Furnace braze deposition of hardface coating on wear surface

Patent metadata

Field	Value
Publication number	US-2016298780-A1
Application number	US-201615185188-A
Country	US
Kind code	A1
Filing date	Jun 17, 2016
Priority date	Nov 5, 2010
Publication date	Oct 13, 2016
Grant date	—

Abstract

A disclosed method of hard coating a wear surface of a valve of an aircraft air management system is performed by depositing a hardface alloy powder onto the wear surface, heating the wear surface and the hardface alloy powder to transform the hardface alloy powder into a molten liquid mass, and subsequently cooling the molten liquid hardface alloy mass to solidify the hardface alloy onto the wear surface. The disclosed process provides for localized application and subsequent bonding of the hardface alloy to discrete portions of the wear surface. The solidified hardface alloy coating may then be machined to obtain specific wear surface geometries.

First claim

What is claimed is:

1 . An air management system for an aircraft comprising:
a valve plate movable for controlling airflow through a passage; a valve shaft including an axial end supporting the valve plate within the passage; and a thrust plate for controlling axial movement of the valve shaft, the thrust plate including a thrust surface in contact with the axial end of the valve shaft, the thrust surface including a hardface alloy coating formed from a hardface alloy powder melted and solidified on the thrust surface.

2 . The air management system as recited in claim 1 , wherein the thrust surface is recessed and at least partially surrounded by walls.

3 . The air management system as recited in claim 2 , wherein the hardface alloy powder is disposed only on the thrust surface and not the walls.

5 . The air management system as recited in claim 2 , wherein the thrust surface is spaced apart from the walls.

6 . The air management system as recited in claim 2 , wherein the valve shaft includes a first diameter received within the thrust plate that is less than a second diameter outside of the thrust plate.

7 . The air management system as recited in claim 1 , wherein the hardface alloy is deposited onto the thrust surface as a powder and transformed into a mostly molten liquid mass on the thrust surface by elevating the thrust plate and the hardface alloy powder to a temperature sufficient to melt the hardface alloy powder and not melt the thrust plate.

8 . The air management system as recited in claim 1 , wherein the solidified hardface alloy is machined to provide a desired thickness on the thrust surface.

9 . The air management system as recited in claim 1 , including an actuator for controlling movement of the valve plate to control airflow through the passage.

10 . An airflow control valve comprising:
a valve plate movable for controlling airflow through a passage; a valve shaft including an axial end supporting the valve plate within the passage; and a thrust plate for controlling axial movement of the valve shaft, the thrust plate including a thrust surface in contact with the axial end of the valve shaft, the thrust surface including a hardface alloy coating formed from a hardface alloy powder melted and solidified on the thrust surface.

11 . The airflow control valve as recited in claim 10 , wherein the thrust surface is recessed and at least partially surrounded by walls.

12 . The airflow control valve as recited in claim 10 , wherein the thrust surface is spaced apart from the walls.

13 . The airflow control valve as recited in claim 10 , wherein the valve shaft includes a first diameter received within the thrust plate that is less than a second diameter outside of the thrust plate.

14 . The airflow control valve as recited in claim 10 , wherein the hardface alloy is deposited onto the thrust surface as a powder and transformed into a mostly molten liquid mass on the thrust surface by elevating the thrust plate and the hardface alloy powder to a temperature sufficient to melt the hardface alloy powder and not melt the thrust plate.

15 . The airflow control valve as recited in claim 10 , including an actuator for controlling movement of the valve plate to control airflow through the passage.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Rankin Kevin M
• Smith Blair A
• Boysen Timothy R
• Nardi Aaron T
• Brooky Keith J

Classifications

• F16K1/22

  with axis of rotation crossing the valve member, e.g. butterfly valves · CPC title

• B64D13/00

  Arrangements or adaptations of air-treatment apparatus for aircraft crew or passengers, or freight space · CPC title

• F16K25/005 Primary

  Particular materials for seats or closure elements · CPC title

• C23C24/106

  Coating with metal alloys or metal elements only · CPC title

• C23C4/18

  After-treatment · CPC title