The Post Machining Treatments And Working Temperature Of The Precision Casting
The basic process of precision casting in the production process is the wax injection - wax injection machine, water chiller, air conditioning, immersing sizing - pulp barrels, floating sand machine, air conditioning, dewaxing furnace, dehumidifier, dehydration bucket, stand barrel, sintering furnace, high frequency melting furnace, shock shell machine. The immersing sizing can also choose mechanical arm and automatic centralized wax system.
The working temperature of the precision casting
The casting temperature of precision casting in the production process needs to ensure that the melt has good fluidity during the injection process. The selection of temperature should be determined according to the additional injection distance and the cooling conditions, specifications, flow and alloy and so on of the injection process. The casting temperature of the product will be 50 to 110 ℃ higher than the liquidus temperature of the alloy.
The crack tendency of the precision casting round ingot is low, so that the alloy has good exhaust complement ability. The casting temperature of the ingot with diameter more than 350 mm is generally 730 ~ 750 ℃. For small diameter ingot, because of the small size of transition zone and good mechanical properties, generally according to meeting the liquidity and not forming bright crystal, the general temperature is 715 ~ 740 ℃.
The reasons for cold shut of precision casting
The problems that need to pay attention to in the process of precision casting are various, mainly because of the poor flow performance of the molten steel. In the process, in order to prevent the short run or cold shut of the cast steel, the wall thickness of steel castings can not be less than 8mm. The structural force of the gating system of the precision casting is very simple. In the using process, the section size of the equipment is larger than the cast iron, which can use hot mould or dry mold.
The post machining treatments of the precision casting
The post machining treatments of the precision casting—— cutting off machine，grinding machine, sand blaster, sand cleaning machine, furnace for heat treatment, puncher. Examine and repair——air sander, argon welding machine, grinding machine. Quality Assurance——spectrograph，three dimensional and so on. These are all common, and there are more advanced, such as vacuum casting furnace or vacuum heat treatment furnace or X-ray.