Technical Insights from Shanghai Songjiang Shock Absorber Group Co., Ltd.
In our ongoing effort to share industry expertise on rubber joints and piping components, we present this concise guide explaining the difference between butterfly valve flanges and ordinary flanges — made crystal clear with one illustrative drawing.
What is a Butterfly Valve Flange?
The butterfly valve flange, also known as the lug-type flange or special flange for wafer butterfly valves, is specifically designed for installation with wafer-style butterfly valves in piping systems.
Key Differences Between Butterfly Valve Flanges and Standard Flanges
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Inner Diameter:
The most critical distinction lies in the flange’s inner diameter. The butterfly valve flange features an inner diameter precisely matched to the nominal diameter of the butterfly valve. This flange includes a special groove at the back designed to insert the connecting steel pipe securely, ensuring an optimal sealing effect for the butterfly valve. -
Sealing Performance:
Using a standard flange with a butterfly valve will compromise the sealing integrity, whereas the dedicated butterfly valve flange maintains tight sealing due to its tailored inner diameter and groove design. -
Other Dimensions:
The outer diameter, thickness, center-to-center bolt hole spacing, and bolt holes on the butterfly valve flange are identical to those on a standard flange of the same nominal size, allowing for easy installation. -
Bolts Used:
Butterfly valve flanges use double-headed bolts, and the choice of bolt material and type varies depending on the operating temperature and conditions.
Summary
The butterfly valve flange is a specially engineered flange to match wafer-style butterfly valves, ensuring optimal sealing and secure pipe connections. Its precise inner diameter and groove distinguish it from ordinary flanges, which lack this design feature and may cause leakage issues.
If you need, we can also provide detailed drawings, installation guides, or product specifications related to butterfly valve flanges and compatible rubber joints. Feel free to ask!
