Factors to Consider When Choosing Butterfly Valves

Butterfly valves provide bi-directional dead-end service in commercial and industrial service. To make your selection easier, NIBCO offers specification and submitter assistance. You also get the assurance of the NIBCO warranty, along with superior customer service expertise. Choose NIBCO for:

• Wafer lug or grooved end connections
• Press-to-connect ends selection
• Broad range of sizes
  
• Lug or wafer types
• Ductile iron, cast iron, CPVC materials
• Lead-free* selection
• Fire protection selection
• High performance selection

Keep reading for information on selecting the right butterfly valves for your next project.

Operating Life

Butterfly valves can provide many maintenance-free cycles and still accommodate "bubble tight" shut-off.

Pressure Drop

Energy costs go up with excessive pressure drop. The valve or valves are but one factor in a piping system that contributes to pressure drop. Of equal concern are these factors:.

• Flow area of piping.

• Friction loss against pipe walls.

• Friction loss against pipe walls.
  

Butterfly valves have flow characteristics three times better than globe valves and approximately 75% of an equivalent size gate valve.

Versatility
Butterfly valves can be used for on/off service and throttling/balancing. They are superior in "versatility" as compared to a gate or globe valve. Butterfly valves have a wider range of chemical resistance due to the trim options and choice of elastomer liners.

Weight
Installation dollars saved with lightweight butterfly valves as compared to heavyweight cast iron valves; i.e. a 10" butterfly may weight 55 pounds, whereas a 10" iron gate may weigh 490 pounds. This can be an important savings when it is calculated over an entire system. The heavier the system, the stronger the pipe hangers, and the more expensive they become. So, by considering the weight of a valve one can also reduce piping system costs.

Physical Size
Butterfly valves take up approximately 1/6 the space of a gate valve. Every cubic foot of a building costs money. 
I.E.: 10" butterfly is about 21" high and a 10" iron gate is about 43" high. 

Bubble Tight Shut-Off
Gate and globe (metal to metal) seats cannot provide bubble tight shut-off. Resilient seated butterfly valves are bubble tight by design.

Ease of Operation
Butterfly valves offer 1/4" turn (90 degrees) open to close. Gates and globes require multiple turns to open and close. Ease of opening or closing means that butterfly valves can employ less expensive operators. 

Cost
A butterfly valve is generally 40% the cost of an iron gate valve, not only in low initial costs, but in low installation costs as well.

Maintenance
Properly installed butterfly valves are virtually self cleaning and are less susceptible to failure due to trash material in the line.
For more information on Milestone Butterfly Valves, visit our website.