The use of plastic moulds in the field of passenger car […]
The use of plastic moulds in the field of passenger cars is inseparable from the development of the car profession. In recent years, the demand for car professions has been steadily progressing, so it has also promoted the rapid development of injection moulding plants. In recent years, with the widespread use of cars in family life, the production speed and quality of traditional car plastic casings are no longer satisfactory. Now the car profession requires plastic moulds.
Plastic moulds are classified as consumables, and the general dosage is increased, which is more obvious in the parts often used in cars. More than 90% of the auto parts are injection-moulded with plastic moulds. At the same time, cold and hot work and plastic shell moulds are used. In general, every 10,000 cars produced by an injection moulding plant requires 0.12 tons of moulds. Generally, no less than 1500 moulds are needed to make a car, including nearly 1,000 stamping moulds and nearly 500 interior moulds.
Measures to prevent damage during plastic mould processing:
1. Outstanding casting structure design
The wall thickness of the casting should be as uniform as possible to prevent the occurrence of thermal knots in order to reduce the thermal fatigue caused by the heat gathering in the mould part. There should be proper casting fillets at the corners of the casting to prevent sharp corners on the mould from causing stress.
2. Reasonable plastic mould structure design
(1) Each component in the mould should have sufficient stiffness and strength to withstand pressure without deformation. The mould wall thickness must be satisfied to reduce deformation.
(2) The design of the pouring system minimizes the impact and erosion on the core.
(3) Correctly select the official cooperation and appearance roughness of each component.
(4) Adhere to mould thermal balance.
3. Standard heat treatment process
The metallographic arrangement of the material can be changed through heat treatment, insisting on the necessary strength, hardness, dimensional stability at high temperature, thermal fatigue resistance and material cutting performance. The correct heat treatment process will get a very good effect, and the performance of the steel is controlled by the quenching temperature and time, cooling rate and tempering temperature.
4. Manipulation of Die Casting Production Process
(1) Temperature control: the preheating temperature and working temperature of the mould; the casting temperature of the alloy, under the premise of insisting on moulding, use a lower casting temperature.
(2) Reasonable die casting process: specific pressure and filling speed.
(3) Adjust the clamping force of the machine to make the mould load uniform. Pay attention to the scraps on the surface of the mould, so as not to cause the mould surface to be unevenly deformed due to these residues during mould clamping.
(4) Strict control of alloy melting to reduce gas in metal liquid.