Four Methods For No-load Debugging Of Hydraulic Systems in Hydraulic Presses

No-load debugging refers to checking the working condition of the hydraulic device under no-load operating conditions of the system. The debugging method is as follows:
(1) Starting the hydraulic pump motor from intermittent to continuous, if there are more than two hydraulic pump motors in the system
Large electric motors should be started in sequence to avoid circuit overload and tripping; If the control oil route in the system controls the hydraulic pump to supply oil separately,
You should start the control hydraulic pump first. After starting the hydraulic pump, observe the working condition of the pump. If the oil discharge and operation are normal, debugging can be carried out.
(2) The adjustment of hydraulic pressure valves and pressure relays should be based on their positions on the hydraulic system schematic diagram
The pressure valves near the source should be adjusted in sequence, and the adjustment should be made when the moving parts are in the "stop" position or in a low-speed motion state,
Observe the working condition of the pressure gauge and oil circuit while adjusting the pressure from low to high, and pay attention to checking the connections of various pipelines and hydraulic components in the hydraulic press system
Check for oil leakage at the joint surface until it reaches its specified value. Tighten the locking nut of the pressure valve and tighten the corresponding pressure gauge oil circuit
Close to prevent damage to the pressure gauge due to changes in pressure values. When adjusting the pressure relay, first adjust the return interval, then adjust the
Complete the main spring. For pressure relays that signal a loss of pressure, the adjustment pressure should be lower than the adjustment pressure of the back pressure valve in the return oil circuit.
The adjustment pressure of the safety valve at the outlet of the hydraulic pump in the main oil circuit is generally greater than 10% of the working pressure required to push the actuator-
25%; The pressure valve of the fast moving hydraulic pump is generally adjusted to a pressure greater than 10L70~200-/0 of the required pressure. Unloading pressure one
Generally, it should be less than 0.1-0.2MPa. If unloading Yanli oil is used to supply oil to the control oil circuit and lubrication oil circuit, its unloading pressure should be maintained
0.3-0.6MPa. The adjustment pressure of the pressure relay is generally 0.3-0-5MPa lower than the oil supply pressure.
(3) Press the corresponding button to exhaust the hydraulic cylinder of the hydraulic press, causing the speed of the moving parts to run from low to high and the stroke to run from small to large,
Until the full stroke rapidly reciprocates, open the exhaust valve or plug, and after multiple reciprocating movements of the cylinder, the air in the cylinder can be compressed
Out. For hydraulic systems with high pressure, the pressure should be appropriately reduced, usually to 0 About 5- lMPa, to enable the hydraulic cylinder to fully
It is advisable to move the stroke back and forth. When the exhaust plug discharges air, you can hear the sound of hissing or spurting white foam like oil and air
The oil sprayed at all times is transparent and free of bubbles. After the air in the cylinder is exhausted, the exhaust plug or valve should be closed. For precision equipment
The spare hydraulic cylinder should pay attention to the exhaust operation.
(4) Adjustment of the flow valve The flow valve has gradually opened from small to maximum during the exhaust of the hydraulic cylinder, adjusting the speed of the moving components
At this time, the speed of the hydraulic cylinder should be maximized first, then gradually turn down the flow valve and observe whether the system can reach the minimum stable speed