SU804050A1 - Female die for extruding articles - Google Patents

Description

(54) MATERIAL FOR PRESSING PRODUCTS

one

The invention relates to the processing of metals by pressure., Namely to the extrusion of products.

A known extrusion matrix containing successively placed a calibrating part and an output part with a central channel and a groove around a channel made in a spiral with evenly spaced coils along the end surface of the output part and forming a cavity connected to the surface of the calibrating part facing to it supply and removal of the cooling medium, made in the output part of the matrix 1 j.

Such a matrix, due to the inlet in its output part of the inlet of a larger cross section than the drain, ensures the complete filling of the strips; However, it does not provide high rates of outflow of the workpiece material, since the implementation of the spiral groove of a constant cross section over all its turns does not create a regulated heat removal from the die, which needs to be changed and adjusted (depending on the location of each turn of the groove on the surface). butt output 4acTf.

The purpose of the invention is to increase the rate of discharge of the workpiece material by creating a regulated heat sink from the die.

This goal is achieved by the fact that in a known matrix for pressing products containing successively placed a calibrating part and an output part with a central channel and a groove around the channel made in a helix with the coils uniformly located over the entire surface of the end face and forming the end of the calibrating part, the cavity connected to the holes for the supply and removal of the cooling medium, made in the output part of the matrix, the groove is made of variable cross-section, smooth o The output part decreasing from the center of the end face to its periphery

FIG. 1 shows a matrix, a general view in section; in fig. 2 - the same plan view.

Claims (1)

The matrix contains successively placed calibrating part 1 with point 2. equipped with calibrating unit 3, and output part 4 with central channel 5 and groove 6. Point 2 and channel 5 are coaxial with each other and have the same dimensions. Limited to sk 3, the walls of which are parallel to the axis of the die, the calibrating hole corresponds to the configuration of the section of the extruded product. The groove 6 is formed around the channel 5 in a spiral with 4 turns evenly distributed over the entire surface of the end of the output part, and the groove is made of variable cross-section, gradually decreasing as its coils move away from the channel 5. The groove 6 forms a cavity with the surface of the end face of the calibrating part 1 connected to the openings 7 and 8, serving respectively for the supply and removal of the cooling medium. The cross-sectional area of the inlet 7 is 1.1-1.2 times the cross-sectional area of the outlet 8. At the same time, the minimum cross-sectional area of the aperture 7 is equal to or less than the cross-sectional area of the aperture 8. The matrix works as follows . Before starting, it is installed in the die holder of the extrusion press. Then the billet (for example, from an aluminum alloy), heated to the temperature of technological plasticity, is placed in the cavity of the container of presses. By pressing the stamp, the workpiece is informed by the pressing force, under the influence of which its material begins to be squeezed out through the calibrating hole of the matrix point 2, forming a press-product of a given configuration. In this case, the material squeezed through the matrix is heated unevenly over the cross section of the workpiece: the workpiece material has the highest temperature in the vicinity of 2 points of the matrix, and the lowest in the peripheral layers. The gauge part I of the matrix, and therefore the whole matrix, which is in contact with the workpiece is also unevenly heated. Simultaneously with the commencement of the pressing process, a coolant is supplied, for example, water, which through the inlet 7 enters the closed cavity formed by the groove 6 and the surface of the gage part 1 facing it. The coolant flows successively through all turns of the groove 6 and is drained through an outlet 8, ensuring a constant circulation of the coolant in the cavity of the matrix. As a result of such circulation, due to the implementation of the groove 6 of variable cross-section, regulated heat is removed from the die and the material of the compression blank, i.e. heat is more intensively removed from the most heated surfaces of the calibrating part of the matrix and the layers of the workpiece material located near the point, and less intensively from the peripheral surfaces of the calibrating part and the layers of material. In this case, the temperature gradient over the cross section of the workpiece is leveled, therefore, the flow rates of the central and peripheral layers of the workpiece material located near the matrix are evened out, which leads to an increase in the flow rate of the material from the matrix point. At the end of the extrusion, the coolant supply is shut off. A press rod is separated by known means, the press product is removed, a new billet is introduced into the container and the cycle can be repeated in the above sequence. The use of the described matrix allows one to achieve that the MOJO regulates heat removal from the entire contact surface with the pressed material, leveling the flow rates of the central and peripheral layers of the material, which in turn increases the flow rate of the material through the matrix point. According to preliminary calculations, the use of the proposed matrix for extruding products from aluminum alloys will allow an increase in the rate of metal outflow by about 30% with obtaining products of good quality. DETAILED DESCRIPTION OF THE INVENTION Matrix for pressing a product comprising successively placed a calibrating part and an output part with a central channel and a groove around the channel, made in a spiral with evenly spaced coils on the end surface of the output part and forming a cavity connected to the hole for supplying and discharging the cooling medium, made in the output part of the die, characterized in that, in order to increase the flow rate of the workpiece material generating the heat removal from the regulated m.atritsy, the groove is formed with a variable passage section, a decreasing gradually from the center to the periphery of the end portion of the output matrix. Sources of information taken into account in the examination 1. USSR author's certificate according to application JVb 2643714 / 25-27, 11.06.78. -at .