Masking fixture

Patent metadata

Field	Value
Publication number	US-10913138-B2
Application number	US-201815982746-A
Country	US
Kind code	B2
Filing date	May 17, 2018
Priority date	May 17, 2017
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A masking fixture includes a flexible cover and a rigid cover. The flexible cover is received within a cavity of the rigid cover. An air connector provides for a purge flow supply to be connected to the masking fixture via a port in fluid communication with an enclosure of the flexible cover. A method of treating a workpiece includes directing a pressurized fluid jet comprising an abrasive media entrained therein against an exterior surface of the workpiece and directing a purge flow through the workpiece while directing the pressurized fluid jet against the exterior surface.

First claim

What is claimed is:

1. A method of treating a workpiece, the method comprising:
directing a pressurized fluid jet comprising an abrasive media entrained in the pressurized fluid jet against an exterior surface of the workpiece;
directing a purge flow through the workpiece while directing the pressurized fluid jet against the exterior surface; and
positioning a first masking fixture on a first end of the workpiece and positioning a second masking fixture on a second end of the workpiece prior to directing the pressurized fluid jet, wherein directing the purge flow comprises directing the purge flow through a first port extending through a first base wall of the first masking fixture into an interior cavity of the workpiece and through a second port extending through a second base wall of the second masking fixture into the interior cavity of the workpiece.

2. The method of claim 1 , wherein directing the purge flow comprises directing the purge flow through an interior cavity of the workpiece.

3. The method of claim 2 , wherein directing the purge flow further comprises directing the purge flow from the interior cavity of the workpiece to an ambient environment around the workpiece through a plurality of holes in the exterior surface of the workpiece.

4. The method of claim 1 , wherein positioning the first masking fixture comprises forming a purge flow cavity between a flexible sealing cover of the first masking fixture and the first end of the workpiece and positioning the second masking fixture comprises forming a second purge flow cavity between a sealing cover of the second masking fixture and the second end of the workpiece.

5. The method of claim 1 , wherein positioning the first masking fixture further comprises sealingly engaging a first flexible sealing cover of the first masking fixture with a first end of the workpiece and wherein positioning the second masking fixture further comprises sealingly engaging a second flexible sealing cover of the second masking fixture with a second end of the workpiece.

6. The method of claim 5 , wherein positioning the first masking fixture further comprises sealingly engaging the flexible sealing cover of the first masking fixture with a rigid cover of the first masking fixture and wherein positioning the second masking fixture further comprises sealingly engaging the flexible sealing cover of the second masking fixture with a rigid cover of the second masking fixture.

7. The method of claim 1 , wherein directing the purge flow further comprises directing the purge flow from the interior cavity of the workpiece to an ambient environment around the workpiece through a plurality of holes in the exterior surface of the workpiece.

8. The method of claim 1 , further comprising fastening together the first masking fixture and the second masking fixture about the workpiece prior to directing the pressurized fluid jet.

9. The method of claim 1 , wherein a pressure of the purge flow is greater than a pressure of the pressurized jet.

10. The method of claim 9 , wherein the pressure of the purge flow is at least 3 bar greater than the pressure of the pressurized jet.

11. A masking fixture for protecting a workpiece during treatment of the workpiece, the masking fixture comprising:
a flexible cover, the flexible cover comprising:
a peripheral rim;
a base wall parallel to and spaced from the peripheral rim;
a plurality of sidewalls extending between the peripheral rim and the base wall, the plurality of sidewalls generally orthogonal to the peripheral rim and the base wall;
an enclosure defined by the base wall and the plurality of sidewalls;
an internal rim extending parallel to the peripheral rim and the base wall, the internal rim positioned within the enclosure between the base wall and the peripheral rim;
a projection extending from the base wall towards the peripheral rim, the projection generally orthogonal to the base wall;
a port formed extending through the base wall for connecting a purge air supply, the port in fluid communication with the enclosure; and
a pressurized purge flow cavity within the enclosure, the pressurized purge flow cavity defined by the base wall and selected sidewalls of the plurality of sidewalls.

12. The masking fixture of claim 11 , further comprising a rigid cover, the rigid cover comprising a base wall and a plurality of side walls extending generally orthogonal to the base wall of the rigid cover, an inner surface of the base wall of the rigid cover and inner surfaces of the plurality of sidewalls of the rigid cover defining a cavity of the rigid cover, the flexible cover received within the cavity of the rigid cover.

13. The masking fixture of claim 12 , further comprising a chamfer defined in an inner corner of each sidewall of the plurality of sidewalls of the rigid cover.

14. The masking fixture of claim 12 , wherein the flexible cover further comprises an outer surface configured to form an interference fit with a corresponding portion of the inner surfaces of the plurality of sidewalls of the rigid cover.

15. The masking fixture of claim 14 , wherein the portion of the inner surfaces of the plurality of sidewalls of the rigid cover comprises a chamfer defined in an inner corner of each sidewall of the plurality of sidewalls of the rigid cover.

16. The masking fixture of claim 11 , further comprising a plurality of fasteners extending from the rigid cover for securing the masking fixture to a complementary masking fixture about a workpiece.

Assignees

• Gen Electric

Inventors

• Strzyzewski Mariusz
• Kowalczyk Michal
• Skiba Pawel Stanislaw
• Bekey Mihaly Laszlo

Classifications

• B05B12/20

  Masking elements, i.e. elements defining uncoated areas on an object to be coated · CPC title

• B24B31/12

  Accessories; Protective equipment or safety devices; Installations for exhaustion of dust or for sound absorption specially adapted for machines covered by group B24B31/00 {(in general B24B55/00)} · CPC title

• B24C9/003

  Removing abrasive powder out of the blasting machine · CPC title

• F01D25/285 Primary

  Temporary support structures, e.g. for testing, assembling, installing, repairing; Assembly methods using such structures · CPC title

• B23P6/002

  Repairing turbine components, e.g. moving or stationary blades, rotors, (B23P6/045 takes precedence) · CPC title