Interchangeable valve seat assembly

Claim 2

An interchangeable valve seat assembly for use in a valve body, said valve seat assembly comprising: a casing having a walled cavity therein; a retaining base integral with said casing and defining an aperture in fluid communication with said cavity; an interchangeable and substantially annularly shaped valve seat removably located within the cavity and in contacting and fluid-sealing relationship with said retaining base; a first stepped flange integral with the retaining base, said first stepped flange being located adjacent to said aperture and spaced from said cavity to define an annular receiving space; a second stepped flange integral with said seat, said second stepped flange being formed at the outer periphery of said seat and located in said annular receiving space in engagement with said first stepped flange; and retaining means for holding said seat in a position where said first stepped flange is in contact and fluid-sealing relationship with said second stepped flange.

Claim 3

A valve seat assembly as in claim 1 wherein said retaining means comprises an outer threaded wall on said valve seat, the cavity is substantially cylindrical in shape and the wall of said cavity is threaded to removably receive and engage the outer threaded wall of the seat.

Claim 4

A valve seat assembly as in claim 1, wherein: said first stepped flange on said retaining base projects perpendicularly upward from said retaining base; and said second stepped flange located adjacent to the outer periphery of said valve seat projects perpendicularly downward from its lower surface for engagement with said first flange formed on said retaining base.

Claim 5

A valve seat assembly as in claim 1 wherein the cavity is substantially cylindrical in shape and the wall of the cavity is threaded, and said retaining means comprises a threaded nut engaging the threaded cavity wall and contacting the seat to press the seat into fluid-sealing relationship with the retaining base.

Claim 6

A valve seat assembly as in claim 4 wherein the seat includes a ledge formed at its periphery above said second stepped flange, said nut engaging said ledge and forcing the second stepped flange of the seat into said annular receiving space and into fluid-sealing relationship with the retaining base and the first stepped flange of the base.

Claim 7

A valve seat assembly as in claim 1 wherein the wall of the cavity has a groove therein and said retaining means comprises a retention ring positioned within the groove for retaining the seat in position in fluid-sealing relationship with the retaining base.

Claim 8

A valve seat assembly as in claim 6 wherein the retention ring has an inner diameter smaller than the outer diameter of the annularly shaped seat.

Claim 9

An interchangeable valve seat assembly for use in a valve body, said valve seat assembly comprising: a casing having a walled cavity therein, the wall of said cavity having a groove; a retaining base integral with said casing and defining an aperture in fluid communication with said cavity; an interchangeable and substantially annularly shaped valve seat removably located within the cavity and in contacting and fluid-sealing relationship with said retaining base; a stepped flange integral with the retaining base; and a reTention ring positioned within the groove for retaining the seat in position in fluid-sealing relationship with the retaining base, said retention ring having an inner diameter smaller than the outer diameter of the annularly shaped seat; and said casing including notches in communicating relationship with said groove whereby a tool or other device can be inserted into one or more of the notches to remove the retention ring from the groove and to permit removal of the seat.

Claim 10

An interchangeable valve seat assembly for use in a valve body, said valve seat assembly comprising: a casing having a walled cavity therein, the wall of said cavity having a groove; a retaining base integral with said casing and defining an aperture in fluid communication with said cavity; an interchangeable and substantially annularly shaped valve seat removably located within the cavity and in contacting and fluid-sealing relationship with said retaining base; a stepped flange integral with the retaining base; and a reTention ring positioned within the groove for retaining the seat in position in fluid-sealing relationship with the retaining base, said retention ring having an inner diameter smaller than the outer diameter of the annularly shaped seat; and said casing including notches in communicating relationship with said groove whereby a tool or other device can be inserted into one or more of the notches to remove the retention ring from the groove and to permit removal of the seat.