How should a hydraulic system using a Nippon Sharyo hydraulic pump be tuned?

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After the Niigata hydraulic oil pumps are used in hydraulic systems for the debugging of hydraulic equipment and after proper circulation flushing, it is necessary to carry out appropriate adjustments and tests on the hydraulic system. These adjustments ensure that the system meets all technical specifications and can function properly according to the actual production requirements, even under heavy load conditions. 3.1 Preparatory work before hydraulic system commissioning 1) The hydraulic system to be commissioned must pass cyclic flushing before it can be put into the commissioning phase. 2) Once all the hydraulically driven main equipment has been installed, and the moving parts are in good condition and have passed inspection, the system enters the debugging phase. 3) All electrical equipment and wiring for controlling the hydraulic system have been installed and passed inspection. 4) Be familiar with the technical documents required for debugging, such as hydraulic schematic diagrams, pipeline installation diagrams, system operation manuals, and system debugging instructions. Based on the above technical documents, check whether the pipeline connections are correct and secure, whether the selected oil meets the requirements specified in the technical documents, and whether the oil level in the tank is at the specified height. Determine the positions of various hydraulic components using the schematic diagrams and assembly drawings. 5) Remove debris around the host and hydraulic equipment; the testing site should be equipped with necessary and obvious safety facilities and signs, and there should be a dedicated person in charge of their maintenance. 6) The personnel involved in the commissioning should have clear roles and be under unified command; the operators should receive necessary training, and walkie-talkies should be provided where necessary to facilitate communication. 3.2 Hydraulic System Scheduling Steps 3.2.1 Checks Before Debugging 1) Check and confirm, based on the system schematic diagram, assembly diagram, and piping diagram, which solenoid valve controls each hydraulic cylinder. 2) The solenoid valves are switched under no-load conditions to verify that the electrical operation is correct and smooth, and meets the requirements regarding the sequence of operations. 3) Open the stop valves on the pump’s suction pipe and return line, and loosen all the handles of the pump outlet relief valve and the safety valves in the system ； Set the pressure relief valve to the lowest pressure position. 4) The flow control valve is placed in the small-opening position. 5) Fill the accumulator with nitrogen as required by the instruction manual. 3.2.2 Starting the hydraulic pump 1) Manually turn the coupling between the motor and the hydraulic pump to confirm there is no interference and that it rotates smoothly. 2) Turn on the motor in pulse mode to check whether its rotation direction matches the direction indicated by the hydraulic pump; once this is confirmed, turn it on in pulse mode several times more. If there are no abnormalities, press the motor start button and the hydraulic pump will begin to operate. 3.2.3 After starting the hydraulic pump through system venting, adjust the system pressure to around 1.0 MPa. Control the solenoid valves to switch directions so that the oil circulates to each branch. Turn the vent valve installed on the pipeline to discharge the gas from it ； When oil keeps overflowing, close the exhaust valve. When exhausting the hydraulic cylinder, the exhaust valve on the extension side of the piston rod can be opened; the solenoid valve activates, causing the piston rod to move and expel the air. When it reaches the top dead center, the exhaust valve closes. Open the exhaust valve on the other side to allow the hydraulic cylinder to move downward, thereby expelling the air from the rodless chamber. Repeat the aforementioned exhaust procedure until all the air in the hydraulic cylinder has been removed. 3.2.4 System pressure test: The system pressure test mainly refers to the pressure testing of pipelines and hydraulic equipment on-site; such testing should be carried out at the manufacturer’s facility. For hydraulic pipelines, the pressure for the pressure resistance test should be 1.5 times the maximum operating pressure. For high-pressure systems with a working pressure of ≥21 MPa, the pressure for the pressure resistance test should be 1.25 times the maximum working pressure. If the system’s own hydraulic pump can reach the required pressure rating, there is no need to use an electric pressure testing pump. The pressure increase should be carried out in gradual stages; it is not possible to reach the peak value all at once. For each increase in pressure level, wait for a few minutes and check whether the pipeline is functioning properly. It is strictly prohibited to operate the directional valve during pressure testing. 3.2.5 After the no-load commissioning pressure testing is completed, restore the system pressure to the state ready for commissioning. Then, in accordance with the instructions provided in the commissioning manual, adjust and set the system’s pressure, flow rate, speed, and stroke. This can be done branch by branch, starting with manual adjustments before moving on to electric ones; it also includes setting the pressure relays and limit switches. After the manual adjustments are complete, the no-load coordinated test run should be initiated only after the equipment has been tested separately under mechanical, electrical, and hydraulic conditions with no load. 3.2.6 After the load testing equipment starts operating, the load should be increased gradually; only if everything is functioning properly can a test at maximum load be conducted. After a successful test run at maximum load, it is necessary to promptly check whether the system is operating properly. A comprehensive inspection of parameters such as pressure, noise, vibration, speed, temperature rise, and liquid level should be carried out, with records being made in accordance with the requirements of the test run. 3.3 Acceptance of the hydraulic system During the testing of the hydraulic system, all design values shall be checked in accordance with the design specifications; the operating condition of the hydraulic system shall be determined based on the actual test results. The acceptance procedure is carried out by the designer, the user, the manufacturer, and the installation party.