Graphite crucible 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 to rapid temperature rise and rapid temperature drop. It has strong corrosion resistance and excellent chemical stability to acid and alkali solutions. In metallurgy, casting, machinery, chemical industry and other industrial sectors, it is widely used for smelting alloy tool steel, nonferrous metals and their alloys. It has good technical and economic effects. Matters needing attention in using graphite crucible: 1. Handle with care, don't damage the surface coating, and don't roll. 2. Store in a dry environment, and don't get wet. 3. When used in a coke oven, the crucible base should be used at the bottom, and the diameter of the base should be slightly larger than that of the crucible base, so that the bottom can be fully supported. 4. Don't tilt when loading the furnace, and the top opening should not be higher than the outlet. The crucible brick should be higher than the crucible mouth. The furnace cover should bear the load on the furnace wall. 5. The diameter of the coke block used should be less than the distance between the furnace wall and the crucible, and it should fall from 5℃ when it is added, and it should not be mashed. 6. Before use, the crucible should be heated from the air temperature to 200℃ within 1- 1.5 hours (especially during the initial baking, the crucible must be continuously rotated to make the temperature inside and outside the crucible rise slowly, not exceeding 65438+). After the water vapor is exhausted, continue to heat up). Then 1 hour is heated to about 800℃, and the baking time should not be too long. (Improper preheating will cause peeling and cracking, which is not a quality problem. I'm sorry, the company is not responsible for returning goods. 7. The inner wall of the furnace must be kept intact to avoid flame deviation. 8. Heat with a burner, and don't spray the flame directly on the crucible. Should be sprayed on the crucible base. 9. It is proposed to use corresponding crucible tongs for loading. 10. Load the metal, break the bottom first and then insert the metal ingot, but don't put it too close, and put it horizontally to avoid the crucible from cracking due to metal expansion. 1 1. Once the crucible is used, it is best to melt continuously to reduce the intermittent time. If you stop halfway, it should be left. So as to avoid rupture during continuous use. 13. The dosage of refining agent must be strictly controlled in the smelting process. Excessive addition will shorten the service life of crucible, and slag should be cleaned frequently to avoid affecting the appearance and capacity of crucible guide. Excessive slagging can also lead to cracking of the upper part.