Electric pneumatic - valve problem summary

Electric pneumatic control valve is an important execution units in industrial automation process control instrumentation. As in the field of industrial automation degree is higher and higher, is being more and more application in the field of all kinds of industrial production. Compared with traditional pneumatic pneumatic - valve has obvious advantages: energy saving (electric pneumatic regulator Only electricity when at work) , environmental protection, No carbon emissions) Fast installation, convenient, No need for complicated pneumatic pipe and pump stations) 。 Here is a simple sum up some common problems. Why can't a double seal valve used as a cut-off valve? Two-seater valve core has the advantage of force balance structure, allow the pressure difference is big, but its disadvantage is that the two seal face not good contact at the same time, cause leakage. If it is used to cut off at artificially, mandatory, obviously the result is bad, even as it made many improvements ( Such as double sealing sleeve valve) It is not desirable. Why straight trip held in pneumatic control valve performance is poor, quarter-turn valves prevent performance is good? Straight travel is vertical throttling valve core and the medium is horizontal, cavity flow is bound to turn down turn, make valve flow becomes quite complex ( Shapes such as 'S' type) 。 In this way, there is a lot of dead zone, provide the space for medium of precipitation, in the long term, causing congestion. Quarter-turn valves throttling direction is horizontal, flow into the medium level, level, easy to take unclean medium, at the same time, simple flow, precipitation medium space is little, so quarter-turn valves prevent performance is good. Why desalting water use line with rubber butterfly valve, fluorine-butterfly short service life of the diaphragm valve? Desalted water medium containing low concentration of acid or alkali, they have larger corrosion in rubber. Rubber corrosion performance for expansion, aging, low intensity, in line with rubber butterfly valve, diaphragm valve use effect is poor, its essence is the rubber is not caused by corrosion. After the rubber diaphragm valve to improve the corrosion resistance of good fluorine-butterfly diaphragm valve, but fluorine-butterfly diaphragm valve diaphragm and yield to fold up and down and were broken broken, mechanical damage, the shorter the life of the valve. Now the better way is special ball valve, water treatment it can use to 5 ~ 8 years.