Newbie seeking help regarding butterfly valves
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What are the structural differences among the D314H, D342H, and D343H butterfly valves, and in what environments are they suitable for use? Any good suggestions for the design? I am working on a low-pressure flare gas pipeline – what valve model is suitable for it?
The D341H single-eccentric hard-sealed butterfly valve was developed to address the problem of compression between the butterfly disc and the valve seat in concentric butterfly valves. This led to the creation of the single-eccentric butterfly valve, whose structural feature is that the axis of the valve stem is offset from the center of the butterfly disc; as a result, the upper and lower ends of the butterfly disc are no longer the rotation axis, which reduces and alleviates the excessive compression between these ends and the valve seat. The D342H double-eccentric hard-sealed butterfly valve is the most widely used type of butterfly valve at present; it was developed as an improvement on the single-eccentric butterfly valve. Its structural feature is that the axis of the valve stem is offset from both the center of the butterfly plate and the center of the body. The effect of dual eccentricity enables the butterfly disc to quickly disengage from the valve seat once the valve is opened, significantly reducing unnecessary excessive compression and scraping between the butterfly disc and the valve seat, decreasing the opening force, minimizing wear, and extending the lifespan of the valve seat. The D343H triple-eccentric hard-sealed butterfly valve requires heat resistance; a hard seal is necessary, but it results in high leakage rates ； It requires zero leakage, but cannot withstand high temperatures. To overcome the contradiction of the double-eccentric butterfly valve, a third eccentricity was applied to the butterfly valve.
:lol Got it, thanks!
It is recommended to avoid using butterfly valves, as their service life is shorter than that of gate valves
That’s amazing. Are there any relevant materials? Including other types of valves?