HQ Coil 23 and 25 Status

LARP Video MeetingSeptember 19, 2013

Dan Cheng

HQ Coil 23 Status

• HQ Coil 14 has been examined – Seemed to have similar epoxy fill issues between

polyimide trace layers as Coil 23 did– Coil was sectioned earlier– Traces were peeled back to examine epoxy fill of coil

• Coil 23 “Spot” has been cut away and examined– Does not affect the integrity of the coil in any way

• Instrumentation & QA on hold still, depending on decision on coil

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 2

Coil 23, Post-impregnation

Outer layer, RE Outer layer, straight section

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 3

Coil 23, Post-impregnation

Inner layer, RE Inner layer, LE

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 4

Outer Layer Comparisons

Coil 14 OL, Lead end Coil 23 OL, Lead end

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 5

Coil 14 Deconstruction

Coil 14 IL, RE, post-impreg. Coil 14 IL, RE, trace peeled off

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 6

Despite no fill between polyimide, coil shows complete fill

Kapton layer separated from trace

Coil 14 Deconstruction

Coil 14 OL, end of ramp area, post-impregnation, sectioned

Coil 14 OL, end of ramp area, trace peeled off

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 7

Coil 23 Inner Layer Check

Inner layer, Pole gapInner layer, pole gap,Spot cut away

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 8

Trace polyimide, with VHB backingKapton layer, conforming

to epoxy in pocket

Coil 23 Summary of Findings

Based on examination of Coils 14 & 23 Coil 23 IL, Return end

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 9

• White areas (shown, right) are likely surface conditions only – Is not an indicator of quality of fill

in the coil

• Coil fill is likely solid underneath the trace– Even where polyimide separated

from Kapton layer– Coil structures are likely fully

supported by epoxy composite

• If this coil passes electrical checks, this coil could be considered a usable coil

HQ Coil 25 Status

• Impregnation preparations will incorporate– Purchasing new CTD 101K epoxy kit (2-3 wk lead)– Revising our trace preparation procedures to improve

quality of fill between layers– Revising our lead splice procedures (based on input

from 8/22 QXF Coil WG meeting)• Impregnation preparations can start without

waiting for the changes mentioned above to be completed– But will have to be planned around HQ Coil 26 winding,

etc. operationsSept 19, 2013D. Cheng - HQ Coil 23, 25 Status 10

• Extra slides

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 11

Coil 14 Trace Preparations

Coil 14 IL trace laminate

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 12

Film of cleaner (alcohol or acetone?) between layers

CMM Data, At 26” (660mm) Location

Sept 19, 2013D. Cheng - HQ Coil 23, 25 Status 13

Coil 23 Coil 20, for reference

+250 µm~ 0.010”