Faden High Quality Water Plant Special Horizontal Double Eccentric Butterfly Valve with Large Diameter

Faden High Quality Water Plant Special Horizontal Double Eccentric Butterfly Valve with Large DiameterFaden High Quality Water Plant Special Horizontal Double Eccentric Butterfly Valve with Large Diameter

Double eccentric butterfly valve, also known as high-performance butterfly valve, is a further improvement on the basis of single eccentric butterfly valve. The so-called double eccentric refers to its valve stem axis deviating from both the center of the butterfly plate and the center of the body. The double eccentric effect enables the butterfly plate to quickly detach from the valve seat after the valve is opened, greatly eliminating excessive compression and scratching between the butterfly plate and the valve seat, reducing the opening distance, lowering wear, and improving the service life of the valve seat; Compared with the centerline butterfly valve, the double eccentric butterfly valve is more resistant to high pressure, has good stability, and has a longer service life; Compared with other valves, the larger the diameter, the lighter the material and the lower the cost.Mainly suitable for drainage systems in water plants, power plants, steel mills, chemical engineering, environmental facility construction, etc., especially suitable for use as regulating and intercepting equipment on pipelines larger than DN200. Due to the significant reduction in the scraping force between the butterfly plate and the valve seat during use, the double eccentric butterfly valve can also use a metal valve seat, thereby improving its application in high-temperature fields.

Structural features of double eccentric butterfly valve: The center of rotation of the valve plate (i.e. the center of the valve shaft) forms a dimension α offset with the sealing section of the valve plate, and forms a dimension b offset with the centerline of the valve body.

Sealing principle of double eccentric butterfly valve: Based on the single eccentric sealing butterfly valve, the center of rotation of the valve plate (i.e. the center of the valve shaft) is offset by a dimension b with the centerline of the valve body. When the double eccentric sealing butterfly valve is in the open state, the sealing surface of the valve plate will detach from the sealing surface of the valve seat, and a larger gap y will be formed between the sealing surface of the valve plate and the sealing surface of the valve seat than the X gap in the single eccentric sealing butterfly valve, thereby reducing mechanical wear and abrasion between the sealing surfaces of the butterfly valve sealing pair during valve opening and closing.

In a typical design, when the valve plate rotates from 0 ° to 8 ° to 12 °, the sealing surface of the valve plate can detach from the sealing surface of the valve seat, resulting in relative mechanical wear and shorter extrusion angle stroke between the sealing surfaces of the valve plate and the valve seat during the opening and closing process of the butterfly valve. This reduces mechanical wear and extrusion deformation, and improves the sealing performance of the butterfly valve.

Characteristics of Double Eccentric Butterfly Valve

① The structure is more complex than that of a single eccentric sealed butterfly valve, and the cost is slightly higher;

② The sealing performance is better than that of a single eccentric sealing butterfly valve;

③ The service life is longer than that of a single eccentric sealed butterfly valve, and the operating pressure is also higher.