SU852446A1 - Apparatus for extruding double-layer tibes from powder - Google Patents

Description

one

The invention relates to powder metallurgy, in particular, to devices for pressing two-layer tubes of powder.

A device for pressing two-layer pipes made of powder is known, including its matripe, a speck liner and actuator coaxially mounted therein. The device also contains a frame and a bunker, the liner is stepped, and the drive serves for vras, matrix. The process of obtaining double-layer pipes consists of sequentially performing the outer, and then the inner layer of the pipe using a step-like insert, installed with the possibility of mixing, along the axis of the matrix.

The disadvantages of this device are both the periodicity of the process of manufacturing the pipe as a whole, and the periodicity of manufacturing the pipe layers.

During the cycle, corresponding to the fabrication of the pipe, it is necessary to stop the insertion of the matrix twice, to turn the vibrator on and off twice, to fill the bumper twice and to release the powder from the powder, to move the liner twice. In addition, it is impossible to obtain different lengths of the pipe without replacing the elements of the device, since the length of the pipe is structurally related to the length of the die and the length of the steps of the liner.

The purpose of the acquisition is to increase the productivity of the process and ensure its

5 continuity.

This is achieved by the fact that the device for pressing two-layer pipes of ioroshka, including its matrix, coaxially mounted liner and actuator, is equipped with

10 with a variable inner diameter sleeve and an additional hollow screw with a nozzle in its lower part; the nozzle is made with a conical surface at the level of the expanding part of the sleeve; FIG. 1 presents the proposed

20 device incision; in fig. 2-section A-A in FIG. one.

The liner 1 and the additional screw 2 are arranged soospo, so that the liner 1 is located in the inner cavity of the screw 2.

25 The walls of the screws are made as screw surfaces of the opposite direction.

Inside the liner 1 there is a stationary stepped rod 3, fixed 30 in the upper base 4,

The rod 3 in the lower part has a conical and cylindrical steps.

In the upper part of the liner 1 there is a gear 5, which rotates from two opposite sides through the parasitic gears 6 and the gears 7 from the shafts 8.

The internal cavity of the screw 2 consists of two parts: the upper conical and cylindrical. The conical part plays the role of a receiving funnel.

In the upper part of the screw 2 there is a gear 9, which receives rotation through the gears 10 from the shafts 8. In the lower part of the screw 2, a nozzle 11 is fitted, which serves to form the interface between the pipe layers. The nozzle 11 may be tapered or otherwise shaped to provide a molding process.

The screw 2 is located inside the matrix 12. The two half-rings 13 fixed on the matrix 12 are the support of the screw 2.

In the lower part of the die there is a sleeve 14 of variable inner diameter, having conical and cylindrical treads.

At the base 4 there are two bins 15 for supplying powder to the internal cavity of the matrix 12.

In the base 4 there are also two bunkers 16, the lower ranges of which are included in the conical part of the internal cavity of the screw 2.

The upper base 4 is fixed on a cylindrical support 17, which is fastened with the aid of ribs 18 also to the matrix 12.

The device works as follows.

The powder from the hopper 16 is fed to the receiving funnel, which is the inner conical part of the inner cavity of the screw 2. As the insert 1 is rotated, the powder moves to the pressing zone. In the region between the conical part of the rod 3 and the cylindrical part of the nozzle 11, the inner layer of the pipe being manufactured is formed.

The powder from the hopper 15 is fed into the internal cavity of the matrix 12. When the screw 2 is rotated, the powder moves to the pressing zone. In the area between the conical part of the sleeve 14 and the conical part of the nozzle 11 is the formation of the outer layer of the manufactured pipe. Thus, the cone head 11 takes part in the formation of the outer part of the inner layer and the inner part of the outer layer of the pipe being manufactured. From the gap between the rod 3 and the sleeve 14, a one-piece two-layer pipe is pressed out, which is then cut into blanks of the required length for sintering.

To prevent sticking of the powder in the region between the liner 1 and the cylindrical inner part of the screw 2, the screws 1 and 2 rotate in the opposite direction, which is ensured by the inclusion of parasitic gears 6 in the kinematic drive circuit.

The proposed device allows to ensure the continuity of the technological process of manufacturing double-layer pipes and increase labor productivity,

This is achieved by using a screw extrusion in combination with a nozzle to simultaneously form the outer and inner surfaces of a double-layer pipe.

The device also makes it possible to obtain two-layer pipes of a practically unlimited set of lengths, since the length of the two-layer pipe being manufactured is not structurally connected with any elements of the device. The required length of the pipe can be obtained in the process of separating it from the continuously extruded part of the pipe, while in the known device the length of the pipe is structurally related,

At least, with two elements of the device: the matrix and a stepped liner.

The device provides wider possibilities for automating the process of producing two-layer pipes from powder materials, since only the beginning and the end of the process for the production of two-layer pipes are periodic, namely, the filling is periodic.

the metal powder into the bins and the separation of the desired length of the manufactured pipe, whereas in the known device for forming a two-layer t-rub out of the metal powder, the outer layer and

The inner layer is molded sequentially, and the manufacturing process for producing a single tube involves a series of twofold operations that are performed when the extrusion process is stopped.

Claims (1)

Invention Formula A device for pressing two-layer tubes of powder, comprising a matrix, a screw insert coaxially mounted therein and an actuator, characterized in that, in order to increase the productivity of the process and ensure its continuity, it is equipped with a sleeve of variable inner diameter and an additional hollow screw with its lower part, the nozzle is made with a conical surface at the level of the expanding part of the sleeve, the liner is made hollow and provided with a fixed stepped rod installed in it, and the screws are mounted Vanir rotatably around the axis.