Concentric Butterfly Valve

Expanding Slab Gate Valve is a type of slide valve that utilizes parallel gate plates as its closing mechanism. These plates are equipped with a spreading mechanism to enhance functionality. The force pressing the plates against the valve seat is regulated by the medium pressure acting on either a floating gate plate or a floating valve seat. In dual gate flat gate valves, the inter-plate spreading mechanism provides additional pressing force. This valve is designed with innovative features including low operating torque, rapid actuation, minimal vibration, extended operational life, and enhanced safety. It is mainly used for the isolation or venting of gases and liquids in pipeline systems.

The DBB Plug Valve is a high-performance fluid control device. It adopts advanced track-guided technology to achieve low-torque opening and closing and zero-leakage sealing. This valve is specially designed for harsh working conditions and is suitable for key fields such as petroleum, chemical industry, power and long-distance pipelines. It can meet the complex working conditions such as high pressure, high temperature, corrosive media, and frequent operations. (also known as the general valve) is a high-performance fluid control device. It adopts advanced track-guided technology to achieve low-torque opening and closing and zero-leakage sealing. This valve is specially designed for harsh working conditions and is suitable for key fields such as petroleum, chemical industry, power, and long-distance pipelines. It can meet the complex working conditions such as high pressure, high temperature, corrosive media, and frequent operations.

The working principle of the three eccentric butterfly valve is based on its unique structural design, which achieves sealing and flow control functions through three eccentric distances: ‌Structural Design: ‌Three Eccentric Structure‌: The valve stem axis deviates from the center of the butterfly plate and the body center, and the rotation axis of the valve seat is at an angle to the axis of the valve body channel. This design enables the butterfly plate to form a wedge-shaped space with the valve seat when closed, achieving sealing through friction.‌ ‌Conical Sealing Surface‌: The periphery of the butterfly plate is machined into an external inclined conical surface, and the valve seat is an internal inclined conical surface, forming an elliptical contact surface. When closed, the butterfly plate achieves sealing through the asymmetric pressing force in the up and down directions, and the sealing becomes tighter as the pressure increases.‌ Working Mechanism: ‌Open State‌: The butterfly plate is separated from the valve seat, and the fluid passes through the channel; due to the eccentric design, during the opening process, the butterfly plate gradually detaches from the valve seat, reducing friction and operating torque.‌ ‌Closed State‌: The butterfly plate rotates 90° to contact the valve seat, forming a wedge-shaped space and achieving sealing through torque. ‌Flow Regulation‌: During the opening rotation of the butterfly plate, the valve's flow area gradually increases, reducing fluid resistance and improving the flow coefficient, achieving flow regulation. ‌Technical Advantages‌: Sealing Performance‌: The metal-to-metal hard sealing method can still maintain good sealing performance in high-temperature and high-pressure environments;‌ ‌Low Friction Operation‌: The eccentric design significantly reduces the operating torque and extends the valve's lifespan;‌ ‌Self-Locking Function‌: When closed, the butterfly plate becomes tighter under pressure, preventing the phenomenon of over-positioning.‌ This valve is widely used in the petroleum, chemical, and power industries, and common structural connection forms include double flange type, welding type, lug type, and socket type, etc.