Crucible is a kind of refractory graphite crucible, which is made with different types of clinker and is mainly used for smelting special alloy steel, melting nonferrous metal and its alloy. The graphite crucible is a component of refractory material in terms of its properties and USES.
Crucible can be divided into graphite crucible, clay crucible and metal crucible three categories. In the graphite crucible, there are three kinds of ordinary graphite crucible, different graphite crucible and high purity graphite crucible. Different types of graphite crucible, due to different performance, use and use conditions, used materials, production methods, technology and product models and specifications are also different.
The main raw material of graphite crucible is crystalline natural graphite. Therefore, it maintains the original physical and chemical properties of natural graphite.
That is, it has good thermal conductivity and high temperature resistance. In the process of high temperature use, the thermal expansion coefficient is small, and it has certain strain resistance performance to the rapid heating and cooling. Corrosion resistance graphite crucible has strong corrosion-resistance to acid and alkaline solution and excellent chemical stability.
There are many types and specifications of crucible, and it is not restricted by the production scale, batch size and the variety of smelting substances in its application. It can be arbitrarily selected, with strong applicability and can guarantee the purity of the smelted substances.
Cheap graphite crucible, due to the above excellent performance, is widely used in metallurgy, casting, machinery, chemical and other industrial sectors, alloy tool steel smelting and non-ferrous metal and alloy smelting. And has the better technical economic effect.
The types of crucible can be roughly divided into three categories: the first type of copper crucible, its size "no."; The second type is copper alloy crucible, with a special round size of 100, a round size of 100, the third type of steelmaking crucible, with a size of 100.
Crucible size, usually expressed as a serial size, crucible no. 1 has a capacity to melt 1000g of brass and a weight of 180g. The melting amount of crucible in melting different metals or alloys can be calculated by multiplying the density specification number of crucible by the corresponding metal and alloy coefficient.
The production materials of crucible can be classified into three types. One is crystalline natural graphite, the other is the plasticity of fire resistance clay, three is calcined hard kaolin skeleton clinker. In recent years, high temperature resistant synthetic materials such as silicon carbide, alumina emery and ferrosilicon are used to make skeleton clinker of crucible. The clinker has remarkable effect on the quality of crucible, the density of crucible and the mechanical strength of crucible.
Crucible molding, there are three methods, the more primitive ancient molding method is hand molding. The second is spin molding and the third is press molding.
The production of domestic graphite crucible has reached or even exceeded that of imported crucible, especially the largest production enterprise of graphite crucible in Yangtze river delta region. The graphite crucible produced by jinda crucible factory as a representative of domestic crucible has the following characteristics:
1. The high density of graphite crucible makes the crucible have the best thermal conductivity, and its thermal conductivity effect is obviously better than other imported crucible;
2. The graphite crucible has special glaze layer and dense molding material on the surface, which greatly improves the corrosion resistance of the product and prolongs its service life;
3. The graphite components in the graphite crucible are all natural graphite, with excellent thermal conductivity. The graphite crucible should not be placed on a cold metal surface immediately after heating to prevent it from cracking due to sharp cooling. The melting of many kinds of alloys in small quantities is most suitable for the use of crucible. To change the type of alloy, just exchange the graphite crucible. Other melting methods, such as reverberatory furnace and non-crucible induction furnace, are suitable for a large amount of melting of a single alloy. If the type of melting alloy is changed, if the lined refractory is not replaced, metal pollution will occur.