JPS6141874B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention applies to the gap between the steel shell and bricks of a converter, etc., the gap between a stave cooler (cooling box) and the steel shell, and the gap between bricks such as a corner of a converter (hereinafter collectively referred to as a converter, etc.). Self-hardening refractory compositions used for filling gaps (referred to as gaps) have particularly high adhesion to the surface of iron parts, do not shrink or change before and after curing, and are stable regardless of the type of refractory raw material. The purpose of the present invention is to provide a fire-resistant composition that has excellent self-hardening properties. Conventionally, attempts have been made to use self-hardening fireproof compositions containing phenolic resin as a binder for the above-mentioned applications. However, when these compositions are filled into gaps such as between steel shells and bricks, or between stave cooler steel shells, their adhesion to the steel shells is not necessarily sufficient;
When subjected to mechanical shock during operation, it often peeled off from the surface of the steel member. In addition, when these compositions are filled into gaps by pouring or stamping, micro-voids are generated at the interface between the steel shell and the filler due to shrinkage after curing, resulting in problems such as the inability to fully demonstrate its function as a filler. It was hot. Furthermore, self-hardening monolithic refractories using phenolic resin as a binder generally use a resol-type initial condensate and an acid catalyst such as para-toluenesulfonic acid or sulfuric acid as a curing accelerator; When magnesia, dolomite, etc. are used, the reaction between the curing accelerator and these raw materials proceeds preferentially, so the curing of the phenolic resin is significantly inhibited, and a sufficient cured product may not be obtained, or the cured product may have extremely low strength. There were problems such as only being able to obtain the body. Furthermore, since the metal components contained in the refractory raw material, such as iron, react with the curing accelerator, the curing rate fluctuates extremely, which poses a practical problem. The present invention has solved these problems, and the composition of the present invention contains 100 parts by weight of at least one refractory raw material selected from magnesia, dolomite, and carbon, a liquid epoxy resin, and a curing agent that has a curing effect at room temperature. It is made of a self-hardening fireproof composition for filling gaps in converters, etc., which is made of 15 to 40 parts by weight of a binder composed of polyamide and polyamines, has high adhesion to the surface of iron parts, and has no shrinkage change before and after curing. And regardless of the type of refractory raw material,
It has stable self-hardening properties. The liquid epoxy resins used in the present invention include bisphenol epoxy resins obtained by the reaction of bisphenol A and epichlorohydrin, bisphenol epoxy resins obtained by the reaction of bisphenol F and epichlorohydrin, and other resins. Ring compound-based epoxy resins, epoxy-containing pinyl polymers, etc. are used. The curing agent used in the present invention is appropriately selected from polyamides and polyamines that have a curing effect at room temperature depending on the required curing time. Specifically, polyamines such as diethylenetriamine, triethylenetetramine, and tetraethylenepentamine, and polyamides obtained by reacting dimer acid with diethylenetriamine and triethylenetetramine are preferably used. The binder of the fireproof composition is composed of a liquid epoxy resin and a curing agent, and the amount thereof is equimolar to the content of the liquid epoxy group. In the self-hardening refractory composition of the present invention, the refractory raw material is 1 selected from magnesia, dolomite, and carbon.
It can be used as a species or as a mixture of two or more species. The blending ratio of the refractory raw material and the binder is 15 to 40 parts by weight per 100 parts by weight of the refractory raw material. When the amount of binder is less than 15 parts by weight, the strength of the cured product after filling is low and the adhesion to the steel shell is low, which poses a practical problem. In addition, if the amount of binder exceeds 40 parts by weight, when used in areas where the temperature of the filled part is 300°C or higher, the resin in the cured product will thermally decompose and volatilize, resulting in increased porosity and reduced strength. There is. The liquid epoxy resin used for the binder may be used alone or in combination with other resins. In particular, when filling a site with a temperature of 300°C or higher, it is preferable to use it in combination with a resol type phenolic resin. Among them, bisphenol liquid epoxy resin and liquid resol type phenol resin are mutually compatible and are preferably used in combination. In this case, the combined ratio of liquid epoxy resin and liquid resol type phenolic resin is 8/2 to 2/8.
is preferable, and if it exceeds 8/2, the porosity during heat reception will increase and the strength will decrease. Moreover, when it is less than 2/8, the adhesion to the steel shell is small and the shrinkage rate before and after curing is large, causing problems such as the formation of voids between the filler and the steel shell. In the case of a binder made by adding a curing agent made of polyamide or polyamine to a mixture of liquid epoxy resin and liquid resol resin, 15 parts by weight per 100 parts by weight of the refractory raw material is the same as when liquid epoxy resin is used alone.
~40 parts by weight are used. The refractory composition of the present invention is prepared by adding a liquid epoxy resin and a curing agent to a refractory raw material, kneading it in a conventional kneader, and immediately after kneading, it is poured or stamped. In terms of adhesion and adhesion to the steel shell, pouring is preferred. Next, the present invention will be explained with reference to Examples. Example 1, Comparative Example 1 Immediately after kneading, a refractory composition of magnesia and carbon-based refractory raw materials shown in Table 1 was poured into the gap between the steel shell and the bricks of a converter. For comparison, a fireproof composition containing a conventional phenolic resin and an acid curing accelerator as a binder was also tested. The results are shown in Table 1.

【table】

[Table] Example 2, Comparative Example 2 In the gap between the steel shell and bricks of a converter at about 350℃,
A self-hardening refractory composition was prepared by kneading a refractory raw material consisting of only magnesia, a binder consisting of a liquid epoxy resin, a liquid resol type phenol resin, and a hardening agent, and immediately poured into the composition.

[Table] As shown in the examples above, the present invention has excellent adhesion to iron and bricks, and the change in line during use is extremely small, so it can fully function as a filler. be. In addition, since the adhesive strength with the MgO-C bricks is strong, it was possible to prevent the wear bricks from coming off and falling off at the constriction part during operation of the converter, especially when tilting, resulting in good results.

Claims (1)

[Claims] 1 Consists of 100 parts by weight of at least one refractory raw material selected from magnesia, dolomite, and carbon, and 15 to 40 parts by weight of a binder composed of liquid epoxy resin and polyamide or polyamines that have a curing action at room temperature as a curing agent. Self-hardening refractory composition for filling gaps in converters, etc.