Fixes J Kerby For my many colleagues who
Fixes J. Kerby For my many colleagues who have contributed to this effort (Ranko Ostojic, Cedric Garion, Tom Page, Thierry Renaglia, Herve Prin, Bob Wands, Frederic Gicquel, Ingrid Fang, Juan Carlos Perez, Tom Nicol, Sandor Feher, Tatsu Nakamoto, Peter Limon, Glyn Kirby, Paul Olderr, Tom Peterson, Jim Strait, Vadim Kashikin…and anyone else I have inadvertently forgotten…) 24 -25 Inner Triplet Review - J Kerby
Outline o o o Review of event Requirements for a fix Proposal Supporting Calculations Vacuum Loading Alternative Restraint Design 24 -25 Inner Triplet Review - J Kerby 2
Non IP end of Q 1, looking toward IP The Xb, XBt, V EE and FF lines, and beam screen lines were not pressurized during the 27 Mar test 24 -25 Inner Triplet Review - J Kerby 3
o o Tables are the full load cases IF all lines were pressurized to MAWP 27 March test the pumping and shield lines were not pressurized, and failure was at 20 bar n n Q 1 load 115 k. N Q 3 load 93 k. N 24 -25 Inner Triplet Review - J Kerby 4
Q 3 94 k. N Q 1 115 k. N 24 -25 Inner Triplet Review - J Kerby 5
Cold Mass Support o o A ‘fixed’ and ‘free’ spider support Invar rod connecting the two to share support 24 -25 Inner Triplet Review - J Kerby 6
Geometry was drawn directly from the CAD model. The bellows at the interconnections between cold masses were simulated with spring elements having a total stiffness of 5500 lbs/in at each interconnection. Moments due to the L line bellows were estimated, and are reacted w/ much longer lever arm of the spacing of the supports, so are a small effect in these analyses. Elements are second-order hexahedral and tetrahedral solids. A total of 500 thousand elements and 600000 nodes were used. 24 -25 Inner Triplet Review - J Kerby 7
Meshing of the supports was refined to include three elements through the half-inch thickness of the G 11. The G 11 was treated as orthotropic; in the plane of the support (the xy plane in the analysis) bending is resisted primarily by the tension or compression of the relatively stiff glass fibers; the Young's modulus is dominated by the glass, and was set to 3 e 6 psi in both the x and y directions. For the z-direction (through the thickness), loads are perpendicular to the glass fibers, and the stiffness is influenced more strongly by the epoxy matrix; a reduced modulus of 1 e 6 psi was used for this direction. Note that while this is technically "orthotropic", it really assumes isotropy in the xy plane. 24 -25 Inner Triplet Review - J Kerby 8
Q 1 - Q 2 - full 20 bar load (all lines) bellows - 1920 lbs 30700 lbs Q 1 IP sliding support - 8760 lbs fixed support - 20100 lbs bellows - 1654 lbs bellows – 1920 lbs Q 2 sliding support - 65 lbs fixed support - 150 lbs IP sliding support - 55 lbs 24 -25 Inner Triplet Review - J Kerby 9
Q 3 – full 20 bar load (all lines) 25800 lbs bellows - 1654 lbs Q 3 sliding support - 7330 lbs IP fixed support - 16900 lbs 24 -25 Inner Triplet Review - J Kerby 10
Pressure Test Summary o With Shield and Xb lines empty, actual loads 84% of 20 bar load in model…results linearly scaled for now: n n n o Q 1 fixed support fails at 16, 950 lbs/75. 4 k. N (7. 5 mm); then propagates to Q 1 free support Q 3 fixed support being checked at 14250 lbs/63. 3 k. N (6. 4 mm); Q 3 free support shows no signs of damage Q 2 appears unaffected DFBX damage not from interaction with Q 3 24 -25 Inner Triplet Review - J Kerby 11
Requirements for a Fix o o o In Situ Does not move fix point of the assemblies React loads with sufficient stiffness to limit deflection – 150 k. N design load (slide 4) Acts at any temperature 300 K to 2 K Focus on implementation in Q 1—Q 3 solution tuned for length will then accommodate 24 -25 Inner Triplet Review - J Kerby 12
Fix Points Internal heat exchanger D 1 LBX FP Cold Mass. Vacuum Vessel Q 3 DFBX Fixed Point Triplet. Tunnel Floor MQXA Fixed Point HX -Cold Mass Q 2 B Q 2 A MQXB Tie Rods Linking Vacuum Vessels External heat exchanger (HX) Q 1 MQXA Jacks (longitudinal) 38490 24 -25 Inner Triplet Review - J Kerby 13
Q 1 24 -25 Inner Triplet Review - J Kerby 14
Q 1 Corrector Containment MQXA 24 -25 Inner Triplet Review - J Kerby 15
Q 3 24 -25 Inner Triplet Review - J Kerby 16
Q 3 MQXA 24 -25 Inner Triplet Review - J Kerby Corrector Containment 17
24 -25 Inner Triplet Review - J Kerby 18
Allowable Deflection of Support o o From failure analysis support fails at deflection of 7. 5 mm (6. 4 mm borderline) System Analysis from Q 1 -Q 2 -Q 3 Cooldown deflection 1. 8 mm in Q 2 free spiders (all tested, ok) Current ongoing tests 24 -25 Inner Triplet Review - J Kerby 19
Cooldown / 20 bar loads – Q 1/Q 2 35 k. N (27 k. N) bellows - 7940 lbs (6000 lbs) 30700 lbs (0 lbs) Q 1 IP sliding support - 5560 lbs (-3190 lbs) fixed support - 17220 lbs 77 k. N (-2840 lbs) (-13 k. N) 35 k. N (27 k. N) bellows - 7770 lbs (6115 lbs) Q 2 10 k. N (10 k. N) 25 k. N (-14 k. N) bellows – 7940 lbs (6000 lbs) IP sliding support - 2260 lbs fixed support - 60 lbs (-86 lbs) (2195 lbs) 137 k. N (0 k. N) 35 k. N (27 k. N) sliding support - 2250 lbs 10 k. N (2300 lbs) (10 k. N) 0 k. N (0 k. N) 24 -25 Inner Triplet Review - J Kerby 20
Cooldown / 20 bar loads – Q 3 115 k. N (0 k. N) 25800 lbs (0 lbs) bellows - 7770 lbs (6115 lbs) Q 3 sliding support - 4140 lbs 18 k. N (-3230 lbs) (-14 k. N) o o o 35 k. N (27 k. N) IP fixed support - 14030 lbs (-2826 lbs) 62 k. N (-13 k. N) Contraction of cold mass interconnect bellows Q 1 -Q 2 and Q 2 -Q 3 reacts portion of quench load Further models move from full triplet to Q 1 only w/ load of interconnect bellows included W/ cooldown, free support pulled toward fixed support by Invar tie rod (Q 1/Q 3 = ~0. 8 mm, Q 2 = 1. 8 mm) 24 -25 Inner Triplet Review - J Kerby 21
Allowable Deflection of Support o Continued longitudinal studies of supports n Push tests in Bat 181 of Q 1 / Q 2 / Q 3 o o System stiffness of 14. 2/18. 0/14. 2 k. N/mm by calculation Measured 14. 8/23. 3/20. 0 k. N/mm (Herve, tuesday) Material properties in model stiffer than directly measured in tests @CERN Note load sharing between fixed and free support is a weak function of this modulus—failure load of Q 1 fixed support changes <10% 24 -25 Inner Triplet Review - J Kerby 22
Allowable Deflection of Support o Testing / modeling to failure of individual supports ongoing n n n o The cold mass provides a rotational constraint on the support and lug which does not exist in the test fixture (currently) Initial tests allowed rotation, deflection without failure or delamination of 6 mm at 8 k. N load applied to lug, but deflection shape not same as installed Initial modeling results ongoing to understand result before proceeding to failure tests Deflection of 2 mm used as allowable, not including ‘slip’ of fixed support 24 -25 Inner Triplet Review - J Kerby 23
Cartouche / Cartridge o o o Affixed at Q 1 non-IP end; Q 3 IP end Transfer load at all temperatures Limits support deflections 24 -25 Inner Triplet Review - J Kerby 24
Pieces…. Cold Mass Bracket, mechanically and thermally attaches AL cylinder to cold mass volume Vacuum vessel bracket, transfers Invar load to Vacuum Vessel Cartridge, Invar rod centered in Al tube 24 -25 Inner Triplet Review - J Kerby 25
o o Four cartridges +/- 331 mm horizontally; +174/-89 mm vertically Utilizes open areas in Cryostat volumes Bracket analysis to vacuum vessel continuing, optimization for heat load, assembly and bending of flange 24 -25 Inner Triplet Review - J Kerby 26
o 1. 3 -1. 4 m thickwall Al Tube, 60 mm. OD 40 mm. ID n n n o Polished or plated for lower emissivity Captured by cold mass bracket for load transfer and thermalization In compression when loaded ~1. 6 m Invar rod, 30 mm diameter n n necked at warm end for thermalization to shield Torqued at assembly for load distribution Could include GRP spacer to cut heat load to vacuum vessel bracket Connected to Al tube through SS shoulder threaded joint at far end Centered 2 places along length 24 -25 Inner Triplet Review - J Kerby 27
Q 1 Cartridge Modeling o o Two mechanical models created; optimization ongoing but looks very promising Bracket to cold beefed up in this iteration; increase thermal coupling and reduces deflections 24 -25 Inner Triplet Review - J Kerby 28
Q 1 Cartridge Modeling o Cartridge applied to Q 1 model including bellows for: n n n Warm 25 bar pressure test load Cold, 20 bar quench load Figure 1. Finite Element Model of Q 1 with Cartridge 24 -25 Inner Triplet Review - J Kerby 29
24 -25 Inner Triplet Review - J Kerby 30
Q 1 Cartridge, 25 bar pressure test bellows - 360 lbs 2 k. N 38400 lbs Q 1 171 k. N IP cartridge - 32300 lbs 144 k. N fixed support - 3990 lbs 18 k. N sliding support - 1720 lbs 8 k. N Figure 2. Forces on Components due to 25 Bar Warm Pressure Test Load 24 -25 Inner Triplet Review - J Kerby 31
Q 1 Cartridge, Cooldown bellows - 6050 lbs 27 k. N 0 lbs Q 1 0 k. N IP cartridge - 1210 lbs 5 k. N fixed support - 2000 lbs 9 k. N sliding support - 2830 lbs 13 k. N Figure 3. Forces on Components due to Cooldown 24 -25 Inner Triplet Review - J Kerby 32
Q 1 Cartridge, cooldown + 20 bar bellows - 6340 lbs 28 k. N 30700 lbs Q 1 137 k. N IP cartridge - 24600 lbs 109 k. N fixed support - 1190 lbs 5 k. N sliding support - 1460 lbs 6 k. N Figure 4. Forces on Components due to Cooldown and 20 Bar Pressure Load 24 -25 Inner Triplet Review - J Kerby 33
Q 1 Cartridge, Deflections o o o Load per cartridge: 36 k. N (warm test, 25 bar evenly split) Al tube stress (3300 psi / 8600 psi ASME allowable) (22. 7 MPa/59 MPa allowable) Invar peak cross section (16600 psi / 21600 psi) (114 MPa / 148 MPa) (Allowable – 3 to ultimate or 2 to yield of annealed Invar) 24 -25 Inner Triplet Review - J Kerby 34
Cartridge Initial Thermal Analysis o o o o Cold mass at 2 K 50 K Heat intercept at the end of the invar rod 50 K Radiation of invar on inner surface of Al tube Thermal connection of the cold end of the Al tube with the cold mass (SS support too resistive otherwise) Vacuum vessel at 293. 15 K Radiation to the cold mass from the brackets welded to the vacuum vessel All interior surfaces with radiation condition have an emmissivity of. 05 which is standard with silver plating Al 6061 used instead of 6082 because material properties were not available 24 -25 Inner Triplet Review - J Kerby 35
Boundary Conditions 24 -25 Inner Triplet Review - J Kerby 36
Steady State @ 2 K o Loads per magnet n n o 11. 72 W to the vacuum vessel. 23 W to the cold mass 10. 5 W at the 50 K heat intercept 1 W radiation cooling on the brackets Revised (larger at warm end) Invar rod diameter gives n n 29 W to 50 K heat intercept Vacuum flange cooled to 14. 3 C 24 -25 Inner Triplet Review - J Kerby 37
longitudinal deformation 24 -25 Inner Triplet Review - J Kerby 38
Aluminum tube temperature 24 -25 Inner Triplet Review - J Kerby 39
Invar rod temperature 24 -25 Inner Triplet Review - J Kerby 40
Vacuum vessel flange temperature 24 -25 Inner Triplet Review - J Kerby 41
Cooldown o Hypothesis: n n o 4 days @ 50 K/day, then 4 days stable Uniform temperature of cold mass No thermal radiation taken into account No heat intercept on the invar rod Need to confirm the cartridge is well enough thermalized to the cold mass at all times and upset conditions 24 -25 Inner Triplet Review - J Kerby 42
Cooldown Initial Results o o Results for first 200 K of cooldown Length optimization ongoing Results still being checked Real wave smoothed w/ cartridge located at opposite end of Q 1 or Q 3 from cryo entry 24 -25 Inner Triplet Review - J Kerby 43
Magnetic Model settings The same low-carbon steel properties for MQXA and MCBX yokes; The rods, 34 mm in diameter also have properties of lowcarbon steel; Nominal current in MQXA coil (I=7149 A, G=215 T/m); Nominal current in both MCBX coils (I=550 A, Bx=By≈3. 3 T); No planes of symmetry within the model. 24 -25 Inner Triplet Review - J Kerby 44
Magnetic field in the iron 24 -25 Inner Triplet Review - J Kerby 45
Total forces on the rods Rod # 1 2 3 4 Fx, N -33. 8 6. 1 49. 2 -32. 5 Fy, N -13. 7 -8. 6 10. 2 18. 7 F z, N 0. 8 0. 1 0. 8 0. 5 Rod numbering corresponds to quadrant numbering in XY (transverse) plane; Z longitundal here 24 -25 Inner Triplet Review - J Kerby 46
Magnetic field distortions Calculated as the field difference between two models - with and without iron rods. Identical meshes, boundary conditions and material properties (except for the rods). Harmonics are presented at 17 mm reference radius in absolute units (T). 24 -25 Inner Triplet Review - J Kerby 47
Field distortions: dipole 24 -25 Inner Triplet Review - J Kerby 48
Field distortions: integral n An, T m Bn, T m 1 1. 04 E-03 7. 35 E-04 2 3. 99 E-06 3. 94 E-06 3 1. 28 E-06 -3. 34 E-05 4 1. 44 E-07 -1. 33 E-07 5 -4. 75 E-07 2. 08 E-07 6 -6. 84 E-09 -3. 71 E-09 7 3. 25 E-09 4. 56 E-11 8 4. 21 E-11 1. 65 E-10 9 -1. 23 E-10 1. 16 E-10 10 -4. 48 E-12 -1. 20 E-12 11 6. 20 E-12 -2. 31 E-12 24 -25 Inner Triplet Review - J Kerby 49
Cartridge Initial Analysis Cartridge looks very promising, and is the proposed solution o o o Worst case Q 1 spider support longitudinal deflection < 2 mm limit Worst case Q 1 spider load < ¼ load that caused failure during recent pressure test Does not move magnet fix point n o o In fact fixes Q 1 / Q 3 better than currently Magnetic effect negligible Design is ongoing to look at: n n n Length; diameter of rod (not 10% effect in various models) Steady state thermalization BC’s Thermal performance under upset / transient conditions Attachment details to cold mass (corrector containment volume shell) Attachment details to vacuum vessel, including effect on O ring groove due to o o n n Cartridge bracket / tie rod ear deflections Cooling of the Vacuum Vessel due to additional heat leak Q 3 attachment Consolidation of design variants and anlayses 24 -25 Inner Triplet Review - J Kerby 50
Vacuum Loads to Ground 24 -25 Inner Triplet Review - J Kerby 51
25 Bar load; no transverse load on jacks o 38400 lbs 171 k. N Vacuum Vessel Deflections n n n V 1 8. 4 mm to IP V 2 4. 6 mm to IP V 3 0. 4 mm to IP tot rod force = 38400 lbs V 1 I P 171 k. N tot rod force = 38400 lbs V 2 171 k. N I P tot rod force = 38400 lbs 135 k. N tot rod force = 8100 lbs 36 k. N 24 -25 Inner Triplet Review - J Kerby 30300 lbs V 3 I P tot rod force = 38400 lbs 171 k. N 52
25 bar load; transverse load ok on jacks o o Jacks assumed = 64 k. N/mm, IP end each vessel only Vacuum Vessel Deflections n n n V 1 2. 5 mm to IP V 2 0. 8 mm to IP V 3 0. 6 mm from IP 38400 lbs 171 k. N tot rod force = 19670 lbs I P V 1 88 k. N jack force = 83 k. N 18730 lbs tot rod force = 13940 lbs V 2 62 k. N 26 k. N tot rod force = 12110 lbs 54 k. N 24 -25 Inner Triplet Review - J Kerby tot rod force = 19670 lbs I P 88 k. N jack force = 5730 lbs 135 k. N 30300 lbs V 3 I P tot rod force = 13940 lbs 62 k. N jack force = 4250 lbs 19 k. N 53
25 bar load + Vacuum load (+bellows); no transverse load on jacks o Vacuum Vessel Deflections n n n o V 1 4. 3 mm to IP V 2 2. 0 mm to IP V 3 0. 4 mm from IP Vac Bellows makes ~5% change in deflections in 2 previous cases 38400 lbs 171 k. N 100 k. N tot rod force = 22600 lbs 2 k. N bellows force = 500 lbs V 1 I P 100 k. N tot rod force = 22600 lbs V 2 bellows force = 500 lbs I P bellows force = 500 lbs 2 k. N 135 k. N 32 k. N 1 k. N 30300 lbs tot rod force = 7100 lbs bellows force = 100 lbs V 3 I P 100 k. N tot rod force = 22600 lbs bellows force = 500 lbs 2 k. N
25 bar load + Vacuum load; transverse load ok on jacks 38400 lbs 171 k. N o o Jacks assumed = 64 k. N/mm, IP end each vessel only Vacuum Vessel Deflections n n n tot rod force = 12600 lbs 56 k. N I P V 1 bellows force = 300 lbs 1 k. N jack force = 10200 lbs 45 k. N tot rod force = 12600 lbs 56 k. N 46 k. N = 10400 lbs V 1 1. 5 mm to IP V 2 0. 3 mm to IP V 3 0. 7 mm from IP bellows force = 220 lbs 1 k. N I P V 2 jack force = 2280 lbs 10 k. N bellows force = 300 lbs 1 k. N 135 k. N 30300 lbs tot rod force = 14450 lbs 64 k. N 1 k. N V 3 I P bellows force jack force = 5080 lbs = 150 lbs 23 k. N tot rod force = 10400 lbs 46 k. N bellows force 1 k. N 19 k. N = 220 lbs
Tie Bar / Tunnel Jacks o o A model exists that can be used to predict load sharing The transverse stiffness and load carrying capability of the jacks is in parallel w/ the stiffness of the tie rods and ears n Vacuum vessels are effectively rigid bodies by comparison 24 -25 Inner Triplet Review - J Kerby 56
LHC Inner Triplet Review @ CERN Hook Design April 24 -25, 2007 T. Page - Fermilab 24 -25 Inner Triplet Review - J Kerby
o Outline o o o Design Overview Analysis Results Component Testing 24 -25 Inner Triplet Review - J Kerby 58
o Hook o o o Design Purpose is to react the axial bellows thrust load on the Q 1 and Q 3 cold masses. Can be installed from one end of the magnet. Current design only reacts loads in one direction n Q 1: force towards the IP n Q 3: force away from the IP Does not work for Q 2 magnets. Proposed variations on design include features to react loads (i. e. vacuum load) in opposite direction. 24 -25 Inner Triplet Review - J Kerby 59
Hook Design The hook wraps around and grabs the fixed point cold mass block. The tie rods are fixed to the end of the vacuum vessel. 24 -25 Inner Triplet Review - J Kerby 60
Hook Design Hook needs to be inserted beyond the cold mass block. 24 -25 Inner Triplet Review - J Kerby 61
Hook Design Hook brought into place on the cold mass block. 24 -25 Inner Triplet Review - J Kerby 62
Hook Design Lower tie bar installed on hook. 24 -25 Inner Triplet Review - J Kerby 63
Hook Design 25 mm nominal gap. 24 -25 Inner Triplet Review - J Kerby 64
Hook Design (4) tie bar design, 15. 875 mm (5/8”) diameter rod, 1/2”thread. (2) tie bar design, 19 mm (3/4”) diameter rod, 5/8” thread. 24 -25 Inner Triplet Review - J Kerby 65
Hook Design 24 -25 Inner Triplet Review - J Kerby 66
o Analysis 24 -25 Inner Triplet Review - J Kerby 67
Hook Deformations Summary Component Vacuum Flange Restraint block @ tie rod connection Deformation (2) Rods Deformation (4) Rods [in] [mm] 0. 008 0. 20 0. 024 0. 60 0. 025 0. 63 24 -25 Inner Triplet Review - J Kerby 68
Hook Stresses - Summary Component Invar Tie rods S. S. Hook (Max. ) Stresses (2) Rods Stresses (4) Rods [psi] [MPa] 22, 300 154 16, 300 112 14, 300 99 21, 500 148 24 -25 Inner Triplet Review - J Kerby 69
Hook Deformations: (2) rods, ANSYS Complete hook system. Vacuum flange only. 24 -25 Inner Triplet Review - J Kerby 70
Hook Deformations: (4) rods, ANSYS Complete hook system. Vacuum flange only. 24 -25 Inner Triplet Review - J Kerby 71
Hook Design - Stresses 24 -25 Inner Triplet Review - J Kerby 72
Hook Design - Stresses 24 -25 Inner Triplet Review - J Kerby 73
o Testing 24 -25 Inner Triplet Review - J Kerby 74
Component Tests – Invar Raw Material Yield strength ~ 337. 7 MPa (48, 970 psi) Ultimate ~ 520. 6 MPa (75, 500 psi) 24 -25 Inner Triplet Review - J Kerby 75
Component Tests – Threaded Connection Linear to ~66, 720 N (15, 000 lb). Load at 20 bar: 33, 350 N (7, 500 lb. ) 24 -25 Inner Triplet Review - J Kerby 76
Component Tests – Single Hook (2) Rods Test load: 88, 964 N (20, 000 lb). 24 -25 Inner Triplet Review - J Kerby 77
Component Tests – Thread Test 2 Tested (4) samples of 1/2 -13 threaded connection. (2) Samples tested to break. (2) Samples cycled 20 times to 5, 000 lb, then to break. One set of this data was missing the break test data. 24 -25 Inner Triplet Review - J Kerby 78
Component Tests – Thread Cycle Data Cycle data as measured. Cycled 20 times to 5, 000 lb. 24 -25 Inner Triplet Review - J Kerby 79
o End 24 -25 Inner Triplet Review - J Kerby 80
- Slides: 80