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Source：中国塑料机械网

As the demand for plastic products is rapidly growing, the pace of update and replacement for injection molding machines is becoming faster as well. The injection molding machines of the early stage are all hydraulic. Recently, due to the concerns of environmental protection and energy savings, the mature development and price reduction of servomotors is driving the growth of all-electric injection molding machines. Only by comparing the two energy sources of injection molding machines can one set a clear direction for the technology development.

Fully hydraulic injection molding machine has many unique advantages in precision injection molding and for complex shape of the products. There was great development from traditional single- and multi-cylinder liquid-filled way to two-platen direct compression way. While the two-platen direct compression way is more recognized, it is also harder to control and requires high precision machining. Furthermore, the hydraulic pressure technology is harder to master.
Fully electric injection molding machines have a series of advantages, especially in protecting environment and saving energy. There is a higher accuracy of controlling the servomotor, speed is relatively more stable and it is capable of encompassing a multi-level regulation. However, these machines may have shorter service lives. In order to ensure the accuracy of the fully hydraulic injection molding machine, servo valves are used in a closed-loop control system. But, the costs of such are expensive.

Electric-hydraulic injection molding machines are hybrid hydraulic and electric driven injection molding machines. They combine the high-performance of fully hydraulic machines and the energy savings of the fully electric machines. This pairing has become the clear preference in direction with many opportunities. Regarding the cost breakdown of plastic production, though, electricity accounts for a substantial proportion. The oil pump motor particularly could consume up to 50-65% of the total power consumption. Resolving the issue of energy consumption will remain a key opportunity for the next generation molding machine design.