DE2260403C3 - Process for the production of linings for risers, block heads or thermal hoods - Google Patents

Description

described and serves to increase or 45 tion of oxidizable metals. Block head located molten metal long If the starting material is oxidizable material

to keep enough liquid that during the solidification of the casting, at which a shrinkage occurs, hot molten metal can be replenished.

So far, such linings have been made by that with the binder mixed materials in the green state, for example, formed into a sleeve and in a corresponding one Oven has dried. The binding of these sleeves, however, takes a relatively long time.

The invention was now based on the object of creating a method with which linings for risers, block heads or heating hoods for metal casting can be produced more quickly.

According to the invention, the object is achieved in that one before adding the rest Components a combustible material with a flash point below 50 ° C is added to the binder; the crowd forms and ignites the combustible material <> 5

The advantage of the method according to the invention is that the linings by the presence of the combustible material can be cured quickly and contains an oxidizing agent, then this is easily generates smoke, dust or gas, causing the molten material to billow. Man this can be avoided by using a porous refractory material in the lining in this case incorporated.

The invention is illustrated in more detail by the following example.

The following mixture is produced.

aluminum

Iron (III) oxide

Potassium nitrate

Sodium fluoride

Expanded obsidian

Quartz sand

Phenol / formaldehyde synthetic resin

First, the phenol / formaldehyde resin is in a sufficient amount of methyl alcohol, which as combustible material is used, dissolved. Then the

Weight percent
15th
10

40 20th 10

si

Particles of the expanded obsidian are mixed with this solution. The remainder of the above components are _then worked on. By introducing the mixture * into a corresponding mold, green pods with an inside diameter of UO mm and a height of Oram and a wall thickness of 2a are now produced. After removal from the mold, the methyl alcohol is set on fire, thereby solidifying and drying the pods. Production "*" for the * pods is: moderately short compared to the well-known process of solidification and drying in one

vÄatenrergSttC corresponding [J mostly already with a load of 45 k _fe cm

Claims (4)

Patent claims: 1. Procedure zui.i, production of linings for risers, block heads or heating hoods for metal casting, especially of iron and steel a moldable mixture consisting of a thermosetting plastic as a binder, insulating and / or exothermic fillers, which after molding by supplying heat is hardened, characterized in that before the other ingredients are mixed in A combustible material with a flash point below 50 ° C is added to the binder, the mass formed and the combustible material is set on fire. 2. The method according to claim I _1, characterized in that a phenol / formaldehyde synthetic resin, urea / formaldehyde synthetic resin, silicone synthetic resin or furan synthetic resin is used as a binder. 3. The method according to claim 1 or 2, characterized in that gasoline as the combustible material, Methyl alcohol, ethyl alcohol, ligroin or mineral spirit is used. 4. The method according to claim 1, 2 or 3, characterized in that as insulating and / or exothermic filler a mixture of an oxidizable metal, an oxidizing agent and a porous refractory material is used. no · ,. This can make manufacturing significant can be done faster and at lower cost. According to the invention, a phenol / formaldehyde synthetic resin, urea / Formaldehyde resin, silicone resin or furan resin are used. It is beneficial to this To dissolve synthetic resin binders in a solvent or to dilute them with the help of a solvent. ίο You can advantageously use a flammable solvent, such as. B. gasoline, methyl alcohol, Ethyl alcohol, ligroin or mineral spirits. As insulating and / or exothermic fillers, refractory materials, oxidizable metals in Combination with oxidizing agents, fiber materials, carbonaceous materials; Fluorides and the like, Find use. Examples of refractory materials are non-porous materials such as e.g. B. Quartz sand, magnesium oxide, Alumina, dolomite, magnesite, limestone, fireclay, carborundum, etc., and porous materials such as. B. Diatomaceous earth, lapille, expanded vermiculite, expanded slate, expanded obsidian, expanded Perlite, expanded pitch stone, etc. Examples of oxidizable metals that can be used are aluminum, Magnesium, aluminum / magnesium alloys, calcium / silicon alloys and iron / silicon alloys. These metals react exothermically with oxidizing agents. Examples of oxidizing agents are metal oxides, for example iron (II) oxide, iron (III) oxide, Triiron tetroxide, manganese dioxide, bromine oxide, etc., as well as nitrates, for example potassium nitrate, sodium nitrate, Barium nitrate, etc. Examples of fiber materials are asbestos, Steinwol-Ie, Slag wool, glass wool and other inorganic fibers. Organic fibers can also be used become, such as B. paper pulp, wood pulp, cellulosic materials, soft made by beating paper sawdust, etc. Only smaller amounts of the latter should be used. Examples of carbonaceous materials are coke, charcoal, charcoal, graphite, etc. The addition of fluorides, such as. B. sodium or calcium fluoride, or cryolite, accelerates the oxidation The invention relates to a method for producing linings for risers, block heads or Warming hoods for metal casting, in particular iron and steel, made from a malleable mixture consisting of a thermosetting plastic as a binding agent, insulating and / or exothermic fillers, which is hardened by applying heat after molding. Such a lining is in DT-OS 14 33 934