SU755607A1 - Method of pressing annular tablets - Google Patents

Description

The invention relates to a method for the production of ring tablets carried out on tablet machines, and may find application in the chemical industry for tabletting catalysts for cracking processes.

There is a method of tableting ring tablets [1], which includes methods of filling the press mass into a mold, compressing it between the upper and lower punches in the annular cavity formed by the mold core and the axial mandrel, until the mandrel is extracted from the pressing hole and then moved lower punch to the top level of the mold.

The molded compact is tightly molded with a ^15- meter mandrel. When removing the mandrel from the hole due to the presence of large friction forces on the compact there is a significant tensile strength, which is greater, the greater the formation force of the compact. 20 In the production of compacts from poorly pressed or hardly pressed materials, the indicated breaking strength can lead to their destruction.

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The aim of the invention is to obtain compacts from hard-pressed materials with the correct geometric shape of the ring, increasing the height of the compacts, as well as increasing the productivity of the method and reducing its cost.

This goal is achieved by the fact that in a known way, when removing the mandrel from the hole of the molded compact, it is compressed with punches with a force not lower than the breaking strength of the destruction of the compact.

FIG. 1 shows a device for implementing the proposed method in section; in fig. 2-4 show techniques that characterize the method; in fig. 5 and 6 - ring-shaped compacting, obtained respectively by the known and proposed methods.

The proposed method is carried out in the following way.

Material 2 is poured into the mold 1. The bottom of the form 1 is formed by the lower punch 3 with the rod 4. When the lower 3 and upper 5 punches come together, the material is pre-compressed, and then the mandrel 6 is inserted into it and the

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the final convergence of the punches 3 and 5 for the formation of the finished pressing 7. After that, the mandrel 6 is removed from the opening A of the pressing and the pressing is compressed by the punches 3 and 5 with a force not less than the breaking force of the destruction of the pressing. The magnitude of this force is created, for example, by means of a spring 8 acting on the upper punch 5. After removing the mandrel 6, the upper rod 9 is raised along the pressing 7 together with the punch 5 and the mandrel 6, and the lower punch 3 moves the pressing 7 to the upper level B of the mold 1, after which the pressing is ready for transportation to a team container. FIG. 6 shows the geometric shape of the pressing ring 7, obtained by the proposed method from any press materials. In a known manner, it is possible to obtain a compact, only of such a form as shown in FIG. 5. Such pressing has a tapered hole K with a radius of K and less weight as compared with pressing 7.

The application of the proposed method will allow to obtain compacts with the correct geometric shape from any press-mate4

rials and any size in height while increasing the productivity of the method compared with the prototype by 10-15%.

Claims (1)

Claim The method of pressing the annular tablets from the powder material by filling the latter into the mold, compressing it between counter-moving punches with the mandrel tablet being inserted into the material that forms the opening, then extracting the mandrel from the compressed tablet, in order to increase the height of the compressed tablets, as well as improving the accuracy of the geometric dimensions, when extracting the mandrel from a compressed tablet, create a crimping force on the ends of the tablet, no less Ine is the breaking force of destruction of a compressed tablet.