to the invention is used in the manufacture of disc and crown wheels, inner rings of spherical thrust bearings and other larger-bore parts which cannot be finished without roll-forming and whose direct fitting with a membrane would greatly reduce material utilization.

Claims (1)

Method for forging rotary forgings with a larger bore, in particular ring rings, performed in a closed die with an internal compensating cavity and wherein the forging operation is followed by a shearing operation, characterized in that a forging (3) is forged from the annular blank (2). with an internal projection (5), which is removed by cutting it from the hole of the finished forging (4);