Butterfly Valves
Overview
Butterfly Valves are quarter-turn rotary motion valves that use a disc to regulate flow. When the valve is closed, the disc blocks the passage; turning the shaft 90 degrees aligns the disc parallel to the pipeline, allowing full or near-full flow. Their compact design, relatively low cost, and wide size range make butterfly valves a staple in waterworks, HVAC, chemical processing, and other industrial applications.
Key Uses & Applications
Water & Wastewater
Municipal distribution lines, raw water intake, and treatment plants. Used extensively in both supply and effluent lines for on-off or throttling control.
HVAC & Building Services
Chilled water loops, cooling tower lines, and air handling systems. Lightweight valves reduce stress on pipelines; easy to automate for building management systems.
Industrial & Chemical Processing
Fluid regulation in petrochemical, refineries, and general process industries. Compatible with diverse media, from water and light chemicals to moderate slurry.
Power Generation
Cooling water systems, auxiliary service lines, and boiler feed loops (low to moderate pressure). Quick shutoff capabilities help minimize downtime.
Marine & Shipbuilding
Ballast, bilge, and seawater lines where compact valves and corrosion-resistant materials are essential.
Product Highlights
Quarter-Turn Operation
Fast open/close stroke—only 90° rotation from fully closed to fully open. Facilitates quick line isolation and simplified actuation.
Compact & Lightweight
Typically smaller face-to-face dimensions compared to gate or globe valves. Reduces load on piping systems and eases installation, especially in large diameters.
Multiple Body & Disc Materials
Body: Cast iron, ductile iron, carbon steel, stainless steel, or PVC/CPVC (for certain pressure classes). Disc: Stainless steel, ductile iron with rubber/vulcanized seat, or specialized alloys for abrasion/corrosion resistance.
Versatile Connection Styles
Wafer (sandwiched between two flanges), Lug (threaded inserts for end-of-line or isolation service), Double Flanged (fully flanged body for high-pressure or critical applications).
Wide Sizing & Pressure Ratings
Commonly from 2" (DN50) up to 48" (DN1200) or more. Pressure classes from PN6 / PN10 / PN16 up to Class 150, Class 300, and beyond, depending on design.
Throttling & Flow Control
Suitable for both on-off and modulating service. Minimal pressure drop when the disc is fully open.
Technical Specifications
| Valve Type | Butterfly Valve (Wafer, Lug, Double Flanged, etc.) |
| Size Range | 2" – 48" (DN50 – DN1200); larger sizes available |
| Pressure Ratings | PN6, PN10, PN16, PN25, Class 150, Class 300 (design-dependent) |
| Body Materials | Cast/Ductile Iron, Carbon Steel (WCB), Stainless Steel (CF8/CF8M), Alloy steels, or PVC/CPVC for low-pressure |
| Disc Material | SS304/316, Ductile Iron with EPDM/NBR seat, Bronze, Duplex Alloys, etc. |
| Seat/Seal | EPDM, NBR, PTFE, Viton, or metal seat for high-temp or abrasive service |
| Shaft/Bearing | Stainless Steel shaft, self-lubricating bearings or bushings |
| End Connections | Wafer, Lug, Double Flanged, Grooved End (special) |
| Leakage Class | Often meets ISO 5208, EN 12266, or API 598 standards |
| Actuation | Lever, Gearbox, Pneumatic/Electric/Hydraulic Actuators |
| Design Standards | ISO 5752, API 609, EN 593, AWWA C504 (waterworks) |
| Operating Temperature | -20°C to +200°C (material-dependent) |
Design & Performance Features
Center vs. Eccentric Disc
Concentric (Centered) Disc: Shaft passes through center of the disc. Typically for lower pressures (< PN16) or water lines. Single/Double/Triple Offset (Eccentric): Disc offset relative to seat center. Reduces seat wear, improves sealing under higher pressures or abrasive media.
Resilient or Metal Seat
Soft/Resilient Seat: EPDM, NBR, or PTFE seat for bubble-tight shutoff in water or mild chemical services. Metal-to-Metal: Withstands high temperatures and abrasive fluids; typical in double/triple offset designs.
Actuation Options
Manual Lever: Quick on-off for smaller diameters. Gear Operator: Common for medium to large valves, providing torque multiplication and more precise control. Pneumatic/Electric/Hydraulic: Automated for remote control and modulating flow.
Slim Face-to-Face
Minimal face-to-face dimension simplifies installation in tight spaces. Wafer and lug designs are especially compact, reducing pipeline weight and cost.
Low Pressure Drop
Minimal disc protrusion in open position. Good flow characteristics, beneficial in large-diameter lines.