Abstract: A method for repairing a discrete damaged portion of an article surface, for example of a laminated composite material, includes applying an uncured repair material at the damaged portion and then subjecting the repair material and the discrete damaged portion to a vacuum to remove air entrapped in the repair material and the discrete damaged portion. One form of the invention uses a vacuum tool comprising an outer wall including an opening there through having a peripheral edge shaped to conform generally with a portion of the article surface about the damaged portion, and gas evacuation means. The tool is combined with a releasable gas seal generally shaped to interface between the peripheral edge and the article surface and release from the article surface.

Abstract: A method for repairing a discrete damaged portion of an article surface, for example of a laminated composite material, includes applying an uncured repair material at the damaged portion and then subjecting the repair material and the discrete damaged portion to a vacuum to remove air entrapped in the repair material and the discrete damaged portion. One form of the invention uses a vacuum tool comprising an outer wall including an opening there through having a peripheral edge shaped to conform generally with a portion of the article surface about the damaged portion, and gas evacuation means. The tool is combined with a releasable gas seal generally shaped to interface between the peripheral edge and the article surface and release from the article surface.

Abstract: A system is provided inside a turbomachine for controlling operational clearance between a turbine rotor and a surrounding turbine shroud. The system comprises a plurality of control rings, integrated into the turbine casing, that are thermally expanded and contracted to control radial positioning of the turbine shroud. Compressor air is directed through internal passages in the rings to cause the expansion and contraction. The system utilizes the pressure and temperature of compressor air, in combination with size, location, and structure of the control rings to match thermal growth of the control rings and turbine shroud to thermal growth of the turbine rotors, thereby controlling clearance.