Title: 3D Woven Composite End Ring for SLS Class Structures; Design Development, Manufacturing and Verifications

Authors: Kenneth Segal, Babak Farrokh, David Sleight, Robert Matarese, David Paddock, Robert Allen, Hakan Gokce, and Leon Bryn

DOI: 10.33599/nasampe/c.19.0744

Abstract: The National Aeronautics and Space Administration (NASA) Space Technology and Mission Directorate (STMD) is advancing composite technologies for exploration missions. The Composite Technology for Exploration (CTE) project is chartered to advance light-weight joint concepts for Space Launch System (SLS) class structures. These large structures which can be up to 8.4 meters in diameter, are highly loaded and enable NASA's exploration to the moon, Mars and beyond. Launch vehicle inter-stages, payload fairings, stage adapters, payload attach fittings and the like all use metallic end rings for end attachments. These can be as much as forty percent of the total structure mass. CTE targeted these end rings as potential mass saving structural components. A CTE structure was selected as a point design for mass comparisons. Relevant loads were applied to the point design structural model. Preliminary analysis showed composite end ring mass savings of fifty percent over the baseline metallic design. A variety of designs were traded. Detailed design of 3D woven composite end ring matured through material selection, weave selection, geometric design, analyses, material validations and manufacturing verifications talked about in this paper. A C-Channel design is Resin Transfer Molded (RTM) resulting in a strong and stiff design that is rigid for assembly and provides a bolted interface at mating sections. A Pi-Preform design is co-cured to acreage panels and the C-channel enabling ease of assembly without the need for extreme positional tolerances, and for bonded joint strength. The design development concept advanced is straight 3D woven composite parts for properties validations to show feasibility toward these large highly loaded structures to enable lighter structures allowing more payload mass to reach deep space.

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Conference: CAMX 2019

Publication Date: 2019/09/23

SKU: TP19-0744

Pages: 15

Price: $30.00