NCSX R&D Activity Update Jim Chrzanowski June 11, 2003

New Casting- Measure Tolerance Build Includes a number of worse cast conditions of modular coil Fits in R&D Test Oven

Drawing of New Casting

Update- CTD Epoxy Test Results Compression Tests- Single conductor –Compressive strength at all temperatures show low variability with low coefficients of variation

Compressive Strength Results Compressive 100K 43.5 to 47.9 ksi Compressive 150K 39.2 to 40.8 ksi

Compressive Strength Results Compressive 295K 25.2 to 27.5 ksi Compressive 76K 45.2 to 49.1 ksi

Types of Failure- Compressive Tests Insulation Unwraps Insulation Split

Keystone Trials Bench top tests to compare single vs. 4- conductor –Wind conductors in both directions –Butt lapped vs. half lapped insulation –Can reforming be successful –Sufficient insulation coverage with Butt lap?

Test Setup Insulated conductors were wound on 3 inch diameter pipe

Test Preparations

Conductor samples were cut 36 inches in length One end of 4-conductor sample was soldered 4-conductor insulation –1 butt lapped glass 3-butt lapped co-wound glass/Kapton Single conductor insulation (Comparison tests) –1 butt lapped layer glass & 3-butt lapped layers co- wound glass/Kapton –1 half-lapped layer glass and 2 half-lapped layers of co- wound glass/Kapton

4-Rope Conductor- Results of Bench Top Tests A B C D Height C Width A Height D Width B Width A0.739 Width B0.745 Prior to Winding Height C0.586 Height D0.613 B A D C After Winding After Forming Length of inner turns grew by 5 inches

Width B0.609 Height D0.706 Prior to Winding Height C Width A A B C D Single Conductor- Results of Bench Top Tests B A D C After Winding Half-lapped Width B Height D Height C0.733 Width A Butt-lappedHalf-lappedButt-lapped

Preliminary Findings Not obvious that there is significant gain with keystoning comparing half vs. butt insulation Questionable Kapton insulation coverage using Butt lapped Taping has to be performed in two passes –Space of conductor supports causes excessive movement of conductor during taping. Evaluation of reforming not complete