The instructions on, adjusting valve
Regulating valve instructions 1. Large opening working life extension method to adjust the start valve as far as possible on the biggest opening work, such as 90%. So, cavitation and erosion damage on the valve core head. As the valve core damage, traffic increases, the corresponding valve closed again a bit, so constantly, gradually close, make whole all make full use of the valve core. Work at the same time, the big opening the throttle gap is big, erosion is abate, this is the start valve opening in the middle and small open degree on the working life of 1 ~ 5 times above. If a chemical plant using this method, increased the service life of the valve 2 times. 2. Working method of the valve opening to improve life increase with the decrease of S after consumption of orifice throttling pressure drop; Close the series manual valves on the pipeline, to adjust the opening of the valve to obtain ideal job. At the start valve to choose when you are working in a small open degree, using this method is simple, convenient and effective. 3. Narrow diameter increase the job opening life method through minish the adjustment valve diameter to increase job opening, the concrete measures are: (1) in one of a small caliber valve, such as DN32 into DN25; (2) does not change the valve body, replace the valve seat of the diameter of the valve core valve seat. If a chemical plant overhaul will throttle dgl0 replacement for dg8, life is doubled. 4. Transfer damage position to improve the method of life destroyed place transferred to a secondary position, in order to protect the valve seat sealing surface and the surface of the throttle valve core. 5. Growth throttling channel to improve life growth throttling channel is the most simple and thicken the valve seat, valve seat hole growth, forming a longer throttling channel. 6. Change to improve life flow towards open type flow, cavitation, erosion, the main effect on the seal, valve core roots and valve core damage to the valve seat sealing surface soon. Flow towards closed closed type flow, cavitation, erosion effect after the throttle valve seat sealing surface, under the protection of the sealing surface and the valve core roots and prolong the life span. 7. Method of use special materials to improve life for cavitation resistance ( Destruction shape such as honeycomb dot) And wash ( Streamlined small groove) Use of cavitation and erosion resistance, special material to make the throttling parts. 8. Change adjustment valve structure improve life method to change the valve structure or choose has a longer service life of the way to achieve the purpose of life, if choose multistage type valve, anti cavitation valve, corrosion resistance, etc. Regulating valve installation process should pay attention to the following questions: ( 1) Regulating valve before installation, must be carefully remove the dust accumulated by valve door during storage, during the installation process will keep clean. Because the dust impurities will make the valve seat and the internal parts damaged. In order to protect the clean, usually in the incomplete opening flange end plate. ( 2) Regulating valve is installed, the arrow on the valve body shall be consistent with the medium flow direction. ( 3) Regulating valve is a precision component, if they are stress of the pipe deformation, will damage the normal work. Therefore, flange and pipe installation should be vertical and position accurately in order to avoid deformation of the pipeline. Wells and pipelines to the appropriate support to prevent it happen in valve door weight under the action of bending deformation. ( 4) When regulating valve and pipe welding must be especially careful. If regulating valve and pipe welding not enough attention, failed to eliminate stress, will produce deformation. Welding, must strictly avoid welding slag splash into the valve gate, the existence of welding slag detrimental to the performance of the valve gate, if the splash splashing on the valve core directly, light directly affect the action of regulating valve, or damage to the valve core and valve seat. ( 5) Pipeline during pressure test and blow, regulating valve should be removed, with the corresponding straight pipe connected to prevent welding slag, iron chips sundries stuck in between the valve core and valve seat. Remove the regulating valve opening flange end applications of plastic sheeting bandage firmly.