ASTM A216 WCB Wafer Butterfly Valves, 20 Inch, 150 LB, Gear

Dec 23, 2025

Product Name: ASTM A216 WCB Wafer Butterfly Valves, Metal Seal
Type: Triple Offset Butterfly Valve
Body Material: ASTM A216 WCB, Carbon Steel
Size: 20 Inches, DN500, 500 mm
Pressure: Class 150 LB, PN20
End Connection: Wafer
Operation: Gear Operated
Temperature Range: -196°C to 550°C

We offer a comprehensive range of Triple Eccentric Butterfly Valves in a wide variety of pressure classes, body styles, and materials to meet critical process requirements across industries such as hydrocarbons, power generation, chemicals, and fertilizers. The product range includes valves in ASME pressure classes up to Class 600, with sizes up to 64 in. (1600 mm), manufactured in carbon steel, stainless steel, and alloy steels, and suitable for operating temperatures up to 538 °C (1000 °F). Valves in higher pressure classes, larger sizes, and alternative materials are available to meet specific customer requirements. The range also includes valves designed for cryogenic service. All metal-seated valves conform to API 609. Triple Eccentric Butterfly Valves are truly bi-directional and provide high-integrity sealing performance. All machining operations are carried out on advanced 5-axis machining centers, and customized welding machines are employed to ensure consistent quality and precision in manufacturing.

Technical Specification

» Product: Triple Eccentric Butterfly Valve
» Size Ranges: 2-64 Inch (DN50-DN1600) (Larger sizes upon request)
» Pressure Ratings: Class 150-600 LB (PN10-PN100)
» Body Materials: Carbon Steel (ASTM A216 WCB), Stainless Steel (ASTM A351 CF8, CF8M, CF3, CF3M), Low-Temperature Carbon Steel (ASTM A352 LCB, LCC)
» Shaft Material: 17-4PH, SS410, XM-19
» Seat Material: Fully metal seat, SS + Graphite Seat
» Operation: Handle, Worm gear, Pneumatic, Electric
» Temperature Range:
Metal Seat: -29°C to 425°C
Metal Seat (Cryogenic): -196°C to 121°C
» Ends Connections: Wafer, Lugged, Double Flanged, Butt Weld or Grooved
» Actuations: Manual, Pneumatic, Electric, Hydraulic, Counterweight, Electro-hydraulic

Product Features

» Lockable lever
» Easy site maintenance
» Ease of automation
» Positive, tight shut-off
» Optional top flange in accordance with ISO 5211
» Suitable for both gaseous and liquid services
» Wide range of body and trim materials for various service media
» Designed and manufactured in accordance with: ISO 5752, BS 5155, API 609, MSS SP-68, ASME B16.10, ASME B16.5, DIN 3202

Triple Offset Butterfly Valve

Triple offset metal sealing butterfly valve uses the three eccentric structure with multi-layer metal seal or pure metal sealing ring, different sealing materials are being used according to the different temperature request from end user.The structure of valve sealing ring that was formed after machining for triple eccentric butterfly valve is oblique cone type, the purpose of which is to let the disc open in a subtle angle and seat sealing surface can be completely separated from the sealing surface of disc, thus to reduce the friction of sealing surface during the open and close.

Triple Offset Frictionless Design

Offset 1: Offset for seat seal and the rotation center of stem.
Offset 2: Center of pipe and disc.
Offset 3: Seat sealing angle center line and flow passage center.
The triple offset of butterfly valve ensures the valve disc is completely separated from seat sealing surface while open in a slightly angle which could reduce the friction of sealing surface during open and close and opening torque as well as prolong the service life of the sealing surface.
Our metal sealing butterfly valve adopts multi-layer sealing ring to achieve the valve seal, the multi-layer seal ring is generally made of stainless steel and graphite combination The pure metal sealing can be used for special medium or high temperature.

Seat Structure

Low Operating Torque: Our butterfly valves combine three offsets. Standard sealing is graphite + metal. Optional PTFE + metal combinations are available for different temperatures and media, using flexible laminated metal and graphite to ensure a tight, uniform seal and reduce operating torque.
Zero Leakage: Laminated seal rings are self-aligning, allowing the valve to meet zero leakage per API 598.
Fire-Safe Design: Standard valves are not soft-seated and meet API 607 fire-safe requirements.
Anti-Blowout Shaft: Double anti-blowout design meets API 609 and ASME B31.1.
Top Retention: Packing gland follower retains the stem.
Bottom Retention: T-shaped collar prevents stem blowout.