Clamping Force Calculator

Injection molding machines are primarily characterized by the tonnage of the clamping force that they provide. The clamping force, measured in tons, indicates the amount of force that the clamping unit can apply to the mold to keep it securely closed during the injection of the molten plastic. A sufficient clamping force is required to oppose the separating force that is pushing the mold open. The separating force is a result of the cavity pressure inside the mold (caused by the injection pressure of the material) and the shot projected area, on which this pressure is acting. Therefore, a larger part, more mold cavities, and certain materials will require a larger clamping force. An insufficient clamping force will result in excessive flash or other part defects.