DE1090389B - Compound for filling block molds on molds - Google Patents

Description

GERMAN

The invention relates to the composition of a compound for lining block-shaped attachments Permanent molds and other casting molds.

According to the invention, said mass consists at least partially made of crushed, granular or lumpy aerated concrete, possibly with admixture of flammable or exothermic substances, is solidified with the help of a binder, so * that In turn, spaces remain between the granular material to increase the gas permeability.

It is known in normal concrete for high-rise buildings to replace the usual additions of sand and stone material with blast furnace slag. So composite However, concrete is not suitable for block form attachments, as that is created by rapid heating Water vapor would partially penetrate into the steel bath and burst the concrete body. That Water originates as. Water of crystallization from the cement and can because of the low porosity of the concrete does not escape quickly enough as steam.

The mass preferably contains 25 to 65% aerated concrete. According to a further idea of the invention, the combustible admixtures consist of rice chaff, Chaff, sawdust and similar material. As an exothermic substance, for. B. added aluminum powder be.

Water glass or sulphite waste liquor, for example, serve as binding agents. At the one facing the mold On the inside of the lining, the block-shaped attachment expediently has a further layer of sand, powdery Dolomite or limestone. The purpose of the layer is to keep the molten metal against carburization through the combustion gases; the pouring hood to protect.

The use of the porous concrete gives the block top great strength and at the same time a very good insulating properties, low specific weight and, if the porous concrete in large percentage is present, has a high melting point. When the binder for the crushed aerated concrete material consists of water glass, it is often expedient after or during the molding of the block form attachment elements To add carbonic acid or carbonic acid-releasing substances, which react with the water glass Make the product, especially its surface, hard and firm.

Instead of making the block molding attachment in one or more parts in molds and then putting these parts in to assemble the mold, the material can also be placed directly into the mold using an if necessary removable ramming form. Both when ramming as with the previous one Production of the block form attachment, it is advantageous to give the block form attachment a downwardly tapered Compound for lining block form attachments on molds

Applicant: Enn Vallak, Geneva (Switzerland)

Representative: Dr. R. Bauer and Dipl.-Ing. H. Hubbuch,

Patent attorneys, Pforzheim, Westliche KaTl-Friedrich-Str. 31

Claimed priority: Sweden, August 27, 1956

Bertil Helmer Allvin, Gösta Hugo Cedervall and Hans Friedrich Uibopuu,

Grythyttan (Sweden) have been named as the inventor

To give shape, whereby the transition part of the casting from the upper part is more uniform, what for later rolling is favorable.

It is important that the grain size of the material or mixture of materials is correct Manner is adjusted so that the desired gas permeability is obtained. The Grain sizes kept within a narrow range, e.g. B. between 0 and 8 mm with the main amount about 2 to 5 mm.

As examples of various compositions of the block molding material according to the invention can serve the following:

mixture
No.

Mixing ratio in liters

Coke powder
0 to 4 mm
Grain size

5 to 10
10 to 15
15 to 20
20 to 25
25 to 30
30 to 35

Aerated concrete with a grain size of 0 to 5 mm

55 to 50 50 to 45 45 to 40 40 to 35 35 to 30 30 to 25

Fine sawdust

30 to 60 30 to 60 30 to 60 30 to 60 30 to 60 30 to 60

The materials are carefully mixed, and waterglass or other binding agent is applied on top

009 610/343

added and mixed in. The proportion of aerated concrete can be expressed in percent by volume z. B. between 100 and 10%, expediently between 25 and 65%. In the table above, the percentage of coke can also be whole or partially replaced by sand.

According to the invention, the term "aerated concrete" also includes other hydraulically hardening compounds, such as z. B. lime, gypsum cd. The like. Which are appropriately porous, d. H. gas-permeable, have been made. as Means to make you po'rös. the mass can: also mentioned resin soap (a foaming agent) dissolved in water will.

According to one embodiment of the invention, rice husks or rice chaff or other combustible materials are used Material used to make the product porous. Rice chaff is cheap and has a proportion light weight. When using rice chaff, straw or other flammable particles, z. B. sawdust, they are with cement or other hydraulic binder, sand or other mineral components as well as water mixed, after which the casting hood plates from this Mixture are poured, so that one gas-permeable due to the addition of combustible particles Product received. When using the casting hood plates, the mold burns during casting the combustible material and leaves cells; or small voids in the concrete mass. The addition to flammable particles can come from. 0.75 to 85 percent by weight of the total amount of the dry mixture fluctuate before adding the water. As an example, a mixture of around 50 percent by volume rice chaff, 20 percent by volume of sand or gravel and 30 percent by volume of cement are mentioned, which is about 6.25 percent by weight Rice chaff, 37.5 percent by weight sand or gravel and 56.25 percent by weight cement. The mixture results in a product that has good gas-permeable (porous) properties, so that the when the combustible components of the casting hood material are burnt during the casting of the metal Gases produced in the mold can escape through the walls of the casting hood without the molten Metal needs to be flowed through.

Claims (4)

P A T E N T A N S P K Ü C H E: 1. Compound for lining of Blcckformaufsatz on chill molds and other casting molds that at least partially consists of crushed, granular or lumpy aerated concrete, which, if necessary with the admixture of flammable or exothermic substances, with the help of a binder like this is solidified that between the granular material in turn gaps to increase the gas permeability stay·. ■ 2. Composition for lining according to claim 1, characterized by a proportion of 25 to 65 ⁰ Zo crushed aerated concrete / '- ■ 3. mass for lining, according to claim 1 and 2, characterized by an admixture of combustible ■ material such as rice chaff, chaff, sawdust or the like. "■: 4. Lining of block-shaped attachments according to Claim 1 to 3, characterized in that on the inside of the equipment facing the casting mold feeding another layer of sand, powdery Dolomite or limestone is applied. Considered publications:
U.S. Patent No. 1,547,787. © 009 610/343 9.60