Abstract: A method for laser welding a multiplicity of foils onto a carrier includes arranging the foils one on top of the other to provide a foil stack, folding the foil stack to provide a folded region of the foil stack that protrudes up from two side regions of the foil stack, pressing the side regions against the carrier, and pressing together the side regions toward the folded region. The method further includes welding the foils to one another and to the carrier by directing a laser beam onto the folded region and moving the laser beam along the folded region.

Abstract: The present relates to a method of welding in deep joints in narrow-gap geometry. The two metallic components are arranged next to each other such that there is nearly a zero gap between the two components. The step of joining two metallic components is performed in two stages, the first stage being a root weld and the second stage being a fill up weld. The root weld is completed at the joining of the two discs starting from a middle portion to a point up to which there is still a zero gap between the two discs. From the point there exists a non-zero gap between the two discs up to an outer portion. The filler gap is filled by fill up welding. During fill up welding, a filler wire is melted along with the two discs by using the first source of energy, and to fill the filler gap along with molten material of the two discs.

Abstract: A method for post-weld heat treatment of a without a filler material welded high strength component made of a gamma prime (??) strengthened superalloy can include providing the welded component, heating the welded component by applying a rapid heating-up rate in the range of 20° C./min to 40° C./min during the entire temperature range from room temperature (RT) up to a temperature T1 of at least 1000° C., holding the welded component at T1 and then heating the component by applying a slow heating-up rate of about 5° C./min to a final temperature Tf, then holding the welded component at Tf for a time tf sufficient for at least partially dissolving the gamma prime phase in a weld of the welded component and also in a base material surrounding the weld, and cooling the component with a cooling rate that is greater than or equal to about 20° C./min.

Abstract: An insert element for closing an opening inside a wall of a hot gas path component of a gas turbine includes a plate like body with an opening sided surface. The surface provides at least one first area which projects beyond at least one second area of said surface which surrounds the at least one first area frame-like. The at least one first area is encompassed by a circumferential edge corresponding in form and size to the opening such that the circumferential edge and the opening contour limit a gap at least in some areas, while the at least one second area contacts directly or indirectly the wall of the hot gas path component at a rear side facing away from the hot gas path. The plate like body provides at least a first functional layer-system, providing at least one layer made of heat resistant material, defining the first area of the surface (S).

Abstract: A method is provided for repairing a single crystal turbine blade, which includes an airfoil with a tip having a tip cover plate, tip cooling air holes and a tip crown. The method includes removing the tip crown by manual grinding, thereby preserving the underlying tip cover plate; preparing the tip cooling air holes by manual grinding; closing said prepared tip cooling air holes by manual welding; and building-up a new tip crown by a LMF (Laser Metal Forming) process.

Abstract: The present relates to a method of welding in deep joints in narrow-gap geometry. The two metallic components are arranged next to each other such that there is nearly a zero gap between the two components. The step of joining two metallic components is performed in two stages, the first stage being a root weld and the second stage being a fill up weld. The root weld is completed at the joining of the two discs starting from a middle portion to a point up to which there is still a zero gap between the two discs. From the point there exists a non-zero gap between the two discs up to an outer portion. The filler gap is filled by fill up welding. During fill up welding, a filler wire is melted along with the two discs by using the first source of energy, and to fill the filler gap along with molten material of the two discs.

Abstract: A method is provided for repairing a single crystal turbine blade, which includes an airfoil with a tip having a tip cover plate, tip cooling air holes and a tip crown. The method includes removing the tip crown by manual grinding, thereby preserving the underlying tip cover plate; preparing the tip cooling air holes by manual grinding; closing said prepared tip cooling air holes by manual welding; and building-up a new tip crown by a LMF (Laser Metal Forming) process.

Abstract: A method for repairing a gas turbine component includes: identifying on the gas turbine component (10) a worn out location, where the gas turbine component (10) is damaged; removing the damaged location, thereby creating a missing zone (18); manufacturing an insert, which fits into the missing zone (18); putting the insert into the missing zone (18); adjusting the insert in the gas turbine component (10); and joining the adjusted insert to the gas turbine component (10).

Abstract: The invention relates to a method of post-weld heat treatment of a without a filler material electron beam or laser welded high strength component made of a gamma prime (??) strengthened superalloy based on Ni or Co or Fe or combinations thereof. The method consists of the following steps a) providing the welded component, then b) heating the welded component by applying a rapid heating-up rate in the range of about 20 to 40° C./min during the entire temperature range from RT up to a temperature T1 of at least 1000° C., then c) holding the welded component at T1 and then heating the component by applying a slow heating-up rate of about 5° C./min to a final temperature Tf, then d) holding the welded component at Tf for a time tf, wherein isothermal dwell time tf is sufficient for at least partially dissolving the gamma prime phase in the weld and also in the base material surrounding the weld; then e) cooling the component with a cooling rate of about 20° C.

Abstract: A wear- and oxidation-resistant turbine blade and a method for producing the blade are provided. At least portions of the surface of the main blade section are provided with at least one first protective coating comprised of oxidation-resistant material, the first, oxidation-resistant coating is a metallic coating, which is optionally covered by a ceramic thermal barrier coating. The metallic first protective coating is arranged at least at the inner and outer crown edge of the blade tip, but not at the radially outer blade tip. The radially outer blade tip of the turbine blade is comprised of a second, single- or multi-layer wear- and oxidation-resistant protective coating, which is built up by laser metal forming and is comprised of abrasive and binder materials. The second protective coating on the blade tip overlaps along the outer and/or inner crown edge at least partially with the first, metallic protective coating arranged there.

Abstract: The invention refers an insert element for closing an opening inside a wall of a hot gas path component of a gas turbine. The insert includes a plate like body with an opening sided surface. The surface provides at least one first area which projects beyond at least one second area of said surface which surrounds the at least one first area frame-like. The at least one first area is encompassed by a circumferential edge corresponding in form and size to the opening such that the circumferential edge and the opening contour limit a gap at least in some areas, while the at least one second area contacts directly or indirectly the wall of the hot gas path component at a rear side facing away from the hot gas path. The plate like body provides at least a first functional layer-system, providing at least one layer made of heat resistant material, defining the first area of the surface (S).

Abstract: A lamellar seal for sealing a shaft which rotates around an axis, especially in a gas turbine, includes a multiplicity of lamella (13) which are spaced one beneath the other, arranged in a concentric circle around the axis, and fixed in their position, wherein the lamellae (13) by their surfaces are oriented essentially parallel to the axis. The lamellar seal is improved by the fact that the lamellae (13) have formed-on structures (19, 20, 21) in each case for positioning and retaining the lamellae (13) in the lamellar seal (12), which include one or more laterally projecting support arms (19, 20, 21) which engage in complementarily formed recesses (25, 26) of the end plates (15, 16).

Abstract: A gas turbine engine hot gas component repair method for defects that do not extend through the thickness of the component is provided. First defects are removed by machining a cavity in the surface of a component. Coupons, fittable within the cavities are manufactured, are for example coated with brazing medium on an inner surface and then joined to the component by joining means such as laser metal forming. The joint holds the coupon during later heat treatment, thereby eliminating a need for holding aids. Before heat treatment, a further brazing medium can be applied to the surface of the coupon overlapping onto the component. A single heat treatment, brazing the coupon to the component and, brazing the brazing medium to the outer surface of the coupon can, then be used to complete the repair.

Abstract: A method for repairing an ex-service gas turbine component (10) includes the steps of: removing a damaged section (13) from the gas turbine component (10), manufacturing a 3-D article, which fits in the gas turbine component (10) to replace the removed damaged section (13), and joining the gas turbine component (10) and the 3-D article inserted therein. Reduced cost, improved flexibility and productivity, and simplified handling are achieved by removing the damaged section (13) in the form of a cut-out section along a split line (14) as one single cut-out piece (15), measuring the cut-out piece (15) to obtain the actual non-parametric geometry data set of the cut-out piece (15), and manufacturing the 3-D article based on the geometry data set of the cut-out piece (15).

Abstract: A method for repairing a gas turbine component includes: identifying on the gas turbine component (10) a worn out location, where the gas turbine component (10) is damaged; removing the damaged location, thereby creating a missing zone (18); manufacturing an insert, which fits into the missing zone (18); putting the insert into the missing zone (18); adjusting the insert in the gas turbine component (10); and joining the adjusted insert to the gas turbine component (10).

Abstract: A wear- and oxidation-resistant turbine blade and a method for producing the blade are provided. At least portions of the surface of the main blade section are provided with at least one first protective coating comprised of oxidation-resistant material, the first, oxidation-resistant coating is a metallic coating, which is optionally covered by a ceramic thermal barrier coating. The metallic first protective coating is arranged at least at the inner and outer crown edge of the blade tip, but not at the radially outer blade tip. The radially outer blade tip of the turbine blade is comprised of a second, single- or multi-layer wear- and oxidation-resistant protective coating, which is built up by laser metal forming and is comprised of abrasive and binder materials. The second protective coating on the blade tip overlaps along the outer and/or inner crown edge at least partially with the first, metallic protective coating arranged there.

Abstract: A lamellar seal for sealing a shaft which rotates around an axis, especially in a gas turbine, includes a multiplicity of lamella (13) which are spaced one beneath the other, arranged in a concentric circle around the axis, and fixed in their position, wherein the lamellae (13) by their surfaces are oriented essentially parallel to the axis. The lamellar seal is improved by the fact that the lamellae (13) have formed-on structures (19, 20, 21) in each case for positioning and retaining the lamellae (13) in the lamellar seal (12), which include one or more laterally projecting support arms (19, 20, 21) which engage in complementarily formed recesses (25, 26) of the end plates (15, 16).