초록 ▼

A method for repairing a damaged area, referred to as the repair area, of a composite structure comprises steps of: making alignment markings on the repair area; fabricating a pair of alignment templates; preparing the repair area for a hot bonded, vacuum bagged repair; assembling a repair patch; co

A method for repairing a damaged area, referred to as the repair area, of a composite structure comprises steps of: making alignment markings on the repair area; fabricating a pair of alignment templates; preparing the repair area for a hot bonded, vacuum bagged repair; assembling a repair patch; consolidating the repair patch; heating the repair patch; transferring and aligning the repair patch to the repair area; vacuum bagging, heating, and cooling the repair patch for a partial cure at the repair area; heating and cooling the repair patch in an oven; and bonding the repair patch to the repair area.

대표청구항 ▼

1. A method for repairing a damaged repair area of a composite structure, comprising steps of:making alignment markings on the repair area;fabricating a pair of alignment templates;preparing the repair area for a hot bonded, vacuum bagged repair;assembling a repair patch;consolidating said assembled

1. A method for repairing a damaged repair area of a composite structure, comprising steps of:making alignment markings on the repair area;fabricating a pair of alignment templates;preparing the repair area for a hot bonded, vacuum bagged repair;assembling a repair patch;consolidating said assembled repair patch;heating said consolidated repair patch;transferring and aligning said consolidated and heated repair patch to the repair area;vacuum bagging, heating, and cooling said transferred and aligned repair patch at the repair area;removing said vacuum bagged, heated and cooled repair patch from the repair area heating and cooling said removed repair patch in an oven; andbonding said oven heated and cooled repair patch to the repair area. 2. The method of claim 1 further comprising a step, before said step of making alignment markings, of preparing the repair area wherein damaged material is removed from the repair area and a surface of the repair area is cleaned. 3. The method of claim 1 wherein said step of making alignment markings comprises marking a hinge line and a 90° line. 4. The method of claim 1 wherein said fabricating step comprises steps of centering a piece of transparent bagging film over the repair area; and tracing said alignment markings onto said transparent bagging film. 5. The method of claim 1 wherein said preparing step comprises steps of:installing thermocouples in the repair area;removing a flash tape in a bond area of the repair area and leaving the flash tape outside of the bond area; andcovering the repair area with a solid separator film. 6. The method of claim 5 wherein said assembling step comprises:cutting to size plies of fiber-reinforced bismaleimide repair material;fabricating a ply lay-up template;taping a first of said pair of alignment templates on said ply lay-up template;laying up said plies on said first of said pair of alignment templates; andaffixing a second of said pair of alignment templates to said repair material. 7. The method of claim 1 wherein said consolidating step comprises steps of:covering a center area of a plate with insulation;covering said insulation with a heating blanket;placing a thin copper sheet over said heating blanket;covering said copper sheet with a non-porous separator film;transferring said repair patch onto said non-porous separator film;removing one of said pair of alignment templates from said repair patch;placing thermocouples around said repair patch;placing a porous separator film onto said repair patch;placing a pricked non-porous separator film onto said porous separator film;placing a first fiberglass cloth over said pricked non-porous separator film;vacuum bagging said insulation, said heating blanket, said copper sheet, said non-porous separator film, said repair patch with one of said pair of alignment templates, said thermocouples, said porous separator film, said pricked non-porous separator film, and said first fiberglass cloth using a lower vacuum bag;applying a first vacuum to said lower vacuum bag;placing a second fiberglass cloth onto said lower vacuum bag;placing a rigid box onto said second fiberglass cloth wherein said rigid box is substantially centered over said repair patch;placing a third fiberglass cloth over said rigid box;vacuum bagging said rigid box using an upper vacuum bag; andapplying a second vacuum to said upper vacuum bag, wherein said second vacuum is at a level ranging between zero inches to approximately one inch of mercury less than said first vacuum. 8. The method of claim 7 wherein said heating of said consolidated repair patch step comprises:heating said repair patch at a rate of 3° F. per minute to approximately 250° F.;holding said repair patch at approximately 250° F. for approximately 15 minutes;releasing said second vacuum from said upper vacuum bag, opening said upper vacuum bag, and removing said rigid box; said third fiberglass cloth, and said second fiberglass cloth;holding said repa ir patch at approximately 250° F. for approximately 15 minutes; andremoving said repair patch from said lower vacuum bag. 9. The method of claim 6 wherein said transferring and aligning step comprises:transferring said repair patch to the repair area;aligning one of said pair of alignment templates with said alignment markings on the repair area; androtating said repair patch to contact said solid separator film covering the repair area; andremoving said one of said pair of alignment templates from said repair patch. 10. The method of claim 1 wherein said vacuum bagging, heating, and cooling step comprises:placing a precut perforated separator film over the repair patch;placing a fourth fiberglass cloth over said precut perforated separator film;placing a second solid separator film over said fourth fiberglass cloth;placing a heat blanket over said second solid separator film;placing a fifth fiberglass cloth over said heat blanket;vacuum bagging said repair patch;heating said repair patch at a rate of 3° F. per minute to approximately 350° F.;holding said repair patch at approximately 350° F. for approximately 3 hours; andcooling said repair patch at a rate of 3° F. per minute to approximately ambient temperature. 11. The method of claim 1 wherein said heating and cooling in an oven step comprises:marking orientation on the repair patch;removing the repair patch from the repair area;placing the repair patch in an oven;heating said repair patch at a rate of 3° F. per minute to approximately 375° F.;holding said repair patch at approximately 375° F. for approximately 3 hours;heating said repair patch at a rate of 3° F. per minute to approximately 440° F.;holding said repair patch at approximately 440° F. for approximately 6 hours; andcooling said repair patch at a rate of 3° F. per minute to approximately ambient temperature. 12. A method for repairing a damaged repair area of a composite structure, comprising steps of:making alignment markings on the repair area;fabricating a pair of alignment templates;preparing the repair area for a hot bonded, vacuum bagged repair by:installing thermocouples in the repair area,removing a flash tape in a bond area of the repair area and leaving the flash tape outside of the bond area, andcovering the repair area with a solid separator film;assembling a repair patch by:cutting to size plies of fiber-reinforced bismaleimide repair material,fabricating a ply lay-up template,taping a first of said pair of alignment templates on said ply lay-up template,laying up said plies on said first of said pair of alignment templates, andaffixing a second of said pair of alignment templates to said repair material;consolidating said assembled repair patch;heating said consolidated repair patch;transferring and aligning said consolidated and heated repair patch to the repair area by:transferring said repair patch to the repair area,aligning one of said pair of alignment templates with said alignment markings on the repair area,rotating said repair patch to contact said solid separator film covering the repair area, andremoving said one of said pair of alignment templates from said repair patch;vacuum bagging, heating, and cooling said transferred and aligned repair patch at the repair area;removing said bagged, heated and cooled repair patch from the repair area heating and cooling said removed repair patch in an oven; andbonding said oven heated and cooled repair patch to the repair area. 13. The method of claim 12 further comprising a step, before said step of making alignment markings, of preparing the repair area wherein damaged material is removed from the repair area and a surface of the repair area is cleaned. 14. The method of claim 12 wherein said step of making alignment markings comprises marking a hinge line and a 90° line. 15. The method of claim 12 wherein said step of fabricating alignment templates comprises steps of centering a piece of transparent bagging film over the repair area; and tracing said alignment markings onto said transparent bagging film. 16. The method of claim 12 wherein said consolidating step comprises steps of:covering a center area of a plate with insulation;covering said insulation with a heating blanket;placing a thin copper sheet over said heating blanket;covering said copper sheet with a non-porous separator film;transferring said repair patch onto said non-porous separator film;removing one of said pair of alignment templates from said repair patch;placing thermocouples around said repair patch;placing a porous separator film onto said repair patch;placing a pricked non-porous separator film onto said porous separator film;placing a first fiberglass cloth over said pricked non-porous separator film;vacuum bagging said insulation, said heating blanket, said copper sheet, said non-porous separator film, said repair patch with one of said pair of alignment templates, said thermocouples, said porous separator film, said pricked non-porous separator film, and said first fiberglass cloth using a lower vacuum bag;applying a first vacuum to said lower vacuum bag;placing a second fiberglass cloth onto said lower vacuum bag;placing a rigid box onto said second fiberglass cloth wherein said rigid box is substantially centered over said repair patch;placing a third fiberglass cloth over said rigid box;vacuum bagging said rigid box using an upper vacuum bag; andapplying a second vacuum to said upper vacuum bag, wherein said second vacuum is at a level ranging between zero inches through approximately one inch of mercury less than said first vacuum. 17. The method of claim 16 wherein said heating of said consolidated repair patch step comprises:heating said repair patch at a rate of 3° F. per minute to approximately 250° F.;holding said repair patch at approximately 250° F. for approximately 15 minutes;releasing said second vacuum from said upper vacuum bag, opening said upper vacuum bag, and removing said rigid box; said third fiberglass cloth, and said second fiberglass cloth;holding said repair patch at approximately 250° F. for approximately 15 minutes; andremoving said repair patch from said lower vacuum bag. 18. The method of claim 12 wherein said vacuum bagging, heating, and cooling step comprises:placing a precut perforated separator film over the repair patch;placing a fourth fiberglass cloth over said precut perforated separator film;placing a second solid separator film over said fourth fiberglass cloth;placing a heat blanket over said second solid separator film;placing a fifth fiberglass cloth over said heat blanket;vacuum bagging said repair patch;heating said repair patch at a rate of 3° F. per minute to approximately 350° F.;holding said repair patch at approximately 350° F. for approximately 3 hours; andcooling said repair patch at a rate of 3° F. per minute to approximately ambient temperature. 19. The method of claim 12 wherein said heating and cooling in an oven step comprises:marking orientation on the repair patch;removing the repair patch from the repair area;placing the repair patch in an oven;heating said repair patch at a rate of 3° F. per minute to approximately 375° F.;holding said repair patch at approximately 375° F. for approximately 3 hours;heating said repair patch at a rate of 3° F. per minute to approximately 440° F.;holding said repair patch at approximately 440° F. for approximately 6 hours; andcooling said repair patch at a rate of 3° F. per minute to approximately ambient temperature. 20. A method for repairing a damaged repair area of a composite structure, comprising steps of:making alignment markings on the repair area;fabricating a pair of alignment templates by centering a piece of transparent bagging film over the repair area and tracing said alignment markings onto said transparent bagging film;preparing the repair area for a hot bonded, vacuum bagged repair by:installing thermocouples in the repair area,removing a flash tape in a bond area of the repair area and leaving the flash tape outside of the bond area, andcovering the repair area with a solid separator film;assembling a repair patch by:cutting to size plies of fiber-reinforced bismaleimide repair material,fabricating a ply lay-up template,taping a first of said pair of alignment templates on said ply lay-up template,laying up said plies on said alignment template, andaffixing a second of said pair of alignment templates in an alignment template assembly to said repair material;consolidating said assembled repair patch by:covering a center area of a plate with insulation,covering said insulation with a heating blanket,placing a thin copper sheet over said heating blanket,covering said copper sheet with a non-porous separator film,transferring said repair patch onto said non-porous separator film, largest ply down,removing one of said pair of alignment templates from said repair patch,placing thermocouples around said repair patch,placing a porous separator film onto said repair patch,placing a pricked non-porous separator film onto said porous separator film,placing a first fiberglass cloth over said pricked non-porous separator film,vacuum bagging said insulation, said heating blanket, said copper sheet, said non-porous separator film, said repair patch with said alignment template assembly, said thermocouples, said porous separator film, said pricked non-porous separator film, and said first fiberglass cloth using a lower vacuum bag,applying a first vacuum to said lower vacuum bag,placing a second fiberglass cloth onto said lower vacuum bag,placing a rigid box onto said second fiberglass cloth wherein said rigid box is substantially centered over said repair patch,placing a third fiberglass cloth over said rigid box,vacuum bagging said rigid box using an upper vacuum bag, andapplying a second vacuum to said upper vacuum bag, wherein said second vacuum is at a level ranging between zero inches through approximately one inch of mercury less than said first vacuum;heating said consolidated repair patch by:heating said repair patch at a rate of 3° F. per minute to approximately 250° F.,holding said repair patch at approximately 250° F. for approximately 15 minutes,releasing said second vacuum from said upper vacuum bag, opening said upper vacuum bag, and removing said rigid box; said third fiberglass cloth, and said second fiberglass cloth,holding said repair patch at approximately 250° F. for approximately 15 minutes, andremoving said repair patch from said lower vacuum bag;transferring and aligning said consolidated and heated repair patch to the repair area by:transferring said repair patch to the repair area,aligning said alignment template assembly with said alignment markings on the repair area,rotating said repair patch to contact said solid separator film covering the repair area, andremoving said alignment template assembly from said repair patch;vacuum bagging, heating, and cooling said transferred and aligned repair patch at the repair area by:placing a precut perforated separator film over the repair patch,placing a fourth fiberglass cloth over said precut perforated separator film,placing a second solid separator film over said fourth fiberglass cloth,placing a heat blanket over said second solid separator film,placing a fifth fiberglass cloth over said heat blanket,vacuum bagging said repair patch,heating said repair patch at a rate of 3° F. per minute to approximately 350° F.,holding said repair patch at approximately 350° F. for approximately 3 hours, andcooling said repair patch at a rate of 3° F. per minute to approximately ambient temperature;removing said vacuum bagged, heated and cooled repair patch from the repair area heating and cooling said removed repair patch in an oven by:marking orientation on the repair patch;removin g the repair patch from the repair area,placing the repair patch in an oven,heating said repair patch at a rate of 3° F. per minute to approximately 375° F.,holding said repair patch at approximately 375° F. for approximately 3 hours,heating said repair patch at a rate of 3° F. per minute to approximately 440° F.,holding said repair patch at approximately 440° F. for approximately 6 hours, andcooling said repair patch at a rate of 3° F. per minute to approximately ambient temperature; andbonding said oven heated and cooled repair patch to the repair area. 21. The method of claim 20 further comprising a step, before said step of making alignment markings, of preparing the repair area wherein damaged material is removed from the repair area and a surface of the repair area is cleaned. 22. The method of claim 20 wherein said step of making alignment markings comprises marking a hinge line and a 90° line.