BUT-WELDED END TRIPLE OFFSET BUTTERFLY VALVE

A butterfly valve is a type of valve commonly used to regulate or isolate the flow of a medium within a pipeline. The primary mechanism of a butterfly valve consists of a disk that rotates around an axis to open or close the flow passage. When the valve is in the open position, the disk is perpendicular to the flow, allowing the medium to pass freely. When the valve is closed, the disk is rotated to a position that blocks the flow.

The term "triple offset" refers to three key design features that enhance the valve's sealing performance and longevity:

First Offset: The centerline of the disc is offset from the centerline of the shaft. This allows for the disc to rotate rather than slide against the seat, reducing friction and wear.

Second Offset: The axis of the seat is offset from the valve body. This ensures that the sealing surfaces only come into contact when the valve is fully closed, which reduces wear over time.

Third Offset: The sealing surface is designed at an angle to the plane of the valve body, improving the effectiveness of the sealing mechanism.

These offsets combine to produce a valve with tight, reliable sealing, low operating torque, and minimal wear. The "but-welded end" designation refers to the way the valve is connected to the pipeline—by welding the valve’s ends directly to the pipe, ensuring a more secure and leak-proof connection than other methods like flanged or threaded connections.

The operation of a but-welded end triple offset butterfly valve relies on its unique design that minimizes friction and wear while providing a tight seal. Here is how it works:

Opening: When the actuator is engaged, the shaft rotates, causing the disc to pivot. Due to the first offset, the disc moves away from the seat, allowing the medium to flow freely through the valve. This offset prevents the disc from scraping or rubbing against the seat, reducing wear.

Closing: As the actuator continues to rotate, the second and third offsets come into play. The disc is gradually brought into contact with the seat, but only at a precise angle, which ensures a tight seal without excessive friction. The design of the valve also allows for a metal-to-metal seal, making it ideal for high-pressure and high-temperature applications.

Sealing: The third offset is key to the triple offset butterfly valve's sealing ability. This feature helps create a tight seal by forcing the disc to maintain an optimal position relative to the seat, which prevents leakage even under extreme conditions.

The combination of the three offsets results in a valve that operates with low torque, providing ease of operation while ensuring durability, minimal wear, and tight sealing.

But-welded end triple offset butterfly valves offer several significant advantages over other types of valves:

Leak-proof Design: The but-welded end connection, along with the triple offset design, creates a highly secure and leak-proof connection, which is especially important in high-pressure and critical applications where leaks are unacceptable.

Low Operating Torque: The triple offset design reduces friction and wear, which results in lower operating torque. This allows for easier actuation, whether manually or through a power actuator.

Durability and Longevity: With minimal contact between the sealing surfaces during operation, these valves have a longer operational life compared to other butterfly valves. The triple offset design minimizes seat wear and prolongs the life of the valve.

Versatility: These valves are available in a wide range of materials and sizes, making them suitable for a variety of applications, including high-pressure, high-temperature, and corrosive environments.

Reduced Maintenance: Due to the reduction in friction and wear, the but-welded end triple offset butterfly valve requires less frequent maintenance, which can reduce overall operational costs.

Compact Design: The butterfly valve's compact design allows for easy installation and minimal space requirements within the pipeline, which is beneficial in situations where space is limited.