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1. Select a qualified hydrophobic valve. When selecting a steam trap, it is necessary to choose a qualified supplier and verify the tightness of the steam trap at regular intervals. 2. Strengthen the implementation of responsibilities for inspection and acceptance. An organizational structure for preventing and controlling internal valve leakage should be established, responsible persons should be assigned to ensure compliance with relevant standards, records of inspections and corrective actions regarding internal valve leakage should be kept, and strict controls should be applied during the inspection and acceptance process of valves. After valve maintenance, grinding, or repair, a professional should inspect the degree of fit between the sealing surfaces; if the quality of the maintenance is not satisfactory, rework must be carried out. 3. Install wall temperature sensors on the outer walls of the pipes before and after the hydrophobic valve, and then connect them to the DCS system. In this way, internal leakage at the hydrophobic gate becomes clear at a glance. It not only provides a basis for maintenance but also makes the leakage status of steam trap valves transparent, facilitating supervision and management of such leaks by technicians at all levels. 4. Standardize valve operation. During the startup and shutdown of the turbine, operators must strictly follow the regulations regarding the opening and closing of the drain valves, opening and closing them at the prescribed times. It is strictly prohibited to open these valves too early or close them too late, to avoid damage to the valves caused by excessive steam flow. When closing the valve manually, it must be closed tightly to prevent it from being washed away. When operating valves, try to avoid keeping them at a partial opening for long periods of time. For shut-off valves, they should in principle be either fully closed or fully open; a partial opening is not allowed, in order to prevent erosion of the valve’s sealing surfaces and resulting internal leakage. For thermal pipelines equipped with primary and secondary valves, in order to prevent internal leakage of the valves, the sequence of operation should be to open the primary valve first and then the secondary valve, using the secondary valve for throttling adjustments ； When shutting it down, close the secondary door first, then the primary door; this is done to protect the primary door ； For some butterfly valves, the position of the switch should be clearly marked on site; once these valves are closed fully, no further force should be applied to close them, as doing so will cause erosion of the valves ； When switching valves of different models, use the appropriate wrench or operate them by hand to prevent the valve from being damaged due to excessive force. 5. Regularly check the condition of the valves and tighten them promptly. After the unit is started, in addition to ensuring that all manual drain valves are tightly closed, for the electric drain valves, they should be manually closed once immediately after they have been closed electrically. Six hours (or 10 hours) after each drain valve has been closed, if there is a temperature indicator behind the valve, it is necessary to analyze whether the valve is leaking internally by checking the temperature of the pipes behind the valve; if there is no temperature indicator behind the valve, then an infrared thermometer can be used to measure the temperatures of the pipe walls before and after the valve, or the valve can be checked by touch to determine whether it is leaking internally.