DE1902707A1 - Press tool set - Google Patents

Description

Joseph Lucas (Industries) Limited I yU / / U /

Great King Street,

Birmingham / England 16th January 1969

25 022 Ma / He

Press tool set

The invention relates to a press tool set consisting of a hollow press mold and a press ram which is used for sintering a refractory non-metallic material such as silicon nitride under high pressure.

The press tool set is placed on a flat press table and is provided with a plug which is inserted into the mold and which also comes to rest on the press table.

The invention particularly relates to a die set for making products from refractory material with an opening that runs through the entire thickness of the material extends through it and in which there is a driving mandrel which defines said opening.

The purpose of the present invention is to provide a die set to create, which enables the production of annular press products in a particularly cheap and effective way.

According to the invention, the press tool set is characterized in that that the punch and a driving mandrel or part of such Driving mandrel are made from one piece.

According to Glnern, another aspect of the invention; the press _{tool (} ; r - ;. i.t2 is characterized in that the driving mandrel is designed in two parts i. ^c ; t and thus has a separate part.

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The invention is intended below on the basis of exemplary embodiments and will be explained in more detail with reference to the accompanying drawings.

Show it:

Pig. 1 shows a press tool set constructed in accordance with the invention is and the

Figs. 2 and 3 show a modified form of the press tool set in successive Working positions.

In Fig. 1, a die set is shown, which is a tubular Has the mold 10, which is placed on a flat press table, which is indicated with 11. Inside the die 10 and in the support with the press table 11 is a plug 12 in Shape of a ring.

A ram 15 is inserted into the mold 10, wherein a High pressure on a batch of non-metallic powder material, for example silicon nitride, denoted by 14 is exercised.

The punch has a one-piece driving mandrel 15, with a central opening running through the whole finished silicon nitride product extends, is formed, which is thus pressed out in the shape of a ring.

The parts 10, 12, Ij5 and 15 of the die set are molded from graphite and a high pressure is exerted on the punch in order to compress the silicon nitride charge 14- within the die. The pressures can for example reach a size of 100 kg / cm and the parts are also heated ^{to a temperature of about 17CO 0 C.}

The mold is filled with silicon nitride before the press cu'uck begins is carried out by pressing the die 10 and the punch Γ- ' opposite to the position shown in Fig. 1 are placed. The stopper 12 vvu'd inserted before the Preßwei'iczeiigaafc :; in

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is placed in an inverted position on the press table 11.

In the embodiment shown in FIGS. 2 and j $, is also a tubular die 16 is provided in which, in which a plug 17 is arranged and between the plug 17 and a stamp 18 is a charge 19 of silicon nitride. The punch 18 has one made in one piece with it Driving mandrel 21. Part 20 of the driving mandrel 21 is removable.

As shown in Fig. 1, the die set is made with a silicon nitride charge filled, with the parts in the inverted position, as shown in Fig. 2, are. An opening in the silicon nitride charge is made of parts 20 and 21 of the driving mandrel certainly. The stopper 17 is placed on the top of the batch and is also attached to the removable part 21 of the driving mandrel held. A compressive pressure is now exerted on the plug 17 in order to produce an initial cold compression of the silicon nitride charge 19 perform and when the upper part 20 of the driving mandrel enters the plug 17, the removable part 21 of the driving tool removed, the parts are reversed and on a flat press table 22 of a press as shown in FIG is put on. Then the full pressure is on:? the punch 18 exerted a final pressing of the charge 19 of silicon nitride to be carried out in the presence of the high winter temperature.

Patent claims:

909836/0257 ORIGINAL BATHROOM

Claims (5)

Patent claims before: 1. A press tool set consisting of a hollow press mold and a press ram, that for sintering a refractory non-metallic material under high pressure, such as silicon nitride serves, which can be placed on a flat press table and is provided with a plug which is inserted into the mold is and also comes to rest on the press table, in particular for the production of annular pressed products, thereby characterized in that the punch (IJ, 18) and a driving mandrel (15) or a part (20) of this driving mandrel are made in one piece. 2. Press tool set according to claim 1, characterized in that the mold (10, l6) is tubular and the plug (12, 17) is annular are trained. 3. Press tool set according to one of claims 1 or 2, characterized in that that the driving mandrel (20) is constructed in two parts and has a separate part (21). 4. Method of making an annular sintered refractory Non-metallic product, characterized by inserting a Ste ^ relü (I3) with a one-piece Driving mandrel (15) into the interior of a hollow press mold (10), introduction a batch (14) of a refractory non-metallic powder material in the mold, placing a stopper (12) on the batch '(14), reversing the assembly consisting of the die, punch and stopper, placing the same on a flat Surface (II) and applying a pre-print to the stamp (13) with simultaneous heating of the charge (14) for sintering it. 5. The method according to claim 4 ^ characterized by pre-pressing the charge (19) after assembly and .rc reversing the assembly, Er.iierr.eri of a part {- ') of the driving mandrel 909836/0257 BATHROOM OBlGlNAL (20 ), reversing the assembly and applying the final pressing pressure to the punch (18) while heating against the flat surface (22). 909836/0257 Blank page (ο