Flanged butterfly valves are flanged butterfly valves connected by flanged connections.The flange butterfly valve installation method is different from the wafer butterfly valve. The flange butterfly valve has its own flange. When it is installed, it is not necessary to specially equip the flange plate. The flange on the valve body and the pipe flange can be directly bolted together. However, when installing a flanged butterfly valve, pay attention to the following points:
1. During installation, the end face between the butterfly valve body flange and the upper flange of the pipeline should be parallel, and no skew can occur. Otherwise, the flange joint may leak due to the bolt being not tightened.
2. When flanged butterfly valve is installed on the pipeline, gaskets should be added between the flanges at both ends of the pipeline and the flange of the valve body, but double gaskets cannot be used.
3. When the bolts are tightened symmetrically, the tightening force of the bolts at both ends of the flange connection must be uniform and consistent.
4. During installation, first install the bolts of the positioning holes on the butterfly valve to fix the position of the butterfly valve. In addition, when tightening the flange bolts, tighten them symmetrically and do not tighten the bolts one by one.
Flange butterfly valves have soft-seal flanged butterfly valves and hard-seal flanged butterfly valves. Usually soft seal flange butterfly valve is suitable for medium, fresh water, sewage, seawater, air, steam and other weak acid weak base media. Hard-seal flanged butterfly valves are suitable for corrosive fluid media such as water, weak acids, alkalis, air, steam, and oil.
Compared with the wafer butterfly valve, the flange butterfly valve has better sealing performance and is more suitable for a large-diameter valve. However, the use cost and price will be higher. The flanged butterfly valve has a longer structure and occupies more space for pipe installation.