# US 2020/0400033 A1 · Labyrinth seal abradable structure, notably for aircraft turbine

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2020/0400033 A1
- Document ID: US20200400033A1
- Status: Published application
- Kind: A1
- Application number: 16/765,026
- Filed: 2018-11-20
- Published: 2020-12-24
- Earliest claimed: 2017-11-21
- Assignees: Safran Aircraft Engines
- Applicants: Safran Aircraft Engines
- Inventors: Baptiste Marie Aubin Pierre JOUY; Mathieu Charles Jean VERDIERE
- Web page: https://patentgrep.com/patent/US20200400033A1

## CPC

- F01D 11/122: {with erodable or abradable material (blades having cutting or grinding tips F01D5/20)}
- F01D 11/02: by non-contact sealings, e.g. of labyrinth type (for sealing space between rotor blade tips and stator F01D11/08)
- F01D 11/127: {with a deformable or crushable structure, e.g. honeycomb}
- F16J 15/444: {with facing materials having honeycomb-like structure}
- F16J 15/445: {with means for adjusting the clearance}
- F16J 15/447: Labyrinth packings
- F05D 2250/283: honeycomb
- Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft
- 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
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

An abradable structure (36) is provided, with regions (44, 45, 46) with lower resistance to wearing produced by labyrinth seal lips (4, 5), at specific points in the axial direction of the turbomachine, where lip interference could cause the rotor to block up, such as after a temporary shutdown of the turbomachine. These regions may be produced by local weakening (38) or by the abradable material having a structure that is less dense. Application, for example, to turbomachine turbines.

## Claims

### Claim at position 1

1-13. (canceled)

### Claim 14

A labyrinth seal abradable structure (29, 36) disposed in a turbomachine around an axis (X) of the turbomachine, the labyrinth seal abradable structure comprising in an outer layer (55) provided with partitions (31, 32; 47; 64, 65) delimiting cells, at least three regions (33, 34, 35; 43, 44, 45, 46; 61, 62, 63) formed by annular bands of the abradable structure labyrinth seal which are juxtaposed to succeed one another in a direction of the axis (X) and have wear resistances of progressive values in the direction of the axis, wherein the cells are rectangular, the partitions in each of the regions are joined at junctions which connect only three cells together, and said partitions are oriented at an angle comprised between 30 and 60° relative to the direction of the axis (X).

### Claim 15 (depends on 14)

The labyrinth seal abradable structure according to claim 14, wherein, for each of the regions, the cells are in section of the polygons which have the same area.

### Claim 16 (depends on 15)

The labyrinth seal abradable structure according to claim 15, wherein the cells have, in cross-section, a different area for each region.

### Claim 17 (depends on 16)

The labyrinth seal abradable structure according to claim 16, wherein at least one cell of a region has a local weakened zone (38) so as to have a lower wear resistance than the other cells of the region.

### Claim 18 (depends on 14)

The labyrinth seal abradable structure according to claim 14, wherein some of the partitions are main rectilinear partitions which extend through several of the cells, and others of the partitions are subdivision partitions which extend only between two consecutive main partitions.

### Claim 19 (depends on 14)

The labyrinth seal abradable structure according to claim 14, wherein some of the partitions are main rectilinear partitions which extend through a plurality of the regions.

### Claim 20 (depends on 14)

The labyrinth seal abradable structure according to claim 14, wherein the partitions have a thickness comprised between 0.1 mm and 0.3 mm.

### Claim 21 (depends on 14)

The labyrinth seal abradable structure according to claim 14, wherein the labyrinth seal abradable structure is manufactured by an additive manufacturing technique and is formed in a single-piece.

### Claim 22

A turbomachine turbine, comprising a labyrinth seal abradable structure disposed around an axis (X) of the turbomachine, said structure comprising, in an outer layer (55) provided with partitions (31, 32; 47; 64, 65) delimiting cells, at least three regions (33, 34, 35; 43, 44, 45, 46; 61, 62, 63) formed by annular bands of the abradable structure labyrinth seal which are juxtaposed to succeed one another in a direction of the axis (X) and have wear resistances of progressive values in the direction of the axis, wherein the cells are rectangular, the partitions in each of the regions are joined at junctions which connect only three cells together, and said partitions are oriented at an angle comprised between 30 and 60° relative to the direction of the axis (X).

### Claim 23 (depends on 22)

The turbomachine turbine according to claim 22, wherein the labyrinth seal comprises wipers facing exclusively some of said annular bands of the labyrinth seal abradable structure, which are more resistant to wear, in a cruising condition of the turbomachine, others of said annular bands, but less resistant to wear, being located downstream of the previous ones.