1. When the head pressure exceeds the set alarm value, the material pressure alarm light will be on and the machine will stop automatically.

2. The main motor and the oil pump motor have electrical interlock, that is, if the oil pump motor does not start, the main motor cannot start; if the main motor does not stop, the oil pump motor cannot stop.

3. The main motor and feeding motor have electrical chain, that is, if the main motor does not start, the feeding motor cannot start; if the feeding motor does not stop, the main motor cannot stop. The main motor control cabinet has over-current protection, which has been set before leaving the factory. In addition, it also has mechanical protection device, generally nylon shear pin type safety coupling. When the design torque is exceeded, the shear pin is cut off and the transmission box stops working.

The twin-screws are frequency-controlled, AC motor driven or DC speed-controlled, DC motor driven. The speed reduction and twin-screw drive are within the same box, with compact dimensions. A safety coupling with a shear pin is used to protect the screw and the transmission box from damage due to overload.