DE1483617A1 - Insulating board for heat hoods - Google Patents

Description

Dr. Ing. E. BERKENFELD, patent attorney, COLOGNE, Univer »ltatiitro6 · 31

U83617

"""if. ν «. I6.9.iy6fj CS _Nqm . , ^ ₁₁₁₁ Oglebay Norton Company

Insulating board for heating hoods

The invention relates to a hard-to-melt material for use for heating hoods and in particular a plate or board for such heating hoods that come into contact with molten metal, which is poured into a mold to which the heating hood is connected.

Known heating hoods and especially panels or plates for such hoods are made of a material consisting of organic and inorganic fibrous materials mixed with a granular, difficult to melt material, and a binder. These known insulation panels or plates develop Oasblasen when they come into contact with molten metal, which is what the metal has been referred to, at least in part, to flow through the molten metal and cause eo with a "boiling". This boiling can cause the metal to splash and spark

cause spray, which means a danger to the pouring column. Furthermore, hydrogen and oxygen can be collected through the pouring attachment metal, causing harmful metallurgical effects.

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The invention relates to the solution to this boiling problem. It was found that by eliminating or greatly reducing the organic fibrous material content in the insulating panel and using an asbestos fiber, which has a low water content in the material, and a component of the board represents, the boiling of the molten metal is largely reduced. It also allows the use of an asbestos material Because of its low water content, the use of a relatively fine-grained filler material that makes a table with good Provides insulation capabilities.

The invention therefore relates to a new and improved heating hood, which is made of a material that develops a tiny amount of oasis bubbles when it comes into contact with molten metal comes and thereby reduces the amount of molten metal boiling, and has good insulating properties, strength and has elasticity.

The invention also relates to a new and improved thermal hood insulation panel or panel, the panel being made of a material containing asbestos with a low water content and which develops a relatively small amount of gas bubbles when it comes in contact with molten metal and wherein the material Contains a small, if any, amount of organic fibrous material.

The invention also relates to a new and improved thermal insulation panel or plate made from a material called alosit, a relatively fine-grained, difficult-to- melt filler

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and a suitable binder which includes an insulating sheet or Plate with good thermal insulation properties, sufficient strength and yields elasticity, and one of the smallest amounts of GaS ^ is developed when the plate comes into contact with molten metal comes.

The invention also relates to a new and improved warming hood! solierplat te, composed of 79-90 parts by weight of granular, heavy refractory filler, 5-10 weight parts of organic binder and 5-10 parts by weight of asbestos with a water content of less than 6%..

The invention also relates to a new and improved heat hood insulating plate, composed of 79-90 parts by weight of 200 mesh quartz sand, 5-10 parts by weight of organic binder, 5-10 parts by weight of amosite and about one part by weight of organic fibrous material.

Further advantages of the preferred embodiment of the invention result from the following description based on the drawing. It show: ■.

Fig. 1 is a side view of a heating hood, partially in Cut,

Fig. 2 shows a partial version of a modified heating hood, Pig. ' 5 a partial view of another bearded warming hood.

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The invention relates to an improved warming hood, and more particularly an improved panel for use in a heated hood. As is well known, heat hoods are used in conjunction used with molds to have molten metal in stock above the mold with which blowholes are charged

Heating hoods,

the while the metal cools in the mold that is on the top Store at the end of the mold, have a central opening through which the molten metal is poured into the mold. That molten metal is also poured to fill the heat hood. The warming hood consists of a suitable insulation, -um to have some metal in the molten state in the heating hood, with which the blowhole cavity is charged, while the metal solidified in the mold.

Heat hoods are produced in various designs; Pig. I. For example, FIG. 4 shows a preferred embodiment of the invention, according to which a heat hood 10 is placed in the upper end of a mold 11 rests. The heating hood 10 has a central opening through which the molten metal is poured into the mold. The warming hood 10 has a metal frame 12 of conventional design with a upper part IjJ and a lower part 14, which in a suitable manner are connected to each other. The metal housing 12 has a putter 17 * which is made of a hard, dense, high-temperature-resistant Firebrick or an equivalent castablex, fire- • consists of solid material that forms a putter or a support for the highly refractory .. insulating board. The putter is semi-permanent; it can be used for multiple casting operations.

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An insulation lies on the putter 17, which consists of individual insulation

25th

panels or plates that are in a suitable position in the heating hood, the putter 17 superimposed, are attached, which supports the panels 25 from behind and serves as an abutment of the panels. That The upper end of the panels 25 is substantially flush with the upper side of the upper shell 26 of the metal frame 12, whereas the lower end Ends of the panels 25 in a recess 27 of a floor ring 28 are supported.

When the molten metal through the central opening of the heating hood is poured, the molten metal comes with the insulating panels 25 in touch. If the insulation panels, the great Mengac known organic, fibrous materials that come into contact with the gcsciiiTiolzenen metal, develop the materials in the panels gas bubbles which flow through the molten metal and thus cause the molten metal to "boil". According to the invention, the refractory insulating panels are made of a material that allows development which reduces gas bubbles to a minimum when in contact with molten metal, and thus the boiling of the molten metal reduced to a minimum.

The material from which the panels are made contains a granular, difficult-to-melt filler, a binder and an inorganic fiber asbestos that has a relatively low bound water content. The granular, so hard-to-melt one The filler preferably consists of relatively fine sand, for example 200 mesh quartz sand, i.e. a quartz sand of which the

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Main part goes through a 200-mesh sieve. Others grainy, heavy Fusible fillers can also be used, such as diatomaceous earth, magnesia, clay or forsterite. The binder may be any known one such as phenolic resin or an organic resin. It can also be a small amount of organic, fibrous Materials are added to the mixture, such as ground wood fiber, Cardboard shavings or paper pulp or a mixture of these.

The asbestos molding material has a bound water content of less than 6 #. Crocidolite, anthopfryllite, tremolite or amosite asbestos can be used, all of which have a bound water content of less than 6 % . These materials also have low weight loss on combustion. Amosite asbestos is preferred because of its fiber strength and availability. Amosite asbestos contains a small amount of water, which is less than about 6 % by weight, and has an extremely low weight loss on incineration compared to other asbestos which have a high water content and an even higher loss on incineration. The amosite asbestos has a bundle-like fiber structure with pores and cavities and an orthorombic crystal structure. The amosite asbestos also has a sufficient fiber length and tear resistance? Properties that give panels the required strength and elasticity for heating hoods.

The following table shows the compositions of boards according to the invention.

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Ingredients parts by weight preferred

- parts by weight

granular, difficult-to-melt filler 79 - 90 86 - 87

Binder 5 - 10 6

Asbestos with less than

6 # water content 5-10 8

organic fiber material

less than 2 0-1

As mentioned above, the use of the above materials in the manufacture of an insulating panel for heat hoods results in a light weight and the development of gas bubbles on contact with molten metal is reduced to a minimum; the panels also show a relatively low weight loss when in contact with tjjeschinolem metal compared to other known panels which contain substantial amounts of organic fiber material. Experiments have shown that the weight loss of the panels made from the above material is 5-6 % compared to 11 % for the conventional panels. In addition, panels made in accordance with the invention have little or no organic fiber material in the mixture and so significantly reduce or eliminate the gas bubbles developed by organic fiber materials. The insulating ability of the fusible boards according to the invention is good because a relatively fine, difficult-to-melt filler is added. The use of a relatively fine, difficult-to-melt filler results in many small air pockets in the board and leads to better insulation than if a coarser filler is used.

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• is det. Although the Lufttasohen are relatively small, they, however, are sufficient ^1, to give a sufficient porosity so that could escape during the contact of the panel with the molten metal Ga.sblasen developed through the panel and not by the molten metal. Furthermore, the bundle-like fiber structure of the amosity best results in air pockets in the board, which contribute to the escape of the gas bubbles through the boards.

To the. The granular, difficult-to-melt filler, amosite asbestos and the binder are used in the manufacture of the panels in one common; Mix the kettle with a suitable amount of water in a suitable ratio. The amount of water can be any, but 1 ^ 5000 parts by weight proved to be satisfactory. The asbestos is added to the water first. The binder is then added to the mixture and finally, after the asbestos and the binder have sufficiently distributed ¹ in the mixture, the granular, difficult-to-melt filler is added. The mixing time must be sufficient to ensure a suitable, uniform mixture! in general, half an hour was found to be satisfactory. · *

After mixing, the mixture turns into tablets

deformed a suitable casting process. The panels are in the desired shape and strength for the particular use for which they are intended, deformed and then become self-supporting Dried panels with sides practically parallel. This turned out to be a suitable casting process Pour the mixture into a surface covered with a wire net

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sole board and the application of vacuum to the main part of the water to withdraw. After the deformation, the panels are dried. The drying temperatures and times can vary but they must be chosen so that the temperature at which the amositasbestos can be decomposed is not exceeded. The plates are left to dry in an oven for two hours given at 204 ° C, then the temperature is decreased to 149 ° C for one hour.

The Arnosit absorbs some of the water during the process

Amosits

the pores and spaces in the bundle-like fiber of the fills. When the "water" forms and dries the plate is withdrawn, the water is removed from these spaces and the spaces or pores remain and form air pockets throughout the plate. These pockets of air, it is assumed, help that the plate turns out to be a good insulator and the escape of gas bubbles through the plate is made possible by them.

Insulating panels or plates according to the invention can be used in any heat hood of any configuration. According to FIG. 2 of the drawing, the panels 30 are stored in the heating hood, ie they are supported by a metal part 32 of the heating hood. This part 32 is arranged in a suitable manner and with. connected to the upper part 33 of the housing of the heating hood. The panels 30 rest on the surface 3 ^ of the part 32. A floor 35 is supported at the lower end of the part 32. The ring has a recess 36 in which the lower end of the panel 30 is supported.

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According to FIG. 3, panels 40 are arranged in the upper end of a mold 41 the upper edges of the panels are essentially with the upper ends of the mold 4l flush. Accordingly, extend the panels in the mold 4l. The panels 40 form the heat hood and thus a putter in the upper end of the mold 4l. The panels 40 can be held in the upper end of the mold with clips 42 that hold the mold 41 and the panels 40 together, and the hold the panels in position in the upper end of the mold. The Ta-

* fine 40 can also be used in the upper end of the mold by means of suitable, not shown, tapered, wedge-shaped angle pieces are held. These can go down to the corners of the mold are driven between the adjacent side panel pieces and wedge the panels 40 into firm contact with the inner walls the ingot mold 4l so that the panels are firmly held in the upper end of the mold 4l.

Claims

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Claims (1)

H83617 - ■ Claims 1, Insulating panel particularly suitable for heating hoods, which contains a granular, difficult-to-melt filler and a binding agent, characterized by an asbestos molded material which has a water content of less than 6 % . 2. Board according to claim 1, characterized in that the Asbestos molding material has amosite » j5. Board according to claim 1, characterized in that the Asbestos molded material amosite in bundle-like fiber form, crocidolite, Has anthophyllite or trmolite. k. Panel according to claims 1, 2 or 3 * characterized by 79-90 parts by weight of filler, 5-10 parts by weight of asbestos molding material and 5-10 parts by weight of binder. . 5. Panel according to any one of the preceding claims, characterized by a small amount of organic fibrous material. 6. Panel according to claim 5, characterized by 1 wt. % ■ organic fibrous material. ' 909882/0573 BAD OnW.NAU. J HOOO I / Λ table according to irr; e..J ^r iiaü.: I of the preceding claims, i.'ii'ii'c ;. ; jc .-- Oii «-z iIc! Ki-3t that the filler contains Q, uarzsand, the ^ u.-j.i j in.20C -; - lasclien-SieL jeht. ο. Garrison for the production of an insulating panel, j ^ .- ierm- zeic.mot a.:i'(.m /.> -. ^f .i0 parts by weight iiüni ^ e:., sc.-iwer schirielzbarari ffii.:., j - IO parts by weight Arno sit uua 5 - 10 Gc-v.Teilo one • _i. Process for the production of a ./är.nehaube, in which ... VJ - 'JO Oov /. Parts of a kor.iijan, difficult to melt filler, 1> - 10 Ge -,?. Parts of a r3iiidemmittel and water mixed ioeht ν.'3ΐ ·: 1οη, because by C2 ^icenn zeiclinetj that ^ - 10 parts of an asbestos form-; a material with an asbestos form-; a material with an under 6, j '. " substantially parallel sides is pre-formed. 10. The method according to claim 9, characterized in, let one part by weight of an organic fiber! ^ e .: "materials in the Mixture can be added. BATH 909882/0573 - 12 -