How to evaluate the performance of a swing check valve

‌1. Sealing performance test‌
‌Sealing surface inspection‌: Observe the flatness, smoothness and scratches or pits of the contact surface between the valve disc and the valve seat. Severely worn sealing surfaces will increase the risk of leakage‌.
‌Pressure test‌: After closing the valve, apply pressure upstream to monitor the downstream leakage. If the leakage exceeds the standard value (such as the allowable leakage rate specified by the industry), the sealing performance is judged to be unqualified‌.
‌Sealing material verification‌: Check the material of the sealing ring (such as copper alloy, rubber or polytetrafluoroethylene) to ensure that its corrosion resistance and high temperature resistance meet the working conditions.
‌2. Fluid resistance and flow characteristics evaluation‌
‌Streamlined design verification‌: The flow channel inside the valve body should be streamlined to reduce the flow resistance of the medium, which is suitable for large-caliber and low-flow rate scenarios‌.
‌Flow coefficient test‌: Through the actual working condition flow simulation, measure the pressure drop of the valve at different flow rates to ensure that its flow characteristics match the system.
‌3. Structural reliability and weather resistance analysis‌
‌Material testing‌: The valve body, valve disc and rocker are usually cast in cast iron or stainless steel. It is necessary to check whether the castings are free of cracks, rust or deformation, and verify the corrosion resistance of the material (such as sulfur resistance, acid and alkali resistance). ‌High temperature and high pressure adaptability‌: The structural stability and sealing surface durability of the valve are tested by simulating extreme environments in the laboratory (such as -196℃~800℃, 42MPa high pressure). ‌4. Action characteristics and response speed test‌
‌Opening and closing flexibility‌: Manually or automatically operate the valve disc to observe whether it rotates smoothly. If it is stuck or cannot be completely closed, it may be due to wear of the valve disc hinge pin or foreign matter. ‌Closing response time‌: Under reverse flow conditions, test the time from full opening to full closing of the valve disc. Damping structures (such as slow-closing auxiliary valves) can reduce water hammer impact, but it is necessary to ensure that the closing speed matches the system safety requirements. ‌ ‌5. Applicable scenario suitability assessment‌
‌Installation direction verification‌: The swing check valve can be installed horizontally, vertically or tilted, but when installed vertically, it is necessary to ensure that the medium flows from bottom to top‌.
‌Media compatibility‌: Select the valve disc material according to the medium type (such as fluid containing particles, corrosive liquid). For example, the medium containing solid particles should give priority to the metal sealing structure with stronger wear resistance‌.
‌6. Maintenance and economic analysis‌
‌Ease of disassembly and maintenance‌: The split valve cover design and standardized components can simplify the maintenance process and reduce the long-term use cost‌.
‌Life prediction‌: Evaluate the remaining service life of the valve by accumulating the operating time (such as 50,000 hours benchmark) and the degree of wear (such as pin shaft and sealing surface loss).