RU2388595C1 - Moulding set to mould large-sizeceramic articles from water slips - Google Patents

Abstract

FIELD: process engineering. ^ SUBSTANCE: invention relates to ceramic industry. Proposed moulding set comprises moisture absorbing lower die, core including support flange, central core and nose tip and assemblies for their mutual mounting and make-up. Central core surface is formed by plates made from low friction factor material, for example fluoroplastic, and shaped to workpiece inner profile. At the center of every plate there is a hole with diametre mating that of central core. ^ EFFECT: reduced labor input and costs, higher efficiency.

Description

The invention relates to the ceramic and aviation industries and can mainly be used when molding by slip casting of aqueous suspensions into porous forms of ceramic products such as nasal dielectric cones of aircraft.

A device for molding ceramic products from aqueous slips (patent for the invention of the Russian Federation No. 2133928, B28B 1/26), including a moisture-absorbing matrix, a forming model, a core with a support flange and a forming rod, make-up containers, in which the matrix is detachable in the lower part and equipped with a housing with a Central hole, fixing the toe of the model, while in the body coaxially with the Central hole is placed a centering rod with the possibility of axial movement.

This device has a significant drawback that impedes the production of high-quality workpieces during molding.

The device is based on the idea that the set of wall thickness of the product is uniform over the entire surface, which is not true. Since the process of forming a workpiece is accompanied by complex physicochemical processes, which result in shrinkage of the products. As a result of shrinkage of the workpiece on a rigid core, its destruction occurs. Given these technical aspects of casting products from water slurries, it becomes obvious that technical solutions for producing equally thick blanks do not ensure the integrity of the products, which is observed in practice.

The closest in technical essence to the claimed solution is a device for molding ceramic products from water slips (patent for the invention of the Russian Federation No. 2191688, B28B 1/26), including a moisture-absorbing matrix, a core, including a support flange, a central rod and a sock made with a lining of hydrophobic material, which is used as an elastic lining of microporous rubber, nodes for their mutual coaxial installation and recharge.

A disadvantage of the known device is the complexity and high complexity of the operation of applying an elastic lining on the working surface of the core. In addition, the elastic lining, as a rule, has low strength and is often damaged, which leads to the need for its replacement, and in fact to the manufacture of a new core.

The objective of the present invention is to reduce the complexity of production and material costs while improving the quality of products.

This object is achieved by the fact that a mold kit for forming large-sized ceramic products from water slips is proposed, containing a moisture-absorbing matrix, a core including a support flange, a central rod and a sock, nodes for their mutual coaxial installation and feeding, characterized in that the surface of the central rod is laid out plates made of a material with a low coefficient of friction, for example, fluoroplastic, and processed under the inner profile of the workpiece, with a hole in the center of each plate ies corresponding to the diameter of the central rod.

The authors experimentally established that after completion of the set, the workpiece begins to shrink in the horizontal and vertical directions. The use of a core with a working surface made in the form of plates of a material with a low coefficient of friction, for example, fluoroplastic, leads to the fact that the workpiece freely moves in height due to vertical shrinkage and thereby reduces stress caused by horizontal shrinkage. This positive effect is greater, the greater the taper of the molded product.

It is established that the implementation of the core in the form of plates laid on the central rod and processed under the inner profile of the workpiece, can significantly reduce the labor costs for its manufacture.

In addition, it was found that the implementation of the core from individual fluoroplastic plates allows to reduce material repair costs in case of damage to its working surface, since it is enough to replace only damaged plates.

The drawing shows a General view of the core. The core includes a support flange (1), a central rod (2), plates made of fluoroplastic (3), and a sock (4).

The core is manufactured in the following sequence: a central rod (2) is fixed to the support flange (1), onto which plates are placed having a central hole corresponding to the diameter of the central rod and made of a material with a low coefficient of friction, for example fluoroplastic (3), then the whole structure is tightened tightly with a sock (4), then the surface of the core is processed on a machine under the internal profile of the workpiece.

The operation of the mold kit is shown in the following example.

In a dried moisture-absorbing matrix, repeating the outer contour of the product, a core is installed on the seat on the matrix flange. The core with the help of nodes for their mutual coaxial installation is fixed on the support flange of the matrix. Make-up containers are installed on the core flange. Through the fitting in the lower part of the matrix fill the form with a slip. After completing the set of blanks, the core, and then the blank is removed from the moisture-absorbing matrix.

When implementing this technical solution, it was found that even with an additional 3-hour drying of the preform in the form assembled together with the core, its destruction does not occur as a result of the fact that the fluoroplastic layer perceives the deformation of the product, providing a reduction in its size and preventing destruction of the product, increasing it quality.

Compared with the prototype, the proposed technical device can reduce the time for the manufacture and repair of the core. The execution of the surface of the Central rod of the individual plates of the fluorine plastic also allows to reduce material costs, since only failed plates are subject to replacement.

The proposed device is extremely simple to manufacture and operate, it is especially successfully used in the molding of equally thick large-sized ceramic products from aqueous slips.

Information sources

1. Patent for the invention of the Russian Federation No. 2191688, 10.27.2002

2. Patent for the invention of the Russian Federation No. 21393928, 12/27/1998

Claims (1)

A mold kit for forming large-sized ceramic products from water slips containing a moisture-absorbing matrix, a core including a support flange, a central rod and a sock, units for their mutual coaxial installation and make-up, characterized in that the surface of the central rod is lined with plates of material with a low coefficient of friction , for example fluoroplastic, and machined under the inner profile of the workpiece, with a hole corresponding to the diameter of the central rod .