Failure Mode CPA Surface Finish Problem QA Design

Failure Mode: CPA

Surface Finish Problem QA (Design) QC (Production) CPA edge tube surface scratches Shipping/handling procedures Visual inspection HV test HV cup surface scratches Shipping/handling procedures Visual inspection HV test Discharge along CPA hanger Design and prototype test HV test 2

Electrical Interconnect Thermal Cycle / After a Spark Problem QA (Design) QC (Production) Connection between HV cup and HV bus Design and prototype test Resistance check thermal cycle HV bus connection between modules Design and prototype test Resistance check thermal cycle HV bus connection to the CPA corners Design and prototype test Resistance check thermal cycle Connection between tube Design and prototype test ends and the resistive tube Resistance check thermal cycle Resistor connection between main sheets and field shaping strips Design and prototype test Resistance check thermal cycle Interconnect between neighboring resistive sheets Design and prototype test Resistance check thermal cycle 3

Mechanical Problems Problem QA (Design) QC (Production) Bad rounding radii on mating parts Design and prototype test Visual inspection Fasteners come loose after Design and prototype test thermal cycling Thermal cycle Warping of structure after thermal cycling Design and prototype test Thermal cycle Delamination of resistive film after thermal cycling Design and prototype test Thermal cycle Uneven gap between modules in LAr Design and prototype test Specification 4