RU2314887C2 - Hollow section extruding method - Google Patents

Abstract

FIELD: plastic working of metals, namely tools and apparatus for hot extrusion of hollow sections including tubes.

SUBSTANCE: apparatus for pressing hollow sections has container, ram, needle and die. Needle is provided with centering plug whose outer surface engages with working walls of die. Said plug is made of low-carbon steel.

EFFECT: lowered wall thickness difference of sections, less loss of yield, reduced cost for making centering plug for multiple use.

2 cl, 3 dwg

Description

The invention relates to the field of metal forming, and in particular to a tool for hot pressing hollow profiles, including pipes.

Known devices for pressing hollow profiles and pipes containing a container, a stamp, a matrix with a centering sleeve in contact with the workpiece and the needle (AS No. 252272, class B21C 25/00, publ. 1968, paragraph 2).

A disadvantage of the known devices is that due to uneven settlement during prepressing of the workpiece in the container, the needle is shifted, which causes the product to be different.

The closest analogue to the claimed invention is a device for pressing hollow profiles, which is equipped with an additional centering sleeve mounted on a needle and in contact with the workpiece (AS No. 252272, class B21C 25/00, publ. 1968) - prototype. In the known device, the centering bushings are made of a material of a deformable workpiece.

The disadvantage of the prototype is the one-time use of centering bushings, i.e. on one product. The consumption of suitable metal increases as a result of its use for the manufacture of centering sleeves, as well as the additional costs necessary for the manufacture of centering sleeves. In addition, when pressing the workpiece in the container, a change in the shape (deformation) of the centering sleeves occurs, which leads to a displacement of the needle, which causes a difference in the product.

The problem to which this invention is directed, is to ensure reliable alignment of the needle relative to the axis of pressing by installing a centering plug, which allows to reduce the difference in finished products and increase yield.

The problem is solved in that in the device for pressing hollow profiles containing a container, a stamp, a needle with a centering element and a matrix in contact with the centering element, according to the invention, the centering element is made in the form of a tube, the outer surface of which contacts the internal working walls of the matrix while the cork is made of ordinary carbon steel and is reusable.

The invention is illustrated graphic materials.

Figure 1 presents the claimed tool for pressing hollow profiles, a longitudinal section;

Figure 2 and 3 shows the position of the centering plug 5 after the end of extrusion of the workpiece in the container (figure 2) and at the time of pressing the product (figure 3).

The device contains a container 1 with a matrix 6, in the cavity of which a press stamp 2 with a press washer 3 and a needle 4 is located, on the working part of which a centering plug 5 is placed. The plug 5 with its outer surface is in contact with the working walls (inner surface) of the matrix 6.

When unpressing the workpiece 7 (Fig. 1) in the container 1, the needle 4 is rigidly fixed at one end in the hole of the press washer 3. The working end of the needle 4 through the centering plug 5 enters the point of the matrix 6, which allows unpressing the workpiece 7 in the container 1, not disturbing needle alignment 4.

The proposed device was tested when pressing pipes with dimensions of ⌀75 × 12.5 mm and ⌀75 × 10 mm from aluminum alloy САВ1 under industrial conditions of the forging shop. The resulting products met the requirements of TU.

Heated to a temperature of 500-520 ° C, a workpiece 7 with dimensions ⌀272 × ⌀104 × ⌀630 mm is put on a greased needle 4, on which a press washer 3 and a centering plug 5 made of mild steel St3 were previously installed. During the piercing system, the needle 4 is fed forward and the centering plug 5 is installed in the hole of the die 6. Then, the workpiece 7 is pressed out in the container 1 and the pipe is pressed. The centering plug 5 is removed from the needle 4 and pushed out of the hole of the matrix 6 by a moving tube during the pressing process. After pressing, the centering plug is manually separated from the finished pipe and reused when pressing the next pipe, etc.

When pressing the workpiece 7 in the container 1, the needle 4 is rigidly fixed at one end in the hole of the press washer 3, the other end through the central plug 5 in the hole of the matrix 6, which allows you to press the workpiece 7 in the container 1, without disturbing the alignment of the needle 4, the axes of the holes of the matrix 6 and the container 1 relative to the axis of pressing.

The use of the proposed device for pressing hollow profiles in comparison with the prototype allows to reduce the difference in the extruded profiles and to increase the yield due to the use of a centering plug on the working end of the needle, which provides rigid fixation of the needle when pressing the workpiece in the container. In addition, the cost of manufacturing a centering plug is reduced when it can be reused.

Claims (2)

1. A device for pressing hollow profiles containing a container, a stamp, a needle with a centering element and a matrix in contact with the centering element, characterized in that the centering element is made in the form of a tube, the outer surface of which is in contact with the internal working walls of the matrix, while the tube is made with the possibility of reusable use. 2. The device according to claim 1, characterized in that the centering plug is made of mild steel.

Images