T55 Gas Turbine Engine Bleed Band Actuator Housing Re-Design

The continual replacement of the bleed band actuator caused a supply shortage resulting in production work stoppage. A re-design effort restored the actuator housing through rework modification of a sleeve repair. The re-design substantion is presented along with the qualification test and manufacturing process. Significant value engineering savings and increased supply readiness resulted from the re-design effort for the U. S. Army. However, the re-designed sleeved actuator housing became costly and inefficient over time and subsequently stopped. The overhaul discrepancy is still present on the newer T55 gas turbine engine model. A review of new repair technology available identified another solution that does not generate hazardous industrial waste. That solution is cold spray technology. Cold spray solid state additive technology is evaluated for re-design of the housing as comparison to the existing sleeve re-design. Cost decrease and manufacturing efficiency increase are both a result from this evaluation. Two cold spray powders presented are options for the re-design housing. While both powders provide a better overall solution to the sleeve re-design, the cold spray hard coat powder appears to provide improved wear resistance, e.g. 20 times better than hexavalent chrome plating.