RU2501629C1 - Compacting press - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to powder metallurgy, particularly, to compacting presses. Press comprises column-type foundation with top and bottom booms, top and bottom male dies secured thereat, container with powder located in vacuum chamber and container drive. Vacuum chamber comprises cover with opening accommodating top male die and bottom sealed at press bottom boom. Cover and bottom are rigidly interconnected by four L-like posts. Side surface is composed by sections one of which being rigidly connected with cover, bottom and two posts and including pipe for connection for evacuation system. Other sections are mounted at said columns to turn thereabout. Container drive comprises hydraulic cylinder secured at bottom boom, bearing frame arranged to displace relative to bottom male die including top crossbar with four links rigidly secured thereat to support said container and bottom male die opening, and bottom crossbar rigidly connected with top crossbar by said columns. Columns can displace in openings of bottom boom. Top crossbar is arranged inside vacuum chamber while hydraulic cylinder is mounted between press bottom boom and bearing frame bottom crossbar.

EFFECT: higher quality of articles from powders.

2 cl, 3 dwg

Description

The invention relates to metallurgical engineering and can be used in presses for pressing powder materials.

A known press for pressing articles of powder materials, in which the container is formed by pairs of fixed and movable vertical plates (see USSR author's certificate No. 1340901, priority from 04.24.1986).

The disadvantage of this press is the rectangular shape of the resulting product and the complex design of the additional drive of the movable pair of plates.

A press for pressing metal-ceramic powder materials adopted as a prototype is also known. , priority from 11/09/1971).

The disadvantage of the press, adopted as a prototype, is the inability to obtain when using modern materials with a dense structure without the formation of surface defects in the semi-finished product. In addition, the compression of hardly deformed powders is possible only at elevated temperatures in vacuum.

The technical result of the present invention is to obtain high-quality products from powder materials with a dense structure throughout the volume without defects on the surface of the semi-finished product.

The problem is solved by creating a press for pressing powder materials, containing a column-type bed with upper and lower traverses mounted on traverses, respectively, upper and lower punches, as well as a container with powder material, a drive for moving the container, a vacuum chamber with heating elements, in which a container with powder material is placed, wherein the vacuum chamber includes a lid that is sealed to the bottom of the press crosshead, the lid and the bottom being rigidly connected between each other by means of 4 L-shaped racks, and a side surface made in the form of sections, one of which, including a pipe for connection to a vacuum system, is rigidly connected to the lid, bottom and two racks, and the remaining sections are mounted on columns with the possibility of turning around them, the cover is made with a hole in which the upper punch is mounted for movement, the container moving drive includes a hydraulic cylinder mounted on the lower beam, mounted to move relatively of the lower punch a power frame including an upper cross member with 4 rods rigidly fixed on it, on which the container is mounted, and an opening for the lower punch and a lower cross member rigidly connected to the upper cross member by means of columns mounted for movement in openings made in the lower traverse, while the upper cross member is placed inside the vacuum chamber, and the hydraulic cylinder is installed between the lower press traverse and the lower cross member of the power frame.

In addition, the heating elements of the powder material container are mounted on the inner surface of the sections and include heaters and multi-row sheet screens placed between the heaters and the inner surface of the sections.

The invention is illustrated by graphic materials, where:

- figure 1 is a General view of the press;

- figure 2 is a view of the press in plan;

- figure 3 - the sealing mechanism of the joints between the door leaves and the plane of the doorway of the camera.

The press contains a bed of 1 column type. Four columns 2 tighten the upper 3 and lower 4 traverses of the bed 1. In the upper traverse 3, a working cylinder 5 is installed, the plunger 6 of which acts on the movable traverse 7. In the movable traverse 7 connected to the plunger 6 of the working cylinder 5, the upper punch 8 with a stamp is installed (not shown in the drawing). A vacuum chamber 9 with heating elements 10 and a lower punch 11 with a stamp are installed on the lower traverse 4.

The mechanism for moving the container is made in the form of a power frame 12, the columns 13 of which are hermetically installed in the holes of the lower beam 4 with the possibility of movement. A hydraulic cylinder 15 for moving the container 16 is mounted on the lower traverse 4, which is installed between the lower traverse 4 and the lower cross member 14 of the power frame 12. An opening is made in the upper cross member 17 of the power frame 12, in which a lower punch 11 with a stamp is installed. Four links 18 are rigidly fixed on the upper cross member 17, on which the container 16 is placed.

The vacuum chamber 9 is made with a lid 19, in the opening of which the upper punch 8 with a stamp is hermetically mounted, and the bottom 20, hermetically mounted on the lower crosshead 4 of the press and which is the support of the chamber 9.

The lid 19 and the bottom 20 of the chamber 9 are rigidly interconnected by four massive L-shaped racks 21, and through the openings 22 into the chamber 9 the container and powder material are loaded. The lateral surface of the chamber 9 is made in the form of three sections 23, rotating around the columns 2 of the press due to the loops 24, which are tightened by hydraulic locks 25 to ensure sealing of the joints when a vacuum is created in the chamber 9. Also, the lateral surface of the chamber 9 includes a fixed section rigidly connected to the lid 10, the bottom 20, and two uprights 21 and the fixed section installed in the opening 26 with a pipe 27 connecting the vacuum chamber 9 to the vacuum system.

The container 16 with the powder material 28 is heated by four sectional heaters 29 mounted on the inner side of each section 23. Between the heaters 29 and the inner surfaces of the sections 23, multi-row stainless steel sheet screens 30 are installed in five rows. Since heat transfer under vacuum is mainly due to radiant heat transfer, the screens 30 due to the reflecting effect protect from heating the walls of the vacuum chamber and enhance the heating of the container 16 with the powder material 28.

Press works as follows.

In the initial state, the upper punch 8 with a stamp is in the upper position. The container 16 is placed on the rods 18 inside the vacuum chamber 9, while the stamp of the lower punch 11 is installed in the opening of the container 16 along a sliding fit at a certain depth, forming together with the container 16 a cavity closed on one side.

After turning around the column 2 of the press of one of the sections 23, a hopper-loader (not shown) is inserted into the opened opening 22 with powder material 28. When the hopper’s feed opening is combined with the opening of the container 16, the hopper latch opens and the powder material 28 is filled in the required amount into the working opening of the container 16 with the subsequent removal of the hopper from the vacuum chamber 9. During the operation of loading (unloading), the remaining sections 23 can also be open, which contributes to a more convenient holding ruzochno handling and ancillary works.

Then, in the cavity of the container 9, a press washer is installed on the powder material 28 (not shown in the drawing), and a stamp is fixed on the upper punch 8. In the next step, the hydraulic drive of the press is turned on and the upper punch 8 is lowered down to the stop of the stamp with the press washer, by means of which the powder material 28 is compacted, after which the sections 23 of the vacuum chamber 9 are closed and pressed with hydraulic locks 25.

Next, vacuum pumps are turned on and the required vacuum is created inside the vacuum chamber 9. In the process of creating a vacuum, at a certain vacuum, the heating elements - sectional heaters 29 - begin to heat the container 16 with the powder material 28 inside it to the temperatures required by the technology. The heating is carried out mainly due to the radiant energy coming from the sectional heaters 29 located at the minimum possible distance from the surface of the container and due to the reflectivity of the screens 30 installed between the heaters 29 and the inner surface of the sections.

After reaching the required temperature and vacuum values, the heating control system and creating a vacuum switches to the automatic mode of maintaining these values. During this mode, a certain level of stabilization of the vacuum and temperature is provided.

Then the punch 8 with the stamp is moved down and the powder material 28 is compressed in accordance with the specified deformation mode, while the speed and pressure of the press (pressure on the stamp) are maintained at the level required by the technology. To further activate the diffusion and self-diffusion processes in the powder material, the container 16 is forcibly moved relative to the powder billet 28 by moving the power frame 12 with the container 16 mounted on the rods 18 due to the operation of the hydraulic cylinder 15.

The shift of the container 16 in the zone of contact of its surface with the powder material 28 in the specified modes allows to obtain high-quality materials with a dense structure without surface defects in the semi-finished product.

Claims (2)

1. Press for pressing powder materials containing a bed of a column type with upper and lower traverse, upper and lower punches mounted on the traverses respectively, as well as a container with powder material, characterized in that it is equipped with a drive for moving the container, a vacuum chamber with heating elements, in which a container with powder material is placed, while the vacuum chamber includes a lid made with an opening in which the upper punch is mounted to move, and hermetically a bottom fixed on the lower press crosshead, which are rigidly interconnected by means of 4 L-shaped racks, and a side surface made in the form of sections, one of which includes a pipe for connecting to a vacuum system and is rigidly connected to the cover, bottom and two racks and the remaining sections are mounted on columns with the possibility of rotation around them, the drive for moving the container includes a hydraulic cylinder mounted on the lower traverse, mounted to move relative to the lower punch the power ra mu, including the upper cross member with 4 rods rigidly fixed on it, on which the container is mounted, and an opening for the lower punch and a lower cross member rigidly connected to the upper cross member by means of columns mounted for movement in the holes made in the lower crosshead, the upper cross member is placed inside the vacuum chamber, and the hydraulic cylinder is installed between the lower press beam and the lower cross member of the power frame. 2. Press according to claim 1, characterized in that the heating elements of the powder material container are mounted on the inner surface of the sections and include heaters and multi-row sheet screens placed between the heaters and the inner surface of the sections.

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