Butterfly Valves

The butterfly valve features a straightforward design and is suitable for low-pressure pipeline media. It operates by
rotating a disc, known as the closing piece, around a shaft that runs vertically through it to open and close the valve. Butterfly valves are versatile and can control the flow of a wide range of fluids, including air, water, steam, various corrosive substances, slurry, oil, liquid metals, and even radioactive materials. The valve primarily consists of a circular valve body, a stem or shaft, a disc, and a seat (seal ring) integrated into the body.

Different Types of Butterfly Valves

Lug Type Butterfly Valve

Dual Plate Wafer Type Check Valve

Wafer Type Butterfly Valve

Grooved Butterfly Valve

Manual Butterfly Valve

U Type Butterfly Valve

Gear Operated Butterfly Valve

Lever Operated Butterfly Valve

Butterfly Valves Dimensions and Info

Dimension	11/2"-48"
End Connection	wafer type, lug type, double flanged, U-section, grooved end
Body Material	gray iron(GG25), ductile iron(GGG40/50), cast steel(WCB), stainless steel(CF8,CF8M,CF3,CF3M)
Disc Material	ductile iron(nickle plated or nylon coated) caststeel(A216WCB) stainless steel(CF8,CF8M,CF3,CF3M) aluminium bronze(C954)
Seat Material	EPDM, Buna-N(NBR),PTFE, viton, metal seated
Stem material	SS410,SS416,SS304, SS316
Actuator	handle lever, worm gear, pheumatic actuator,chain operator
Standard	API 609, BS5155, MSS SP-67/68, EN593

What Is A Butterfly Valve Used For？

A butterfly valve is a versatile and efficient component commonly used in various industrial applications for controlling the flow of fluids. Its simple design allows for quick opening and closing, making it ideal for systems where rapid response is crucial. Butterfly valves are widely utilized in water treatment plants, HVAC systems, and chemical processing facilities, where they can manage the flow of air, water, steam, and corrosive substances.

In addition to their use in standard fluid control, butterfly valves are also effective in handling slurries, oils, liquid metals, and even radioactive materials, demonstrating their adaptability across different industries. The lightweight construction of butterfly valves makes them easy to install and maintain, reducing the overall cost of system operations.

Another significant advantage of butterfly valves is their ability to provide a tight seal, which minimizes leakage and enhances system efficiency. This makes them particularly valuable in applications where maintaining pressure and flow rate is critical. Overall, the butterfly valve’s combination of reliability, efficiency, and versatility makes it an essential choice for a wide range of fluid management needs in both industrial and municipal settings.

Butterfly Valves Installation

1.Attach the lever (for manual valves) or the hand-wheel (for gear-operated valves).

2.Rotate the lever or hand-wheel clockwise to ensure that the valve is completely closed. The disc should be aligned parallel to the ends of the pipeline.

3.If the disc is not properly aligned, for lever-operated valves, gently loosen the top plate by removing the bolts, then turn the lever clockwise until the disc is centered and parallel to the ends, and then re-tighten the top plate. For gear-operated valves, make adjustments using the hex nuts located on the side of the gearbox. Open and close the disc several times to confirm it operates correctly. If realignment is still needed, repeat the adjustment process.

QButterfly Valves Installation 2

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4.Begin the installation of the valve into the piping system. Note that "wafer" style valves should be positioned between flanges and secured with fully threaded studs, while "lug" style valves are fitted between flanges using small cap screws at both the inlet and outlet.

5.Prior to placing the valve, separate the mating flanges by 3/16" more than the valve’s face-to-face dimension to prevent distortion or damage to the sealing face of the seat.

6.Ensure that the faces of the pipe flanges are free from any contaminants, such as scale, metal shavings, or welding debris.

7.With the disc closed, carefully insert the valve between the flanges, aligning and centering it properly. Accurate alignment between the upstream and downstream pipe ends is crucial for ensuring smooth operation of the valves.

QButterfly Valves Installation 3

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8. While gradually removing the flange spreader and verifying that the valve is centered to theflanges, secure by hand-tightening flange bolts.

9. Open the valve slowly to the full open position to assure free unobstructed disc movement and thatthere is no contact with the piping or mating flanges. Note that disc interference may result whenvalves are installed in pipelines having smaller than normal inside diameters, such as heavy wall pipe,plastic-lined pipe, as-cast flanges or reducing flanges. Interference can also occur when connectingdirectly to a swing check or silent check. Suitable corrective measures must be taken to remove theseobstructions, such as taper boring the pipe, or installing a spacer or spool piece.

10. After proper operation is verified, flange bolts should then be tightened, using a star orcrisscross pattern to evenly load the bolts, to the torque values shown below in table 1.

11. Pressurize piping to valve and inspect for leakage. If leakage is observed, tighten bolts usingcross-over pattern, increasing torque until leak stops. Note that recommended torques are made withoutwarranty. Installer must verify proper strength bolts for applications. Bolts should be clean andun-lubricated.