An acoustic structure presenting a front surface and a back surface is provided. The acoustic structure includes a support layer comprising the back surface, a honeycomb core comprising a thickness defined between a back and a front, and a plurality of walls that define a plurality of honeycomb cells, wherein the plurality of honeycomb cells extend through the thickness of the honeycomb core opening out toward at least the front, and wherein the back of the honeycomb core is affixed to the support layer, a mesh layer affixed to the front of the honeycomb core, and a knit fabric layer affixed to the mesh layer and conforming to the front surface of the acoustic structure.

Various method for repairing a tire tread are provided. In one embodiment, a method for repairing a tire tread comprises: providing a tire having a tire tread portion wherein the tire tread portion includes a tread element that is at least one of a tread block and a tread rib, and wherein the tread element includes a void resulting from wear or damage of the tire tread portion; removing a material from at least a portion of the tread element adjacent to the void to create a removed material portion, wherein the removed material portion includes a specific shape corresponding to a replacement element; applying an adhesive to at least one surface of the removed material portion; applying the replacement element to the removed material portion; and curing the adhesive.

A method eliminates voids in the bond line and manipulates a thickness of the bond line. This method includes: applying an adhesive at a center of an area of a structure; placing a doubler on the adhesive over the area of the structure, wherein the doubler has a peripheral edge; and maintaining a negative pressure at the peripheral edge of the doubler while simultaneously maintaining a positive pressure at the doubler to purge entrapped gases and control a thickness of the bond line at the peripheral edge of the doubler.

A method eliminates voids in the bond line and manipulates a thickness of the bond line. This method includes: applying an adhesive at a center of an area of a structure; placing a doubler on the adhesive over the area of the structure, wherein the doubler has a peripheral edge; and maintaining a negative pressure at the peripheral edge of the doubler while simultaneously maintaining a positive pressure at the doubler to purge entrapped gases and control a thickness of the bond line at the peripheral edge of the doubler.

A system for repairing polymer structures, for example, polypropylene storage tanks for liquid, includes the application of a unique primer in connection with a plurality of layers of other adhesives to attach a liquid-impermeable elastomeric liner. The system permits the liquid-impermeable elastomeric liner to expand and contract along with the polymer tank, thus resisting separation of the liner from the polymer.

Described are methods and systems for repair of composite components without the use of vacuum bagging. The systems described herein include a composite repair structure with a repair laminate and a film sealant. The film sealant covers the repair laminate to prevent intrusion of air and other volatiles during bonding of the composite repair structure to the composite being repaired. As the film sealant prevents intrusion of air and other volatiles, the composite repair structure can be bonded to the structure to be repaired without the use of a vacuum bag. Thus, vehicle components can be repaired without disassembly from the vehicle.

Described are methods and systems for repair of composite components without the use of vacuum bagging. The systems described herein include a composite repair structure with a repair laminate and a film sealant. The film sealant covers the repair laminate to prevent intrusion of air and other volatiles during bonding of the composite repair structure to the composite being repaired. As the film sealant prevents intrusion of air and other volatiles, the composite repair structure can be bonded to the structure to be repaired without the use of a vacuum bag. Thus, vehicle components can be repaired without disassembly from the vehicle.

A method for repairing a crack in a structure includes mounting a manifold to the structure around the crack. The structure has a nonplanar surface contour that surrounds the crack. The manifold has a base portion, a cover portion, and a plug. The base portion has a grip surface configured to conform to the nonplanar surface contour of the structure. The cover portion is connected to the base portion, and has an injection port and a vent port in fluid communication with a channel aligned to the crack. The injection port transfers a bonding material into and out of the channel. The plug closes and opens the vent port. The method includes filling the channel with the bonding material to direct the bonding material into the crack, and draining the bonding material from the manifold.

A method of repairing a composite blade. The composite blade includes a metal work bonded to a composite part through an adhesive layer. The method includes determining a locally damaged portion of the metal work, and removing a bullet portion corresponding to the locally damaged portion. The method further includes detaching, debonding, and removing a first wing portion from the composite part to obtain a first exposed surface portion. The method further includes detaching, debonding, and removing a second wing portion from the composite part to obtain a second exposed surface portion. The method further includes reconditioning the first and second exposed surface portions to obtain first and second reconditioned surface portions, respectively, and applying first and second adhesive layers to the first and second reconditioned surface portions respectively. The method further includes bonding a metal work patch to the first and second adhesive layers.

Described are methods and systems for repair of composite components without the use of vacuum bagging. The systems described herein include a composite repair structure with a repair laminate and a film sealant. The film sealant covers the repair laminate to prevent intrusion of air and other volatiles during bonding of the composite repair structure to the composite being repaired. As the film sealant prevents intrusion of air and other volatiles, the composite repair structure can be bonded to the structure to be repaired without the use of a vacuum bag. Thus, vehicle components can be repaired without disassembly from the vehicle.