Leaks in solenoid valves after prolonged use require a comprehensive analysis of various factors, including seals, valve body, installation, media, operating environment, and electrical controls. Aging or damage to seals is a common cause. The sealing structure of a solenoid valve relies on rubber O-rings, gaskets, or shaft packing glands. These components gradually lose elasticity under prolonged exposure to high temperatures, high pressures, or corrosive media, leading to seal failure. For example, cracks in O-rings due to material aging or deformation of gaskets due to long-term compression can both cause leaks. In such cases, the solenoid valve needs to be disassembled to inspect the condition of the seals. If hardening, cracking, or wear is found, the seals must be replaced promptly, ensuring the new seal material is compatible with the media.
Accumulation of impurities inside the valve body or valve core jamming can also cause leaks. Particles, rust, or raw material debris in the media can enter the valve body, clogging the throttling or balancing orifices, hindering valve core movement or causing wear on the sealing surfaces. For example, impurities may prevent the valve core and seat from fully fitting together, creating a tiny gap that leads to leakage. At this point, the valve body needs to be disassembled, and the internal passages cleaned with compressed air or cleaning agent to remove impurities. The valve core and seat surfaces should be inspected for scratches or wear; if necessary, they should be ground, repaired, or replaced.
Improper installation is another common cause. If the sealing surface is not aligned according to the manufacturer's requirements during solenoid valve installation, or if the connecting threads are not tightened, localized stress concentration can occur, damaging the sealing structure. For example, gaps may appear at the connection between the valve body and the pipeline due to loose threads, or the connection between the solenoid head and the valve body may not be tightened, both of which can cause leakage. During troubleshooting, all connections should be checked to ensure that the threads are tightened and the sealing surfaces are flat and undamaged. If necessary, reinstall and tighten using a torque wrench according to specifications.
The characteristics of the medium have a significant impact on the sealing performance of the solenoid valve. If the medium temperature is too high, it may accelerate the aging of the seals; if the medium viscosity is too high, it may increase the resistance of the valve core movement, leading to wear on the sealing surfaces; if the medium contains corrosive components, it may directly corrode the valve body or seals. For example, in steam systems, high-temperature steam can cause rubber seals to harden and crack; in chemical processes, corrosive liquids can corrode metal valve bodies or seals. During troubleshooting, it is necessary to confirm whether the medium type, temperature, and pressure are within the rated range of the solenoid valve. If they are outside this range, a dedicated solenoid valve resistant to high temperatures, corrosion, or high pressure must be replaced.
Environmental factors should not be ignored. If a solenoid valve is exposed to humid, vibrating, or extreme temperature environments for extended periods, internal condensation may cause electrical short circuits, or vibration may cause components to loosen, leading to leaks. For example, if a solenoid valve used outdoors is not equipped with a protective cover, rainwater may seep into the valve body, corroding electrical components or seals; if a solenoid valve installed on vibrating equipment is not securely fixed, long-term vibration may cause threads to loosen or seals to shift. During troubleshooting, the installation environment of the solenoid valve should be checked to confirm whether moisture-proof and vibration-proof measures have been taken, and if necessary, the working environment should be improved or protective devices should be installed.
Electrical control faults can also indirectly lead to leaks. If the solenoid valve coil burns out due to moisture, overload, or unstable voltage, the valve core may malfunction, leading to leakage. For example, a short circuit or open circuit in the coil will prevent the solenoid valve from engaging, causing the valve core to remain in place and resulting in continuous leakage. During troubleshooting, use a multimeter to check the coil resistance to ensure it is within the normal range, and check if the power supply voltage is stable and if the wiring is loose or has poor contact. If the coil is damaged, replace it with a coil of the same specification and ensure reliable electrical connections.
