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FCal1 Production Monitoring and QC. Peter Loch University of Arizona. Quality Control:. large numbers of small, identical parts (tubes, rods): mechanical dimensions checked for ~2% samples (shipment acceptance inspection) ;
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Peter Loch University of Arizona Tucson, Arizona 85721 FCal1 Production Monitoring and QC Peter Loch University of Arizona
Peter Loch University of Arizona Tucson, Arizona 85721 Quality Control: • large numbers of small, identical parts (tubes, rods): • mechanical dimensions checked for ~2% samples (shipment acceptance inspection); • mechanical features (straightness, edges, out-of-roundness) checked for each part individually prior to processing; • individual inspections of all rods and tubes after de-burring, sanding (rods only), drilling (rods only), and cleaning; • final inspection after retrieval from storage, right before insertion; • final acceptance defined by go/no-go at insertion; • absorber, far end and signal plates: • overall dimensions checked for each plate (shipment acceptance inspection); • ~100 electrode and ground pin holes (signal and far end plates only) in each plate checked for dimensions (go/no-go gauges); • individual inspections of all plates and tubes after cleaning;
Peter Loch University of Arizona Tucson, Arizona 85721 Tracing of Small Parts by Batches: • traveler forms are used to trace tubes, rods, etc. during the processing; • information is later merged with logbook entries into electronic database, if applicable; original packaging information cleaning batch number is reference for tube insertion • tags are used to identify cleaning batches through the cleaning procedure; date of QC and bagging is in logbook
Peter Loch University of Arizona Tucson, Arizona 85721 Example: Tracing of Tubes after Insertion: • treatment details of individual tubes can be traced through batch numbers; • all traveler forms, tags, logbooks are archived at Arizona (present model); • information available electronically can be distributed to a central archive at CERN, for example…
Peter Loch University of Arizona Tucson, Arizona 85721 Production Monitoring: • preliminary data collection for production monitoring, with minimum impact on the production itself (no computer input) done by crew as they go; • relevant data is stored electronically in spreadsheets as soon as possible, to allow calculation of trends and status with respect to schedule, for example; • comparison to schedule at least once/week at a local FCal1 production meeting (Tuesdays); results reported to FCal WG at the weekly phone conference (Wednesdays);
Peter Loch University of Arizona Tucson, Arizona 85721 • tube insertion and swaging are traced using MS EXCEL spreadsheets;
Peter Loch University of Arizona Tucson, Arizona 85721 • comparisons to schedule can be done at any time using the same spreadsheets;
Peter Loch University of Arizona Tucson, Arizona 85721 • projections of completion dates are also possible from the same data; scheduled end of process
Peter Loch University of Arizona Tucson, Arizona 85721 Conclusions: • FCal1 quality control methods and documentation are in place for most detector parts; • new methods are developed and the corresponding documentation is added as we go; • process sheets have to be updated to describe the actual procedures (this is in part writing history for processes like tube cleaning, for example); • production monitoring is in place for presently running processes; new monitoring will be added as we go; • major concern: we need to make the essential information on our process organization available on the web (only fragments right now);
Peter Loch University of Arizona Tucson, Arizona 85721 Important: We build a “perfect” detector. This means that all parts in the module, specifically the electrodes, are technically ok after mechanical manipulations. As shorts in the electrodes are the major concern, we test each and every electrode with 600 V at 1 mA trip current immediately after assembly. Electrodes which do not hold this voltage are re-assembled after swabbing the tube, using a new rod. Shipping to CERN generates a hazard to the detector, and we have to re-test all electrodes after arrival. Problematic electrodes will be replaced, so that we maintain the “perfect” detector as long as technically possible.