Why can’t I see the gasket between the two flanges when installing a butterfly valve?
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Why can’t I see the gasket between the two flanges when installing a butterfly valve?
Gaskets are not required when installing butterfly valves, but it should be noted that butterfly valves with a diameter of DN200 or larger must use butterfly valve flanges.
What does \"butterfly valve flange\" mean? I’ve never seen it before
Wafer-type soft-seal butterfly valves generally come with gaskets; they can be used without them or with them, and the issue of aging needs to be taken into consideration. Flanged butterfly valves require gaskets to be used
It has been discussed before; please refer to http://bbs.hcbbs.com/thread-443431-1-2.html and http://bbs.hcbbs.com/thread-275788-1-1.html
Flanges specifically designed for butterfly valves, which are different from ordinary flanges
When installing wafer butterfly valves, necked weld flanges should be used; SO flanges cannot be employed, as this will prevent the butterfly disc from opening fully
The seat of a butterfly valve is usually fitted by embedding it; it is better not to attach it directly to the valve body, especially in the case of large-diameter valves. Sometimes, twisting of the seat occurs after the flanges are tightened
I agree with the view from the fourth floor: butterfly valves do not require gaskets because they have a rubber seal ring that folds inward from the outside. If such a seal ring is not present, then gaskets are necessary.
:Lol, it seems I really need to study hard then
Generally, butterfly valves do not require gaskets. But a check valve must be installed.
The butterfly valve already has rubber gaskets. This is used in conjunction with butt flanges.
In areas where butterfly valves are used, the pressure is generally not high. The medium isn’t very dangerous either.
Clamped butterfly valves use a rubber flange as the sealing surface, so no additional gasket is required; however, the butterfly valve’s flange must be taken into consideration, as the rubber sealing surface on these valves is smaller than that on ordinary flanges, making sealing more difficult. Flanged butterfly valves do not have rubber sealing surfaces, so gaskets must be used for sealing.
I think it’s best to use gaskets or seals for both wafer-type and flanged butterfly valves; however, if the diameter is 50 mm or less, gaskets or seals may not be necessary
Under normal low pressures, if the wafer butterfly valve is equipped with a soft seal, gaskets are not required. If gaskets are used, it is necessary to check whether the part of the soft seal that protrudes is long enough and whether there is sufficient overlap with the new gasket; if there is only a small amount of overlap and the thickness is considerable, then the sealing effect will be worse.
Under normal low pressures, if the wafer butterfly valve is equipped with a soft seal, gaskets are not required. If gaskets are used, it is necessary to check whether the part of the soft seal that protrudes is long enough and whether there is sufficient overlap with the new gasket; if there is only a small amount of overlap and the thickness is considerable, then the sealing effect will be worse.