Space Shuttle Reusable solid Rocket Motor Acturator Bracket Bolted Joint Certification Analysis

摘要

The certification process of the reusable solid Rocket Motors (RSRM) required many unique analyses of which some have been touched on by Webster~1 and Nielsen~2. As the RSRM design is very performance oriented, structural design required the use of lightweight materials whenever possible, and limited over-design. One such analysis is discussed herein which addresses challenges with the actuator bracket bolted joint on the RSRM nozzle. In order to save significant weight, the nozzle compliance ring and actuator bracket, as well as the forward exit cone section, are constructed from aluminum. Obtaining sufficient joint capability was a difficult task when minimizing nozzle weight, but maintaining structural integrity under extreme loading conditions. The RSRM requirements include an actuator stall load which reaches a level of 103, 424 lbf. RSRM requirements also demand that components be certified on an individual basis meaning each bolt required analysis. This required state-of-the-art finite element modeling techniques. This paper describes the approach used in the analyses and gives details on the process used to determine the maximum delta bolt loads and the individual bolt margins of safety.