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When an electric control valve leaks during use, how should we deal with it? Here are five solutions to address leakage in electric control valves: One of these solutions is to use a lens gasket for sealing. For the sealing of the upper and lower covers, as well as between the valve seat and the upper and lower valve bodies, if a flat-seal design is used, its sealing performance is poor under high temperatures and pressures, leading to leakage. In such cases, using a lens gasket for sealing in the electric control valve can yield satisfactory results. One of the five solutions to external leakage in electric control valves is to change the flow direction. The method of placing P2 at the valve stem end can be used; when △P is high and P1 is also high, sealing P1 is clearly more difficult than sealing P2. Therefore, electric control valves can employ the approach of changing the flow direction, by moving P1 to the valve stem end and P2 to the other end – this is particularly effective for valves that operate under high pressures and large pressure differences. For example, in bellows valves, it is usually necessary to focus on sealing P2. One of the five solutions to external leakage in electric control valves is the use of additional packing. Typically, a double-layer or multi-layer mixed packing system is employed, with the number of sealing gaskets increased simply, for example from 3 to 5, in order to improve the sealing performance of the valve stem; however, this approach does not provide very significant leakage prevention effects for electric control valves. The method of adding sealing grease as one of the five solutions to external leakage in electric control valves: This approach is applicable to valve bodies that have not yet had sealing grease applied; by adding sealing grease, it is possible to improve the sealing performance of the valve stem. When performing regular maintenance on electric control valves, applying additional sealing grease is also one of the necessary maintenance procedures. One of the five solutions to external leakage in electric control valves is to replace the graphite packing. The widely used PTFE packing is suitable for operating temperatures within the range of -20 to 200°C; when the operating temperature varies significantly between these limits, the sealing performance of the electric control valve deteriorates markedly, and it ages quickly with a short lifespan. It is recommended to use flexible graphite packing here, as it can overcome the difficulties that perfluoroelastomer packing cannot handle, and it has a long service life, thereby enhancing the reliability of the seal. Many factories have completely replaced the PTFE packing with graphite packing, and even newly purchased control valves have their PTFE packing replaced with graphite packing before being put into use. However, graphite fillers also have a drawback: they exhibit a large hysteresis, and in some cases crawling behavior occurs as well. Therefore, manufacturers and users must take this into consideration when designing and installing electric control valve systems. The five solutions mentioned above for leakage in electric control valves are intended to provide some assistance to manufacturers and users of such valves when dealing with leakage issues.