Low pressure casting is to put the mold in a closed holding furnace, and the cavity is connected with the metal liquid in the furnace through the riser. During operation, pressurized air is added to the furnace and 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.

Many parts are manufactured using low-pressure casting technology, such as aluminum wheels and blades in the torque converter core. The resulting castings have a dense structure and good mechanical properties; the yield of the process is high, and the same product as gravity casting,The yield of the process is70% to 80%. The production efficiency is high, and the production efficiency of the die-casting process of the same product is three times that of gravity casting.andThe surface is smooth and clean, which can reduce the machining allowance.

InStartWhen low pressure casting, please check the mold first. Paint failure or uneven surface at the end of the production cyclewhen,It needs to be polished with a grinding wheel. Then clean the aluminum shavings of the eject lever and clean the exhaust plug,Then bake the mold, the working temperature is (360±10)℃, so the mold should be baked to the working temperature before working.

When the low pressure casting mold is heatedSpray paint at 300°C, and the paint must be uniform and free from sagging. This can prevent aluminum alloy corrosion cavity, extend the life of the mold; can alsoPrevent aluminum alloy from adhering to the cavity or parting surface, so that production can be carried out continuously and rapidly; it can also make the cavity have a layer of heat insulation layer, protect the organization, make the molten metal flow into the cavity easily and smoothly, reduce the flow resistance of molten aluminum, and improve the filling performance of molten metal.

Then set the core and set the low pressure casting process parameters. The process parameters of low pressure casting are mainly the temperature of aluminum water, the pressure speed and pressure setting of the equipment. These three factors will affect the quality of castings,If the setting is not goodLead to defects such as sticking sand, insufficient pouring and blockage.Therefore, parameter setting is very important for casting.

Compared with traditional gravity casting, low-pressure casting can greatly increase the output of castings and have high working efficiency. Due to the crystallization under pressure, the structure of the casting is dense and the tensile strength can reachMore than 200MPa. However, low-pressure casting has higher requirements for equipment, molds and processesYou need to be more careful when casting..