Bonded seat valve
A valve seat includes a first end; a second end positioned opposite from the first end; and a body extending from the first end to the second end, the body defining an inner surface and an outer surface, the inner surface defining a main bore extending through the body from the first end to the second end, the main bore defining a main bore axis, the body defining a shaft bore extending from the inner surface to the outer surface, the shaft bore defining a shaft bore axis positioned perpendicular to the main bore axis, the shaft bore defining an inner shaft opening and an outer shaft opening, the body defining a concave seat bearing surface extending around the inner shaft opening.
1 . A valve seat comprising:
a body comprising a shaft bore extending from an inner seat surface to an outer seat surface and comprising an inner shaft opening defined at the inner seat surface;
a reinforced boss surrounding the shaft bore and protruding from the outer seat surface; and
a bearing pad extending radially inward from the inner seat surface relative to a main bore axis and defining a nonplanar seat bearing surface extending around the inner shaft opening,
wherein the nonplanar seat bearing surface is concave and defines a spherical zone which intersects a shaft bore surface of the shaft bore, the nonplanar seat bearing surface having a leak testing performance to contain 700 psi, and the shaft bore defines at least one annular rib located entirely within the reinforced boss, the reinforced boss having a height H and a side-wall thickness T such that 0.5≤H/T≤2.
2 . The valve seat of claim 1 , wherein the shaft bore defines an upper shaft bore, and the body further comprises a lower shaft bore extending from a lower inner shaft opening to a lower outer shaft opening.
3 . The valve seat of claim 2 , further comprising an upper boss within an upper boss recess and a lower boss within a lower boss recess.
4 . The valve seat of claim 1 , wherein the bearing pad comprises an interference fit.
5 . The valve seat of claim 4 , further comprising a shaft within the bearing pad, wherein the shaft comprises an interference fit within the bearing pad; and wherein the body exerts compressive forces on the bearing pad and the bearing pad exerts compressive forces on the shaft.
6 . A valve comprising the valve seat of claim 1 and a valve member defining an end engaging the concave seat bearing surface and an end surface defining a convex shape.
7 . The valve of claim 6 , further comprising a shaft extending through the shaft bore, the end receiving the shaft, the valve member being rotationally fixed to the shaft, wherein at least one annular rib is defined within the shaft bore.
8 . The valve of claim 6 , further comprising a valve body defining an inner body surface, the valve seat bonded to the inner body surface, the inner body surface defining a boss recess, the boss recess receiving the reinforced boss of the valve seat, the reinforced boss defining a sidewall thickness between an outer circumferential surface of the reinforced boss and a shaft bore surface of the shaft bore, the reinforced boss defining an outer shaft opening of the shaft bore, the reinforced boss defining a height between the outer shaft opening and a portion of the outer seat surface surrounding the reinforced boss, a ratio of the height divided by the sidewall thickness defining a value between 0.5 and 2.
9 . The valve of claim 6 , wherein the valve member is a disc, and the valve is a butterfly valve, wherein the outer seat surface defines a circumferential sealing rib extending circumferentially around the valve seat.
10 . The valve of claim 9 , further comprising a valve body defining an inner body surface bonded to the valve seat, the inner body surface defining a circumferential sealing groove.
11 . The valve of claim 9 , wherein the circumferential sealing rib defines an arcuate cross-sectional shape and when the valve is in a closed position:
the valve member contacts and seals with a portion of the inner seat surface positioned opposite from the circumferential sealing rib; and
the circumferential sealing rib compressed between a circumferential sealing groove and the valve member in a three-dimensional stress state.
12 . The valve of claim 11 , wherein the circumferential sealing rib is axially centered relative to a main bore axis.
13 . A method comprising:
providing a valve body comprising a main bore extending through the valve body from a first end to a second end;
forming a valve seat defining an inner seat surface defining a concave seat bearing surface extending around an inner shaft opening of the inner seat surface, an outer seat surface defining a cylindrical portion, the concave seat bearing surface having a leak testing performance to contain 700 psi, a reinforced boss surrounding a shaft bore and protruding from the outer seat surface, the reinforced boss having a height H and a side-wall thickness T such that 0.5≤H/T≤2, and at least one annular rib in the shaft bore located entirely within the reinforced boss; and
assembling a valve member defining an end engaging the concave seat bearing surface and an end surface defining a convex shape.
14 . The method of claim 13 , wherein forming the valve seat to define the nonplanar seat bearing surface further comprises forming a spherical zone in the concave seat bearing surface intersecting a shaft bore surface of the shaft bore.
15 . The method of claim 13 , wherein forming the outer seat surface comprises forming a circumferential sealing rib extending circumferentially around the valve seat.