Introduction to double-eccentric PTFE-sealed butterfly valve

Basic definitions and structural characteristics

The double-eccentric PTFE-sealed butterfly valve is a type of valve that uses a disc-shaped opening and closing element to reciprocally rotate about 90° to open, close, and regulate the fluid passage. It has the following structural characteristics:

• Single-elastic PTFE valve seat: It can maintain a reliable seal without the use of additional sealing rings or metal components; it can maintain a bidirectional leak-free seal; the sealing design automatically compensates for changes in operating temperature and pressure; it can also reduce maintenance and extend the service life.

• Offset valve stem and eccentric butterfly plate: When opening or in any position, there is no contact between the valve seat and the butterfly plate; it eliminates the wear at the upper and lower ends of the valve seat during frequent opening; it reduces the operating torque and lowers the requirements for the operating mechanism.

• Fireproof structure: The valve complies with the API607 standard and has passed the fire test. It has sealing ability in case of fire.

• Firm and reliable installation: A retaining ring is installed on the valve stem. Even if the valve stem breaks at the valve due to an unexpected situation, the upper part of the valve stem will not fall through the retaining ring.

• Convenient for loading and unloading: Just remove the insert to replace the valve seat without disassembling the butterfly plate and valve stem.

Performance advantages

Compared with other types of valves, the double-eccentric PTFE-sealed butterfly valve has obvious advantages:

• Structural and operational advantages: Simple structure, small size, light weight, low material consumption, small installation dimensions, small driving torque, easy and rapid operation.

• Functional feature advantages: It has good flow regulation function and excellent closing and sealing characteristics, with outstanding control performance. The flow curve changes in a geometric ratio, and the control range is wide. Even when used for flow control, the sealing remains reliable. The lug-type valve can be used as a terminal.

• Advantages in service life: The use of advanced processing methods and equipment in manufacturing ensures the machining accuracy of parts and the assembly accuracy, guaranteeing reliable sealing, minimal wear on the sealing surface, and a long service life of the whole machine.

Application fields

Double-eccentric PTFE-sealed butterfly valves are widely used. Type D343H and D343Y double-eccentric PTFE-sealed butterfly valves with PN6 – PN40 can be installed in systems such as petroleum, chemical industry, food, medicine, light textile, paper-making, hydropower, shipping, water supply and drainage, and smelting. They are used for regulation and cut-off on all pipelines and containers for corrosive and non-corrosive gases, liquids, semi-fluids and solid powders, and can be installed at any position.

Production-related

Some companies have a history of more than a decade in producing butterfly valve products. With the continuous progress of science and technology, they have absorbed and digested foreign advanced technologies and structural features, and developed double – eccentric sealed butterfly valves and triple – eccentric sealed butterfly valves. The sealing structures come in various forms such as soft sealing, multi – layer sealing, and hard sealing. These companies adopt advanced processes to ensure product quality. The triple – eccentric butterfly valves and double – eccentric butterfly valves series products they produce have been widely used in pipelines in multiple industries as valves for regulating flow and cutting off media.