Butterfly valve seal
AssigneeFisher Controls International LLC
InventorsBryan Leger, Wade Helfer
Life of this patent
Estimating the term…
Abstract
A valve assembly can include a valve body and a seal ring. The seal ring can be seated in a seal cavity of the valve body. The seal ring can include a base that extends in an axial direction within the seal cavity, a leg that extends from the base, and a foot that extends from the leg. When a disk of the valve assembly is in a closed valve position, a primary seal can be formed between the foot and the disk and a secondary seal is formed between the base and a first wall of the seal cavity. The seal ring can accommodate disk drift at least partly via elastic bending, and can provide disk tracking via lateral movement within the seal cavity.
Claims17
A valve assembly, comprising:
- a valve body;
- a valve passageway extending in an axial direction through the valve body;
- a disk arranged to selectively inhibit flow through the valve passageway of the valve body, the disk being movable between a valve open position and a valve closed position;
- a seal cavity formed at least partly in the valve body;
- and
- a seal ring including:
- a base extending continuously in the axial direction within the seal cavity to provide an upstream contact structure and a downstream contact structure, relative to flow through the valve passageway along the axial direction;
- a leg extending from the base transversely to the axial direction, from a location axially between the upstream and downstream contact structures;
- and
- a foot extending transversely from a distal end of the leg, at least partly in the axial direction,
- with the disk in the valve closed position and loaded with a first pressure from the upstream direction, a primary seal being formed between the foot of the seal ring and the disk and a secondary seal being formed between an axially oriented portion of the downstream contact structure and a downstream wall of the seal cavity.
A seal system for a butterfly valve that includes a disk and a seal ring cavity, the seal system comprising:
- a seal ring having a seal ring body, the seal ring body comprising:
- a base that extends continuously in an axial direction between an upstream end and a downstream end and is configured to be received within the seal ring cavity;
- a leg that extends inwardly from the base in a radial direction, to extend toward a disk of the butterfly valve from within the seal ring cavity, the leg being cantilevered relative to the base, in a cross-sectional plane that extends along the axial direction and the radial direction of the seal ring;
- and
- a foot extending from the leg in a downstream direction, opposite the base, to engage the disk of the butterfly valve to provide a primary seal when the disk is in a closed position,
- an axially oriented portion of the downstream end of the base being configured to provide a secondary seal at a downstream wall of the seal ring cavity;
- and
- the leg being flexibly supported relative to the base to permit rotation of the base upon axial loading of an upstream side of the leg, to provide a tertiary seal between the upstream end of the base and an upstream wall of the seal ring cavity.
A method of sealing a butterfly valve, the method comprising:
- rotating a disk of a butterfly valve toward a closed position so that the disk engages a foot of a seal ring, the seal ring having a base that extends continuously in an axial direction between an upstream end and a downstream end within a seal cavity of the butterfly valve, and a leg extending from the base, the foot extending from the leg opposite
- the base in a downstream direction relative to flow past the disk,
- applying a first upstream pressure to the disk, relative to a flow direction through the butterfly valve, so that:
- the leg deflects in the downstream direction to form a primary seal between the foot and the disk;
- and
- the base is loaded by the deflection of the leg to engage a downstream wall of the seal cavity with the downstream end to form a secondary seal between an axially oriented portion of the base and the seal cavity.
Dependencies are inferred from the claim text.