qxf cable, 1 st generation giorgio ambrosio, paolo ferracin fermilab cern qxf video-meeting june 18,...

QXF Cable, 1st generation

Giorgio Ambrosio, Paolo FerracinFermilab CERN

QXF Video-meeting June 18, 2013

The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404Work supported by the US LHC Accelerator Research Program (LARP) through US Department of Energy contracts DE-AC02-07CH11359, DE-AC02-98CH10886, DE-AC02-05CH11231, and DE-AC02-76SF00515

Outline

• S/LQXF Plan

• Cable R&D goals

• Cable R&D status

• Cable parameters for 1st iteration

• Next stepsJune 18, 2013G. Ambrosio and P. Ferracin 2

SQXF plan and scheduleCoil fabrication

• CERN– Number of coils

• 1 Cu coil• 1 practice + 5 real RRP coils• 1 practice + 5 real PIT coils

– After SQXF01

– Fabrication steps• Winding + curing + reaction +

impregnation– Fabrication time

• ~100 days (5 months) per coil• 1 coil produced every 2 months

• LARP– Number of coils

• 1 practice• 1 mirror + 4 real RRP coils

– Fabrication steps• FNAL: winding + curing• LBNL: reaction + impregnation• BNL: reaction + impregnation

– Fabrication time• ~100 days (5 months) per coil• 1 coil produced every month

09/04/2013G. Ambrosio and P. Ferracin 3

• Sequence: CERN will start with RRP coils– SQXF1 magnet will include the first available four RRP coils produced by the two

“production lines” – With the current plan, either 3 LARP + 1 CERN or 2 LARP + 2 CERN

Slide presented at theLARP-HiLumi Collab Mtg

April 8-10, 2013

SQXF plan and schedule

09/04/2013G. Ambrosio and P. Ferracin 4

Slide presented at theLARP-HiLumi Collab Mtg

April 8-10, 2013

SQXF & LQXF Schedule

09/04/2013 5

2013 | 2014 | 2015 | 2016 | 2017 |

LQXF1LQXF1b

LQXF2

LQXF3 & 3b

SQXF coil in mirror

SQXF1SQXF1b

SQXF2 SQXF2b

Slide presented at LARP Project Reviw

June 11, 2013

S/LQXF Cable plan and schedule• Original plan (Collaboration meeting in Frascati)

– Set cable dimension by 1 March 2013 • 1 year before winding begins

• New deadline (Collaboration meeting in Napa)– June 1, 2013

• 9 months before winding begins– Coil parts fabrication time via standard machining: 6-8 months

• LARP Project Review on June 11, 2013– Cable parameters for 1st iteration decided on June 8, 2013.

• If rapid prototype is used (baseline option)– Coil parts fabrication time: 4-5 months

• Copper wedges take about the same time– So, a second cable iteration in September could be implemented from

the beginning

June 18, 2013G. Ambrosio and P. Ferracin 6

Outline

• S/LQXF Plan

• Cable R&D parameters and goals

• Cable R&D status



Cable Parameters and Goals

• Parameters:– 0.85 mm strands– 40 strands– Stainless steel core (coverage > 60%)

• Goals:– Cabling degradation < 4-5%– RRRafter-cabling > 150

– Is > 3* Iop

– Mechanical stability (no popped strands w/o tools)– No sub-element shearing at cable edges (in micrographs)

June 18, 2013 8G. Ambrosio and P. Ferracin

1042Z- 10

Cable 1042Z 13‐

Sub-element shearing

• Is this a problem?

• 1) Let’s look at “good” magnets– Operating at constant current at > 80% of SSL

• 2) Let’s look at magnets with issues


HQ02a Ramp Rate DependencePreliminary quench data by G. Chlachidze

No quench

170 T/m, 82% SSL at 1.9k, 92% SSL at 4.5K

Strand Damage Score

D.R.DietderichLARP-CERN Meeting May 21, 2013

Damage score for HQ cable996R-B (RRP 54/61)


0 – no sheared sub-element

HQ Cable Damage Score

HQ-012 passcables

HQ-021 passCablesSS-core


Cable in TQS03• Cable 982R

– RRP 108/127– Two pass cabling process– No core– No sheared sub-elements

Note: LQ cable had parameters very similar

to TQ cable

Preliminary observations:

• The best magnets built by LARP have cables with no shearing in subelements The confidence in using Nb3Sn technology for HL-

LHC is mostly based on magnets with this feature Can we have the same confidence if we change the

criteria for cable design?• Are there “good” Nb3Sn coils/magnets which

have consistent shearing in subelements?– I have not found any so far…– Please, show a demonstration if you have it !


Issues in magnets

• Testing Nb3Sn magnets we have seen limiting behaviors, which we cannot completely explain– Reverse ramp-rate dependence

• Many examples …

– Enhanced instability• Ex: LQS02

• What coil yield should we expect during production if we select a cable with shearing planes in each x-section?


Risk analysis

• Based on data collected so far adopting a cable with sheared subelements in each x-section is a risk– ~10 coils needed for understanding impact on coil yield

• First feedback by end of 2014• Full feedback by end of 2015

– Impact on schedule can be significant if we have to change cable design by the end of 2014

– Mitigation plan: develop smaller cable with no sheared subelements, that can fit in same coil x-section

• Smaller strands, 39 strands, … • As demonstrated by HQ02


Outline

• S/LQXF Plan

• Cable R&D goals

• Cable R&D status - LARP



22

Base Line Cable for 0.85 mm Diameter Strand

Preliminary Parameters• 40 Strands• 0.85 mm diameter• w = 18.27 mm • t = 1.50 mm• KS angle = 0.65 deg.

• Tolerance on parameters?

Expand R&D Range• 40 Strands• 0.85 mm diameter• w = 17.75 - 18.27 mm • t = 1.48 - 1.53 mm • KS angle = 0.50 - 0.65 deg.• With/without SS Core• Core widths of

– 8mm (~50%)– 12.7 mm (~80%), Standard– 15.8 mm (~97%)

D.R. DietderichLARP-CERN CM20 April 9, 2013

Ic vs. Cable Section

800

820

840

860

880

900

920

RR

P-1

47

53

B1

04

2Z

-01

-E

S

B1

04

2Z

-10

-E

S

B1

04

2Z

-11

-E

S

B1

04

2Z

-13

-E

S

B1

04

2Z

-13

-E

S

B1

04

1Z

-2-

ES

- An

B1

04

1Z

-9-

ES

-An

Cable Section

Ic (

A)

at

11T

BNL

LBNL

RoundWire

Critical Current of Extracted Strands


RRR vs. Cable Section

0

50

100

150

200

250

300

350

RRP-14753 B1042Z-01-ES

B1042Z-10-ES

B1042Z-11-ES

B1042Z-13-ES

Cable Section

RR

R

BNL

LBNL

RRR of Cables

RoundWire


RRR – Local Variation


05/06/2013Paolo Ferracin 26

Damage Score - QXF 1044Z-6

32/3 + 2/3 = 11.341/4 = 10.25


1044Z-6 117 1.502 18.044 0.542

Damage Score - QXF 1044Z- 7

14/5 = 2.89/3 = 3


1044Z-7 109 1.535 18.055 0.551

1042Z-10

Cable 1042Z 12‐

Damage Score vs. Cable Width for PL of 109 mm

18.47 mm calc. width for 109 mm

Need 17.95 mm width forWinding score of zero

1042Z-13

Cables 1045Z -10,11Comment facet size about the same

April 9, 2013 D.R. DietderichCM20

32

Winding with a Block

• Place block on cable and slide into turn

• Keep block as near to pole as possible while rotating table

• As cable bends around turn strands deform into the shape of the poleAll QXF cables can be

wound w/o popped strands by using this tool

Outline

• S/LQXF Plan

• Cable R&D goals

• Cable R&D status - CERN



Cable R&D

•Width : 17.8 mm•Width compaction Cw = - 3.5•Mid-thickness : 1.50 and 1.53 mm•Keystone angle : 0.65 degree•Pitch length : 113 mm (17.5o) and 125 mm (16o)

Cw larger than its value for the FRESCA2 cable (- 4.6) but smaller than its value for the cable for the dipole DS 11 T (- 2.6).

A. Ballarino Napa, LARP Meeting, 9 April 2013

Cable R&D

PL=113 mm, 1.50 mm

3.9 %(Ic max. 5.8%)

PL=113 mm, 1.53 mm

2.9 %(Ic max. 6.6%)

PL=125 mm, 1.50 mm

2.7 %(Ic max. 4.4%)

PL=125 mm, 1.53 mm

0.52 %(Ic max. 2.4 %)

Mid-thickness

Pitch

4.3 K12 T

4.3 K12 T

4.3 K12 T

4.3 K12 T


Cable R&D

Average Ic degradation = 1.8 %

4.3 K12 T


Cable R&D

T=4.3 KExtracted strands –threeIs > 1000 A

A lot of margin…


Ic (A)

B (T)

What are the results obtained up to now with the most compacted cables having a width of 17.8 mm

The 17.8 mm wide core cables, with and without a core, fabricated with RRP strands are not enough mechanically stable for winding with a keystone angle of 0.65o, a mid-thickness of 1.50 mm and a pitch length of 109 mm or 117 mm.

The critical current degradation is in average around 2 %The RRR values on extracted strands are greater than 130,The stability current at 4.3 K is greater than 1200 A,although there are damage sub-elements in the strands located at the edge of the cable.

Mid-thickness ~ 1.50 mm and PL = 113 mm

Comparison of PIT and RRP core cables (17.8 mm, PF = 109 mm, 1.50 mm)

HE89AHUI109150F

HO90AHUI109150F

No shearing seen through the sub-elements of the PIT cable.

Shearing clearly seen in the RRP strand located at the cable edge.

Susana Izquierdo Bermudez 40

1. CERN winding test set up (2/2)GEOMETRY 1: POLE INNER LAYER

GEOMETRY 2: BIG SPACER INNER LAYER

GEOMETRY 3: POLE OUTER LAYER

Susana Izquierdo Bermudez 41

4. Counter-clockwise (unfavorable) direction

QXFB1042z12, GEOMETRY 1 (POLE INNER LAYER)

H160C123A, GEOMETRY 2 (BIG SPACER INNER LAYER)

42

4. Counter-clockwise (unfavorable) direction

Winding test example (with tool)


Winding test summary


Sample Cable ID Core Strand Width (mm)Mid-thickness

(mm)Pitch length

(mm)

Keystone angle

(degree)

Winding test with

tool

Winding test without

tool1 H16UC0121A NO COPPER 17.800 1.530 113 0.64 not tested OK2 H16UC0121C NO COPPER 17.800 1.500 113 0.64 not tested OK3 H16OC0123A NO RRP 17.800 1.500 113 0.64 not tested NOT OK8 QXF1044z_4 YES RRP (US) 17.950 1.498 0.56 OK NOT OK4 QXFB1042z12 YES RRP (US) 17.944 1.499 96 0.62 not tested NOT OK5 H16OC0123BA YES RRP 17.800 1.551 109 0.66 OK NOT OK6 H16OC0123BB YES RRP 17.800 1.534 109 0.67 OK NOT OK7 H16OC0123BC YES RRP 17.800 1.509 109 0.65 OK NOT OK9 H16EC0131AC YES PIT 17.800 1.506 117 0.65 OK NOT OK

10 H16EC0131AA YES PIT 17.800 1.541 109 0.65 OK OK11 H16EC0131AB YES PIT 17.800 1.523 117 0.65 OK NOT OK12 1045Z-6 YES RRP (US) 18.330 1.520 109 0.55 OK (-) NOT OK13 1045Z-8 YES RRP (US) 18.150 1.520 109 0.55 OK NOT OK14 H16E0132AA YES PIT 18.100 1.525 109 0.57 OK NOT OK15 H16E0132AB YES PIT 18.100 1.540 95 0.55 OK OK16 H16E0132AC YES PIT 18.100 1.520 125 0.57 not tested NOT OK/OK17 H16E0132AD YES PIT 18.100 1.520 117 0.57 not tested OK18 H160C0132CA YES RRP 18.100 1.512 109 0.62 OK NOT OK19 H160C0132CB YES RRP 18.120 1.512 95 0.60 OK NOT OK20 H160C0132CC YES RRP 18.080 1.517 120 0.56 OK NOT OK

Summary - I

• According to preliminary data, it seems that, with cables in the range 17.8-18.3 mm, it is possible to obtain:

– Is > 3* Iop

– RRR> 150– Cabling degradation ~2%


Summary - II

• Sheared (broken) subelements are observed in all the RRP cables so far

• The number of sheared subelements reduces moving from 17.8 to 18.3 mm width– Although it does not disappeared completely at

18.3 mm

• No sheared subelements observed in PIT cables


Summary - III

• Many winding tests performed by LARP and CERN– Width ranging from 17.8 to 18.3 mm

• All cables can be wound with a winding tool

• Without the winding tool, only some PIT cables gave positive results– 1 sample of 17.8 mm– 3 samples of 18.1 mm


1st iteration cable parameters


Dear all, After reviewing the results of the cable R&D collected so far, Dan, Arup, and Luc have agreed to converge on the following parameters for the QXF cable (first iteration). Mid-thickness = 1.525 mm tolerance: +/- 0.010 mm Width = 18.150 mm tolerance: +/- 0.050 mm K.S. angle = 0.55 deg. tolerance: +/- 0.05 deg. The cable R&D will continue in the coming months. In September we plan to review the new data and, depending on the results, confirm or update the parameters (second iteration cable). Paolo and Giorgio

Next steps

• Continue development of cables with 1st iteration parameters– Pitch length and other parameters

• Develop cable for 2nd iteration– Could be implemented in first SQXF coils if rapid-

prototyping will be used

• Plan QXF conductor review around mid of September


qxf cable, 1 st generation giorgio ambrosio, paolo ferracin fermilab cern qxf video-meeting june 18,...

Documents