Time：2021-03-17 14:04 Browse：
1.Cleaning method
The welding slag, rust and residuum in the pipeline are blocked or stuck in the throttle orifice, guiding position and the balance hole of the lower valve cover, causing the spool surface, guiding surface to produce strain and scratch, sealing surface to produce indentation, etc. This often occurs in the new operation system and the initial operation after overhaul. This is the most common breakdown. In this case, must be removed for cleaning, get rid of slag, such as sealing surface damage should also be grinding; At the same time, open the bottom plug to flush away any residue that has fallen into the lower cover from the balance hole and flush the line. Before put into operation, let the regulating valve fully open, the medium flow after a period of time into normal operation.
2.External flush method
For some easy to precipitate, containing solid particles of the medium with ordinary valve regulation, often in the throttle orifice, guide plug, can be under the cover of the bottom plug outside flushing gas and steam. When the valve is blocked or stuck, open the external gas or steam valve to complete the flushing without moving the regulating valve and make the valve run normally.
3.Install pipe strainer method
For small diameter control valve, especially the ultra-small flow control valve, its throttling gap is particularly small, medium can not have a little slag. In this case, it is best to install a filter on the pipe in front of the valve to ensure the smooth passage of the medium. With the use of positioner regulator, positioner work is not normal, its gas throttle plug is the most common fault. Therefore, when working with positioner, it is necessary to deal with the air source. The usual method is to install the air filter pressure reducing valve in the air source pipeline before the positioner
4.Increase throttling gap method
Solid particles such as the medium or washed off in pipe welding slag and rust due to pass the throttle mouth such as congestion, jam, such as fault, can convert the throttle gap bigger throttle piece - throttling area of a window, open the valve core and the sleeve, rather than the circumference of a circle because of the throttling area of concentration distribution, fault can easily be ruled out. If it is single, two - seat valve can be changed to the plunger - shaped spool "V" shape of the spool, or change to sleeve valve. For example, a chemical plant had a two-seat valve that was often stuck, and the problem was solved immediately after a sleeve valve was recommended.
5.Dielectric scour method
Using the medium of its own erosion energy, erosion and take away easy precipitation, easy to plug things, so as to improve the valve blocking function.
Common methods are：①Use as a closure；②Use streamlined valve body；③The orifice is placed in the place where the erosion is most serious.
6.Straight through to angular method
The direct flow is inverted S flow, the flow path is complex, the upper and lower cavity dead zone, for the precipitation of the medium provides a place. Angular connection, medium as through 90℃ elbow, erosion performance, small dead zone, easy to design into a flow line. Therefore, the use of a straight through valve to produce a slight blockage can be changed to Angle valve use.