To determine whether the hydraulic valve meets the usage conditions, it can be systematically judged from four dimensions: matching of operating parameters, compliance of structure and installation, compliance with performance testing standards, and environmental and long-term reliability. The specific methods are as follows:
Matching and verification of working condition parameters
Pressure adaptation: The nominal pressure of the hydraulic valve should be ≥ 1.5 times the maximum working pressure of the system. In the closed state, it can withstand 1.1 times the rated working pressure without leakage. When opened, the valve body can withstand 2 times the working pressure without deformation.
Flow adaptation: The valve diameter and rated flow should match the actual flow rate of the system to avoid excessive pressure drop caused by excessive flow or delayed action caused by insufficient flow.
Media compatibility: The sealing material should be compatible with the type of hydraulic oil in the system, and special media (such as emulsions and synthetic oils) should use valve components made of corresponding corrosion-resistant materials.
Compliance inspection of structure and installation
Appearance and cleanliness: The valve body should be free of deformation and rust, and the internal particle contamination should meet the limits of 18/15/12 in ISO 4406:2023, with no residual debris or oil stains.
Sealing and connection: The sealing components are intact without deformation, the valve body and pipeline interface are aligned without deviation, the bolt tightening torque meets the design standards, and the anti loosening spring washers are complete and effective.
Interface matching: The connection thread (BSPP/NPT) and installation surface size must comply with national standards such as GB/T 2514, and be fully compatible with the system pipeline.
Core performance testing and verification
Pressure characteristic test: The pressure adjustment deviation of pressure control valves such as overflow valves should be ≤ ± 3% of the set value (under working conditions below 10MPa), the system pressure fluctuation should not exceed ± 15%, and there should be no pressure establishment or sudden rise and fall problems.
Action response test: Directional control valves such as directional valves are sensitive and free of jamming. The response delay from operating instructions to executing component actions is ≤ 0.5 seconds, and there is no switching delay or shaking phenomenon.
Sealing leakage test: The valve component is maintained at rated pressure for 10 minutes, and the internal leakage meets the limit value of JB/T 7039 standard, with no external oil leakage problem.
Electromagnetic performance test: The current value of the solenoid valve coil is within the rated range, and it has passed the ± 2kV fast transient pulse group immunity test without any misoperation caused by electromagnetic interference.
Confirmation of Environment and Long term Reliability
Environmental tolerance: The working temperature range of the valve covers the actual working conditions of the system, and the valve body material has passed the -20 ℃ Charpy impact test, which can adapt to high and low temperature, vibration and impact environments on site.
Compliance certification: The product complies with current national standards such as GB/T 17490, and requires corresponding international certifications such as CE and ISO for export scenarios. Special industries (such as ships) require certification from CCS classification society.
Operation and maintenance adaptation: The structure is easy to disassemble and maintain, with strong universality of accessories, meeting the long-term maintenance and replacement needs of the system.