Title:
BALL VALVE
Document Type and Number:
Japanese Patent JPS58137673
Kind Code:
A
Abstract:
PURPOSE:To prevent fluid from being leaked to the outside of a valve by a method wherein a ring-shaped seat ring is provided between the inner surface of a valve box and the outer surface of the ball, notched grooves are formed on the inner peripheral surface of the seat ring, a tapered surface is formed at the back side of the ring and a gap is provided between the outer end of the seat ring and the inner surface of the stepped part of the valve box. CONSTITUTION:Notched grooves 9 are provided on the inner peripheral surface of a ring-shaped seat ring 4, consisting of an elastic material such as fluorine plastics or the like, at the side of a cavity 8 while the tapered surface 4c, having a slope equal to or smaller than the slope of the inner peripheral surface, is formed at the back side thereof. The seat ring 4 causes a compressive deformation, corresponding to an interference 12 because it is pinched by the valve box 1 and the ball 3 while it keeps a clearance 10 between the inner surface 11 of the stepped part of the valve box. When the liquid pressure in the cavity 8 is increased, pressure P1-P4 are applied to the ring, however, the pressures P2, P4 are cancelled each other and the component of the pressures P1, P3 is applied thereto, therefore, the seat ring 4 moves under keeping the interference 12.
Inventors:
FUKUDA SEIJI
Application Number:
JP1745382A
Publication Date:
August 16, 1983
Filing Date:
February 08, 1982
Export Citation:
Assignee:
HITACHI METALS LTD
International Classes:
F16K5/06; (IPC1-7): F16K5/06
Attorney, Agent or Firm:
Takashi Honma