The integrated actuator (pneumatically or hydraulically actuated) controls a radially positioned piston via a lever mechanism. The lever mechanism is constructed in such a way that an automatic opening of the nozzle is ensured in case of overpressure. This type is not suitable for processing foaming agent. Changing raw materials or changing colours can be done very quickly. (similar to an open nozzle)

The active operated shut off nozzle valve with piston are used with shear sensitive thermoplastics with high viscosity and high injection rates.

Advantages:

• Suitable for shear sensitive materials.
• No material leakage during dosing.
• Shorter cycle time, higher productivity.
• Process reliability and stability.
• Excellent colour change performance.

Disadvantages:

• Not suitable when processing foaming agent.

The shut off nozzles are supplied with heater band and built-in thermocouple type J.

Optional for these nozzles are filters or mixers.