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1. Impact on the safe production of thermal power plants: Safe production is of utmost importance in the operational activities of thermal power plants; without it, the continuity and efficiency of economic operations cannot be ensured. From the perspective of safe operation in power plants, internal leakage in valves prevents the isolation of faulty equipment during operation, as safety measures cannot be properly implemented. This poses a serious threat to the safety of maintenance personnel. For example, when maintaining feed water pumps, it is necessary to drain all water from the system and reduce the pressure to 0 MPa; moreover, the electric valves at the inlet and outlet of the feed water pumps must be tightly closed. Otherwise, if there is still pressure in the system while the maintenance personnel are disassembling the valves, serious consequences can occur. 2. Impact on the economic operation of thermal power plants: (1) Increased steam and water losses. Internal leakage in the valves causes steam and water loss within the unit; the more valves have internal leakage, the greater the loss of steam and water. (2) Thermal efficiency decreases. The working fluid, after being heated and pressurized, is directly leaked into the drain (or atmosphere) without being utilized. (3) Unit efficiency decreases. The high-temperature, high-pressure working fluid is discharged directly into the condenser without being utilized, resulting in an increased thermal load on the condenser, a drop in the unit’s vacuum, and a significant reduction in the efficiency of the turbine. For example, internal leakage in the bypass valves or drain valves of a turbine steam system has a significant impact on the economic operation of a power plant. (4) The increase in the number of internally leaking valves leads to higher costs for valve repair, grinding, and replacement. (5) The unit’s make-up water rate increases. Valve leakage causes water loss, preventing the unit from operating efficiently; it is necessary to replenish water into the system, which increases the rate of water supply to the unit.