SU1447571A1 - Die-casting mould for making articles of bushing type from metallic powders - Google Patents

Abstract

The invention relates to the field of powder metallurgy, in particular to molds for the manufacture of articles such as a sleeve of metal powders. The goal is to expand the technological capabilities of the mold by ensuring that sintered billets are calibrated in it. Before pressing, the rod 2 is lowered to the lower position (until the conical collar stops in the conical section of the step on the inner surface of the die. After the powder is loaded, the pressing is pressed and the pressed billet is pushed out by reverse movement of the rod. After sintering, the resulting billet is calibrated. 180 ° A, the workpiece is placed above the slit formed between the second stage of the die hole and the rod centered with a tapered surface. echennuyu billet is pushed through br, fir, stem 2 is removed from it and the finished product is removed. The design features of the mold allowed to expand its technological capabilities. 3 yl.

Description

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The invention relates to powder metallurgy, in particular to molds for the manufacture of hub-type articles made from metal powders.

The purpose of the invention is to expand the technological capabilities of the mold by ensuring that sintered billets are calibrated in it.

FIG. Figure 1 shows the mold layout of the moment of pressing the preform; in fig. 2 is the same at the time of calibration of the outer diameter of the product; in fig. 3 - the same, in the mon.viCHT simultaneous calibration of the outer and inner diameters of the products.

The mold consists of a die I, a central rod 2, a punch 3 for pressing and a punch 4 for calibration. The matrix 1 is made in the central part of its stepped hole, while the diameter of the first step of the hole DI is equal to the outer diameter of the compression billet, the diameter of the second step of the hole D is the outer diameter of the finished product. The central rod 2 is made with three steps. The diameter of the first stage d is equal to the internal diameter of the workpiece, the diameter of the second stage d2. Is the diameter of the hole of the finished product, the diameter of the third stage of the rod ds is the diameter of the first stage of the matrix hole D.

The angle of the tapered parts of the matrix and the rod is selected within 10 a; 180 °, its e1: b; its value is limited by the condition that the conical surfaces do not self-brake when / g oi / (where / is the friction coefficient for steel, hardened HfaiX ii polished surfaces ,, 1}. The maximum value of the angle a is limited by the condition of the quality of centering, which is used at. The optimum value.

The proposed device works as follows.

Before pressing, the rod 2 is lowered to the lower position until the taper collar stops in the protrusion of the die I (Fig. 1), powder is poured into the cavity and punch 3 is inserted (Fig., Left}). When it is lowered, the powder is compacted (Fig. 1, on the right), the pressed billet is pushed out of the die by the movement of the rod 2 in the direction opposite to that of the extrusion. The pressed seals are fed to the bending operation.

When calibrating the outer surface of the sintered billet, it is set to

five

g

0

five

ZO

40

45

Nose hole of the matrix and push the movement of the rod 2 (Fig. T).

To calibrate the outer and inner surface of the preform, the mold is rotated 180 ° (Fig. 3), the preform is positioned above the gap between the second step of the orifice of the die I and the rod 2, which is in the upper position and centered relative to the die with the tapered surface of the collar (Fig. 3 on the left). Then the movement of the punch 4 down the workpiece is pushed through the slit, remove the rod 2 and remove from it the finished product (Fig. 3, right). Due to the elastic expansion, the part is removed from the rod freely.

Thus, the application of the proposed mold allows its technological capabilities to be expanded by providing in it conditions for pressing the powder and calibrating the sintered products.

In addition, the application of this mold allows to increase the dimensional accuracy of bushings and rings made of powder by 1-2 classes. This is achieved by combining the pressing and gauge parts of the rod and die in one piece, centered between each other with a conical step, which is their own position to zero, and the error of the form bar, the ar and the rod with the same installations are greatly reduced.

Claims (1)

Invention Formula A mold for the manufacture of products such as metal powder bushings, including a die, a central core, a powder filling cavity, and an annular punch, characterized in that, in order to expand the technological capabilities of the mold sl, to ensure the calibration of the sintered billet in it, the cavity the matrix is made of a part with a tapered transition, the rod is made of variable d., while the diameter of the middle part of the rod is equal to the diameter of the cavity of the matrix, the cavity for filling the powder is placed between the lower part of the rod and the wall of the matrix, between the lower part of the rod and the smallest diameter; the cavity of the matrix cavity forms a cavity for accommodating the sintered billet, and the transitional section between the middle and lower parts of the rod is made conical and conjugated with a conical transitional part matrices. FIG. 2