Phil MottAMS-02 Phase II Safety Review1 Vacuum Case Mechanical Design Alpha Magnetic Spectrometer (AMS) - 02 Phase II Flight Safety Review Vacuum Case Mechanical Design Phil Mott May 21-25, 2007

Phil MottAMS-02 Phase II Safety Review2 Vacuum Case Overview  The Vacuum Case (VC) is a structural member of the USS-02 and supports the superconducting cryogenic magnet. This is regardless of the pressure state.  Two identical Vacuum Cases are being built:  Structural Test Article (STA)  Flight  The VC weighs 1,576 lbs and is approximately 9 feet in diameter by 5 feet high.  Vacuum Case Major Components:  Upper Conical Flange  Lower Conical Flange  Upper Support Ring  Lower Support Ring  Inner Cylinder  Outer Cylinder

Phil MottAMS-02 Phase II Safety Review3 Vacuum Case Overview (cont.)  The Vacuum Case attaches to the USS-02 at 10 locations:  8 Interface Plate locations (4 Upper & 4 Lower)  2 Diagonal Struts (Upper)  The superconducting cryogenic magnet is being designed and fabricated by ETH/Space Cryomagnetics Ltd. (SCL) in Culham, England.  The magnet is supported inside the VC by 16 straps attached to the Upper & Lower Support Rings. (The straps will be covered in a later presentation.)  There are 25 Feedthru Ports, not including the strap ports, that are used for Cryocoolers, Cryocooler Access Ports, Fill Ports, Vent Ports, Burst Discs, Current Leads, and cable/tube routing into and out of the Vacuum Case.  Feedthru Ports that are not used will be sealed with a blank cover plate.  All O-Ring joints are sealed with a double O-Ring configuration.  A test port is located between each O-Ring for individual leak checks

Phil MottAMS-02 Phase II Safety Review4 Vacuum Case (Shipping Configuration) Flight Shown – STA (Flight Backup) Identical CLEVIS PLATE 2X OUTER CYLINDER UPPER SUPPORT RING UPPER INTERFACE PLATE 4X LOWER INTERFACE PLATE 4X LOWER SUPPORT RING STRAP PORT 16X ELECTRICAL/PLUMBING/ CRYOCOOLER PORT 25X CONICAL FLANGE 2X INNER CYLINDER – not installed in this configuration

Phil MottAMS-02 Phase II Safety Review5 SUPERFLUID HELIUM TANK MAGNET RACETRACK COIL (DIPOLE COIL ROTATED 90 o ) VACUUM SPACE 1 x TORR SUPER INSULATION & VAPOR COOLED SHIELDS Vacuum Case Cross Section UPPER CONICAL FLANGE UPPER SUPPORT RING UPPER INTERFACE PLATE OUTER CYLINDER INNER CYLINDER OUTER JOINT INNER JOINT LOWER SUPPORT RING LOWER INTERFACE PLATE LOWER CONICAL FLANGE

Phil MottAMS-02 Phase II Safety Review6 Flight Vacuum Case with Magnet

Phil MottAMS-02 Phase II Safety Review7 Vacuum Case Assembly with Misc Attachments

Phil MottAMS-02 Phase II Safety Review8 STA Vacuum Case

Phil MottAMS-02 Phase II Safety Review9 STA Vacuum Case with CMR installed

Phil MottAMS-02 Phase II Safety Review10  Qualification Spin Form  Al 2219-T62 Spin Forming  Original plate was Al 2219-T0 2.25” thick  Plate is spin formed, solution heat treated, and aged to final condition.  Spin Form procedures were reviewed and approved by NASA/ES.  Material tensile test samples were taken from throughout the blank.  Both L and LT directions were tested. 10 locations for each direction.  All test samples exceeded MIL- HDBK-5 values for Al 2219-T62 plate. Conical Flange Qualification

Phil MottAMS-02 Phase II Safety Review11  Spin Form Blank Tests (for all production blanks)  Electrical Conductivity Test per AMS places on both flanges  Hardness Test per AMS places on both flanges  Tensile Test per ASTM B557 L & LT directions 4 places on both flanges Conical Flange Spin Form Blanks

Phil MottAMS-02 Phase II Safety Review12  Total spin form blanks: 7  All 7 spin form blanks were processed identical to the qualification spin formed blank.  Final machined parts are dye penetrant inspected. Conical Flange

Phil MottAMS-02 Phase II Safety Review13  Al 7050-T7451 Rolled Ring Forging.  Forging Size: OD = ID = H =  Forging requirements and inspection data were reviewed and approved by NASA/ES.  Additional tensile samples were taken from both ends of the forging for verification.  Ring stiffened structure. Outer Cylinder

Phil MottAMS-02 Phase II Safety Review14  Al 2219-T851 Rolled Ring Forging.  Forging requirements and inspection data were reviewed and approved by NASA/ES.  Monocoque structure.  Initial machining has been completed. Inner Cylinders are left long and completed at assembly.  Final machining includes machining to the proper length, with weld shrinkage allowance, and machining the weld groove. Inner Cylinder

Phil MottAMS-02 Phase II Safety Review15  Al 7050-T7451 Rolled Ring Forging.  Forging Size: OD = ID = H =  Forging requirements and inspection data were reviewed and approved by NASA/ES.  Additional tensile samples were taken for forging verification.  One Forging has been cut up and used for material tests.  The Support Rings are the primary structure for the VC  All 16 straps attach to the Support Rings.  All Feedthru Ports are located in the Support Rings. Upper & Lower Support Rings

Phil MottAMS-02 Phase II Safety Review16 Interface Plates / Clevis Plates  Interface Plates  Al 7050-T7451 Plate  Clevis Plates  CRES A286

Phil MottAMS-02 Phase II Safety Review17 Strap Port  Closeout Cap Mechanical Attachment  UNJF  Double O-Ring joint  Viton, 75 Durometer  Test Port between O-Rings SUPPORT RING STRAP CLOSEOUT CAP STRAP ASSEMBLY O-RINGS (TEST PORT NOT SHOWN IN THIS VIEW)

Phil MottAMS-02 Phase II Safety Review18 Strap Port

Phil MottAMS-02 Phase II Safety Review19 Feedthru Ports & Cryocooler Ports  Mechanical Attachment  UNJF  Double O-Ring joint  Viton, 75 Durometer  Test Port between O-Rings O-RING TEST PORT (HEX PLUG NOT SHOWN FOR CLARITY) ORIENTATION & LOCATION WILL VARY DEPENDING ON THE ATTACHED COMPONENT OUTER CYLINDER O-RINGS SUPPORT RING (UPPER OR LOWER) MATING COMPONENT VACUUM CASE FEEDTHRU PORT

Phil MottAMS-02 Phase II Safety Review20 Feedthru Ports & Cryocooler Ports

Phil MottAMS-02 Phase II Safety Review21 Outer Joint  Double O-Ring bolted joint.  Mechanical attachment:  Conical Flange, Upper: UNJF  Outer Cylinder, Upper: UNJF  Outer Cylinder, Lower: UNJF & UNJF  Conical Flange, Lower: UNJF  Fasteners are wet installed with Super Korpon at final assembly in England.  O-Ring material is Viton, 75 Durometer.  Test ports between each O-Ring for individual leak checks.

Phil MottAMS-02 Phase II Safety Review22 Outer Joint CONICAL FLANGE SUPPORT RING OUTER CYLINDER O-RING TEST PORT TYPICAL O-RING CONFIGURATION FOR SUPPORT RING TO OUTER CYLINDER AND SUPPORT RING TO CONICAL FLANGE VACUUM SPACE HEX PLUG TO SEAL TEST PORT O-RING O-RINGS INTERFACE PLATE

Phil MottAMS-02 Phase II Safety Review23 Inner Joint  Welded Joint – U Groove Design, 3 Pass.  O-Ring joint not possible due to design constraints on both sides of the joint.  Joint is designed for 3 welds – Initial plus 2 contingencies.  Weld crown will be shaved flush to accommodate ultrasonic inspection.  Three complete closeout welds will take place prior to the closeout weld on the Flight Assembly:  First Article (initial & 1 re-weld)  STA at vendor’s facility for pressure and leak tests.  STA at SCL in Culham, England.

Phil MottAMS-02 Phase II Safety Review24 Inner Joint UPPER or LOWER CONICAL FLANGE INNER CYLINDER MAGNET KEEP-IN ZONE 5/16 WELD PREP COMPLETED WELD

Phil MottAMS-02 Phase II Safety Review25 First Article Weld at VC Vendor

Phil MottAMS-02 Phase II Safety Review26 STA VC Weld at Vendor

Phil MottAMS-02 Phase II Safety Review27 STA VC Weld at SCL

Phil MottAMS-02 Phase II Safety Review28 Closeout Weld Inspection  Joint design does not allow for x-ray inspection of the weld  Weld is visually and dye penetrant inspected.  Weld is ultrasonically inspected using a phased array system. The STA weld at the vendor was inspected manually.  Both methods have been qualified to MSFC-SPEC-504C using flat plates and the First Article.  The STA weld at the vendor required 3 minor repairs.  No repairs were required for the final STA weld in England.

Phil MottAMS-02 Phase II Safety Review29 Vacuum Leak Tests  Both the Flight and STA VC’s were vacuum tested at the vendor. Both met the requirement of 10-6 torr.  Each O-Ring was individually tested.  Helium leak rate for both VC’s met the spec.  STA VC was leak checked again at SCL after the Cold Mass Replica was installed.

Phil MottAMS-02 Phase II Safety Review30 Proof Pressure Tests  The STA VC has been successfully proof pressure tested with argon at the vendor and at SCL after welding.  Proof pressure: 1.8 atm absolute (26.5 psi). [1.0 x MDP]  Flight VC to be proof pressure tested after the magnet is installed and the closeout weld completed.