Summary of experience in commissioning and acceptance of hydraulic system

After the hydraulic equipment installation and circulation flushing are qualified, it is necessary to adjust the hydraulic system for test run, so that it can make necessary adjustments according to the actual production process requirements under the premise of meeting the technical parameters, so as to achieve normal operation under heavy load.

1.1　Preparatory work before commissioning of hydraulic system

①The hydraulic system to be debugged must be in the circulating rinse qualified before it can enter the debugging state.

②All the hydraulic drive host equipment is installed, and the moving parts are in good condition and qualified after inspection, entering the debugging state.

③All the electrical equipment and lines of the control hydraulic system have been installed and checked.

④Familiar with the technical documents required for debugging, such as hydraulic schematic diagram, pipeline installation diagram, system operation manual, system debugging manual, etc. According to the above technical documents, check whether the pipeline connection is correct and reliable, whether the selected oil meets the requirements of the technical documents, whether the oil level in the tank reaches the specified height, and determine the position of each hydraulic component according to the schematic diagram and assembly drawing.

⑤Remove the debris around the main engine and hydraulic equipment, and the commissioning site should have the necessary obvious safety facilities and signs, and be managed by a special person.

⑥The personnel participating in the debugging should have a clear division of labor, unified command, necessary training for the operator, and be equipped with walkie-talkies if necessary to facilitate contact.

1.2　Hydraulic system commissioning steps

1.2.1　Check before commissioning

①Check whether the connection is correct according to the system schematic, assembly drawing and piping drawing, and confirm which branch electromagnetic directional valve operates each hydraulic cylinder.

②The electromagnetic directional valve is carried out no-load directional change respectively to confirm whether   the electrical action is correct,   flexible   and   in line with the action sequence requirements.

③Open the stop valve on the pump suction pipe and return pipe, loosen the relief valve at the pump outlet and the pressure regulating handwheel of the safety valve in the system; Set the reducing valve in the lowest pressure position.

④The flow control valve is placed in a small opening position.

⑤Fill the accumulator with nitrogen according to the instructions.

1.2.2　Start the hydraulic pump

①Rotate the coupling between the motor and the hydraulic pump by hand to ensure that there is no interference and rotation is flexible.

②Point the motor, determine whether the motor steering is consistent with the steering sign of the hydraulic pump, after confirming the continuous point several times, press the motor start button after no abnormal conditions, and the hydraulic pump starts to work.

1.2.3　System exhaust

After starting the hydraulic pump, adjust the system pressure to about 1.0MPa, control the reversing of the solenoid valve respectively, so that the oil is circulated to each branch, and twist the exhaust valve set on the pipeline to discharge the gas in the pipeline; When the oil continues to overflow, close the exhaust valve. When the hydraulic cylinder is venting, the exhaust valve of the piston rod extending out of the hydraulic cylinder can be opened, the solenoid valve acts, the piston rod moves, the air is squeezed out, and the exhaust valve is closed when it rises to the top dead center. Open the exhaust valve on the other side, let the hydraulic cylinder down, discharge the air in the rodless chamber, repeat the above exhaust method until the air in the hydraulic cylinder is drained.

1.2.4　System withstand voltage test

The pressure test of the system mainly refers to the pressure test of the field pipeline, and the pressure test of the hydraulic equipment should be carried out in the manufacturer. For hydraulic pipelines, the pressure of the pressure test should be 1.5 times the maximum working pressure. For high pressure systems with working pressure ≥21MPa, the pressure of the pressure test should be 1.25 times the maximum working pressure. If the system's own hydraulic pump can reach the pressure value, it is not necessary to use an electric pressure test pump. During the pressure increase process, it should be gradually segmented, and it cannot reach the peak value at one time. When each level is increased, it should be kept for a few minutes, and observe whether the pipeline is normal. Do not operate the reversing valve during the pressure test.

1.2.5　No-load commissioning

After the pressure test, the system pressure is restored to the ready debugging state, and then the system pressure, flow, speed and stroke are adjusted and set according to the content specified in the debugging instructions, which can be carried out one by one in the order of manual and electric first, including the setting of pressure relay and stroke switch. After the manual adjustment is completed, the no-load linkage test should be started after the equipment, electricity and liquid   are tested separately   without   load.

1.2.6　Load test

After the equipment starts to run, the load should be gradually increased, if the situation is normal, the maximum load test can be carried out. After the maximum load test is successful, the system should be checked in time to check whether the working condition is normal, and the pressure, noise, vibration, speed, temperature rise, liquid level, etc. should be comprehensively checked, and records should be made according to the test requirements.

1.3　Acceptance of hydraulic system

During the test of the hydraulic system, all the design values should be tested according to the design content, and the operating status of the hydraulic system should be determined according to the actual recorded results. The design, user, manufacturer and installation unit should hand in the acceptance and sign the relevant documents.