Platens/Clamping System/Tie Bars

The fixed or stationary platen never moves, and the stationary side of the mould or “A” side is mounted here.

The movable platen moves left to right. This platen supplies the necessary force required to hold the clamp closed during injection and packing. Most of the required tonnage is used during the packing phase.


Different types of clamping systems exist such as the toggle clamp system, which works on the leverage principle. On a toggle type clamp, a small hydraulic cylinder moves the toggle.

The four tie bars keep the clamp unit together. However, smaller machines may only have two tie bars.