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The process of operating the valve is also a process of inspection. The following precautions should be observed: 1. For high-temperature valves, when the temperature rises above 200°C, the bolts expand due to heat, which can reduce the sealing performance of the valve’s external sealing parts. In such cases, it is necessary to \"heat-tighten\" the bolts; however, this should not be done when the valve is in its fully closed position. To prevent the valve stem from getting stuck and making it difficult to open later. 2. During seasons when the temperature is below 0°C, for valves that are shut off for steam and water supply, it is necessary to remove condensate and accumulated water to prevent the valves from cracking due to freezing. Special attention should be paid to insulation for valves where water accumulation cannot be ruled out, as well as for valves that operate intermittently. 3. The packing gland should not be tightened too much; it should allow for smooth operation of the valve stem. The idea that the gland should be tightened as much as possible is incorrect; over-tightening accelerates the wear of the valve stem and increases the torque required for operation. 4. When abnormal phenomena are detected through listening, smelling, observing, and touching during operation, the operator must carefully analyze their causes. If the issue can be resolved by the operator themselves, it should be addressed promptly; if it requires the help of a repair technician, the operator should not try to fix it on their own to avoid delaying the repair process. 5. Operators should maintain a dedicated log or record book to keep track of the operation status of various valves, especially those that are important, high-temperature and high-pressure valves, as well as special valves. This includes information on the valve’s actuation mechanisms, any faults that occur along with their causes, the methods used to address them, and the parts that need to be replaced. Such information is undoubtedly very valuable for the operators themselves, maintenance personnel, and the manufacturers. Establishing dedicated logs with clear responsibilities helps to improve management. 1. Reasons for leaks at the gasket area: (1) The wrong type of gasket was used; it cannot withstand corrosion by the medium, nor can it handle high pressures or vacuums, high temperatures or low humidity. (2) Unstable operation leads to fluctuations in the valve’s pressure and temperature, especially fluctuations in temperature. (3) The compressive force of the gasket is insufficient, or there is no pre-tightening clearance at the connection. (4) Improper gasket assembly resulting in uneven stress distribution. (5) The machining quality of the static sealing surface is poor, with defects such as a rough surface, unevenness, transverse scratches, and misalignment of the sealing surfaces. (6) The static sealing surface and gasket are not clean, with foreign objects mixed in, etc. 2. Prevention and elimination methods: (1) The material and type of gasket should be selected appropriately based on the operating conditions. (2) Adjust carefully for smooth operation. (3) The bolts should be tightened evenly and symmetrically; a torque wrench should be used if necessary. The pre-tightening force must meet the specified requirements – it should neither be too low nor too high. There should be a certain pre-tightening clearance at the flange and threaded connections. (4) The gaskets should be aligned centrally during installation to ensure even stress distribution; overlapping gaskets or the use of multiple gaskets is not allowed. (5) If the static sealing surface is corroded, damaged, or of poor machining quality, it should be repaired and ground, and a coloring inspection should be carried out to ensure that the static sealing surface meets the relevant requirements. (6) When installing the gasket, care should be taken to keep it clean; the sealing surface should be cleaned with kerosene, and the gasket must not touch the ground.