An Analysis of the Stress Relief Process of Drum Rotors John Moran Conduction Heat Transfer MEAE6630H01 April 13, 2000

Process Rotors EB welded into drums Drums stress relieved in vacuum furnace Heat to 1100 F, hold for 2hrs Static cool Free convection cool Forced convection cool

Approach Collect TC data 2D MARC finite element model Assume a flux function based on known behavior of process and match to TC data Draw conclusions

Temperature profile after heat up period

Temperature profile after soak period

Temperature profile after radiation cool down period

Temperature profile after free convection cool down period

Temperature profile after forced convection cool down period

Conclusions Analysis too crude for quantitative solution but adequate for qualitative solution % Power to bottom heaters should be increased to even out heating Inner bores have slowest response, TC locations do not reflect max  T’s across the part Large  T’s across inner disks may cause warping, detailed study is warranted