SU1227307A1 - Method of pressing cup-shaped articles - Google Patents

Description

The invention relates to the field of metal forming, in particular, to the technology of forming cup-shaped parts.

The purpose of the invention is to increase the quality of the parts produced by ensuring that the blanks are centered during the entire process of their deformation. .

FIG. 1 shows a sequence of techniques for implementing the method; in fig. 2 is a diagram for calculating the height of the punch advance.

The method is carried out as follows.

Ejector 1 initially push up to the height -N RM

Then, the workpiece 2 with a diameter of .rj is freely placed in the matrix 3. The proposed installation scheme assumes that the workpiece in the matrix rests on the matrix with both the peripheral surface and the center of gravity on the ejector simultaneously, which allows the center to be strictly centered in the matrix. Then, the punch 4 is approached to the workpiece before it is touched and the simultaneous movement of the punch and ejector down, during which the product is formed, and the reliability of centering is significantly improved.

(The extrusion process is completed at the time of closing the punch and die along plane A. The parts are removed by pushing it 1 up, the pushing is pushed to a height H, which is determined based on the dimensions of the workpiece and die (Fig. 2). If radius matrix cavities (spherical surface of the matrix), and Tj is the loading radius, then the outcome from the proposed scheme,

R2, -r | (R «-H) g, -2E„ H + H2, whence

; H -2RH + r | 0,

2R ± V4R -4r2

H

L

five

0

five

0

five

0

five

0

In this case, only one solution is possible, when, then

In SKTB Tantalum, the proposed method was surveyed. The method was tested by stamping a hemisphere of 160 mm. In the matrix with the lower ejector stacked blanks of various configurations: flat, cylindrical, conical and processed in the form of a stamp engraving.

It was not possible to obtain parts without defects from cylindrical and flat blanks, i.e. on all stamped blanks there were festoons, unevenness in wall thickness, clamps, etc. defects. In addition, the installation of the workpiece in the stamp spent a large amount of time.

The hemispheres were stamped on a DB2432 press made of AMGB alloy. The outer diameter of the hemisphere was 160 mm, the wall thickness was 3-5 mm. When stamping from conical blanks, the installation time was significantly reduced, the quality of parts improved, but the CMM was sharply reduced and the need for pre-processing of blanks appeared.

When stamping parts from blanks processed in the form of a stamp engraving, stamping defects did not appear, however, the metal utilization rate sharply decreased and the labor intensity of manufacturing blanks for stamping sharply increased.

The same stamp was used to stamp parts from Plb cylindrical blanks, with their centering with the help of a lower ejector extended by a certain amount depending on the dimensions of the blank.

During stamping, the absence of stamping defects was found due to uneven deformation, an increase in the productivity of the process due to a reduction in the installation time in the stamp, while the centering of the workpiece is done spontaneously under the force of the body weight of the workpiece.

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Claims (1)

METHOD FOR STAMPING OF CUP PARTS in dies with a lower ejector by placing a cylindrical workpiece in the die cavity and applying a deforming force to it, characterized in that, in order to improve the quality of the parts obtained, when placing in the die cavity, the workpiece is installed on the ejector, the end of which is placed over the bottom surface of the matrix at a distance defined by the expression N where R _M is the radius of the cavity of the matrix, mm; g ₃ - the radius of the workpiece, mm