Abstract: A process is provided for repairing a damaged portion of a gas turbine blade comprising: providing a preform comprising a low-melt alloy material and a base alloy material; locating the preform on the gas turbine engine blade damaged portion; and heat treating the preform and the blade such that the preform is brazed to the blade.

Abstract: A superalloy substrate, such as a turbine blade or vane, is fabricated or repaired by laser beam welding to clad one or more layers on the substrate. Laser optical energy is transferred to the welding filler material and underlying substrate to assure filler melting and adequate substrate surface wetting for good fusion. Energy transfer is maintained below a level that jeopardizes substrate thermal degradation. Optical energy transfer to the filler and substrate is maintained uniformly as the laser beam and substrate are moved relative to each other along a translation path by varying the energy transfer rate to compensate for localized substrate topology variations.

Abstract: A method (50) of installing a tip cap (42) onto a turbine blade (20). An open tip is prepared (52) by removing a tip cap from a used blade or during original blade manufacture. A tip cap base sheet (24) is formed (54) to cover at least most of the blade tip surface except for a margin (22). A root pass weld (28) is performed (58) around the periphery of the base sheet, thus welding the base sheet onto the blade tip surface. Cladding (34) is applied (60) to the base sheet and the blade tip surface, thus building and fusing the tip cap onto the blade tip, the tip cap formed of cladding and the base sheet. A squealer ridge (44) may then be formed on the tip cap by additive welding.

Abstract: An apparatus (10) and method for evaluating an effect of a surface presentation angle (A). The apparatus supports a plurality of samples (12) separated by support plates (18) between end plates (22) in a shish kebab arrangement. A groove (34) is formed on each side of each support plate for receiving an edge of each respective sample at a different angle relative to an axis of impingement (32). A clamping mechanism (20) holds the end plates, support plates and samples together in the fixed orientation exposing each sample surface at a different presentation angle, yet at the same distance from a process end effector (30). The sample impingement surfaces are exposed to the process, and the effect of the different surface presentation angles is determined from the samples. Process variables to counter the effects of surface presentation angle may be identified and controlled.

Abstract: A method of build-up welding including depositing of a weld material on a substrate in a series of weld passes in side-by-side relation to form a first weld layer, wherein substantially all weld passes forming the first weld layer are deposited in a first pass direction. Subsequently, a series of weld passes are deposited in side-by-side relation on the first layer to form a second weld layer, wherein substantially all weld passes forming the second weld layer are deposited in a second pass direction opposite to the first pass direction. Each weld pass of each layer may be deposited at a location where it is restrained on no more than one lateral side extending parallel to the weld pass.

Abstract: A method for welding a tube member to a tubesheet includes positioning an open end of a tube member adjacent to a first side of the tubesheet and with the tube member extending through the tubesheet past a second side of the tubesheet. A penetration enhancing compound is applied to an inner side of the tube member at a location adjacent to a junction between an outer side of the tube member and the tubesheet second side. An arc welding operation is performed at the location of the penetration enhancing compound to effect formation of a weld joint at the junction between the tube member outer side and the tubesheet second side.

Abstract: A damaged portion of a superalloy material turbine blade body is removed, forming an excavated recess. A repair splice is formed of a same material with similar mechanical structural properties, having a mating outer profile conforming to the corresponding recess profile. The repair splice is inserted and captured within the recess, so that the blade body and repair splice are mechanically interlocked. Given similarities in mechanical properties of both the blade body and the mechanically interlocked splice the repaired blade's overall mechanical structural properties are similar to those of an undamaged blade. The repair splice is affixed to the blade body so that the interlocking respective portions of each do not separate. Localized affixation and subsequent cosmetic blade surface repair can be performed with softer, low temperature application braze and weld alloys.

Abstract: A process is provided for repairing a damaged portion of a gas turbine blade comprising: providing a preform comprising a low-melt alloy material and a base alloy material; locating the preform on the gas turbine engine blade damaged portion; and heat treating the preform and the blade such that the preform is brazed to the blade.

Abstract: A superalloy substrate, such as a turbine blade or vane, is fabricated or repaired by laser beam welding to clad one or more layers on the substrate. Laser optical energy is transferred to the welding filler material and underlying substrate to assure filler melting and adequate substrate surface wetting for good fusion. Energy transfer is maintained below a level that jeopardizes substrate thermal degradation. Optical energy transfer to the filler and substrate is maintained uniformly as the laser beam and substrate are moved relative to each other along a translation path by varying the energy transfer rate to compensate for localized substrate topology variations.

Abstract: An apparatus (10) and method for evaluating an effect of a surface presentation angle (A). The apparatus supports a plurality of samples (12) separated by support plates (18) between end plates (22) in a shish kebab arrangement. A groove (34) is formed on each side of each support plate for receiving an edge of each respective sample at a different angle relative to an axis of impingement (32). A clamping mechanism (20) holds the end plates, support plates and samples together in the fixed orientation exposing each sample surface at a different presentation angle, yet at the same distance from a process end effector (30). The sample impingement surfaces are exposed to the process, and the effect of the different surface presentation angles is determined from the samples. Process variables to counter the effects of surface presentation angle may be identified and controlled.

Abstract: A method of build-up welding including depositing of a weld material on a substrate in a series of weld passes in side-by-side relation to form a first weld layer, wherein substantially all weld passes forming the first weld layer are deposited in a first pass direction. Subsequently, a series of weld passes are deposited in side-by-side relation on the first layer to form a second weld layer, wherein substantially all weld passes forming the second weld layer are deposited in a second pass direction opposite to the first pass direction. Each weld pass of each layer may be deposited at a location where it is restrained on no more than one lateral side extending parallel to the weld pass.

Abstract: A damaged portion of a superalloy material turbine blade body is removed, forming an excavated recess. A repair splice is formed of a same material with similar mechanical structural properties, having a mating outer profile conforming to the corresponding recess profile. The repair splice is inserted and captured within the recess, so that the blade body and repair splice are mechanically interlocked. Given similarities in mechanical properties of both the blade body and the mechanically interlocked splice the repaired blade's overall mechanical structural properties are similar to those of an undamaged blade. The repair splice is affixed to the blade body so that the interlocking respective portions of each do not separate. Localized affixation and subsequent cosmetic blade surface repair can be performed with softer, low temperature application braze and weld alloys.

Abstract: A method for welding a tube member to a tubesheet includes positioning an open end of a tube member adjacent to a first side of the tubesheet and with the tube member extending through the tubesheet past a second side of the tubesheet. A penetration enhancing compound is applied to an inner side of the tube member at a location adjacent to a junction between an outer side of the tube member and the tubesheet second side. An arc welding operation is performed at the location of the penetration enhancing compound to effect formation of a weld joint at the junction between the tube member outer side and the tubesheet second side.