J. Rabinovich, H & R Technology, Inc., Waltham, MA

Summary:

The leading edges of compressor airfoils, both on individual blades and integral rotors called "blisks," are subject to varying degrees of damage depending upon their service environment. In many cases, blade leading edges loose their aerodynamic shape resulting in loss of engine performance, increased fuel consumption, decreased safety and mission performance. Restoration of the blades to their original pre-damaged contour can provide a cost effective way to reclaim the damaged parts.

Current repair methods employ significant heat during the metal buildup thus causing unacceptable distortions. Moreover, in many instances this excessive heat input creates an excessive porosity between the build-up passes, resulting in rejects and scrapping of components. These methods leave a significant amount of excess material that needs to be machined away in order to achieve the desired shape thus further increasing the cost of repair. Moreover, the existing additive repair techniques do not provide a single automated process in which pre-and post-deposition machining, and a metal deposition process are integrated in a single machine. This drawback further adds to the cost of repaired components.

The presented compressor blade repair methodology utilizes H&R Technology’s patented low heat flat wire laser deposition process, known as PMD™, as applied to the blade restoration.

In this presentation, HRT will discuss recent advances with PMD™ low heat input flat wire metal deposition technology, which encompass the metal deposition and pre-and post machining of components into one integrated system. Implementation of this technology would have significant technical and economic value for a myriad of US Government and commercial industrial applications.