Double eccentric butterfly valve

Shape and connection size

Main parts materials

Eccentric hemispherical valve structure diagram

Double eccentric butterfly valve is a new generation of products carefully designed by Grand Valve Group, with the characteristics of quick opening, convenient and small installation space, which can be widely used in various pipelines of urban water supply and drainage, construction, fire protection, metallurgy, hydropower and other systems, mainly as interception, connection and regulation of flow.

Technical specifications

Principle

Worm operation, rotating the worm handwheel rotates the valve stem by 90°, driving the butterfly plate to rotate 90°, so as to realize opening or closing. Because the product is a double eccentric structure, it can produce a cam effect during the opening and closing process, which reduces the valve opening and closing torque, reduces the wear between the valve seat and the butterfly plate, and prolongs the service life of the valve.

Flow resistance curve diagram

Note: 1. This curve is universal data, and the accurate value is subject to the actual product that meets the user’s requirements, and the on-site debugging results shall prevail;
2. This diagram is specially provided for “equipment procurement of PCCP pipeline section of Yinchuo Jiliao Project”.

Structural features:

◆ The double sealing ring structure completely solves the problem of shaft hole leakage. Thrust bearings are added to the bottom of the large diameter to reduce the valve torque. (Figure A)

◆ Adopt double eccentric butterfly plate structure: the rotation centerline of the butterfly plate (valve shaft) deviates from the pipeline centerline upwards (eccentricity E1) and deviates from the centerline of the sealing surface to the left (eccentricity E2). When the valve is opened and closed, the butterfly plate sealing surface can quickly detach or contact the sealing surface of the valve seat, so the friction stroke is short, the friction torque is small, the opening and closing are easy, and the sealing surface has a long service life. (Figure B)

◆ The sealing pressure ring can be adjusted to effectively solve the problem of valve leakage, and the clearance can be adjusted during assembly, and the sealing ring can be adjusted to achieve zero leakage by adjusting the interference of the sealing ring, and the sealing ring is thickened and widened, extending the life of the rubber; The positioning screw adjusts the rubber clearance to prevent the pressure ring from loosening. (Figure C)

◆ Using advanced finite element analysis software such as flow field simulation and stress measurement, the structure, size, material, and performance of the product all meet or exceed the national standard, and have first-class mechanical properties. (Figure D)

◆ Sealing surface overlay stainless steel, corrosion resistance and long service life.

◆ The surface is sprayed with epoxy resin powder, which is anti-corrosion, durable, and pollution-free to the environment.