Clamping force is put on a mold to keep the mold closed against the pressure of the injected molten plastics.
Clamping begins with confirming clamp up of the mold after the mold closing process finishes and continues until clamping force reaches the official capacity.
The maximum force to clamp a mold is used to specify a molding machine, and represents the size of a molding machine.
Closing force is exerted from full mold opening to clamp up of the movable side of the mold to the fixed side.
A mold is kept closed under low pressure until the completion to avoid damage to the mold.
Closing force is usually divided into two steps: it uses low pressure in the early phase of closing and becomes higher immediately before the completion.
The closing speed is divided into two levels, also, to avoid damaging a mold if the mold is closed rapidly.
Also, if foreign matter is left inside the mold, clamping force can avoid damage to the mold.
The process of closing and clamping is as follows:
High speed closing → Slow closing (Mold protection circuit starts) → Clamping (pressure rising)
