JPS61245951A - Nozzle for casting - Google Patents

Abstract

PURPOSE:To provide a nozzle for continuous casting which reduces an initial cost and prevents the temp. drop of a molten steel by combining integrally a forming part by a rubber press and a castable casting part. CONSTITUTION:A base body A including the contact surface with a molten steel or slag of the nozzle for continuous casting is constituted of an individual material of alumina-graphite type, zirconia-graphite type or magnesia-graphite type refractories which are molded by the rubber press or the composite body thereof. The non-contact part B of said nozzle is constituted of castable refractories. The initial cost is thereby reduced and the solidification and alumina deposition by the temp. drop of the molten steel during use are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a continuous casting nozzle that is formed by integrally combining a molded part by a rubber press and a castable cast part.

[Conventional technology]

Conventional continuous casting nozzles are generally composed of an alumina-graphite material or a slag line,
A composite material is used in which the powder line portion is reinforced with zirconia-graphite material, and the outer periphery is processed.

Some parts of the immersed part are left unprocessed, but the flange part has to be processed to accommodate hardware, etc.

[Problem that the invention seeks to solve]

Products that are entirely made of the above-mentioned alumina-graphite single material are formed to be slightly thicker than the special molding drawing dimensions using a rubber press in order to improve finishing accuracy, and then processed and finished, resulting in waste during manufacturing. is large. Alumina-graphite materials are generally expensive, and there is waste due to the use of large amounts of such materials and waste due to processing loss.

In addition, in terms of material, in order to prevent cranking during preheating and during use, a large amount of graphite is used, which has high thermal conductivity, making it easier for the heat of molten steel to dissipate from the nozzle surface during use. , problems such as molten steel solidification and alumina precipitation in the nozzle occur. Furthermore, since there is a large amount of conduction to a portion of the holder, there is also the disadvantage that the holder is easily damaged.

An object of the present invention is to solve the problems of the conventional continuous casting nozzle described above, and to provide a continuous casting nozzle that reduces raw material costs, eliminates raw material loss, and has excellent heat insulation properties.

[Means for solving problems]

The present invention relates to a slug line, with reference to the accompanying drawings.

The nozzle base A including the powder line portion is made of a conventional refractory material such as alumina-graphite, zirconia-graphite, magnesia-graphite, etc. molded by a rubber press, and the portion excluding the slag line and powder line portion, that is, the non- The contact portion B is made of castable material.

As the material constituting the nozzle base A including the slag line and powder line portions, those shown in Table 1 can be used.

In addition, the castable that constitutes the non-contact part B is as follows:
Those shown in Table 2 can be used.

In addition, when forming the nozzle, the base A is molded using a normal rubber press in a mold having a shape excluding the non-contact portion B, and then the slag line of the base A,
Castable is cast into the non-contact portion B excluding the powder line portion to create an integrated structure.

As a result, the non-contact part B can be made of a material that is less expensive than the base body A, and since the flange part, which requires precision, is castable, there is no need for machining. The insulation properties of the constituent materials are
Part A has a thermal conductivity of 12 kcal/m, hr,'e, whereas it has a thermal conductivity of only 12 kcal/m, hr,'t:
Therefore, it is possible to prevent the temperature of molten steel during use from decreasing, thereby preventing solidification or precipitation of alumina.

Hereinafter, the structure and effects of the nozzle of the present invention will be specifically explained using Examples.

〔Example〕

The nozzle shown in the figure was constructed by combining the material for part A shown in Table 1 and the material for part 8 shown in Table 2. Tables 3 and 4 show the combinations and the characteristics of the nozzles obtained by the combinations.

Table 1 Materials and quality examples of part A component Table 2 Materials and quality examples of part B component Table 3 Combination examples Table 4 Combination examples [Effects of the invention] The nozzle according to the present invention can have the following effects. can.

B. Reducing raw material costs by using multiple layers with non-additive exhaust staples.

The temperature of molten steel during use decreases due to a decrease in the thermal conductivity of the part where the B member (castable) is used, thereby preventing solidification or alumina precipitation.

C. Significantly improved neck strength by making it castable.

2. Prevention of strength deterioration due to oxidation of the neck due to less coating surface of antioxidant.

[Brief explanation of drawings]

The attached drawings are diagrams showing an example of the structure of a nozzle according to the present invention.

Claims (1)

[Claims] 1. The base body including the contact surface with molten steel or slag is composed of a single or composite material of rubber press-molded alumina-graphite, zirconia-graphite, or magnesia-graphite refractory, and the non-contact part is castable refractory. A casting nozzle characterized by being made of a material.