CS255822B1 - Apparatus for making a ceramic body with a honeycomb structure - Google Patents

Abstract

The device for the production of ceramic bodies with a honeycomb structure has 2 systems of channels - feed and connecting. The feed channels, usually cylindrical holes or grooves, are guided in the direction of the axis of the device and the ceramic mixture into the connecting channels, which are formed by a system of grooves in the negative shape of the honeycomb structure. The feed channels have a larger cross-section than the connecting channels. The device finds application in the ceramic industry, the sintered materials industry, etc. in the production of bodies with a honeycomb structure, usable as filters, gas distributors, catalyst carriers, fillings for reaction columns, etc.

Description

The invention relates to an apparatus for producing a ceramic body having a honeycomb structure, i.e. a ceramic body, comprising a plurality of continuous parallel channels, preferably straight, separated by partition walls.

At present, ceramic bodies, longitudinally perforated, with high hole densities of up to 200 / cm and the associated small hole dimensions are needed in many technical fields. They can be used, for example, as filters for liquids, liquid metals, gaseous substances, etc. , as catalyst supports, gas distributors in burners, reaction column packings instead of traditional Raschig rings, etc. Body dimensions, shape of through holes (channels) and ceramic material of the body must be suitable for the intended use. The use of non-circular channel cross-sections, i.e. triangular, quadrilateral and hexagonal, seems advantageous.

a frequent requirement is that the inner surface of the channels is as large as possible, and this leads to a requirement of 2 for high channel density bodies, 50, 100, but also 200 holes per cm. The thickness of the partition walls between the ducts is required to be 0.1 to 3.0 mm, and all this is difficult to accomplish by known technological methods. Bodies with a small overall length and a not very high hole density can be produced by pressing the ceramic mixture in a tool which is provided with a set of needles inside to form the respective holes. This can only be used up to a hole density of approx. 10 to 20 / cm and a length of approx. 30 mm. Long bodies can be produced by drawing technology on a worm or piston press, the inside of the press being equipped with a set of mandrels that create the desired holes.

This can be used for a maximum hole density of approx. 10 to 20 / dm. In the case of long bodies with high hole densities, these known technologies fail.

Ceramic bodies having a honeycomb structure in cross-sections with external dimensions characterized by a circumscribed circle with a diameter of up to 500 mm and a length of up to 5,000 mm can be manufactured with the device according to the invention. The thickness of the partition walls can range from 0.1 to 20 mm, the number of holes _in 2 to 250 per 1 cm.

The object of the invention is a device (which can also be characterized as an extrusion tool) comprising two sets of channels. The first set of channels, referred to as feeders, is formed by a set of holes, preferably cylindrical, drilled, or a set of grooves, which serve to feed the preformed ceramic mixture to the second set of channels. This second set of ducts, called connecting, is connected to the supply system and is formed by a network of grooves in the negative shape of the honeycomb partition walls.

In a preferred embodiment with cylindrical feed channels, the feed channel axis is identical to the intersection axis of the coupling channel.

In another preferred embodiment, the cylindrical supply ducts are replaced by a set of grooves, in cross-section adjoining the axis of the duct and extending in the direction of the duct.

The thickness of the partition walls need not be uniform; it can be adapted to the user's needs. A special thickness can also be chosen for the surface layer of the ceramic body with a honeycomb structure. This surface layer is formed by separate supply and connection channels that surround the honeycomb channel systems.

The attached drawings show various types of bodies with honeycomb structure and a tool for their creation.

Giant. 1 is a view of a square honeycomb body with a honeycomb; FIG. 2 shows triangular structures; FIG. 3 shows a diagram of a hexagonal structure. Other schemes are possible. Fig. 4 is a cross-sectional view of the die, Fig. 5 is an oblique view of the tool from the side of the ducts, and Fig. 6 is a view of the tool against the direction of formation, ie, the side of the ducts. For the sake of simplicity, FIG.

In all figures, the reference numeral 1 denotes the feed channel, the reference numeral 2 the coupling channel, the reference numeral 2 the circumferential channels and the reference numeral 4 the outer wall of the tool.

Claims (3)

SUBJECT OF THE INVENTION An apparatus for producing a ceramic body having a honeycomb structure, i.e. a ceramic body with a set of parallel channels of different, preferably non-circular cross-section, characterized in that it consists of two sets of channels, the first of which the direction of the axis of the apparatus for supplying the ceramic mixture to the second system, which is arranged downstream of the supply channels, is called the connecting channel and is formed by a system of grooves forming a negative shape of the honeycomb structure. a duct surrounding the entire duct system. Device according to claim 1, characterized in that the supply channels are connected to the intersections of the connecting channels. Device according to claim 1, characterized in that the supply channels are in the form of grooves, which open into the connecting channels.