BUTTERFLY VALVE BLADE

摘要

A butterfly valve blade (1) in the form of a solid dish (2) having spherical outer and inner axial surfaces (6, 7) steadily increasing in thickness (t) from the center (6) to the rim (7); the shape and proportions of the blade being designed such that the neutral axis of bending of the blade normal to the pivotal axis (A-A) of the blade is substantially coincident with the centre line (CL) through the blade and normal to the pivotal axis (A-A), the blade providing equal isolation for both directions of fluid flow through the valve.