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Due to the influence of the medium being measured, blockages may occur in the pipes when using Siemens positioners. Below are several solutions available. 1. Medium scouring method: The Siemens actuator can utilize the scouring energy of the medium itself to wash away substances that tend to settle or cause blockages, thereby enhancing the valve’s resistance to blockages. 2. Change from straight-through to angular flow pattern: The Siemens positioner can convert the flow from straight-through to an inverted S shape. This is due to the complex flow path and numerous dead zones in the upper and lower chambers, which provide areas where the medium can settle. Angular connection: the medium flows as if through a 90-degree elbow, offering good scouring performance, a small dead zone, and ease of design into a streamlined shape. Therefore, when a slight blockage occurs with a straight-through control valve, it can be replaced with an angle valve. 3. Increase the gap: This applies to sleeve control valves used on steam pipelines. If the gap between the valve core and the sleeve is too small, or if different materials are used, heating may cause the valve to stick due to differences in expansion coefficients; therefore, it is possible to increase this gap appropriately during manufacturing. 4. Method of increasing the throttling gap: If 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, Siemens positioners can be equipped with throttling elements that have 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.