Patent ID: 7357372
Filing Date: 2008-04-15
Classification: F16K

Abstract:
1. A seat ring assembly for a butterfly valve comprising: a tubular body portion defining a valve body axis along a tubular direction of the tubular body portion, the tubular body portion having two side flange surfaces disposed at opposing body portion ends, said tubular body portion having at least one stem through hole extending in a radial direction of said tubular body portion and defining a stem axis; an outer circumference portion of said tubular body portion being formed having an elliptic shape taken in a plane perpendicular to said valve body axis with a stem axial direction as a longitudial axis of said elliptic shape; an inner circumference portion of said body portion formed having a circular shape taken in the plane perpendicular to said valve body axis and a constant radius; an annular protrusion protruding radially outwardly from an axial center of said outer circumference portion of said body portion; a valve plug body defining a circular through valve body opening, said tubular body portion being installed in said circular through valve body opening in a compressed state such that said outer circumference portion is compressed at areas intersected by said longitudinal axis of said elliptic shape such that said inner circumference portion is deformed from said circular shape to an elliptic shape; and wherein a ratio of a first thickness dimension of the body portion from the inner circumference portion to the outer circumference portion in the stem axial direction to the thickness dimension in the direction perpendicular to the stem axis from the inner circumference portion to the outer circumference portion is 1.01:1 to 2:1.