In low-pressure casting, the mold is placed in a closed holding furnace, and the cavity is connected to the metal in the furnace through a riser. When working, compressed air is added to the furnace, and the molten metal will flow from the riser into the cavity. After the molten metal solidifies, the compressed air in the furnace is released, and the unsolidified metal flows back into the furnace from the riser.

Aluminum hub and blade in torque converter coreAdoptLow pressure casting has four advantages: low pressure castingofDense casting structure, good mechanical properties; high process yieldAccording to statistics,The pass rate of the die casting process of low pressure casting is in.More than 93%, the gravity casting productivity of the same product is between 70% and 80%; the production efficiency is high, the production efficiency of the same product die-casting process is three times that of gravity casting; the surface is smooth, which will reduce the machining allowance.

Low pressure casting production processProcess

1,Mold inspection. The paint should be cleaned before using the mold. After the production cycle,IfPaint failure or uneven surface,Need to be polished with a grinding wheel,Then clean the aluminum shavings of the eject lever and clean the exhaust plug.

2、The working temperature of the baking mold is (360±10)℃, so the mold should be baked to working temperature before low pressure casting.

3,Coating: When the mold is heatedSpray the coating at 300 ℃. The coating must be uniform and not sag. The coating mainly plays the following roles: to prevent corrosion of aluminum alloy cavity, to extendused to carry outLow pressure casting mold life. Secondly, the aluminum alloy is prevented from adhering to the cavity or the parting surface, so that the production can be carried out continuously and rapidly. The coating makes the cavity have a layer of heat insulation protection structure, so that the molten metal flows into the cavity easily and smoothly, reduces the flow resistance of molten aluminum, and improves the filling performance of molten metal.

4,Setting of process parameters.The process parameters of low pressure casting are mainly the temperature of aluminum water, the pressurization speed and pressure setting of the equipment. These three factors willDirectAffect the quality of low pressure casting castings,If the process parameters are not set, it willLead to defects such as sticky sand and insufficient pouring. Therefore, parameter setting is very important for low pressure casting.

5,Low pressure casting pouring.