US LHC Accelerator Research Program bnl fnal lbnl
US LHC Accelerator Research Program bnl - fnal- lbnl - slac Cable Fabrication Plans and Experience D. R. Dietderich Lawrence Berkeley National Laboratory May 9, 2012 D. R. Dietderich, LARP CM-18
Outline of the Presentation • Cable inventory for HQ/LHQ and plans • Cable R&D – 140 mm to 150 mm bore – Cable fabrication of 217 stack • R&D to reduce HQ cable dimensions – Wire diameters 0. 778 mm and 0. 80 mm • Cored cable R&D May 9, 2012 D. R. Dietderich, LARP CM-18
HQ/LHQ Cable Parameters & Processing • Nominal Parameters – – – Annealed wire 185 -190 C for 4 hours Wire diameter: 0. 778 mm Thickness: 1. 375 mm Width: 14. 8 mm Keystone Angle – 0. 75 deg. • Stainless steel core, biased towards thick edge – Tape composition - 316 L stainless steel – 8 mm wide – 0. 025 mm thick May 9, 2012 D. R. Dietderich, LARP CM-18
HQ/LHQ Cable Status • Cable available for coil winding – “Z” will denote a cable with a core. – 1020 Z-D • 1 UL insulated – 1021 Z – A 1, A 2, B (4 UL) • 1 UL insulated braided on by NEW • Insulation layer thickness 0. 104 mm – Nearly the same thickness as prototype run with 0. 103 mm. • Used in HQ coil 17 • 3 UL insulated with sleeve from Rev. Comp. – 1021 Z-C – R&D 1 UL NOT insulated, PL ~85 mm • 1024 Z – 5 UL fabricated, • • 1 UL 1 insulated 4 UL-HQ (400 m) not insulated (Save for HQ for LHQ) Ti doped Used HQ coil 18 • 1025 Z – 1 UL (300 m) LHQ practice cable • Ready to insulate at NEW May 9, 2012 D. R. Dietderich, LARP CM-18
Next LHQ/HQ Cable Run • May to August – LHQ cable, fabricate 2 UL (May) • Standard HQ/LHQ cable with core – HQ cable with RRP 217 stack, 1+ UL (June) • Standard HQ/LHQ cable with core – MQXF Cable for 140 -150 mm bore (July. August) • R&D run to define cable parameters • 40 strands • Wire diameter ~0. 85 mm May 9, 2012 D. R. Dietderich, LARP CM-18
Cable for 140 -150 mm Bore May 9, 2012 D. R. Dietderich, LARP CM-18
Possible Cable Parameters for 140 mm • • If wire diameter is 0. 85 mm the cable: Width: ~18. 25 mm Thickness: ~1. 50 mm Keystone angle: ~0. 65 deg. May 9, 2012 D. R. Dietderich, LARP CM-18
Cored Cable 1012 Used in HQ Coil 12 • HQ cable 1012 (old cable parameters) – 35 strands with diameter of 0. 80 mm – 1. 44 mm mid-thickness, • Did not increase mid-thickness with core addition – 15. 1 mm wide – 0. 75 deg. Keystone angle – 8 mm wide, 0. 025 mm thick stainless steel core • Biased to thick edge of cable – Core biased toward thick edge of the cable • No fabrication issue with the addition of a SS core • Addition of the core did not degrade the Ic – Measurements show a reduction of ~3% which is typical for this cable without a core May 9, 2012 D. R. Dietderich, LARP CM-18 Mandrel with slot for adding a core
Objective of Cable R&D • To use existing HQ tooling cable dimensions needed to be reduced to: – Provide more space azimuthally (i. e. thinner cable) – Provide more radial space (i. e. narrower cable) • Cable R&D targets dimensions: – Reduce HQ cable thickness by 65 -100 microns • To 1. 375 mm - 1. 340 mm – Width target is < 15 mm (14. 7 mm -15 mm) • Accommodates dimensional changes of cable during reaction • Thicker insulation or more insulation between layers and tooling – Keystone angle un-changed at 0. 75 deg. May 9, 2012 D. R. Dietderich, LARP CM-18
HQ Cable Parameters of R&D Cables HQ Box New HQ cable Zone with Too much damage May 9, 2012 TQ LQ D. R. Dietderich, LARP CM-18
Critical Current Cable 1014 with 0. 80 mm Un-deformed Round Wire Extracted Strands May 9, 2012 D. R. Dietderich, LARP CM-18
RRR 1014 – 0. 80 mm wire Un-deformed Round Wire May 9, 2012 D. R. Dietderich, LARP CM-18
Critical Current Cable 1015 – 0. 778 mm wire 1 st Production cable 1017 Un-deformed Round Wire Extracted strands May 9, 2012 D. R. Dietderich, LARP CM-18
Cable 1015 Sections I & L 1015 -I • No significant subelement damage is observed in the wire cross-sectional images May 9, 2012 D. R. Dietderich, LARP CM-18
Summary • HQ and LHQ cabling process established • Target cable parameters for MQXF presented • The critical current variation can be due to: – Sample handling while preparing for Jc testing? – Or localized damage in some strands during cabling? – Suggests that a cable testing facility is needed for accurate cable critical current measurements. • A stainless steel core can be added to the standard HQ cable without significant loss of critical current May 9, 2012 D. R. Dietderich, LARP CM-18
Extra slides May 9, 2012 D. R. Dietderich, LARP CM-18
1 Pass Cable with Stainless Steel Core May 9, 2012 D. R. Dietderich, LARP CM-18
LARP Cable Fabrication • 2 pass process was developed to reduce dimensional changes of a cable during coil processing and reaction – A cable is fabricated oversize in thickness, annealed (200 C for 2 -4 hrs), and re-rolling to final thickness. • Very important -- Cable is permitted to get wider during the second pass • The anneal reduces the residual stress in the cable and the cable shortens by 0. 20 – 0. 25%. • 1 pass process has been developed for adding stainless steel (SS) cores to cables – Strand is annealed (190 C for 4 hrs) prior to cabling – Cable is made to final dimensions • Due to the mechanical differences between the strand the SS core a 2 pass process is not possible. • However, other core materials such as S-glass tape or Mg. O paper tapre with a SS core May 9, 2012 D. R. Dietderich, LARP CM-18
Cable R&D to Reduce Cable Size • The next slide shows the thickness and width of several cable samples – Cable 1014 • 34 strands with a diameter of 0. 80 mm – Cable 1015 • 35 strands with a diameter of 0. 778 mm • “Blue Box” denotes the target parameters needed to accommodate the cable dimensional changes in the present tooling. – Dash line are the deduced parameters from R&D on TQ and LQ coils • “Red Circle” denotes the new HQ parameters with the 0. 778 mm diameter strand May 9, 2012 D. R. Dietderich, LARP CM-18
R&D to Reduce HQ Cable Dimensions • New cable parameters: – Mid-thickness – Width – Keystone angle 1. 375 mm 14. 80 mm 0. 75 deg. from 1. 44 mm from 15. 10 mm Unchanged • New cable designs will provide more space in tool for cable dimensional changes – Have made the first production cable 1017 with new parameters • HQ coil 14 has been fabricated and is ready to test in a mirror. – Have just made a cored cable with the new cable parameters with a strand diameter of 0. 778 mm. • Coil winding with the cored cable was OK – However, popped strands were produced going around the pole • They are pushed back into position as winding continues – Planning to cut HQ coil 12 into sections for inspection. May 9, 2012 D. R. Dietderich, LARP CM-18
- Slides: 20