Methods of repairing worn blade tips of compressor and turbine blades

Abstract

In a method of repairing worn blade tips of compressor or turbine blades, the worn blade tip (4) is first removed from the remaining blade portion (2) at a standardized height (h). The actual geometry of the end of the remaining blade portion (2) at the height (h) is measured, for example by optical digital image processing means. A repair part (4') is cut from a plate or sheet of repair material having a thickness (d) essentially corresponding to the difference between the nominal finished height (H) of the repaired turbine blade (1) and the standardized height (h) of the remaining blade portion (2) undergoing repair. The repair part (4') is cut to have a contour corresponding to the measured actual geometry of the end of the remaining blade portion (2) at the standardized cut-off height (h), for example using a laser cutting process CNC-controlled by the acquired data representing the actual blade geometry. Finally, the repair part (4') is attached to the end of the remaining blade portion (2), for example by welding or soldering, and preferably by induction soldering with a solder foil (5) interposed between the repair part (4') and the remaining blade portion. The resulting repair is a smooth transition from the remaining blade portion to the repair part, substantially matching the original new blade shape, without requiring finish machining of the joint.

Dependencies are inferred from the claim text.