The basic content of the hydraulic system commissioning of the hydraulic lifting platform
A, the hydraulic system before the scheduling of preparatory work
1, the hydraulic system to be debugged must be in the cycle of flushing qualified before entering the commissioning state.
2, hydraulic drive of the host equipment all installed, moving parts in good condition and checked and qualified to enter the commissioning state.
3、Control hydraulic systems (Hydraulic systems) of electrical equipment and wiring are all installed and inspected and qualified.
4、Familiar with the technical documents required for commissioning, such as hydraulic schematic diagram, piping installation diagram, system manual, system commissioning manual, etc. According to the above technical documents, inspect whether the piping connection is correct and reliable, whether the selected fluid meets the requirements of the technical documents, whether the oil level in the tank reaches the specified height, and determine the position of the hydraulic components according to the schematic diagram and the assembly diagram (position ).
5、Clear the debris around the mainframe and hydraulic equipment, the commissioning site should have the necessary obvious safety facilities and signs, and be managed by a person in charge.
6, the commissioning personnel should be clearly divided, unified command, the necessary training for the operator, equipped with a walkie-talkie, if necessary, to facilitate communication.
B, the hydraulic system scheduling steps
1、Check before commissioning
1）Check and confirm each hydraulic cylinder according to the system schematic, assembly diagram and piping diagram by which branch of the solenoid valve operation.
2）Individually commutate the solenoid valves at no load to confirm whether the electrical action is correct, flexible and in accordance with the action sequence requirements.
(3) the pump suction line, return line shut-off valve open, pump outlet relief valve and the system in the safety valve handle all loose; pressure reducing valve will be placed in the pressure position.
4）Place the flow control valve in the small opening position.
5）In accordance with the requirements of the instruction manual, fill the accumulator with nitrogen.
2、Start the hydraulic pump
1）Turn the coupling between the motor and the hydraulic pump by hand to make sure there is no interference and the rotation is flexible.
2）Turn on the motor, check whether the motor steering is consistent with the hydraulic pump steering sign, confirm and turn on the motor several times, and press the motor start button after there is no abnormality, then the hydraulic pump will start working.
After starting the hydraulic pump, adjust the system pressure to about 1.0MPa, control the solenoid valve to make the oil circulate to each branch separately, twist the exhaust valve set on the pipeline to discharge the gas in the pipeline; when the oil overflows continuously, close the exhaust valve. When the hydraulic cylinder is exhausted, you can open the exhaust valve on the side of the piston rod of the hydraulic cylinder, the solenoid valve will act, the piston rod will move and push out the air, and close the exhaust valve when it rises to the upper stop. Open the other side of the exhaust valve, so that the hydraulic cylinder down, discharge the air in the rodless cavity, repeat the above exhaust method, until the hydraulic cylinder in the air exhaust.
4、System pressure test
System pressure test mainly refers to the site pipeline, hydraulic equipment pressure test should be carried out at the manufacturer. For hydraulic piping, the pressure test pressure should be 1.5 times the working pressure. High pressure system with working pressure ≥ 21MPa, the pressure of the pressure test should be 1.25 times of the working pressure. If the system itself hydraulic pump can reach the pressure resistance value, it is not necessary to use electric test pump. The process of pressure boosting should be carried out gradually in sections, not once to reach the peak, each level of elevation, should be maintained for a few minutes, and observe whether the pipeline is normal. It is strictly forbidden to manipulate the reversing valve during the test pressure.
After the test pressure is finished, restore the system pressure to the ready commissioning state, and then adjust and set the system pressure, flow rate (unit: cubic meter per second), speed and stroke according to the commissioning manual, which can be carried out manually and then electrically, including the setting of pressure relay and stroke switch. After the manual adjustment is finished, the no-load linkage test run should be started after the machine, electric and hydraulic test run without load is completed.
6、Load test run
After the equipment starts to run, the load should be gradually increased, such as the situation is normal, before the load test run. After successful load test run, the system should be checked in time to see if it is working normally, and the pressure, noise, vibration, speed, temperature rise and liquid level should be checked comprehensively, and records should be made according to the test run requirements.