In order to control the flow of a gas or liquid, engineers often use ball valves and butterfly valves. They are both quarter-turn rotary valves that are inexpensive and durable. At a wide range of temperatures, both are excellent for regulating flow. How do ball valves and butterfly valves differ?
The differences between them are subtle, but each has unique characteristics that make them ideal for specific applications. Both a butterfly valve and a ball valve can be beneficial for a project based on factors like pressure differences, seal quality, and the size of the supply pipe.
A ball valve consists of a floating ball and a hole running through it. When the valve is activated, the hole blocks partially block or completely opens the flow of liquid or gas. In applications involving gas flow, ball valves have several advantages, including a tight seal. They are often used in liquid or gas lines with diameters less than 6 inches. Despite high pressure on the supply side, ball valves offer almost no resistance when turned. There are some designs that provide no pressure drops. It is usually possible for ball valves to operate in temperatures between -30°C and 230°C. Ball valves come in several types, including:
- Full-port ball valves provide uninterrupted flow because the hole in the ball matches the pipeline. Different opening sizes do not cause friction loss in this approach.
- Reduced-port ball valves: The ball hole is slightly smaller than the pipe, which restricts flow. In addition to increasing flow velocity, this design makes the valve less expensive as well.
- A V-port ball valve has a V-shaped ball or seat. When the valve is activated, the small end opens first, allowing more stable flow. Typically, these valves are used in applications requiring more control or high velocity. Due to their robust construction, they can withstand higher velocities than other valves.
- The ball is anchored to the top and bottom of the trunnion ball valve. To prevent the ball from floating off and causing problems with the seating mechanism, this design is often required in large-scale or high-pressure applications. We are a ball valve manufacturer in India.
The butterfly valve is a lightweight valve that comes in one- and two-piece designs, named after its resemblance to butterfly wings. These valves have two pieces that fold inward to allow full flow and lie flat when closed. A disk is mounted on a shaft that rotates around the pipe in one-piece designs. A valve is activated by turning the disk to fully open or block the flow of gas or liquid through it. Wafer and lug butterfly valves are the most common types of butterfly valves. The main difference between them is how they are installed.
A wafer valve is a relatively standard and often less expensive valve than a lug valve. It is installed between two flanges with bolts, studs, and nuts. This design does not allow you to disconnect one side of the pipe, but wafer butterfly valves are a great choice if you do not need to disconnect one side of the pipe.
A lug butterfly valve is a less permanent fixture that uses threaded metal inserts instead of nuts in the bolt holes. Flanges are bolted separately on either side. You can disconnect one side of the piping system and leave the other untouched with this design.
Materials and maintenance are typically less expensive with these valves. In addition to being lighter, they are also faster to open and close than ball valves. Large-scale projects, such as municipal water systems and sewers, often use them. Water flow can often be controlled with butterfly valves in applications. When flow loss is not an issue, butterfly valves are excellent for controlling flow and pressure. A butterfly valve is also smaller than a ball valve, which is useful for projects requiring minimal space.
How Ball Valves Differ From Butterfly Valves
While ball valves and butterfly valves perform similar tasks, their similarities are limited. Both valves are:
- Great options for accurate fluid handling
- A quarter-turn rotary valve opens and closes by turning 90 degrees
- Affordable and long-lasting
- Made out of durable materials like cast iron and stainless steel
Flow is the primary difference between the valves. A butterfly valve drops pressure when part of the disk interferes with the flow. This is, of course, a disadvantage for applications requiring consistent or high pressure. Also, the incoming pressure from the supply side can make it difficult to operate the valve. Before a butterfly valve can function properly, a bypass valve may be needed to balance out the pressure. The ball valve, on the other hand, offers 100 percent flow. For projects that require higher pressure, it can be used.
The size of the application is another factor to consider. Ball valves typically become less cost-effective at around 6 inches in diameter due to their design. Butterfly valves are generally more economical at that point. In addition to being lighter, they tend to be more affordable. Their characteristics make them ideal for large-scale projects where flow control is not a major concern. Moreover, butterfly valves don’t trap fluids like ball valves, so they’re better for applications in food production, where residues may be hazardous.
Aira Euro Automation is a leading butterfly valve manufacturer in India.