【 Weak current College 】 control valve common troubleshooting methods (2)

Second, the control valve is often stuck or blocked-proof (cards) (6)
1) cleaning method
Pipeline of welding slag, rust, slag, etc. in throttle mouth, steering parts, valve cover balance hole caused blockage or jammed to spool surfaces, guiding surfaces produce injury and sealing surface scratches, indentation, and so on. This often occurs in the new operation system and commissioning initial overhauled. This is the most common fault. In such circumstances, it must be working on cleaning, get rid of the residue, such as sealing surface injuries should also be lapping at the same time open the bottom plug to come off from the balance hole fall into the following cover of slag, and on a rinsing pipes. Commissioning, control valve fully open, media flows for a period of time and then into normal operation.
2) external scour method
On some easy precipitation, and contained the solid particle medium using ordinary valve regulation, often in throttle mouth, oriented Department blockage, bottom plug under the bonnet at external scour gases and steam. When the valve have blocked or stuck, open external gas or vapor valves, you can still control valve complete washing the valve correctly.
3) installation of pipeline filter method
On small-calibre regulator, especially super small flow control valve, the throttle gap-small-, medium cannot have a little bit of slag. In such circumstances, it is best to block valve on the pipeline before the installation of a filter, to ensure that the media pass. Belt positioner used control valve, the Locator is not working properly, its pneumatic throttle mouth jam is the most common fault. Therefore, when you work with Locator, you must handle the gas source, usually is in front of gas pipeline Locator to install air filtering pressure relief valve
4) increase the throttle interval method
If the medium solids or piping is washed off of welding slag and rust on the result of a throttle mouth causing blockage,stuck, failure, instead of throttling gap of throttling element — cutting area to open the window, open the valve core, sleeve class because the throttling area focus instead of the circular distribution of the fault can be easily excluded. If you are single and two-seater valve to piston-shaped cartridge to "V"-shaped mouth spool, or into a sleeve valve and so on. For example, a chemical factory has a two-seater valve often stuck, it is recommended to use the sleeve valve, the problem resolved soon.
5) media scour method
Use the media's own wash away energy, erosion and sedimentation, easy plug easily, thereby increasing the valve-proof function. Common methods are: ① converted stream closed-use; ② ③ adopt streamlined body; the throttle mouth over the erosion of the most powerful Office, using this method it is necessary to pay attention to improving the throttling element material resistant to erosion.
6) passthrough to angle method
Pass-through to pour S flow, flow road complex, upper and lower dead-cavity, media offer of precipitation. Angle-shaped connection, media like through the 90 ° elbow, brushing performance good, the dead zone is small, easy to design a streamlined. Therefore, use a pass-through of regulating a slight plug can be changed to use angle valve.