Optimering av smidesgeometri för P-fläns på bakre turbinstativ (TEC)

Sammanfattning: This thesis work has been performed at Volvo Aero Corporation in Trollhättan, at the department of “hot structures” involving aircraft engine GP7000. The purpose with the study was to investigate the possibility to reduce size of the forging of flanges on the rear turbine frame when purchasing. Thereto examine the parameters that affect the flanges motion during the manufacturing process. The goal was to provide Volvo Aero with foundation to later bring in slimmed forgings. In order to supply the company with a concrete result the report was limited into studying the P-flange. During the manufacturing process the flanges moves. By measuring the deviation from calculated points on nominal geometry relative to scanned geometry after affecting operations, the motion could be mapped. From these studies two proposals for optimization was presented. The first proposal is based on evening out the tilt caused from the TIG-welding operation. Purchasing tilted forgings would compensate the angle and make room for further savings. If the introduction became a success it could eventually mean that a whole operation (roughing) might be removed. Due to insufficient knowledge about whether the tilt would change as expected after introduction, it requires another analyze after implemented before material can be reduced. The second proposal is based on reducing material solely on the point´s motion. Calculating with four sigma safety (99,379%) on the movements gave information about how much excess material that could be reduced on the forgings. Considerations about whether decreased material would modify the movement pattern have been taken into account. The result shows that 10 % from the bought in forgings can be removed directly. The authors suggest that Volvo Aero begin with the tilt-proposal as a first step in bringing in slimmed forgings. For future work the company could implement the approach taken on this report to the other flanges.