Title:
METAL SEAT BUTTERFLY VALVE
Document Type and Number:
Japanese Patent JP3003762
Kind Code:
B2
Abstract:
PURPOSE: To uniformly disperse the contact pressure of the seat faces of a valve body side metal seat and a valve casing side metal seat for providing an excellent water cut-off performance by forming the seat face of the valve body side metal seat into a projected circular arc face having a specific radius of curvature and the seat face of the valve casing side metal seat into a recessed circular arc face having a specific radius of curvature.
CONSTITUTION: In a metal seat butterfly valve a disk-like valve body 3 is turnably supported in a cylindrical valve casing 1 through a valve shaft 2, and ring-like metal seats 4 and 5 are firmly attached by casting in a body to the peripheral surfaces of the valve body 3 and the valve casing 1 opposing to each other by casting respectively. In such a valve, the seat surface 4a of a valve body 3 side metal seat 4 is formed into a projected circular arc face having a center Q1 deviated by a fixed distance D1 orthogonal to the axis X of the valve casing 1 and having a radius R1 of curvature that is smaller than the turning radius Ra of the valve body 3. On the other hand, the seat surface of a valve casing 1 side metal seat 5 is formed into a recessed circular arc face having a center deviated a fixed distance from a virtual center line Y and having a radius R1 or larger of curvature.
Inventors:
Yoshifumi Nakakubo
Application Number:
JP15774694A
Publication Date:
January 31, 2000
Filing Date:
July 11, 1994
Export Citation:
Assignee:
Kubota Corporation
International Classes:
F16K1/226; F16K1/34; (IPC1-7): F16K1/226; F16K1/34
Attorney, Agent or Firm:
Yoshihiro Morimoto