CS206944B1 - Agent for fasilitation of ceramic products wet pressing - Google Patents

Description

P o INVENTION U

R E P U B L I C A C A C A C A C A C C A C I C IO 206944

(11) (MI (51) Int. Cl.i * 3B28B 3/00)

(22) Registered 13 09 79 (21) (PV 6180-79) (40) Published 15 09 80 (45) Released Ol 07 84

INVENTORY OFFICE DISCOVERY:

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Author of the invention JIROUSEK LUDVIK ing., STEŽERY, PETRÁČEK FRANTIŠEK, ŽACLÉŘ,

- ======== ^ = - ELEFANT MILOŠ ing., BRNO and FORAL JIŘÍ ing., ZASTÁVKA U BRNA (54) The device for facilitating the pressing of ceramic products for raw and the invention relates to a means to facilitate pressing ceramic products raw. A large proportion of ceramic products are formed by molding, in which a large precision and dimensional dimension is obtained. The pressing technology puts two main requirements on the processed material, namely:; the requirement for a balanced density of the raw molding, ie. as uniform as possible, and to achieve the highest possible average density. These requirements are aimed at achieving the greatest possible and uniform firing shrinkage, which results in reduced distortion, cracking and dimensional inaccuracies. In order to obtain a higher density of the material in the pressing tools and thus the equalization of the compacts, the mass is moistened with some hydrocarbon fractions such as kerosene, diesel, lower mineral oils, etc. The hydrocarbon fractions themselves are poor ceramic materials. Their lubricating ability r is improved by the addition of various additives, e.g., organic acids with as many carbon numbers as possible in the molecule, i.e., elaine, or acidic blends. Moreover, these additions prevent sticking of the material to the pressing tools. The most commonly used means for facilitating the pressing of ceramic products into raw materials is pressing oil, the main component of which is kerosene. The disadvantage of the aforementioned molding agents, however, is that they are used; 206944 decomposition fires into fumes that clog the pit exhausts. The chimney must be removed from time to time by burning it, since it often ignites uncontrollably, and the suction chimney fan is almost always destroyed if direct injector suction is not used. When fired in round kilns, it is contaminated with odorous fumes at the beginning of the firing. Fumes produced by spa-; by molding said means for facilitating the press; especially because they contain; sulfur compounds that corrode chimney exhausts (pipes, closures, etc.) contaminate the furnace surroundings (deteriorate the working environment) and destroy surrounding vegetation. From skin tests performed it has been shown that the pressing oil causes inflammatory changes. For this reason, the pressing oil has been recommended for work, coming into normal contact with unprotected and human skin.

The above-mentioned drawbacks of the state of the art are substantially eliminated by the invention, the principle being that 0.5 to 15% by weight of a lightweight polypropylene oil fraction of molecular weight 170 to 210 is used per 100 parts of molded mass: either alone or in a mixture with 0.05 to 5% by weight of oleic acid and 1 to 20% by weight of water.

The lightweight polypropylene oil fraction, called volatiles, is a mixture of C hydrocarbons (1 to Cl 4).

Claims (2)

206944 (predominantly represented by isoalkenes). They are strongly branched with one double bond in the molecule. They have advantageous surface properties for flowing purposes. The viscosity of the volatiles is 1mPa.s / 20 ° C, the molecular weight is 170 to 1210 and the density is 0.78 g / cm 3. Volatiles are produced by the production of polypropylene oil from which they are stripped. The advantage of volatile constituents is that they are not aggressive to human skin, as resulted from skin tests performed in Centers of Work and Occupational Diseases and Institute of Hygiene and Epidemiology. Volatiles do not contain sulfur and therefore do not produce compounds corroding metal parts of the exhaust. Combustion volatiles produce harmless fumes that do not endanger the environment, which has been proven. The use of volatile compounds in the rubber industry will bring economic benefits (lower costs for molding tools, less corrosion of metal parts of flue gas ducts, it is assumed lower reject rate in raw goods), furthermore energy (volatile constituents are a waste product, while the essence of compression oils is kerosene), working conditions will also improve (skin tests are more favorable for volatile compounds than for compression oils) and destroying surrounding vegetation. The invention will be explained in more detail with reference to five examples of possible embodiments of the invention. EXAMPLE 1 Wet granules for dry pressing of steatite products are disclosed. The batch had the following composition: 50 kg of steatite granules (with 1.8% water moisture) 0.5 kg of water 1.25 kg of volatile proportions of polypropylene oil 0.5 kg of elain The wetting was carried out in such a way that the weighed amount of granules was introduced into The drum mixer was wetted with pre-prepared false water, elain, and volatile components with stirring. The wetting emulsion was injected into the granules by spraying. The granules were discharged into the conveyor and conveyed to the presses after perfect homogenisation. Further work, pressing of the products, was common and identical with the current technological progress of the plant. Example 2 Wetting of crushed filter presses intended for overflow molding of electrical installation porcelain products is shown. The batch had the following composition: 225 kg of raw porcelain crumb (4% moisture) SUBJECT, 1. A composition for facilitating the pressing of ceramic products to a cheese characterized in that per 100 20 1 of a mixture of volatiles and elain (a mixture of The weight of the porcelain pulp was weighed out of the mixer, in which the raw pulp was sprinkled with a measured amount of the volatile mixture of elain. Then the mass was moistened with water, from the dosing device. The humidified mass, after complete homogenization, was allowed to drop and the collagen disintegrator into the conveyor and conveyed to the presses. Product stamping was common. Example 3 Moisture of crushed pyrostatic coils is shown. The batch contained: 120 kg of pyrostatic crumb 1 1 volatile fraction of 0.21 elain (i. 10 l of water) The weighed amount of pyrostatic crumb was wetted by the humectants in the mixer. Example 4 The dampening of cordierite mass is indicated, charge, having the following composition: 20 kg of cordierite raw crush 1.6 l of volatile fractions 0.051 elain: 31 of water. The moistened mass was thoroughly homogenized and sifted into the container and transported to the presses.The pressing of the products was common Example 5 The damping of the fireclay mass was indicated, containing: 80% by weight of the burnt fraction 0 to 3 mm t 20% by weight of clays Bp fraction below 0.09 mm: 3 wt% volatile mixture h parts with elain (the mixture contained 97% by weight of volatiles and 3% by weight of elain) 3% by weight of water; mixer in which the batch was mixed and moistened. The perfectly homogenized mass was conveyed to the hopper of the high pressure hydraulic press by a belt conveyor. Product molding was common. BACKGROUND OF THE INVENTION Parts of the molded material use 0.5 to 15% by weight of a light fraction of polypropylene oil of molecular weight of 170 to 210, either alone or in admixture with 0.05 to 5% by weight of oleic acid. 206944 2. A composition for facilitating the pressing of ceramics to cheese according to claim 1, comprising from 1 to 20% by weight of water.