What is the use of “pumps” in the extruder hydraulic system?

Extruders have a lot of knowledge to learn. Only when they are familiar with and understand enough can they avoid some unnecessary troubles. Correct use and understanding can effectively improve work efficiency. Therefore, let’s learn some knowledge about the three extruders.
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1. Why is there a pilot pump and two main pumps in the hydraulic system of the extruder?
The reason why there is a pilot pump and two main pumps on the hydraulic system is that the pilot pump supplies oil to the main pump, thus improving the sensitivity of the variable pump. That’s why it was set up like this.

2. Why is the parallel pump disconnected?
The extruder has the function of combining the oil cylinder and the pump, that is, the oil of the vane pump is also supplied to the main cylinder for fast forwarding and working, so that the speed of the main cylinder can be reached, and the pressure time after working is shortened, because both the vane pump and the plunger pump are driven by the same motor. If the pressure of the plunger pump reaches 150MPA and the pressure of the plunger pump is 210MPA higher, the vane pump will also start pressing at the same time, which will drag the motor to death, and the motor will not be able to load and burn off. Therefore, when the pressure of the plunger pump reaches the set pressure, the vane pump will be powered off to return oil and cannot start

3. What is the function of the pressure pump?
Pressure guiding is often referred to as control oil, which is used to control the regulating valve core of plunger pump and the valve core of reversing valve. Pressure guiding oil is controlled by electromagnetic valve.
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