Advanced forging technology

Author: Editor-in-Chief: Li Mingjie
Publisher:
Publish Date: 1999-12-01
Features:
Section: Hydraulic Transmission
Hydraulic transmission is a technology that uses pressurized liquid as the working medium to convert and control energy through various hydraulic components forming required control circuits. Hydraulic components can be categorized by their functions into power components (hydraulic pumps), actuating components (hydraulic cylinders), control components (hydraulic control valves), and auxiliary components (oil tanks), among others. Currently, hydraulic components in China have been series and standardized from low to high pressure. Hydraulic transmission technology is widely used in forging and pressing machinery, lifting machinery, machine tool industry, and various mechanical fields.
1. Hydraulic Transmission
1.1 Working Principle
Figure 1-1 shows a simple hydraulic system transmission diagram. The hydraulic pump 3 is driven by an electric motor to draw oil from the oil tank 1. The oil flows through the throttle valve 6 to the directional valve 7. If both sides of the solenoid directional valve are de-energized, the valve core is in the position shown in Figure 1-1a. At this time, the channels P, T, A, and B are completely closed, so the pressure oil, driven by the hydraulic pump's discharge, increases in pressure. When the oil pressure exceeds the set pressure of the relief valve 5, the pressure oil pushes the relief valve core back to the oil tank 1.
If the solenoid on the left side of the directional valve 7 is energized, the valve core is in the position shown in Figure 1-1b. At this time, the pipelines P and A are connected, and B and T are connected. The pressure oil flows through the P-A channel of the directional valve into the left chamber of the hydraulic cylinder 8, pushing the piston 9 to move the worktable to the right under the action of the pressure oil. Meanwhile, the oil in the right chamber of the hydraulic cylinder flows through the pipeline B and returns to the oil tank 1 through the B-T channel of the directional valve.
If the solenoid on the right side of the directional valve 7 is energized, the valve core is in the position shown in Figure 1-1c. At this time, the pipelines P and B are connected, and A and T are connected. Under this condition, the pressure oil can flow through the P-B channel of the directional valve into the right chamber of the hydraulic cylinder 8, pushing the worktable to move to the left. Meanwhile, the oil in the left chamber of the hydraulic cylinder flows back to the oil tank 1 through the A-T channel of the directional valve.