Operation and precautions for pouring large steel castings
The pouring process is a relatively important processing process in large steel castings. If this link is not handled properly, it will be very difficult to produce more qualified steel castings. Therefore, in the production of steel castings, it is necessary to carry out pouring according to the requirements. various operations.
Manufacturers must carry out preparatory work before pouring to ensure that subsequent pouring operations can proceed smoothly. Preparatory work prior to pouring includes:
1. Organize the pouring place to ensure the safety of the process can be carried out smoothly;
2. Check the repair quality of the slag tank, drying and preheating conditions, transportation and the cold activity and reliability of the tilting organization;
3. To understand the variety of cast alloys, estimate the required quantity of poured castings and the weight of molten metal, and strictly control the temperature and speed of pouring to prevent insufficient molten metal and insufficient number of castings;
In order to obtain qualified steel castings, it is necessary to control the temperature and pouring speed, and follow the pouring operating procedures:
1. The pouring temperature has a relatively large impact on the quality of the casting, and it is necessary to determine a reasonable pouring temperature range according to the type of material, the structure of the product, and the particularity. In order to obtain qualified steel castings, the pouring temperature, pouring speed, and pouring operating procedures are strictly controlled.
2. Pouring speed. Under the condition that the gas in the cavity has been discharged, a better pouring speed can be selected for the condensed casting, and a lower pouring speed can be selected for the casting that requires the completion of sequential solidification.
3. When pouring large or medium-sized pieces, the molten steel should be placed in the ladle before pouring. After pouring, wait for the condensation to end, and remove the pressure iron and box clips in time to eliminate the short-term resistance of the casting and prevent the casting from forming. Crack defect.