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I. Cleaning method: The most common faults involve slag, rust, and debris in the pipelines causing blockages or jams at the throttle ports, guide areas, and balance holes on the lower valve cover; this leads to scratches and abrasions on the surface of the valve core and its guide surfaces, as well as indentations on the sealing surfaces. This often occurs in newly commissioned systems and in the early stages after major repairs. In such cases, it is necessary to remove the component for cleaning in order to get rid of debris; if the sealing surface is damaged, it should also be ground ； At the same time, open the bottom plug to flush out the debris that has fallen from the balance hole into the lower valve cover, and to clean the pipeline. Before putting it into operation, open the control valve fully; allow the medium to flow for a while before proceeding with normal operation. II. External flushing method: When using ordinary valves to regulate media that tend to precipitate and contain solid particles, blockages often occur at the throttling ports and guide areas; in such cases, flushing gas and steam can be supplied at the bottom plug of the lower valve cover. When the valve becomes clogged or stuck, opening the external gas or steam valve allows for flushing to be carried out without moving the control valve, thereby restoring normal operation of the valve. III. Method of installing pipeline filters: For small-diameter control valves, especially those with extremely low flow rates, the throttling gap is very small; therefore, there must not be any debris in the fluid. In the event of such blockage, it is best to install a filter on the pipeline before the valve to ensure smooth flow of the medium. For control valves used with positioners, when the positioner does not function properly, the most common fault is a blocked throttle in its air supply line. Therefore, when the locator is in use, it is necessary to properly manage the air supply; the common approach is to install an air filter and pressure regulator on the air supply pipeline before the locator. IV. Method of increasing the throttling gap: In cases where solid particles in the medium, or welding slag and rust that have been washed away in the pipes, cause blockages or jams due to their inability to pass through the throttling opening, it is possible to use throttling elements with a larger throttling gap – valve cores or sleeves with window-like or open-shaped throttling areas. Since the throttling area is concentrated rather than distributed circumferentially, such problems can be easily resolved. For single- or double-seat valves, the plunger-type valve core can be replaced with a valve core having a “V”-shaped port, or it can be changed to a cartridge valve or similar. For example, a chemical plant had a two-seat valve that would get stuck frequently; after it was recommended to switch to a sleeve valve, the problem was resolved immediately. V: Medium scouring method: Utilizing the scouring energy of the medium itself to wash away and remove substances that tend to settle or cause blockages, thereby enhancing the valve’s resistance to blockages. Common methods include: modifying it for use in a flow-closed configuration ； Use a streamlined valve body ； Place the throttle at the area most subject to erosion; when using this method, it is important to improve the erosion resistance of the material used for the throttle component. VI. Change from straight-through to corner method: The straight-through configuration involves an inverted S-shaped flow pattern, with a complex flow path and numerous dead zones in the upper and lower chambers, which provide areas for the deposition of the medium. Angular connection: the medium flows as if through a 90° elbow, resulting in good scouring performance, a small dead zone, and ease of designing it in a streamlined shape. Therefore, when a slight blockage occurs with a straight-through control valve, it can be replaced with an angle valve.