Method of manufacturing curved composite structural elements

• US 8,632,653 B2
• Filed: 05/03/2005
• Issued: 01/21/2014
• Est. Priority Date: 05/03/2005
• Status: Expired due to Fees

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Brown, Todd A., Friddell, Stephen Douglas, Harris, Christopher G., Modin, Andrew E.
• Primary Examiner(s): Khare, Atul P.
• Application Number:
  US11/119,756
• Publication Number:
  US 20060249868A1
• Time in Patent Office: 3,185 Days
• Field of Search: 264/137, 264/258, 264/257, 264/235, 264/236, 156/166, 156/173, 156/196, 156/245, 156/285, 156/264, 156/304.1
• US Class Current: 156/304.1
• CPC Class Codes: B29C 43/12 using bags surrounding the moulding material or using membranes contacting the moulding material
• CPC Class Codes: B29C 70/342 using isostatic pressure
• CPC Class Codes: B29C 70/382 Automated fiber placement [AFP]
• CPC Class Codes: B29C 70/386 Automated tape laying [ATL]
• CPC Class Codes: B29C 70/48 and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] , e.g. by vacuum
• CPC Class Codes: B29C 70/545 Perforating, cutting or machining during or after moulding
• CPC Class Codes: B29K 2063/00 Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2067/00 Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2307/00 Use of elements other than metals as reinforcement
• CPC Class Codes: B29K 2309/10 Mica
• CPC Class Codes: B29L 2031/003 having a profiled transverse cross-section
• CPC Class Codes: B29L 2031/3082 Fuselages
• CPC Class Codes: B32B 38/0004 Cutting, tearing or severing, e.g. bursting; Cutter details cutting in general B26D; laminating combined with punching or perforating B32B38/04; removing all or part of the layers B32B38/10; cutting in combination with laying up and registration B32B38/185 takes precedence
• CPC Class Codes: B32B 38/04 Punching, slitting or perforating
• CPC Class Codes: B32B 38/1808 characterised by the laying up of the layers
• CPC Class Codes: B32B 38/1816 Cross feeding of one or more of the layers
• CPC Class Codes: B32B 38/1858 using vacuum
• CPC Class Codes: Y10T 156/1002 with permanent bending or reshaping or surface deformation of self sustaining lamina
• CPC Class Codes: Y10T 156/1051 by folding
• CPC Class Codes: Y10T 156/1067 Continuous longitudinal slitting
• CPC Class Codes: Y10T 156/1075 : of plural laminae from single stock and assembling to each other or to additional lamina
• CPC Class Codes: Y10T 156/108 : Flash, trim or excess removal

Abstract

A method of manufacturing curved composite structural elements can include fabricating a web ply in a flat curve over a removable substrate and laying up the ply on a curved web surface of a manufacturing tool. The method also can include laying up a diagonal ply with fibers oriented at +/−45° from the centerline of the web surface. The method further can include cutting a unidirectional composite tape into segments and laying up the tape segments to form a cross ply with a fiber orientation normal to the centerline of the web surface. One or both edges of the diagonal and cross plies may be folded over one or two sides of the manufacturing tool to form one or two flange surfaces. Additionally, a cap ply can be laid up on one or both flange surfaces using composite tape. The structural element layup can then be inspected and any excess composite material can be trimmed away.

Claims

1. A method comprising the steps of:

forming a 0-degree, planar curved web ply of contiguous, adjoined fiber composite strips by placing the strips to lay contiguously adjoined on a flat surface and in the shape of a planar arc so that the fibers are in a 0-degree direction aligned with a full length of a longitudinal centerline of the planar arc without distortion;

trimming the web ply to conform to the shape of a perimeter of a planar curved web surface of a mandrel, said mandrel having first and second side cap surfaces which meet the web surface to form first and second corners respectively;

laying up the web ply onto the web surface of the mandrel to have 0-degree fiber orientation substantially aligned with the full length of a longitudinal centerline of the web surface; and

laying up a 0-degree cap ply of fiber composite tape onto the first cap surface to form a splice with the web ply along the first corner of the mandrel, the tape comprising a plurality of tape fibers having 0-degree fiber orientation substantially aligned with a longitudinal centerline of the first cap surface, and the splice forming a continuous, substantially 0-degree ply lying across the web surface and the first cap surface.

2. The method of claim 1, further comprising laying up a 0-degree cap ply of fiber composite tape onto the second cap surface to form a second splice with the web ply along the second corner of the mandrel, the tape comprising a plurality of tape fibers having 0-degree fiber orientation substantially aligned with a longitudinal centerline of the second cap surface, and the second splice forming a continuous, substantially 0-degree ply lying across the web surface and the first and second cap surfaces.

3. The method of claim 2, further comprising forming a curved composite structural element by curing the resulting layup comprising the splices.

4. The method of claim 3, wherein the curved composite structural element is an aircraft structural member.

5. The method of claim 4, wherein the aircraft structural member is a floating frame.

6. The method of claim 3, wherein the curved composite structural element comprises a C-shaped cross section.

7. The method of claim 1, further comprising forming a curved composite structural element by curing the resulting layup comprising the splice.

8. The method of claim 7, wherein the curved composite structural element is an aircraft structural member.

9. The method of claim 8, wherein the aircraft structural member is a shear tie.

10. The method of claim 7, wherein the curved composite structural element comprises an L-shaped cross section.

11. The method of claim 1, wherein each strip is a slit composite tape.

12. The method of claim 1, wherein each strip is a prepreg tow.

13. The method of claim 1, wherein the web ply is formed on a removable substrate material.

14. The method of claim 13, further comprising removing the removable substrate material from the trimmed web ply subsequent to laying up the web ply on the web surface of the mandrel.

15. The method of claim 1, further comprising laying up a diagonal ply over the web surface of the mandrel.

16. The method of claim 15, further comprising laying up a cross ply over the web surface of the mandrel.

17. The method of claim 16, further comprising the steps of:

sealing the resulting layup comprising the splice, the diagonal ply, and the cross ply within a vacuum bag to remove trapped air; and

forming a curved composite structural element by curing the sealed layup.

18. The method of claim 17, further comprising inspecting the curved composite structural element for defects.

19. The method of claim 18, further comprising trimming the curved composite structural element.

20. The method of claim 1, further comprising the steps of:

sealing the resulting layup comprising the splice within a vacuum bag to remove trapped air; and

forming a curved composite structural element by curing the sealed layup.

21. The method of claim 20, further comprising inspecting the curved composite structural element for defects.

22. The method of claim 21, further comprising trimming the curved composite structural element.

23. The method of claim 1, further comprising the step of transferring the resulting layup comprising the splice onto a curved, concave manufacturing tool, the curved, concave manufacturing tool having a shape conforming to an external surface of the resulting layup.

24. The method of claim 11, wherein each strip is ⅛

inch wide.

25. The method of claim 12, wherein each strip is between 0.12 inch and 0.25 inch wide when flattened.