Triple Eccentric Butterfly Valve is a common control valve with the advantages of small opening torque, good sealing performance and long service life. Its structure is unique, consisting of three eccentric parts, so it is called “three eccentric butterfly valve”.
Triple eccentric butterfly valves are suitable for many places, it has a large choice of materials, high and low temperatures and a variety of acids, alkalis and other corrosive media can also correspond to freely. Especially in large calibre, with its zero leakage advantage, it is constantly replacing the bulky gate and ball valves in shut-off valves; similarly, with its advantage of regulating function, it is also constantly replacing the bulky globe valves in regulating valves. At present, three eccentric butterfly valves have been widely used in various important pipelines, including oil and gas extraction, offshore platforms, petroleum refining, petrochemicals, inorganic chemicals, energy generation, and other major industrial fields, such as process control.
The term eccentric butterfly valve is based on the sealing structure of the butterfly valve. Butterfly valves can be divided into concentric butterfly valves, single eccentric butterfly valves, double eccentric butterfly valves and triple eccentric butterfly valves according to the sealing structure characteristics.
Today TWT,China would like to focus on the eccentricity of butterfly valves and talk to buyers in detail about the development process of eccentricity.
Three eccentricities of butterfly valve
First eccentricity refers to the eccentricity at the connection between the butterfly plate and the valve stem. During the opening and closing process, the butterfly plate will rotate along the axis of the valve stem. When the connection between the butterfly plate and the valve stem deviates from the center position, an eccentric torque will be generated, causing the valve to open or close. The size of this eccentric moment depends on the eccentric angle at the connection between the butterfly plate and the valve stem and the diameter of the valve.
The second eccentricity refers to the eccentricity between the butterfly plate and the valve seat. During the opening and closing process, the butterfly plate will rotate around the valve seat. When the eccentric angle between the butterfly plate and the valve seat is large, a large eccentric torque will be generated, causing the valve to open or close. The size of this eccentric moment also depends on the eccentric angle between the butterfly plate and the valve seat and the diameter of the valve.
Triple eccentricity refers to the eccentricity between the butterfly plate and the axis of the pipe. During the opening and closing process, the butterfly plate will rotate around the axis of the pipeline. When the eccentric angle between the butterfly plate and the axis of the pipeline is large, a large eccentric torque will be generated, causing the valve to open or close. The size of this eccentric moment also depends on the eccentric angle between the butterfly plate and the pipeline axis and the diameter of the valve.
The emergence of offset butterfly valve plays a vital role in the opening and closing of the valve. At the same time, this is also one of the important reasons why eccentric butterfly valves can be widely used in various pipeline systems.
Specification of TWT offset butterfly valves
PN represents the pressure of pipes, pipe fittings, valves and other shell equipment. Just like the specifications of pipes, valves, etc. are represented by DN, the pressure of pipes, valves, etc. is represented by pn.PN16 Offset Butterfly Valves By TWT means the nominal pressure is 1.6mpa.
Valve plate material of PN16 Offset Butterfly Valves By TWT is QT450/CF8 stainless steel, 16 pressure, diameter DN50, suitable for temperatures ≤120°C, adaptable to some corrosive environments with strong acids and alkalis, and the needs of many special fields such as petroleum, chemical industry, food, etc., in conventional butterfly valves The inside of the valve and the valve plate are lined with polytetrafluoroethylene to isolate the medium from the valve body and achieve anti-corrosion effect.