SAMPE Journal - September/October 2013 - (Page 7)

Feature arTicle Manufacturing Overview of a 2.4 Meter (7.9 Foot) Composite Cryotank D.A. McCarville, J.C. Guzman, and J.L. Sweetin The Boeing Company, Seattle, WA J.R. Jackson and L. Pelham NASA Marshall Space Flight Center, Huntsville, AL J. Steensland, M.B. Soden, and C.W. Petersen Janicki Industries, Sedro-Woolley, WA Abstract As part of the Space Technology Game Changing Development Program (GCDP) Composite Cryotank Technology Development (CCTD) contract, Boeing fabricated a 2.4 m diameter test article as a precursor to a 5.5 meter cryotank design, fabrication, and test. This component encompasses several challenging design features: (a) one-piece co-cured/co-bonded spherical geometry with integral skirts, (b) out-of-autoclave curing materials, (c) permeation resistant thin/hybrid ply laminate skins, and (d) thin and thick off-angle slit tape (tow) construction. The component was built on a 24 piece collapsible composite tool using robotic fiber placement. This paper details the tooling and manufacturing flow with an emphasis on process development building block activities. Lessons learned are compiled that will be used to help guide the build of a 5.5 m diameter tank during the next phase of the CCTD contract. Introduction This paper provides an overview of the manufacturing steps and technology development activities associated with the fabrication of a 2.4 m precursor composite cryotank. It does not provide details on testing, structural sizing or component design activities. This component is slated for test at NASA’s Marshall facility in Huntsville Alabama during the first quarter of 2013. The work is an early building block activity that along with the planned 2013 build of a 5.5 m tank is aimed at advancing industry capabilities and reducing the risk of building an 8.4 m full scale test or flight tank. Although the contract is being performed primarily by a single primary contractor, The Boeing Company and partnering tool vendor (Janicki Industries); because of the scale and complexity of the build process, this paper should be of interest to educators, students and multi-discipline manufacturers of composite hardware. able Launch Vehicles (EELV’s)] to help identify and reduce risks associated with scale-up (e.g., cost, schedule, manufacturing, inspection). Future spin-off capabilities may include LH2 vehicle stages, in-space propulsion systems, on-orbit propellant depots, and liquid oxygen (LOX) cryotanks. CCTD Program Background NASA is exploring advanced composite materials and processes to reduce the overall cost and weight of liquid hydrogen (LH2) cryotanks while maintaining the reliability of existing metallic designs. The fundamental goal of the CCTD project is to mature new and innovative cryotank technologies and thereby help enable human space exploration to destinations beyond low earth orbit such as the moon, near-earth asteroids, and Mars1. On the CCTD contract, NASA is working with Boeing to design, manufacture, and test a 5.5 m diameter composite cryotank that incorporates the features and strain levels of an 8.4 m tank2. The goal of this effort is to achieve a 30 percent weight savings and a 25 percent cost savings versus state of the art aluminum-lithium tanks. Designing for 8.4 m and building at 5.5 m ensures that the developed technologies encompass the size range envisioned for future heavy lift vehicles while fitting within existing infrastructures. A 5.5 m cryotank is of sufficient scale [i.e. similar in size to existing Evolved ExpendSAMPE Journal, Volume 49, No. 5, September/October 2013 7 http://www.siltechcorp.com http://www.siltechcorp.com

Table of Contents for the Digital Edition of SAMPE Journal - September/October 2013

SAMPE Journal - September/October 2013
Contents
President’s Message
Technical Director’s Corner
Manufacturing Overview of a 2.4 Meter (7.9 Foot) Composite Cryotank
Welcome SAMPE’s Newest Members
SAMPE Proceedings
Corporate Partners
SAMPE On-Site Training Seminars
CAMX–The Composites and Advanced Materials Expo
Europe News & Views
SAMPE Europe’s SETEC 13 Wuppertal, Germany
Tech Tidbits
Thermoplastic Composites Technologies for Manufacturing Nose Fuselage Structures
Materials & Products
SAMPE Tech 2013|Wichita, KS
Perspectives
High Temperature RTM370 Polyimide Composites Fabricated by RTM: Characterization and Impact Testing
The SAMPE Foundation
SAMPE Tech 2014|Call for Papers
Industry News
Advertiser’s Index
SAMPE Journal Editorial Calender
Resource Center
Membership Application
SAMPE Proceedings Order Form
Industry Events Calendar
Chapter Contacts

SAMPE Journal - September/October 2013