Non-lubricated system with abradable sealing element, corresponding sealing element and method for assembling the system

Patent metadata

Field	Value
Publication number	US-12209586-B2
Application number	US-202017419863-A
Country	US
Kind code	B2
Filing date	Jan 27, 2020
Priority date	Jan 29, 2019
Publication date	Jan 28, 2025
Grant date	Jan 28, 2025

Abstract

A non-lubricated system for pumping a gas, includes a stationary stator with a housing that includes a rotor cavity and at least one rotatable rotor element incorporated within the rotor cavity. The stator includes at least one self-supporting sealing element, incorporated within the rotor cavity between an end face of at least one of the rotor elements and an interior wall of the housing to form a seal along the corresponding end face. At least one self-supporting sealing element is provided with an abradable coating on at least one side facing the rotor.

First claim

The invention claimed is:

1. A non-lubricated system for pumping a gas, comprising a stationary stator with a housing comprising a rotor cavity and at least one rotatable rotor element incorporated within the rotor cavity, where the stator further comprises at least one self-supporting sealing element, incorporated in the rotor cavity between an end face of at least one of the rotor elements and an interior wall of the housing, to form a seal along the end face, wherein an abradable coating is on at least one side facing the corresponding rotor element of the at least one self-supporting sealing element, wherein at least the abarable coating consists of a carbon matrix.

2. The non-lubricated system in accordance with claim 1 , wherein the at least one self-supporting sealing element has a thickness of at least 1.0 mm.

3. The non-lubricated system in accordance with claim 1 , wherein the abradable coating has a thickness of at least 100 μm.

4. The non-lubricated system in accordance with claim 1 , wherein the at least one self-supporting sealing element is mainly plate-like.

5. The non-lubricated system in accordance with claim 1 , wherein the at least one self-supporting sealing element consists of a layered structure.

6. The non-lubricated system in accordance with claim 1 , wherein the carbon matrix has a degree of graphitization P1 of more than 60%, more than 80% or more than 95%.

7. The non-lubricated system in accordance with claim 1 , wherein the abradable coating has a hardness HR 5/100 between 100 and 120.

8. The non-lubricated system in accordance with claim 1 , wherein at least one end face of at least one of the rotor elements has a contact surface with a roughness Ra>1.0 μm.

9. A non-lubricated system for pumping a gas, comprising a stationary stator with a housing comprising a rotor cavity and at least one rotatable rotor element incorporated within the rotor cavity, where the stator further comprises at least one self-supporting sealing element, incorporated in the rotor cavity between an end face of at least one of the rotor elements and an interior wall of the housing, to form a seal along the end face, wherein an abradable coating is on at least one side facing the corresponding rotor element of the at least one self-supporting sealing element, wherein at least one end face of at least one of the rotor elements is notched around a rotor shaft of the rotor element and wherein the abradable coating of the at least one self-supporting sealing element present there comprises a ring extending into the notch.

10. The non-lubricated system in accordance with claim 1 , wherein the at least one self-supporting sealing element comprises one or more openings for the supply and/or exhaust of the gas.

11. The non-lubricated system in accordance with claim 1 , wherein the system is a compressor, expander or vacuum pump.

12. A self-supporting sealing element according to claim 1 , configured for use in a non-lubricated system for pumping the gas.

13. A method for assembling a non-lubricated system in accordance with claim 1 , comprising the following steps:
attaching the at least one self-supporting sealing element to the interior wall of the housing of the stator, wherein the respective abradable coating is turned away from the respective interior wall;
incorporating rotatably the at least one rotor element in the rotor cavity bounded by the housing; and
running-in the system to partially wear down the abradable coating.

14. The method in accordance with claim 13 , further comprising a step of roughening at least one end face of at least one rotor element.

15. The method in accordance with claim 13 , wherein the attaching comprises the application of a sealant and/or adhesive between the at least one self-supporting sealing element and the respective interior wall of the stator housing.

16. The method in accordance with claim 13 , wherein the end face of the at least one of the rotor elements is notched around a rotor shaft of the rotor element and wherein during the running-in, as a result of the run-in, a ring is formed on the abradable coating of the self-supporting sealing element present there, which extends into the notch.

17. The non-lubricated system in accordance with claim 2 , wherein the at least one self-supporting sealing element has a thickness of at least 1.5 mm.

18. The non-lubricated system in accordance with claim 17 , wherein the at least one self-supporting sealing element has a thickness of at least 2.0 mm.

19. The non-lubricated system in accordance with claim 3 , wherein the at least one self-supporting sealing element has a thickness of at least 200 μm.

20. The non-lubricated system in accordance with claim 19 , wherein the at least one self-supporting sealing element has a thickness of at least 300 μm.

21. The non-lubricated system in accordance with claim 1 , wherein the entire at least one self-supporting sealing element consists of a carbon matrix.

22. The non-lubricated system in accordance with claim 21 , wherein the carbon matrix has a degree of graphitization P1 of more than 60%, more than 80% or more than 95%.

23. The non-lubricated system in accordance with claim 8 , wherein at least one end face of at least one of the rotor elements has a contact surface with a roughness Ra>2.5 μm.

Assignees

• Atlas Copco Airpower Nv

Inventors

• Marien Karen Anna Leon
• Peeters Guido Jozef Christian

Classifications

• H02K16/02

  Machines with one stator and two {or more} rotors · CPC title

• H02K5/10

  with arrangements for protection from ingress, e.g. water or fingers · CPC title

• F04C18/126

  with radially from the rotor body extending elements, not necessarily co-operating with corresponding recesses in the other rotor, e.g. lobes, Roots type · CPC title

• F04C2270/16

  Wear · CPC title

• F04C2240/801

  Wear plates · CPC title