Technical Article

Installation and adjustment of the "five in one" hydraulic system for forging press machin

As the power, control, and output components of forging hydraulic presses, the hydraulic system consists of hydraulic oil, hydraulic pumps, hydraulic control valves, high and low pressure oil pipelines, and hydraulic cylinders. During the installation and debugging stage before using the forging hydraulic press, it is necessary to strictly control all relevant links and actively detect and avoid various potential hazards.

1. Hydraulic oil

(1) When refueling, it must pass through a filter.

(2) According to the requirements of the hydraulic system, select the appropriate grade and viscosity of hydraulic oil to ensure compatibility between hydraulic oil and hydraulic components.

(3) The filtration accuracy of the oil filter should be consistent with the system requirements; The inlet and outlet directions of the oil filter are correct.

(4) After refueling, the foam can completely disappear only after it is still for one hour.

(5) First check if the liquid level reaches the upper limit of the oil gauge, and promptly clean and replace the oil filter element to prevent blockage.

(6) The fuel tank capacity is usually taken as 8-12 times the total flow rate of the pump.

(7) There should be a certain amount of space inside the fuel tank to accommodate the thermal expansion of hydraulic oil and the excess backflow of hydraulic oil from the system during shutdown.

(8) Adequate heat dissipation space must be ensured around the fuel tank; Heating and insulation design should be attached in high-altitude areas.

2. Hydraulic pump

(1) The installation of the drive motor and hydraulic pump must be aligned correctly. The pump assembly consists of a coupling with a clearance of 2mm~4mm between the two shaft ends, and is calibrated to rotate flexibly in coaxial alignment.

(2) The electrical wiring of the hydraulic pump drive motor should ensure that its rotation direction is consistent with the marked rotation direction of the hydraulic pump, and the maximum allowable speed should not exceed the specified limit of the hydraulic pump.

(3) After starting the motor hydraulic pump assembly without error, check that the noise is within the normal range under no-load conditions.

(4) Before operating the hydraulic pump under load, remove any residual gas from the pump and inject oil into the pump body if necessary.

(5) The oil suction and return pipes of the hydraulic pump must extend to a sufficient depth below the liquid level.

(6) The suction negative pressure at the inlet of the oil pipe shall not exceed the specified pressure, and all pipelines of the pump unit must be well sealed to prevent air leakage.

(7) The bearing temperature rise of the hydraulic pump should not exceed the specified speed and working pressure.

(8) Hydraulic pump speed that is too fast or too slow can cause cavitation.

3. Hydraulic control valve

The pressure control valve can check the working status of the relief valve by loading or braking. It should be confirmed that all valves in the system are in a normal and unobstructed state, gradually increasing from low to high.

4. Hydraulic pipeline

(1) Before installing and using hydraulic pipeline connections, they must be pickled, passivated, and cleaned thoroughly.

(2) Hard pipes need to consider linear expansion and contraction caused by high and low pressure, as well as heat and cold. For longer pipelines, bent pipes or flexible hoses should be appropriately installed.

(3) The hard pipe must maintain anti vibration rigid support and fixed clamping.

(4) The bending radius of a hard pipe bend must be greater than three times its outer diameter, and the bending angle is generally not greater than a 90 ° right angle.

(5) The parallel spacing between parallel pipelines should take into account the disassembly and maintenance space of pipeline connection flanges and pipe joints.

(6) The horizontal height of the return oil pipeline connecting the fuel tank should be as low as possible below the oil discharge pipe to maintain unobstructed return oil.

5. Hydraulic cylinder

(1) Before installing the connecting pipeline of the hydraulic cylinder, it must be thoroughly cleaned.

(2) After the hydraulic cylinder starts moving and crawls, the air inside the hydraulic cylinder should be eliminated or lubrication should be applied to the sliding surface.

(3) Insufficient hydraulic cylinder pressure or unstable reciprocating motion may be caused by incorrect or ineffective installation of relevant sealing rings inside the cylinder.