MANDREL, MANDREL REMOVAL AND MANDREL FABRICATION TO SUPPORT A MONOLITHIC NACELLE COMPOSITE PANEL

• US 20060225265A1
• Filed: 03/29/2005
• Published: 10/12/2006
• Est. Priority Date: 03/29/2005
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Fulbright, Leroy J., Craig, Barry B., Hackler, David W., Popp, Thomas D., Granger, Mitchel B., Sawyer, Christopher S., Burnett, John L., Kenney, Phillip E., Hoadley, Leo B., Wilson, Timothy C., Welch, John M.
• Granted Patent: US 7,571,527 B2
• Time in Patent Office: Days
• US Class Current: 29/448
• CPC Class Codes: B21D 53/92 other parts for aircraft
• CPC Class Codes: F02K 3/04 the plant including ducted fans, i.e. fans with high volume, low pressure outputs, for augmenting the jet thrust, e.g. of double-flow type
• CPC Class Codes: F05D 2230/20 essentially without removing material
• CPC Class Codes: F05D 2230/23 by permanently joining parts together
• CPC Class Codes: F05D 2230/64 using positioning or alignment devices for aligning or centring, e.g. pins
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y10T 29/37 Impeller making apparatus
• CPC Class Codes: Y10T 29/49629 Panel
• CPC Class Codes: Y10T 29/49815 Disassembling
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 29/49867 of skin on frame member
• CPC Class Codes: Y10T 29/49895 Associating parts by use of aligning means [e.g., use of a drift pin or a "fixture"]
• CPC Class Codes: Y10T 29/49902 by manipulating aligning means
• CPC Class Codes: Y10T 29/53961 with work-holder for assembly
• CPC Class Codes: Y10T 29/53983 Work-supported apparatus

Abstract

The present invention discloses a mandrel for fabricating a monolithic composite nacelle panel for use on an airplane. Also disclosed is the method of constructing the mandrel, the method of assembling the mandrel, and the method of disassembling the mandrel.

Claims

1. A mandrel for fabrication of a monolithic composite nacelle comprising:

a first fairing bar having a generally flat arch shape and at least two radially located apertures;

a second fairing bar having a generally flat arch shape and is positioned parallel to said first fairing bar;

a first outer section positioned between and attached to said first fairing bar and said second fairing bar, wherein said first outer section has an arch shaped cross section;

a second outer section positioned between and attached to said first fairing bar and said second fairing bar, wherein said second outer section has an arch shaped cross section;

a center section positioned between said first fairing bar and said second fairing bar and attached to said first outer section and said second outer section, wherein said center section has an arch shaped cross section;

a nozzle section attached to said first fairing bar and abutting said first outer section, said center section, and said second outer section; and

a ball roller assembly attached to said first fairing bar and including at least one drive mechanism and at least three rollers, wherein said drive mechanism and said ball rollers protrude through said apertures in said first fairing bar and contact said first outer section and said second outer section.

2. The mandrel of claim 1 further comprising a cavity section attached to said second fairing bar.

3. The mandrel of claim 1 further comprising a tilting plate attached to said first fairing bar.

4. The mandrel of claim 3 wherein said tilting plate includes a raised plate and a lower plate attached together by spacers, wherein said first fairing bar is attached to said raised plate.

5. The mandrel of claim 1 wherein said center section includes a first end, a second end, an outer wall, an inner wall, a first sidewall, and a second sidewall;

wherein said first end abuts said outer wall, said inner wall, said first sidewall and said second sidewall, said second end abuts said outer wall, said inner wall, said first sidewall and said second sidewall, said outer wall abuts said first sidewall and said second sidewall and said inner wall abuts said first sidewall and said second sidewall.

6. The mandrel of claim 5 wherein said center section second end has a larger cross sectional area than said center section first end, thus defining a tapered shape of the center section.

7. The mandrel of claim 1 wherein said first outer section includes a first end, a second end, an outer wall, an inner wall, a first sidewall, and a second sidewall;

wherein said first end abuts said outer wall, said inner wall, said first sidewall and said second sidewall, said second end abuts said outer wall, said inner wall, said first sidewall and said second sidewall, said outer wall abuts said first sidewall and said second sidewall and said inner wall abuts said first sidewall and said second sidewall.

8. The mandrel of claim 7 wherein said first outer section second end has a larger cross sectional area than said center section first end, thus defining a tapered shape of the first outer section.

9. The mandrel of claim 1 wherein said second outer section includes a first end, a second end, an outer wall, an inner wall, a first sidewall, and a second sidewall;

wherein said first end abuts said outer wall, said inner wall, said first sidewall and said second sidewall, said second end abuts said outer wall, said inner wall, said first sidewall and said second sidewall, said outer wall abuts said first sidewall and said second sidewall and said inner wall abuts said first sidewall and said second sidewall.

10. The mandrel of claim 9 wherein said second outer section second end has a larger cross sectional area than said center section first end, thus defining a tapered shape of the second outer section.

11. The mandrel of claim 1 wherein said nozzle section sits adjacent said inner wall of said first outer section, said inner wall of said center section, and said inner wall of said second outer section.

12. The mandrel of claim 11 wherein said first outer section inner wall includes a notched area for receipt of said nozzle section, said center section inner wall includes a notched area for receipt of said nozzle section, and said second outer section inner wall includes a notched area for receipt of said nozzle section.

13. The mandrel of claim 1 wherein said center section, said first outer section and said second outer section are held together by dovetail attachments.

14. The mandrel of claim 13 wherein said center section first sidewall includes a first male dovetail attachment, said center section second sidewall includes a second male dovetail attachment, said first outer section second sidewall includes a first female dovetail attachment and said second outer section first sidewall includes a second female dovetail attachment, wherein said first male dovetail attachment engages said first female dovetail attachment and said second male dovetail attachment engages said second female dovetail attachment.

15. The mandrel of claim 1 wherein said ball roller assembly includes rubber wheels that define an arc-shaped path, wherein said rubber wheels are in friction contact with said first outer section, said center section, and said second outer section.

16. The mandrel of claim 15 further comprising a roller ball track plate on said first end of said first outer section and roller ball track plate on said first end of said second outer section.

17. The mandrel of claim 16 wherein said roller ball track plate is generally arch-shaped and includes a groove along the length of said plate for receipt of said drive mechanism and said ball rollers.

18. The mandrel of claim 1 wherein said first outer section, said center section and said first outer section form vacuum tight seals with said first fairing bar and said second fairing bar when locked together.

19. The mandrel of claim 1 wherein said ball rollers are attached to a platform and said platform is attached to at least one hydraulic jack, that is also attached to said tilting plate, to position said ball rollers within aligned apertures of said tilting plate and said first fairing bar.

20. A method of constructing a mandrel for fabrication of a monolithic composite nacelle comprising the steps of:

(a) assembling a center section;

(b) assembling a first outer section;

(c) assembling a second outer section;

(d) adding a dovetail attachment to a first sidewall of said center section;

(e) adding a dovetail attachment to a second sidewall of said center section;

(f) adding a dovetail attachment to a second sidewall of said first outer section;

(g) adding a dovetail attachment to a first sidewall of said second outer section;

(h) aligning all dovetail attachments by laser tracking;

(i) attaching a sacrificial plate to a first fairing bar;

(j) attaching said first outer section to the sacrificial plate;

(k) attaching said second outer section to the sacrificial plate;

(l) attaching said center section to said first outer section and said second outer section by engaging said dovetail attachment on said center section first sidewall with said dovetail attachment on said first outer section second sidewall and by engaging said dovetail attachment on said center section second sidewall with said dovetail attachment on said second outer section first sidewall;

(m) attaching a nozzle section to the sacrificial plate adjacent to said first outer section, said center section, and said second outer section;

(n) machining the assembled first outer section, center section, second outer section, and nozzle section;

(o) disassembling the mandrel;

(p) removing the sacrificial plate; and

(q) reassembling the mandrel on the first fairing bar.

21. The method of claim 20 further comprising the step of attaching said first fairing bar to a tilting plate.

22. The method of claim 20 wherein assembling a center section includes the steps of:

forming an egg crate structure by welding together egg crate sections;

machining said egg crate structure to the proper contour;

stretch forming a metallic skin over said egg crate structure;

attaching said metallic skin to said egg crate by welding;

subjecting the center section to an anneal process; and

machining the exterior surface of the metallic skin to the proper contour.

23. The method of claim 22 wherein stretch forming a metallic skin over said egg crate structure includes the steps of:

stretch forming a metallic sheet over a stretch form block representing a center section inner wall that is defined by the egg crate structure;

welding said inner wall to said egg crate structure;

stretch forming a metallic sheet over a stretch form block representing a center section outer wall that is defined by the egg crate structure; and

welding said outer wall to said egg crate structure.

24. The method of claim 20 wherein assembling a first outer section includes the steps of:

forming an egg crate structure by welding together egg crate sections;

machining said egg crate structure to the proper contour;

stretch forming a metallic skin over said egg crate structure;

attaching said metallic skin to said egg crate by welding;

subjecting the first outer section to an anneal process; and

machining the exterior surface of the metallic skin to the proper contour.

25. The method of claim 24 wherein stretch forming a metallic skin over said egg crate structure includes the steps of:

stretch forming a metallic sheet over a stretch form block representing a first outer section inner wall that is defined by the egg crate structure;

welding said inner wall to said egg crate structure;

stretch forming a metallic sheet over a stretch form block representing a first outer section outer wall that is defined by the egg crate structure; and

welding said outer wall to said egg crate structure.

26. The method of claim 20 wherein assembling a second outer section includes the steps of:

forming an egg crate structure by welding together egg crate sections;

machining said egg crate structure to the proper contour;

stretch forming a metallic skin over said egg crate structure;

attaching said metallic skin to said egg crate by welding;

subjecting the second outer section to an anneal process; and

machining the exterior surface of the metallic skin to the proper contour.

27. The method of claim 26 wherein stretch forming a metallic skin over said egg crate structure includes the steps of:

stretch forming a metallic sheet over a stretch form block representing a second outer section inner wall that is defined by the egg crate structure;

welding said inner wall to said egg crate structure;

stretch forming a metallic sheet over a stretch form block representing a second outer section outer wall that is defined by the egg crate structure; and

welding said outer wall to said egg crate structure.

28. A method of assembling a mandrel for fabrication of a monolithic composite nacelle comprising the steps of:

(a) attaching a first fairing bar including an exposed ball roller assembly to a tilting plate;

(b) attaching a first outer section to said first fairing bar;

(c) attaching a second outer section to said first fairing bar;

(d) attaching a center section to said first outer section and said second outer section;

(e) attaching a nozzle section to said first fairing bar and positioned adjacent an inner wall of said first outer section, an inner wall of said center section, and an inner wall of said second outer section;

(f) attaching a second fairing bar to said first outer section, said center section, and said second outer section; and

(g) attaching a cavity section to said second fairing bar.

29. The method of claim 28 wherein said first fairing bar is bolted to said tilting plate.

30. The method of claim 28 wherein said ball roller assembly is bolted to said first fairing bar.

31. The method of claim 28 wherein said first outer section is bolted to said first fairing bar.

32. The method of claim 28 wherein said second outer section is bolted to said first fairing bar.

33. The method of claim 28 wherein said center section attaches to said first outer section and said second outer section by a locking dovetail attachment.

34. The method of claim 28 wherein said nozzle section is bolted to said first fairing bar.

35. A method of disassembling a first mandrel comprising the steps of:

(a) positioning the layed-up mandrel in an upright position resting on the tilting plate;

(b) removing the second fairing bar;

(c) removing the center section from between the first and second outer sections;

(d) rotating the first outer section about an arc-shaped path on the ball roller assembly toward where the center section had been positioned;

(e) removing the first outer section from within the first stage of the nacelle;

(f) rotating the second outer section on the ball roller assembly about an arc shaped path toward where the center section had been positioned;

(g) removing the second outer section from within the first stage of the nacelle;

(h) disassembling the first fairing bar from the tilting plate.

36. A method of assembling a second mandrel comprising the steps of:

(a) attaching a first fairing bar including an exposed ball roller assembly to the tilting plate;

(b) attaching the nozzle section to the first fairing bar;

(c) positioning the first outer section within the interior compartment of the first stage of the nacelle;

(d) rotating the first outer section on the ball roller assembly about an arc-shaped path into its proper position;

(e) attaching the first outer section to the first fairing bar;

(f) positioning the second outer section within the interior compartment of the first stage of the nacelle;

(g) rotating the second outer section on the ball roller assembly about an arc-shaped path into its proper position;

(h) attaching the second outer section to the first fairing bar;

(i) attaching the center section to the first outer section and the second outer section; and

(j) attaching the second fairing bar to the first outer section, the center section, and the second outer section.

37. A method of disassembling a second mandrel comprising the steps of:

(a) positioning the second mandrel in a vertical position resting on the tilting plate;

(b) removing the first fairing bar from the tilting plate;

(c) inverting the second mandrel so that the second fairing bar is resting on the tilting plate;

(d) removing the second fairing bar including the cavity section from the first outer section, center section and second outer section;

(e) inverting the second mandrel so that the first fairing bar is resting on the tilting plate

(f) removing the center section from between the first and second outer sections;

(g) rotating the first outer section about an arc shaped path toward where the center section had been positioned;

(h) removing the first outer section from within the nacelle;

(i) rotating the second outer section about an arc shaped path toward where the center section had been positioned;

(j) removing the second outer section from within the nacelle; and

(k) removing the nacelle from the first fairing bar.