Before the multi-purpose furnace is used, the die-casting crucible must be cleaned to remove surface oil, rust, slag and oxides. In order to prevent the iron element in the cast iron crucible of the pit furnace from dissolving in the alloy, the crucible should be preheated to 150-200 ° C, spray a layer of coating on the working surface, and then heat it to 2000-300 ° C to completely remove water from the coating.
Pit furnace melting tools should be cleaned of surface dirt before use. The parts in contact with metal must be preheated and painted. The tool must not be moistened with water, otherwise it will cause the melt to splash and explode.
Before melting the alloy, it should be cleaned and preheated to remove the moisture absorbed on the surface. In order to control the alloy composition, it is recommended to use 23 new materials with 13 reflow materials.
The melting temperature must not exceed 450 ° C.
Clean up the dross on the liquid surface in the zinc pot, replenish the zinc material in time, and maintain the normal height of the molten surface, because too much scum and too low liquid level will easily cause the slag to enter the gooseneck barrel and strain the steel. The base, hammerhead, and tube itself caused stuck hammerheads, goosenecks, and hammerheads to be scrapped.
The dross on the melt is agitated calmly with a slag rake to gather them for removal.
Charge into the furnace and power transmission:
First, the charging of the furnace: Before the charging of the furnace, the electric furnace steelmaker should review the weight and alloy elements and components in the furnace according to the operation plan and the batching list, and place 1 to 2% of lime in the bottom of the furnace. After the charge is put into the furnace, the excessively high charge should be flattened or lifted out, so as not to affect the fastening of the furnace cover, while preventing the furnace cover from being arced and leaking water.
The charging of the top of the basket should be directed by a special person. After the furnace lid is opened, the basket should be hoisted into the center of the furnace quickly. It must not be too high, too low or too low. Keep the chain plate of the basket as low as possible without sticking. For the secondary feeding, do not wait for the primary feeding to completely clear before feeding, so as to avoid the spraying and splashing of the molten steel, and at the same time prevent the explosion.
2. Power transmission: After the pit furnace charge is put into the furnace, the furnace cover, electrodes, mechanical transmission system, water cooling system, electrical equipment, etc. should be inspected before power transmission. If any fault is found, it should be handled in time to avoid shutdown during the smelting process. It should be checked whether the charge is in contact with the pit furnace door or the water cooling system. If there is contact, it should be immediately eliminated to avoid being punctured after power transmission. When the electrode is not long enough, it is better to replace it before power transmission. If the position of the joint is loose to facilitate the successful completion of a well, it should be tightened first to reduce the shutdown during smelting.