The resilient seated butterfly valve is the most commonly butterfly valve. This butterfly valve comes with many different disc:NYLON COATED, EPOXY COATED, DUCTILE IRON, 316 STAINLESS STEEL AND CARBON STEEL BODY MATERIALS AVAILABLE
One piece dis/stem in high strength design. Available in options such as PTFE lined 316 stainless steel , Nylon 12 Coated 316SS or rubber covered with the covering extending on the stem sealing area. Unique heavy-duty square grooved "center lock" seat design virtually eliminates any seat movement during seating and unseating of the disc. Seat designs has continuous homogeneous that extends through the stem area and is flanged on the back of the seat.
Precision machined radius on the upper and lower disc hubs pressed against upper and lower seat sealing faces for achieving primary sealing between the disc and stem. The butterfly valve include a bi-directional U cup stem seal as well. Heavy duty two piece body with extended neck for 2" piping insulation. Standard coating is Nylon with two coats of hard, zinc rich epoxy for excellent corrosion resistance is optional. Two flange locating holes for sizes up to 12" for easy alignment of the butterfly valve during installation.
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Related recommendation:
DIN 3202 F4 Cast Iron Rising Stem Gate Valve