DE3127556A1 - Refractory sealing material - Google Patents

Abstract

The invention relates to a refractory sealing material containing mixing values of from 50 to 90 % by weight of refractory fillers having a particle size less than 0.1 mm (based on dry content), 1 to 10 % by weight of fibrous refractories and 9 to 50 % by weight of plasticisers (plastificators). The mixture has been shaped into sheet or film form following the addition of a suitable amount of liquid.

Description

Fireproof sealing material

The invention relates to refractories and, more particularly, to refractories Sealing materials, which are filled in the Hoblräwuen, which in the lining materials of doors, ovens and containers or in the one in the fitting section of the blower and nozzle where molten metals are treated and metallic materials are heated are formed to protect the refractory lining materials and waste of fuels as well as uneven heating within to avoid a heating chamber.

In the conventional method of filling in white space or A pasty mixture is used for splitting, in which mortar, i.e. H. powdery Refractory materials, combined with binder and water and then kneaded.

The pasty mixture is poured into the cavities or crevices, where it dries by itself or is dried by warming or heating. There however, if water is released as it dries, cracks are likely to occur. Furthermore, such a filler material has inferior hot strength than that circumferential lining material so that erosion occurs at the joints and this occurs particularly in a molten metal container which is brought into contact with molten metal.

In an intermediate container or "tundish" in which a melted If metal flows, this is intended to prevent the melt from penetrating into the joint sections that a plate-like joint filling material on the seams of the lining panels is applied, but such a method requires an adhesive between the solid surfaces, so that there is hardly any affinity in between occurs and a sufficient adhesive or adhesive effect cannot be achieved can.

The object of the present invention is to increase the life of the liner to expand as much as possible, which could be short due to shrinkage or peeling, by the weak points of the adhesion of conventional mortar or the suction plate adhesion be avoided and a plastic, plate-like or foil-like, refractory Filler is used to fill in the voids or crevices, making the solid Surfaces are brought into closer contact.

The refractory sealing material according to the invention serves to solve this problem, which homogeneously 50 to 90 wt .-% of one or more refractories Fillers selected from the group of silicon dioxide, quartz sand, olivine, chamotte, Aluminum oxide, corundum, mullite, magnesia, dolomite, spinel, chromite, zirconium dioxide, Titanium dioxide, zinc oxide, brick or slag, each of these substances having a particle size of less than 0.1 mm, expressed as dry matter, has 1 to 10% by weight of one or more fibrous refractory materials selected from the group of asbestos, rock wool, slag wool, glass wool, kaolin fibers, aluminum oxide fibers, Magnesium oxide fibers, silicon carbide fibers and carbon fibers, as well as 9 to 50% by weight one or more plasticizers selected from the group of water glasses, Clays, especially Kibushi clay and Gairom clay, kaolin, bentonite, starch, dextrin, Glue, gum arabic, resins, latex and gum or gummuk, peeled, and to that Mixture of one or more liquids in a suitable amount selected from Group of water, alcohols, esters and hydrocarbons, added and then the mixture has been deformed in the form of sheets or foils after kneading.

The refractory fillers in the constituent elements the masses according to the invention serve to provide a compressive strength as an addition of the To deliver product and they improve the heat resistance by coating the surface of the refractory, fibrous materials. These fillers will appropriately depending on the molten metals from acid refractories like quartz sand, quartz, zirconium dioxide and titanium dioxide, the neutral ones Refractory materials such as fireclay, aluminum oxide, eorund, mullite, olivine and chromium oxide, the basic refractory materials such as magnesia, dolomite, spinel and zinc oxide and the Powders of bricks and slag based on them are selected. Preferably the particle size is smaller because of the easier formation of a uniform structure in molding the product, however, in practice it is with a smaller particle size than 0.1 mm possible to keep the structure almost uniform and the product in to such an extent as to be rolled thin into a sheet.

With regard to the content of the refractory fillers, no adequate refractory properties on the product with less than 50% of it achieved by shortening the life of the product, while at a larger one Amount than 90% of the content of fibrous materials relatively decreases, thereby reducing the Non-collapse properties deteriorated to an unacceptable extent will.

The fibrous refractory materials also serve to create the spaces between them between the aggregate particles to connect to the collapse in the environment from molten metal or a gas atmosphere, reducing the service life is improved in continuous casting.

The greater the length of the fibers, the more effective they are when however, if it is more than about 2 mm, they are in an acceptable range the costs and in terms of practical application. Farther different kinds of the refractory fillers are particularly preferred according to of the invention depending on the nature of the properties of the acidic, neutral or basic aggregate selected, however, the refractory fiber materials be used at any time, and if the temperature is not that high, they can only be selected taking into account the costs. This means, that the freely selectable, fibrous refractory materials in the range of the less expensive fibers such as asbestos fibers, rock wool, and slag wool Glass wool to expensive and highly heat-resistant fibers such as kaolin fibers, Alumina fiber, magnesia fiber, silicon carbide fiber and carbon fiber lie. If more than 10% in content, the fibrous refractory materials can either inhibit the heat resistance attributable to the aggregate or the improvements stop the refractory properties as a result of the type of fibrous materials, so that a content of more than 10% thereof is not advantageous, while if it is less than 1% fibrous materials, these are not present in sufficient quantity to fulfill their role of connecting the aggregate particles, causing them to collapse of the product is accelerated, so that a content of less than 1% also is not suitable.

Furthermore, plasticizers are added to the product becomes soft and can be applied depending on the shapes of the joints or cavities. The plasticizer gives the product flexibility in passage by a roll extruder or a dewatering type suction forming machine, wherein the plasticizer as such or in a heated state or with the addition of a Liquid such as water or an organic solvent can be present for this purpose, whereby the softness, d. H.

Plasticity at which the product is achieved. Hence the product not broken when bent or folded, and when inserted it fits the shapes of non-planar surfaces of cavities or crevices, so that it comes into close contact with the surfaces without the formation of gaps. That Plasticizer according to the invention has a property that the Volume of the product, even when preheated, hardly changed.

The plasticizers used according to the invention are homogeneous dispersed, with liquids, by mixing, water glass, chlorides of alkali or alkaline earth metals, water-soluble phosphate, clay, kaolin, bentonite, a starch, Dextrin, glue, gum arabic, water-soluble resins, solvent-soluble resins and rubber and high polymer compounds including petroleum products and coal dry distillation products.

The liquid can either be removed by drying or im Product can be left.

The plasticizer given with a content of less than 9% the product does not have a satisfactory softness, and if the amount is greater than 50%, the refractory properties of the product are deteriorated, so that both Cases are not suitable.

The liquids that are added when the materials are mixed are water, alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, glycerine and Glycol, esters such as ethyl acetate, amyl butyrate, ethyl butyrate and amyl acetate, ketones such as acetone and methyl ethyl ketone and hydrocarbons such as gasoline (petrol), kerosene, Benzene and toluene. Their type and the amount served will depend on the the degree of softening desired and depending on the adhesive conditions during use of the of the materials shown niche properties selected.

The inventive. refractory sealing material is such a one Way made that / predetermined amounts of refractory fillers and fibrous Refractory materials with the addition of a plasticizer, be it in powder form, heated or with the gradual addition thereof with the liquids, mixed, and once the plasticizer is uniformly mixed with the mixture, this is made in the form of sheets or foils by rolling or by means of an extruder or a suction drainage type molding machine, then the molding is formed cut to suitable length. If the plasticizer is solid, can it can be heated when heating or heating is not possible, e.g. B. at thermosetting resins, a small amount of organic solvent is used to dissolve added to the ingredients or to be converted into a colloidal liquid, and this liquid gradually becomes drop-shaped along with the mixing of the refractory fillers and the fibrous refractory materials mixed in. That The mixture prepared in this way is the same as in the method previously described extruded, and the extruded article is in the form of sheets or sheets cut. If the plasticizer is in aqueous solution, another Solution or emulsion is a mixture of the solid or powdered materials gradually added to the plasticizer during the mixing process. If If necessary, additional liquid is added to adjust the hardness. The deformation is carried out in the same way as in the previously described working methods carried out. If the product according to the invention is used for packs, etc., the pack can be made from the sheet or the film in the desired size or shape punched out or cut out.

The invention is explained in more detail below with the aid of examples.

In the information regarding the niche level, all other materials were used as the liquids expressed as percent by weight (wt%) based on dry content, the liquid data relate to parts by weight (parts by weight) of dry content, and in the comparative examples the data are in parts by weight. made.

Table example 1 2 3 4 5 Cf.

Example 1 Example 2 refractory sand containing quartz - - - 70 52 mixed and Fillers chamotte - - 65 - - kneaded like aluminum oxide 55 - - - - in example 1 magnesia - 60 - - - 100 teas.

Zircon flour - - 10 15 -fibrous - asbestos 10 - - - -ge fire rock wool - 8 - - 2 solid kaolin fibers - - 4 - -rial silicon carbide fibers - - - 1 -plastic 50% aqueous zierungs- solution of sodium agent polyacrylate - - - 14 -Polyethylene granules 15 - - - 30 40% vinyl acetate emulsion - - 21 - -vinyl chloride powder 20 - - - -more natural Rubber - 32 - - 16 MgCl2 solution, 28 ° Be 60 parts.

Table (continued) Ex. 1 2 3 4 5 Cf.

Example 1 Example 2 Liquid water - - - 30 -nuts n-hexane - 20 - - -Benzene - 30 - - 40 Methyl ethyl ketone 30 - - - -Methanol 20 - - - -Gestalt der Produkte Pl. Pl. Pa. Pl. Fo. Pl. Of 500 x mortar of from with of from 100 x 5 mm 500 x 500 x a 500 x 100 mm produced in 100 x 100 x outside 100 x width of the sequence 5 mm 5 mm through-5 mm and ge: Mixing, kneading 2 mm, forming starch, drying 200 u. And calcining an inner diameter of 100 mm and a thickness at 500 ° C of 3 mm Pl = plate Pa = packing Fo = foil The product was used in the following manner: The refractory sealing material according to the invention in the form of the plates of Examples 1, 2 and 4 was on one with an aqueous Waterglass solution moistened liner on a seam portion of these magnesia liner panels a 30 ton tundish for continuous steel casting glued on, and the sealing material was preheated to 900 OC. After the melt was poured in four continuous casting processes from a ladle of 200 t the intermediate container was removed for a repair operation. At this time the states of wear of the lining panels were observed, and the influence became inspected for the permanent lining material in the lower section after every 10 cycles, the molten steel was found to be the lower permanent liner material not eroded at all. Comparative example 1 was also used after 10 cycles the seal with which the seam of a lining material with a magnesia cement had been replenished, inspected.

The results in all cases were such that the hem section or Joint section was eroded, allowing repair of the lower permanent lining material was required.

Furthermore, a ladle of 200 t above the A bubble-shaped flow of argon through a porous intermediate container Plug carried out, a packing plate of Example 3 for sealing the Bottom surface of the porous plug was used, and the porous plug was replaced, although the sealing section hardly cracked even after eight regular batches was. In Comparative Example 2, the composition was as in Comparative Example 1 mixed and kneaded and used as a mortar before molding an object from this mass of Comparative Example 1 on the connection at the bottom, which is with a porous plug was provided, applied, but a more than 5 times longer working time was required. The inspection result was almost unchanged.

Claims (5)

Claims lo Fireproof sealing material with mixed values from 50 to 90% by weight of refractory fillers with a particle size of less than 0.1 mm, based on the dry content, 1 to 10% by weight of fibrous refractory materials and 9 to 50% by weight plasticizer, the mixture being in the form of sheets or foils have been deformed after the addition of a suitable amount of liquid is. 2. Refractory sealing material according to claim 1, characterized in that that the refractory filler used is silicon dioxide, quartz sand, peridotite, chamotte, Aluminum oxide, corundum, mullite, magnesia, spinel, chromium oxide, zirconium dioxide, titanium dioxide, Zinc oxide, brick, slag and the like or a mixture thereof. 3. Refractory sealing material according to claim 1, characterized in that that as a fireproof, fibrous material, asbestos, rock wool, slag wool, Glass wool, keolin fibers, aluminum oxide fibers, magnesium oxide fibers, silicon carbide fibers, Contains carbon fibers and the like or a mixture thereof. 4. Refractory sealing material according to claim 1, characterized in that that it is used as a plasticizer alkali metal chlorides, alkaline earth metal chlorides, water-soluble phosphates, clay, kaolin, bentonite, or starch, dextrin, glue, rubber arabic, water-soluble resins, solvent-soluble resins, insoluble resins, gum or high polymer compounds including petroleum products and products of Contains dry distillation of coal or a mixture thereof. 5. Refractory sealing material according to claim 1, characterized in that that in its production as a liquid water, alcohols, esters, ketones or Hydrocarbons or a mixture thereof has been used as a liquid.