# US 9,435,217 B2 · Swirl interruption seal teeth for seal assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,435,217 B2 - Document ID: US9435217B2 - Status: Granted - Kind: B2 - Application number: 14/875,726 - Filed: 2015-10-06 - Published: 2016-01-28 - Granted: 2016-09-06 - Earliest claimed: 2012-09-11 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Xiaoqing Zheng; Daniel Mark Brown; Jason Winfred Jewett; Fred Thomas Willett, Jr. - Web page: https://patentgrep.com/patent/US9435217B2 ## CPC - F01D 11/02: by non-contact sealings, e.g. of labyrinth type (for sealing space between rotor blade tips and stator F01D11/08) - F01D 11/08: for sealing space between rotor blade tips and stator (specially-shaped blade tips therefor F01D5/20) - F16J 15/4472: {with axial path} - F05D 2220/32: in gas turbines - F05D 2240/55: Seals - F05D 2250/191: perforated - F05D 2260/14: Preswirling - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A seal assembly for sealing between a rotating component and a stationary component in a turbomachine. The seal assembly includes a plurality of radially inwardly projecting, axially spaced teeth extending from the stationary component, wherein at least one of the plurality of teeth has at least one axially extending hole therethrough. Axial flow of an operating fluid through the holes acts as an air-curtain to interrupt swirl flow in a seal cavity, therefore reducing steam force that could act to destabilize rotordynamics. ## Claims ### Claim 1 A seal assembly for sealing between a rotating component and a stationary component in a turbomachine, the seal assembly comprising: a plurality of radially inwardly projecting, axially spaced teeth extending from the stationary component, wherein at least one tooth of the plurality of teeth has at least one axially extending hole therethrough, the axially extending hole extending through the at least one tooth from an upstream, high-pressure side to a downstream, low-pressure side of the at least one tooth and being distanced radially inwardly from a radially innermost surface of an arcuate packing ring, wherein the upstream, high-pressure side is in fluid communication with the downstream, low-pressure side via the at least one axially extending hole. ### Claim 2 (depends on 1) The seal assembly of claim 1, wherein the at least one tooth having the at least one axially extending hole therethrough comprises a first tooth on the upstream, high-pressure side. ### Claim 3 (depends on 1) The seal assembly of claim 1, wherein the at least one tooth having the at least one axially extending hole therethrough comprises a first tooth and a second tooth on the upstream, high-pressure side. ### Claim 4 (depends on 1) The seal assembly of claim 1, wherein the plurality of teeth comprise arcuate segments of teeth, and wherein the at least one axially extending hole comprises a plurality of circumferentially spaced holes along the arcuate portion of teeth. ### Claim 5 (depends on 1) The seal assembly of claim 1, wherein the at least one axially extending hole comprises a substantially cylindrical, tubular hole. ### Claim 6 (depends on 1) The seal assembly of claim 1, wherein the at least one axially extending hole comprises a slotted cut-out at a distal end of the at least one tooth. ### Claim 7 (depends on 1) The seal assembly of claim 1, wherein the at least one axially extending hole extends axially through the at least one tooth at an axial angle with respect to a centerline of the rotating component and at tangential angle with respect to a circumferential direction of the rotating component, wherein the axial angle is in the range of approximately 0 degrees to approximately 90 degrees and the tangential angle is in the range of approximately 0 degrees to approximately 60 degrees. ### Claim 8 (depends on 1) The seal assembly of claim 1, the seal assembly having a plurality of arcuate portions, each arcuate portion including an arcuate packing ring, wherein each arcuate packing ring is moveably mounted in a circumferential groove in the stationary component. ### Claim 9 (depends on 1) The seal assembly of claim 1, wherein the rotating element is a rotor. ### Claim 10 A turbomachine comprising: a rotating element; a stationary component substantially surrounding the rotating element; and a seal assembly coupled to the stationary component, the seal assembly including: a plurality of radially inwardly projecting, axially spaced teeth extending from the stationary component, wherein at least one tooth of the plurality of teeth has at least one axially extending hole therethrough, the axially extending hole extending through the at least one tooth from an upstream, high-pressure side to a downstream, low-pressure side of the at least one tooth and being distanced radially inwardly from a radially innermost surface of an arcuate packing ring, wherein the upstream, high-pressure side is in fluid communication with the downstream, low-pressure side via the at least one axially extending hole. ### Claim 11 (depends on 10) The turbomachine of claim 10, wherein the at least one tooth having the at least one axially extending hole therethrough comprises a first tooth on the upstream, high-pressure side. ### Claim 12 (depends on 10) The turbomachine of claim 10, wherein the at least one tooth having the at least one axially extending hole therethrough comprises a first tooth and a second tooth on the upstream, high-pressure side. ### Claim 13 (depends on 10) The turbomachine of claim 10, wherein the plurality of teeth comprise arcuate segments of teeth, and wherein the at least one axially extending hole comprises a plurality of circumferentially spaced holes along the arcuate portion of teeth. ### Claim 14 (depends on 10) The turbomachine of claim 10, wherein the at least one axially extending hole comprises substantially cylindrical, tubular hole. ### Claim 15 (depends on 10) The turbomachine of claim 10, wherein the at least one axially extending hole comprises a slotted cut-out at a distal end of the at least one tooth. ### Claim 16 (depends on 10) The turbomachine of claim 10, wherein the at least one axially extending hole extends axially through the at least one tooth at an axial angle with respect to a centerline of the rotating component and at tangential angle with respect to a circumferential direction of the rotating component, wherein the angle is in the range of approximately 0 degrees to approximately 90 degrees, and the tangential angle is in the range of approximately 0 degrees to approximately 60 degrees. ### Claim 17 (depends on 10) The turbomachine of claim 10, the seal assembly having a plurality of arcuate portions, each arcuate portion including an arcuate packing ring, wherein each arcuate packing ring is moveably mounted in a circumferential groove in the stationary component. ### Claim 18 (depends on 10) The turbomachine of claim 10, wherein the rotating element is a rotor. ### Claim 19 (depends on 10) The turbomachine of claim 10, wherein the seal assembly is an integral part of the stationary component. ### Claim 20 (depends on 10) The turbomachine of claim 10, wherein the seal assembly is rigidly attached to the stationary component.