Product Name: Double Flanged Concentric Butterfly Valve
Design Standard: API 609
Body Material: ASTM A351 CF8
Size: DN100, 4 Inch
Pressure: PN16, Class 150 LB
End Connection: Flanged
Operation: Wormgear
The Wafer Concentric Butterfly Valve is engineered to provide a reliable seal against bi-directional pressure differentials, preventing backflow in systems designed for unidirectional flow. It achieves this through a tightly fitting seal, gasket, O-ring, and precision-machined components, with flat valve faces on both the upstream and downstream sides. The valve body features threaded inserts on both sides, enabling installation with two sets of bolts—without the need for nuts. This design allows for installation between two flanges using separate bolt sets for each flange, making it possible to disconnect one side of the piping system without affecting the other side.
Technical Specifications
» Size Range: 2-48 Inch (DN50-DN1200)
» Pressure Ratings: Class 150 LB, PN10, PN16
» Materials: GG25, GGG40, ASTM A216 WCB, A351 CF8, CF8M, CF3, CF3M
» Optional Seat Materials: Resilient NBR, EPDM, VITON
» Operation: Handle, Handwheel, Pneumatic, Electric
» End Connections: Wafer, Lug, RF Flange
» Design and Manufacture Standards: GB/T 12228, API 609
» Face-to-Face (End-to-End) Standard: GB/T 12221
» Flanged Connection Standards: ANSI B16.5, GB/T 9113
» Test and Inspection Standards: API 598, GB/T 13927
» Temperature Range: -29°C to 120°C
» Medium: Water, Gas, Oil, etc.
Concentric Lining Butterfly Valve
Concentric Lining butterfly valve adopts lining on all the parts that contact with medium inside of body, the stainless steel which is resistance of corrosion is used as stem and disc to ensure the corrosion resistance of different strong corrosive medium. The valve body and disc materials can be made of cast iron, carbon steel or stainless steel to ensure the bearing strength. Many kinds of soft sealing material such as NBR, EPDM or PTFE etc can be used as lining material to adapt to different corrosive medium or working temperature.

Structural Features
ISO 5211 Top Mounting

Different End Connections Available:

Pressure/Temperature Ratings Chart:

Source: https://www.kosenvalve.com/api-609-butterfly-valve-astm-a351-cf8-4-in-cl150-dn100.html