Evaluation of the high pressure oxidizer turbopump (HPOTP) vacuum drying procedures

Tests carried out on the HPOTP to determine the effects of surface finish on the rate at which water vapor could be removed from the bearing/spacer cavity are described. Data from these tests are used to evaluate the effects of a lower drying temperature on the flow rate of water vapor from the bearing/spacer cavity as well. It was found that, if the normality nut is torqued, there is no evidence of moisture entering the bearing/spacer cavity from external sources.