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Cleanness of the 3-4 cold beam lines. C. Garion on behalf of TE/VSC with materials of Vincent Baglin. Outline: History: Status of 2009 cleaning Foreseen and additional activities on cold beam lines. Inspection and cleaning activities in sector 3-4 during LS1 Activity sequence Procedure
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Cleanness of the 3-4 cold beam lines C. Garion on behalf of TE/VSC with materials of Vincent Baglin C. Garion Outline: • History: Status of 2009 cleaning • Foreseen and additional activities on cold beam lines. • Inspection and cleaning activities in sector 3-4 during LS1 • Activity sequence • Procedure • Schedule • Conclusion
History: Beam vacuum line cleanness in sector 3-4 after incident • Contamination types: • MLI • Soot • (Debris) LSS4 LSS3 Soot MLI Contamination distribution: C. Garion
History: Cleaningmethodsafter 3-4 incident (1) • Foam plugs for the soot: • Use of two plugs for horizontal and vertical parts of the beamscreen • Use of alcohol-wetted and dry foam plugs • Up to 50 passages in each direction withwetfoam plug and up to 15 passages with dry plug Example of C19R3.V2 C. Garion
History: Cleaningmethodsafter 3-4 incident (2) • Air flux for the MLI: • 1st step: automaticpumping/venting • A cycle : 20 s pumping, 18 s plateau, 2 second vent • The pressure is reduced from 1 atm to 0.8 atm in 2 s • (to be compared to the arc pump down of 200 mbar/h) • Apply this process for 30 min (40 pumping/venting cycles) • 2ndstep: aspiration with local pertubationcontrolled by endoscope • nozzleblowsfiltered air, the MLI residuesleftbehind the beamscreen and the RF fingers are directedtowards the beam aperture wherethey are aspiredaway. • Time : 5 min per PIM, speed of 3 m/min along the beamscreen C. Garion
History: cleannessafter 3-4 incident • Acceptance criteria: • After discussion with AB-ABP and following Chamonix it was agreed with the management that : • 1 fibre per half-cell • 2 debris (MLI or other less than 1 mm2) per magnet • can be left in the beam tube after the cleaning process ! • Few pictures of non-conformities: A32L4 V1 Q34R3 V1 Q29L4 V1 C. Garion
Foreseen activities on cold beam lines (at the LS1 start). 4 Magnet exchanges Point 3 Point 4 Damaged bellows (PIM cutting to be confirmed at opening: not to be changed) «standard» endoscopy (54 m in one direction per line) C. Garion
Foreseen and additional activities on cold beam lines. • 2 additional openings are asked for inspection and investigation (Endoscopy). • Extended endoscopies. • Air flux for MLI removal • New opening: • QBBI.A14R3 (V2); • QBBI.A20R3 (V2) Point 3 Point 4 C. Garion
Inspections and cleaning activities in sector 3-4 during LS1 (1) Sequence: Prudent endoscopy* analysis Cleaning by pulsed air flow Endoscopy Cleaning by pulsed air flow Point 3 Point 4 Cleaning by pulsed air flow (24h) toward point 4 Analysis and decision * Prudent endoscopy: if too many debris are observed, the endoscopy will be stopped and the cleaning carried out endoscopy. C. Garion
Inspections and cleaning activities in sector 3-4 during LS1 (2) Sameprocedure as in 2009 willbeapplied (EDMS 989454) Samematerial, available C. Garion
Schedule of inspection and cleaning activities in 3-4 • All interconnections and beam vacuum lines related to these activities in sector 3-4 are opened including the QBBI.A14R3 and QBBI.A20R3 • VSC activities in parallel with SIT reconnection work. No closure of the beam vacuum lines (PIM installation before the end of the activity) • Start of VSC activities beginning of August (8 August) • ~ 3 weeks in total • From point 4 first (to avoid interaction with optical fibre activity, t.b.c.); • Mid august from point 3 C. Garion
Conclusion A scenario of inspection and cleaning of the cold vacuum beamlines in sector 3-4 isproposed. The additionalwork for the SMACC team has been minimizedwhileprovidinga maximum of informations and efficiency of the cleaning. A cleaning of the 2 beam vacuum lineswillbecarried out based on pulsed air flow. Procedure and tooling have already been applied in 2009. C. Garion
Back up slides Cleannessafter incident PIM status Interconnectionstatus C. Garion
UFO activity To beinspected, mostlikely a consequence of 3-4 incident Source probablyidentified - ongoing Inspected and no cause found Courtesy of T. Baer C. Garion
Beam screens with soot in tunnel : B19R3 B19R3.V2 before cleanning After cleanning end entrance mid V. Baglin Chamonix 2009
Beam screens with soot in tunnel : C19R3 C19R3.V2 before cleanning After cleanning end entrance mid V. Baglin Chamonix 2009
RF ball test RF ball after test of V1 in sector 3-4: Few MLI chips found C. Garion