CS200947B1 - Method of pressing a die of a high-pressure tool - Google Patents

Abstract

The invention relates to a method of pressing a die of a high-pressure tool, consisting of a safety sleeve made of soft steel and a certain number of pre-tensioning sleeves made of hardened steel, surrounding a matrix of cemented carbide. The die of a high-pressure tool consists of a safety sleeve made of soft steel, a certain number of pre-tensioning sleeves made of hardened steel and a matrix of cemented carbide. At present, the die is pressed in the following way, for example in a three-sleeve die. A third pre-tensioning sleeve is inserted into the safety sleeve made of soft steel, either hot or cold, and a second pre-tensioning sleeve is pressed into this to the final position. Partial pre-pressing is now carried out

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for molding a die of a high-pressure tool comprising a safety sleeve of mild steel and a plurality of hardened steel biasing sleeves surrounding the cemented carbide matrix.

The die of the high-pressure tool consists of a safety sleeve made of steel, a plurality of hardened steel pre-tensioning sleeves, and a cemented carbide die itself. At present, the die is pressed in the following manner, for example, in a three-socket die. A third biasing sleeve is inserted into the soft ooeli safety sleeve by hot or cold, and a second biasing sleeve is pressed into the final position. The partial pre-pressing is now carried out

200 947

200 947 own dies into the first prestressing sleeve. The preformed assembly (die + first biasing sleeve) is inserted into the assembly (safety sleeve + third and second biasing sleeves) and pressed onto the intermediate pad. The die is then finished to its final position in the first biasing sleeve. Only then is the washer removed and the assembly (die + + first biasing sleeve) pressed into the final position in the assembly (safety sleeve + third and second biasing sleeves).

A disadvantage of the described method is, in particular, that the pressing of the die itself into the final position in the first biasing sleeve is divided into two parts, namely pre-pressing and pressing. However, this process has the additional disadvantages mentioned below.

When preforming the matrix itself into the first biasing sleeve, different deformations occur at the interface of the supported and unsupported surface on the inner radius of the sleeve and damping creates a sleeve material. After pressing the assembly (matrix + first prestressing sleeve) into the assembly (safety sleeve + third and second prestressing sleeve), the deformation on the inner radius of the first prestressing sleeve in the unsupported part increases again and thus increases the overlap at the active pressing edge of the matrix itself. In the final position, the die must overcome the initially formed preforms. At this stage, a very high point load of the active die edge results in cracks and later destruction of the cemented carbide matrix M under cyclic operational stress on the die.

Furthermore, when the die pressing operation is divided into two parts, it is necessary to produce a first prestressing sleeve of a height such that the die itself is embedded in it after pre-pressing. After pressing, the die must be placed in the safety area for 24 hours. Only then the first hardened steel pre-tensioning sleeve must be turned to the actual dimension. Despite the increased cost, there is a further loss due to the time delay during which the die can be deployed for diamond synthesis.

These disadvantages are overcome by a method of pressing a die of a high-pressure tool consisting of a soft ooeli safety sleeve and three or more pre-filled hardened steel sleeves enclosing the cemented carbide matrix of the present invention, characterized in that a sleeve in which a central biasing sleeve is partially molded by means of a lower stop washer, into which a partially internal biasing sleeve is pressed by means of an upper stopping washer and continuously pressed into the internal biasing sleeve of the die, then removing the upper stopping washer and pressing the die and a central biasing sleeve, after which the lower stop washer and the die assembly thus formed, the inner and middle biasing sleeves are pressed into the final positions in the outer prestressing sleeve.

A significant advantage is the elimination of the disadvantageous pre-pressing and compacting operation, in which the service life of the cemented carbide matrioe due to the contact of the cemented carbide with the hardened ooeli in two operations is negatively affected. This operation was transformed into the compression molding of the pre-tensioning sleeves made of hardened ooeli, ie ooel onto oeel, while the pre-pressed sleeves of the grooves3

200 947 sew the matrix together. This procedure eliminates the above disadvantages and is also suitable for multi-chamber dies. A further advantage is the use of a pre-tensioning sleeve of the desired height, thereby eliminating the additional laborious and lengthy turning of the hardened inner pre-tensioning sleeve. This procedure shortens the recovery time of the die and reduces the cost of crimping the incapable die.

In the drawing, FIG. 1 shows the high-pressure tool assembly, and FIG. 2 shows the principle of pressing the high-pressure die.

In the drawing, FIG. 1 shows a high-pressure tool consisting of a cemented carbide matrix 1 surrounded by a number of, for example, internal, central and external biasing sleeves 2, 3, 4 of hardened steel protected by a security sleeve 6. FIG. 2 shows the principle of assembly by pressing with the upper stop washer 6 and the lower stop washer

OF.

The new method of crimping a high-pressure die is explained on a three-sleeve die, but also for a multi-sleeve die. Into a mild steel safety sleeve 4, heat-press an external pre-tensioning sleeve 4 of hardened steel (e.g. Then insert the assembly into the press and press the central prestressing sleeve 3 onto the lower stop pad 7. Press the inner prestressing sleeve 2 into the central prestressing sleeve 3 onto the upper stopper 6 and press the cemented carbide matrix 1 without interruption. press the upper stop washer 6 and the assembly (matrix 1 + inner biasing sleeve 2) to the final position in the middle biasing sleeve 3. After removing the lower stop washer 7, press the assembly (die 1 + inner biasing sleeve 2 + middle biasing sleeve 3) to the final position In this way, the complete pressing of the die is completed and the die is operable. The principle of the proposed method advantageously breaks down the pressures, friction, biasing and other invoices by continuously and one-time pressing of the die 1 onto the other parts of the tool namely the biasing of the sleeve, whereby these factors are compensated by steel-to-steel contact.

Claims (2)

SUBJECT OF THE INVENTION A method for molding a die of a high-pressure tool comprising a mild steel safety sleeve and three or more hardened steel prestressing sleeves encircling a cemented carbide matrix, characterized in that an external prestressing sleeve is hot-pressed into the safety sleeve into which partially press the middle biasing sleeve by means of the lower stop washer and the inner biasing sleeve is again partially pressed by means of the upper biasing sleeve and then the matrix is continuously pressed into the inner biasing sleeve, after which the upper stopping washer is removed and and medium 200 047 of the biasing sleeve and the assembly thus formed is pressed to the final position outside the biasing sleeve after removal of the lower stop washer, 2. The method of zallification of a die of a high-pressure tool according to claim 1, characterized in that at least one biasing sleeve is pressed between the outer biasing sleeve and the central biasing sleeve.