2. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Report from CERN Auditors Splice Review 23 rd of July 2013 S. Feher on behalf of the CERN Auditors’ team Outline Role of the Auditors Modus Operandi of the Auditors Findings, suggestions and implementations Future Plans

3. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Production Inspections Actor: Operators and supervisors Level: Interconnection Documents: IP for each activity CERN Audit Actor: Team of experienced CERN staff Level: All Documents: IPs, TPs, CERN rules Quality Control Actor: QC team Level: Interconnection, Subsector Documents: TP for each QC activity QA Team Actor: QA team Level: All Documents: IPs, TPs Actions: Review and decision on NCs and border-line cases Follow-up of audits and production quality trends Follow-up and timely completion of test reports and MTF entries Quality Assurance: Organization

4. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 CERN Auditors G. Favre S. Feher P. Galbraith M. Lamont S. Mathot R. Ostojic A. Siemko M. Struik H. Ten Kate D. Tommasini L. Williams

5. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 The role of CERN Auditors  The priorities for SMACC, as defined by the CERN management, are:  Safety  Quality  Schedule  On the basis of the approved SMACC documents and their own experience, the auditors should inspect and audit the manner in which the work is done and the procedures are implemented by the production and QC teams. They should report their findings, with suggestions for improvement of the processes, where applicable.  The auditors should be alert, where necessary take immediate actions, and report to SMACC project leader any event in the tunnel that is at clear odds with the safety of workers and equipment and with CERN rules in general.

6. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Modus Operandi of the Auditors  Visits to the tunnel, during working hours of the SMACC train and QC teams, between 8h-15h.  The QA-support will provide the latest information about the status of activities, keep record of audit planning, and suggest best times for audits.  The audit should be recorded in a report within few days of the visit and returned to the QA- support. The reports will be stored in EDMS (SMACC-QA site).  The QA-support will analyse the audits and report to LSC on the findings.

7. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Auditors’ visits  Visited the tunnel 14 times, in pairs  Mainly inspected sector 56  Observing activities – but not witnessing the entire procedure  Asking questions about why and how the operators do their job  Listening to the operators’ suggestions – tunnel experience  Discussing these visits on Auditors’ meetings  The visits are documented in Auditors’ Reports

8. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations Questioning Procedures:  The bus bars of the spool pieces need to be pulled aside in order to be able to proceed with any of the splice consolidation work. There were no quantitative procedure determining the allowable force applied. Although it is not strongly related it was also observed that some of the spool buses are too lose and it is hard to install the insulation box. Extensive discussions: Bus could not be pulled out from the spacer block Checked by endoscopy the soundness of the bus bars US weld joint could be in danger? No, each spool bus weld joint can handle 150 kg Conclusions: Does not appear that damage has been done Careful handling by hand (no tools): not to apply any significant force

9. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations Questioning Procedures cont’d:  The ELQA Operators could set on the spot the HV stand off test Voltage and leakage current values.  They should strictly follow procedures.  If threshold values need to be changed MP3 needs to be involved.  The high voltage PSs can go up to 3kV and have no hardware limit. There are pre programmed scripts that run the HV ramp.  Strong recommendation is to include a hardware limit switch if it is possible so there is no easy way to change the setting neither easy to accidently run an undesired script.

10. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations Tooling:  The tooling during splice machining is not always turning in the favourable direction (upmilling or downmilling). Does this affect the surface quality? Eye exam: there are definite differences on the different sides of the machined surfaces, however the surface quality by QC is OK. There is a preferred milling direction. Conclusion: Re-examine the procedure. Perform bench tests. Apply different procedure or modify the tool to be able to change rotational direction.

11. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations Safety: There is a potential problem with the soldering machines that can be started prematurely before the control thermocouple is plugged in. (Could it be permanently mounted?) Safety switch is being introduced to avoid accidental turn on the equipment.

12. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations Safety cont’d: Hot swarf punching holes on the protection plastic - Fire hazard The material properties of the protection sheet has to be checked to ensure that nonflammable material is used.

13. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations House keeping:  The milling machine is used for removing the insulation. Also for labelling reasons tape was placed on the surface area reserved for solder joints. Is the cleaning with alcohol and Scotch Brite effective enough and how often are the pads changed? Should the freshly machined splices be temporarily protected with (household) aluminium foil?  After machining is done there are only few days before the shunt installation takes place. The procedure calls for surface preparation with Scotch Brite (to remove oxide layer) and alcohol. There were no requirements how often the Scotch Brite is replaced with new ones.  New Policy: for every different interconnect new Scotch Brite will be used. Introducing the Aluminium foil would significantly complicate the work flow and the benefits by using it is not substantial.  Dust found inside the interconnects should be analysed for metal contents. Oil drop found on the inner surface of the cryostat wall.  Keep cleanliness as a high priority.  We found unmarked rolls of solder in the tunnel, what is done to prevent this? Better labelling?  Labelling as a general practice is highly recommended, however only one type of solder is used by a production team even if the solder for the splice installation team is different than the solder for the shunt installation team.

14. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Future Plans  Every activities need to be visited few times and examined the procedures systematically not just picking parts of the procedures randomly.  As we go further it is expected that the number of new NCRs will be reduced. This does not mean that the importance of auditing will be reduce. In the contrary: Routine and self confidence will kick in. More reluctance to follow procedures. The procedure will not be reviewed by the operators frequently. Auditors’ visits will be very important.

16. Splice Review: Report from CERN Auditors, S. Feher, 23 July. 2013 Findings, suggestions and implementations Questioning Procedures cont’d:  Why are the available Ultem protection boxes not always in place during soldering?: for better accessibility? No clear answer.  Why are Ultem boxes being modified to fit in the tunnel if we have 1000 units ready machined: no answer.  Who verifies the kapton insulation before installing the insulation box?: LMF: the same person who does the insulation also installs the insulation box..  Cutting and welding flanges will shrink them by a few mm, is this acceptable?: according to Cedric yes.  During M-line cutting swarf gets hot enough to burn through the sheets supposed to contain them?: no answer yet.