What is a Triple Offset Butterfly Valve?
Apart from zero offset butterfly valve, the double or triple offset butterfly valve called high performance butterfly valve. There are three offsets in a triple offset butterfly valve or triple eccentric butterfly valve. Two of these factors affect the location of the shaft relative to the center line of the bore and the center line of the seat sealing surfaces. Another offset is the design in the axis of the seat cone angle. Triple offset valves have been around for more than 50 years, and their applications across a wide range of industries have evolved as well.
How Does a Triple Offset Butterfly Valve Work?
A triple offset butterfly valve's third offset, along with the two other eccentric shaft offsets, enables frictionless sealing of the disc against the seat. In metal seat designs, this seat design enables uniform sealing and an especially tight shutoff. The result is a lower torque, higher value alternative to metal seated valves.
When to Use Triple Offset Butterfly Valve?
Originally designed for water shut-off applications, triple offset butterfly valves are now common in extreme applications requiring bubble-tight shutoff, such as chemical processing. The innovative design of a triple eccentric butterfly valve gives it a distinct advantage over other types of butterfly valves, particularly double offset butterfly valves. Aira Euro Automation is a leading triple offset lug type butterfly valve manufacturer in India.
What are the Main Triple Offset Butterfly Valve Advantages?
The advantages of a triple offset butterfly valve are the conical sealing design, which results in repeatable sealing and extended valve life. A metal-to-metal seal ensures bubble-tight shut-off, zero leakage, and compatibility with corrosive media. Due to friction-free stroking, a lower torque-actuator can be used, which prolongs the valve's life. Plus, since there are no cavities between the sealing components, operators can expect zero clogging and therefore minimal maintenance.
What are the Main Triple Offset Butterfly Valve Disadvantages?
Triple offset butterfly valves eliminate some of the more common problems associated with traditional butterfly valves, including their inability to handle slurry applications, a lack of bubble-tight shut-off, and leak paths around the disc stem. However, they need to be removed from the piping for internal repairs and are relatively expensive compared to other types of valves. Their long service life and low maintenance credentials, however, make them an excellent investment.
What is the Typical Triple Offset Butterfly Valve Flow Direction?
These valves have an arrow on the body to indicate a preferred flow direction, but can also be used as bi-directional valves as long as the differential pressure is not high in the opposite direction of the arrow. Triple eccentric butterfly valves are a viable alternative to gate and globe valves since they work well as shut-off valves.
What is the Difference Between Double and Triple Offset Butterfly Valves?
The name implies that double offset butterfly valves have two stems offset from the center. Triple offset butterfly valves have three stems. Two of which are placed in the same position as the double offset butterfly valve, and the third is the seating surface geometry. This creates a cone-shaped gap between the disc and the seat. Double offset valves are used in similar industries as triple offset valves, except in more demanding applications. Friction occurs at the first 10° of opening and the last 10° of closing of double offset valves. The third offset keeps the disc and seat from touching until the last 1° of closing, resulting in virtually frictionless operation.
What are the Double Eccentric Butterfly Valve
Double eccentric butterfly valves, also known as high-performance butterfly valves, have the shaft-mounted slightly off-center from the pipe centerline, and the shaft is mounted behind the sealing band of the seat. The seat is a narrow band, clamped to the body, and must be resilient. At seating, the double eccentric butterfly valve is resilient enough to seal, and the disc only wipes the seat for a few degrees. As a result, the seats can last longer because there is less friction. As the disc is offset from the shaft, there is a lot of metal in the flow stream in the wide-open position and double-offset valves have a lower maximum capacity than flat-disc, non-offset valves.
General FAQ's About High Performance Butterfly Valve
What is a Triple Offset Butterfly Valve?
Apart from zero offset butterfly valve, the double or triple offset butterfly valve called high performance butterfly valve. There are three offsets in a triple offset butterfly valve or triple eccentric butterfly valve. Two of these factors affect the location of the shaft relative to the center line of the bore and the center line of the seat sealing surfaces. Another offset is the design in the axis of the seat cone angle. Triple offset valves have been around for more than 50 years, and their applications across a wide range of industries have evolved as well.
How Does a Triple Offset Butterfly Valve Work?
A triple offset butterfly valve's third offset, along with the two other eccentric shaft offsets, enables frictionless sealing of the disc against the seat. In metal seat designs, this seat design enables uniform sealing and an especially tight shutoff. The result is a lower torque, higher value alternative to metal seated valves.
When to Use Triple Offset Butterfly Valve?
Originally designed for water shut-off applications, triple offset butterfly valves are now common in extreme applications requiring bubble-tight shutoff, such as chemical processing. The innovative design of a triple eccentric butterfly valve gives it a distinct advantage over other types of butterfly valves, particularly double offset butterfly valves. Aira Euro Automation is a leading triple offset lug type butterfly valve manufacturer in India.
What are the Main Triple Offset Butterfly Valve Advantages?
The advantages of a triple offset butterfly valve are the conical sealing design, which results in repeatable sealing and extended valve life. A metal-to-metal seal ensures bubble-tight shut-off, zero leakage, and compatibility with corrosive media. Due to friction-free stroking, a lower torque-actuator can be used, which prolongs the valve's life. Plus, since there are no cavities between the sealing components, operators can expect zero clogging and therefore minimal maintenance.
What are the Main Triple Offset Butterfly Valve Disadvantages?
Triple offset butterfly valves eliminate some of the more common problems associated with traditional butterfly valves, including their inability to handle slurry applications, a lack of bubble-tight shut-off, and leak paths around the disc stem. However, they need to be removed from the piping for internal repairs and are relatively expensive compared to other types of valves. Their long service life and low maintenance credentials, however, make them an excellent investment.
What is the Typical Triple Offset Butterfly Valve Flow Direction?
These valves have an arrow on the body to indicate a preferred flow direction, but can also be used as bi-directional valves as long as the differential pressure is not high in the opposite direction of the arrow. Triple eccentric butterfly valves are a viable alternative to gate and globe valves since they work well as shut-off valves.
What is the Difference Between Double and Triple Offset Butterfly Valves?
The name implies that double offset butterfly valves have two stems offset from the center. Triple offset butterfly valves have three stems. Two of which are placed in the same position as the double offset butterfly valve, and the third is the seating surface geometry. This creates a cone-shaped gap between the disc and the seat. Double offset valves are used in similar industries as triple offset valves, except in more demanding applications. Friction occurs at the first 10° of opening and the last 10° of closing of double offset valves. The third offset keeps the disc and seat from touching until the last 1° of closing, resulting in virtually frictionless operation.
What are the Double Eccentric Butterfly Valve
Double eccentric butterfly valves, also known as high-performance butterfly valves, have the shaft-mounted slightly off-center from the pipe centerline, and the shaft is mounted behind the sealing band of the seat. The seat is a narrow band, clamped to the body, and must be resilient. At seating, the double eccentric butterfly valve is resilient enough to seal, and the disc only wipes the seat for a few degrees. As a result, the seats can last longer because there is less friction. As the disc is offset from the shaft, there is a lot of metal in the flow stream in the wide-open position and double-offset valves have a lower maximum capacity than flat-disc, non-offset valves.
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