Tue Mar 21 15:08:14 CST 2023
The development of the correct die-casting process, the correct and skilled operation of the die-caster and the high quality of mould maintenance are essential to improve production efficiency, ensure the quality of die-castings, reduce the scrap rate, reduce mould failures and extend mould life.
Develop the correct die casting process
The die-casting process is a reflection of the technical level of a die-casting factory, which can combine the correct production factors such as die-casting machine characteristics, mould characteristics, casting characteristics and die-casting alloy characteristics to produce die-casting products that meet customer requirements at the lowest cost. Therefore, attention must be paid to the selection and training of die-casting process engineers. The die-casting process engineer is the total technical person in charge of the die-casting production site, in addition to formulating the correct die-casting process and revising the die-casting process in time according to the changes in production elements, he is also responsible for the training and improvement of mould installation and adjustment workers, die-casting operators and mould maintenance workers.
(1) Determine the most reasonable production rate and specify the cycle time for each die casting cycle. Too low productivity is certainly not conducive to improving economic efficiency, too high productivity is often at the expense of mould life and castings qualified rate as the price, calculate the total account fine account economic benefits may be worse.
(2) determine the correct die-casting parameters. In the premise of ensuring that the castings meet customer quality standards, should make the lowest die casting speed, die casting pressure, alloy temperature. This will help to reduce the machine and mould load, reduce failure and improve life. According to the die casting machine characteristics, mould characteristics, casting characteristics, die casting aluminium alloy characteristics isosceles triangle, determine the fast press injection speed, press injection pressure, boost pressure, slow press injection stroke, fast press injection stroke, punch follow out distance, push out stroke, holding time, push out reset time, alloy temperature, mould temperature, etc.
(3) When using water-based coatings, a strict and detailed spraying process must be developed. Paint brands, the ratio of paint to water, the amount of spraying (or spraying time) and spraying sequence for each part of the mould, compressed air pressure, the distance between the spray gun and the moulding surface, the spraying direction and the angle of the moulding surface, etc.
(4) According to the actual die-casting mould to determine the correct mould cooling scheme. The correct mould cooling scheme has a great impact on production efficiency, casting quality and mould life. Program should specify the cooling water account method, die-casting several die times to start cooling, a few die times apart in several times to the cooling water valve open to the prescribed opening degree. Point cooling system cooling intensity should be die-casting process engineer on-site adjustment, with spraying to achieve mold thermal balance.
(5) Specify different lubrication frequencies for different sliding parts, such as punches, guide pillars, guide bushings, core extraction mechanisms, push rods, reset rods, etc.
(6) Develop a die casting operation procedure for each die casting and train and supervise die casters to operate according to the procedure.
(7) Determine the appropriate preventive maintenance intervals for the moulds according to their complexity and newness. The appropriate preventive maintenance cycle should be the number of die-casting moulds that will fail in use and have not yet failed. A mould that has already failed in use, cannot continue production and is forced to be repaired is not the method being advocated.
(8) Depending on the complexity of the mould, the degree of newness and the risk of sticking, the module stress relief cycle is determined (usually carried out once every 5,000 to 15,000 moulds) and whether surface treatment is required.