As for the injection volume, the large diameter barrel […]
As for the injection volume, the large diameter barrel is often too large. The recommended injection volume is 40% to 70% of the barrel capacity. The total moulding cycle of thin-walled products is greatly shortened, and it is possible to reduce the minimum injection volume to 20 barrel capacity. %~30%. The user must be very careful when moulding, because for materials, a small injection volume means that the material stays in the barrel for a longer period of time, which can result in a decrease in product performance.
Speed is one of the key factors for the success of thin-wall injection moulding. Rapid filling and high pressure can inject molten thermoplastic material into the mould cavity at high speed to prevent the gate from freezing. If a standard part is filled in two seconds, the mould thickness is reduced by 25%, and it is possible to reduce the filling time by 50%, just 1 second.
One of the advantages of thin wall injection moulding is that when the thickness is reduced, less material needs to be cooled. As the thickness is reduced, the moulding cycle can be cut in half. The proper arrangement of the melt delivery device allows the hot runners and runners to not interfere with the shortening of the moulding cycle. The use of hot runners and sprue bushings helps to minimize moulding cycles.
In addition, mould materials should also be considered. P20 steel is widely used in the moulding of traditional products, but due to the higher pressure of thin-wall injection moulding, the mould must be made very strong. H-13 and other hard steels add an extra safety factor to thin-walled moulds. However, the cost of a solid mould may be 30% to 40% higher than a standard mould. But the increased cost is usually offset by increased production performance.