CERNCH-1211 Geneva 23Switzerland

LHC

CERNCH-1211 Geneva 23Switzerland EDMS NO. REV. VALIDITY

1995583 0.3 DRAFTREFERENCE

LHC-LE-EC-0005

Date: 2018-11-30

ENGINEERING CHANGE REQUESTInstallation of the Connection Cryostat Full

Assembly in the LHC P2 (HL-LHC WP11)BRIEF DESCRIPTION OF THE PROPOSED CHANGE(S):

It is foreseen to substitute in the DS region at point 2 two ~12 m long connection cryostats each with a cryo-assembly composed by a pair of 5.3 m-long cryostats with in the middle a 2.2m long bypass cryostat in which is hosted the TCLD collimator. Thanks to this change the luminosity foreseen for the ion collision after LS2, following the ALICE upgrade, can be reached without surpassing the quench limit of the MB and MQ superconducting circuits.

DOCUMENT PREPARED BY: DOCUMENT TO BE CHECKED BY: DOCUMENT TO BE APPROVED BY:D. Schoerling et al. HiLumi-WP11-Integration

C. Adorisio, G. Arduini, V. Baglin, M. Barberan, I. Bejar Alonso, N. Bellegarde, M. Bernardini,

C. Bertone, C. Boccard, L. Bottura, G. Bregliozzi, M. Brugger, J.P. Burnet, S. Bustamante, S. Chemli,

F. Cerutti, P. Chiggiato, J. P. Corso, D. Delikaris, B. Delille, R. Denz, A. Devred, R. de Maria, S. Evrard, P. Fessia, R. Folch, A. Foussat,J.- F. Fuchs, C. Gaignant, M. Giovannozzi,

G. Girardot, J.-L. Grenard, M. Lamont, S. Le Naour, M. Martino, D. Missiaen, M. Modena,

V. Montabonnet, Y. Muttoni, M. Nonis, T. Otto, E. Page, S. Redaelli, D. Ricci, I. Romera Ramirez,

B. Salvant, F. Savary, J. Sestak, A. Siemko, R. Steerenberg, L. Tavian, M. Tavlet, C. Vollinger,

J. Wenninger, M. Zerlauth, A. Lechner, C. Bahamonde Castro, C. Zamantzas.

P. Collier(on behalf of LMC)

L. Rossi(on behalf of the HL-LHC

project)

DOCUMENT SENT FOR INFORMATION TO:ATS Group Leaders

SUMMARY OF THE ACTIONS TO BE UNDERTAKEN:Following drawings and documents need to be updated, once the change is being performed:-Survey reference drawings to be created (D. Missiaen)-LHCLSQR_0022 and LHCLSQR_0023 (R. van Weelderen)-LHCLSVI_0020 and LHCLSVI_0026 (P. Cruikshank)-LHCQQ_IG0033, LHCQQ_IG0049, LHCQQ_IG0050 and LHC-LI-ES-0017 (JP. Tock)-LHC-LE-ES-0001 and LHC-LE-ES-0002 (D. Duarte)-LHCLSSH_0003 and LHCLSSH_0004 (M. Amparo Gonzalez De La Aleja Cabana)

Note: When approved, an Engineering Change Request becomes an Engineering Change Order. This document is uncontrolled when printed. Check the EDMS to verify that this is the correct version before use.

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1. INTRODUCTIONThis ECR describes all necessary actions and required changes for the substitution of two ~12 m long connection cryostats each with a cryo-assembly composed by a pair of 5.3 m-long cryostats with in the middle a 2.2m long bypass cryostat in which is hosted the Target Collimator Long Dispersion suppressor (TCLD) [1], where the latter is treated in a separate ECR by WP5 [2]. This upgrade must take place in LS2 in order to allow full heavy-ion luminosity in Run3 and exploitation of the ALICE experiment (in LHC P2) that will be upgraded during LS2.The present state of the areas is shown in Figures 1 and 2.

Figure 1 — Laser scan of area under change, R22 – present LEBR.11L2 (July 2017)

Figure 2 — Laser scan of area under change, R28 – present LECL.11R2 (July 2017)

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2. REASON FOR THE CHANGEThe ~12 m long connection cryostats will be replaced each with a cryo-assembly composed by a pair of 5.3 m-long cryostats with in the middle a 2.2m long bypass cryostat in which is hosted the Target Collimator Long Dispersion suppressor (TCLD). This change is necessary to make possible the installation of the TCLD collimator. The reason for installing the TCLD is described in detail in [2] and [3].

3. DESCRIPTIONIt is foreseen to exchange the following two cryostats: LEBR.11L2 LECL.11R2These cryostats are installed at the following positions: LEBR.11L2: distance from IP2: -432.1047 m, distance from IP1 (DCUM):

2900.2557 m LECL.11R2: distance from IP2: 419.33 m, distance from IP1 (DCUM): 3751.6904m

In detail, the changes comprise the following:P2 left side

Removal of the present cryostat LEBR.11L2. Installation of the connection cryostat full assembly at the LEBR place. The

assembly is composed of two new connection cryostats (shorter in length), with a bypass cryostat installed between them.

After that, installation of a new TCLD collimator between the two connection cryostats, on the beam line 2, B2I (internal beam, passage side) will follow.

P2 right side Removal of the present cryostat LECL.11R2. Installation of the Connection Cryostat full assembly at the LECL place. After that, installation of a new TCLD collimator between the two connection

cryostats, on the beam line 1, B1I (internal beam, passage side) will follow.Layout drawings LHCLSS__0019/LHCLSS__0020 (LHC layout for the DS region at point 2) and LHCLSSH_0003/LHCLSSH_0004 (HL-LHC layout for the same zones) show the changes induced by the implementation of the TCLD collimator and the two connection cryostats where there was one ~12m long connection cryostat. Figures 3 and Figure 4 show as an example the section of the LHC layout for P2 left before and after the change.The components to be installed (Table 1), to be kept (Table 2), to be displaced (Table 3) or to be removed (Table 4) are listed below.

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Figure 3 — Section of LHC layout for P2 left (from LHCLSS__000019).

Figure 4 — Section of HL-LHC layout for P2 left (from LHCLSSH_0003) – New components.

Table 1 — Components to be installed [4]Equipment name DCUM IP2 Comments

LEPRBLENRALEPRA – CC Full assembly L2

2900.2557 m2905.56505 m2907.72105 m

– 432.1047 m– 426.79535 m– 424.63935 m

Composed of 2 cryostats + 1 bypass cryostat.

New 6U crate - - To be installed under MB.10L2. See 2.4.5 in [4]

LEPLALENLALEPLB – CC Full assembly R2

3751.6904 m3756.99975 m3759.15575 m

419.33 m424.63935 m426.79535 m

Composed of 2 cryostats + 1 bypass cryostat.

New 6U crate - - To be installed under MB.10R2. See 2.4.5 in [4]

Table 2— Components to be kept [4]Equipment name DCUM IP2 Comments

- - -

Table 3— Components to be displaced [4]

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Equipment name DCUM IP2 CommentsBLMEL.11L2.B2I20_LEBR 2907.01 m - BLMEL.G11L2, old DCUM givenBLMEI.11L2.B2I20_LEBR 2907.36 m BLMEI.H11L2, old DCUM given

BLMEL.11R2.B1I20_LECL 3757.01 m - BLMEL.H11R2 , old DCUM givenBLMEI.11R2.B1I20_LECL 3757.36 m BLMEI.I11R2, old DCUM given

Table 4 — Components to be removed [4]Equipment name DCUM IP2 Comments

LEBR.11L2 2900.2557 m – 432.1047 m

LECL.11R2 3751.6904 m 419.33 m

3.1 INTEGRATIONThe integration is described in detail in the document [4].

3.2 VACUUM MODIFICATIONSIn order to provide beam vacuum continuity of the Connection Cryostat Full Assembly, the continuous beam line of the replaced cryostat must be segmented and adapted to accommodate the functioning of the TCLD collimator and the connection cryostats. The installation of the TCLD collimator, operating at room temperature, imposes a new sectorization of the vacuum lines and new transitions between cold and warm vacuum lines. The improved pumping strategy for these new vacuum sectors is proposed in [5]. All changes of the vacuum layout are defined in [6]. The cost sharing between the workpackages is described in [7].Inside the 5.3 m long cryostats (LEP type) the standard LHC-type beam screens will be installed for both beam lines (cold bore inner diameter 50mm). Regarding the bypass cryostat (LEN type) there are two different configurations, one for each beam line, depending if it is the collimated or the non-collimated line. For the collimated line, there will be one bellow to ease its mounting/dismounting and one sector valve (RF all-metal gate valves, ID 63) installed on each side of the TCLD. The sector valves are then connected to the cold-warm transitions (short and long versions, located upstream and downstream respectively) and followed by the standard Plug-in-Module (PIM). The collimator itself will represent an added vacuum sector, described in detail in [6]. A vacuum port is integrated in the cold/warm transition, between the sector valves and the continuous cryostat, to allow the RF ball tests. For the non-collimated line, a new concept of conduction cooled copper cold bore has been developed to reduce the equipment needed on this line of the bypass cryostat. It will be thermalized at both extremities by two hoses routed from the M line, feeding superfluid helium at 1.3 bar to the collars brazed around the line. The copper cold line is linked to the PIMs at the extremities. A standard LHC-type beam screen is inserted in the cold line. To accommodate all the described equipment within the existing space, special short beam screen bellows had to be designed and manufactured.The insulation vacuum continuity is ensured by the LEN cryostat.

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3.3 CRYOGENICS MODIFICATIONSThe bypass cryostat replacing the connection cryostat in machine cell 1011 causes a significant increase of the longitudinal hydraulic impedance in the insulation vacuum-space compared to today’s installation. In case of a 30 kg/s cold helium flow from the cold mass into the insulation vacuum space, as identified as Maximum Credible Incident (MCI) in [8], a sufficient number of safety valves are installed to limit the cryostat pressure to 1.5 bar. The present scheme, implemented after the incident of 19th September 2008 and revised in LS1 is summarized in [9, 10]. An investigation whether this MCI-discharge flow occurring on one side of the cryogenic bypass can be at least partly shared with the other side, without introducing an excessive pressure drop, showed that such sharing is insufficient [11]. Therefore, each side of the cryogenic bypass is to be considered as an individual hydraulic sector with respect to MCIs and it must be possible for the full flow to be discharged by safety valves on either side of the bypass.In addition, to avoid multiple helium clouds in case of an incident when personnel access is allowed in the tunnel (during low current powering, so-called “phase I” [9]), one SV per vacuum subsector opens at a low pressure (so-called unsprung SV), allowing evacuation of up to 1 kg/s of helium via a single port. The additional hydraulic impedance of the bypass cryostat increases the maximum internal pressure for such a 1 kg/s discharge. An investigation whether this MCI-discharge flow occurring in the dispersion suppressor cryostat equipped with bypass cryostat showed that the internal pressure slightly exceeds the 80 mbar opening pressure of the sprung loaded DN200 SV in the hydraulic sector opposite to the location of the unsprung SV [11]. A simple solution to increase the opening pressure of the DN200 SV by applying a second spring has been verified [12]. Furthermore, the two DN90 SV with opening pressure of 67 mbar shall be removed from the vacuum subsector. The insulation vacuum protection scheme at LHC IR 2 DS vacuum sector before and after LS2 is summarized in Tables 5-8. The change concerns removal of the DN90 SV at Q7 and Q9, and equipping the by-pass cryostat (LEN) with several DN200 SV, where all SV between Q11 and LEN have double springs. The SV position without spring remains unchanged in cell 10.Additional cryogenic instrumentation will be implemented during LS2. A total of seven temperatures sensors (CERNOX) and two flowmeters (Coriolis) will be installed at P2 right side after having installed the connection cryostat [13]. No additional instrumentation at P2 left side will be installed. This choice was taken because the beam screen heat load on the right side is larger. Figure 5 shows the instrumentation in this half-cell. Figure 5 shows the instrumentation in this half-cell.

Table 5: LHC IR2 LEFT Insulation vacuum protection scheme as installed on 31st of January 2019Q11

LE MB

MB

Q10

MB

MB

Q9 MB

MB

Q8 MB

MB

Q7 DFBA

DN230DN200* 1DN200 1 1 2 1 2 1 2 1

DN200**DN160DN100DN90 1 1

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D65Limited stay

*no spring loading, **double spring loadedTable 6: LHC IR2 LEFT Insulation vacuum protection scheme after installation of the connection

cryostatQ11 LEP LEN LEP M

BMB

Q10 MB

MB

Q9 MB

MB

Q8

MB

MB

Q7 DFBA

DN230DN200* 1DN200 1 1 2 1 2 1 2 1

DN200** 5DN160DN100DN90D65

Limited stay*no spring loading, **double spring loaded

Table 7: LHC IR2 RIGHT Insulation vacuum protection scheme as installed on 31st of January 2019

DFBA

Q7 MB

MB

Q8 MB

MB

Q9

MB

MB

Q10 MB

MB

LE Q11

DN230DN200* 1DN200 2 1 2 1 2 1 1 1

DN200**DN160DN100DN90 1 1D65

Limited stay*no spring loading, **double spring loaded

Table 8: LHC IR2 RIGHT Insulation vacuum protection scheme after installation of the connection cryostat

DFBA

Q7 MB

MB

Q8 MB

MB

Q9

MB

MB

Q10 MB

MB

LEP LEN LEP

Q11

DN230DN200* 1DN200 2 1 2 1 2 1 1 1

DN200** 5DN160DN100DN90D65

Limited stay*no spring loading, **double spring loaded

Figure 5 – InstrumentationAdditional instrumentation for the connection cryostat, P2 right side (half-cell 11R2_947) [1113].

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3.4 GEOMETRY AND ALIGNMENT MODIFICATIONSThe installation of the connection cryostat full assembly requires the alignment of two cryostats, the bypass cryostat and the TCLD collimator compared to previously only one connection cryostat. In detail, the following operations have to be performed:

1. The marking on the floor of the beam points, jacks heads position of the non-standard connection cryostats but also the beam points and component axis of the bypass cryostat and of the new TCLD collimator is required. A specific care will be brought to the jack configuration of the dipoles, as not standard.

2. 12 jacks per Connection Cryostat Full Assembly will be installed. 3. EN-SMM-ASG will align the jacks’ heads at their nominal position, prior to the

installation of any component. 4. The connection cryostats will be installed 5. An initial alignment of the connection cryostats will be carried out with respect to

the adjacent cryo-magnets. 6. The bypass cryostat will be installed and the TCLD collimator will be inserted as

last component to be installed. 7. The alignment of the TCLD and cryo-bypass will be carried out from the both

adjacent cryostats. Please note that during the smoothing activities of the cryo-magnets in the LHC (end of LS2), if one of the connection cryostats is re-aligned (vertical or radial), the TCLD and cryo-bypass may also need to be re-aligned.

8. After this pre-alignment, the connection cryostat full assembly smoothing w.r.t. the adjacent components will be performed once all interconnections are closed, and the sector has been cooled down during the regular arc smoothing activity.

9. Roll measurements can only be performed by adding an inclinometer on a specific cylinder interface located on the plate that supports the survey socket on the tunnel transport side and on the double jack side.

To do all alignment operations described above, the MAD-X survey file providing the beam positions of the components must be available at least two months before any survey activity in the LHC tunnel, this will be possible only if the LHC layout database will be updated with the needed information at least a month in advance the deadline for the delivery of the MAD-X survey file. Drawings giving the positions of the jacks heads with respect to the component beam points must be available at least two weeks before the jack marking in the LHC tunnel.

3.5 CABLING The nQPS instrumentation and interlock cabling need to be modified. All cables going through the cable tray mounted on the connection cryostat must be re-routed to one of the cables trays on the tunnel ceiling to not interfere with maintenance operations of the collimators. The modifications to the existing cabling are as follows: P2 left side:

o DQLPU-s on B11: Cable to MQ.12L2 Cable to MBA-B12L

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o DQLPU-s on B10: Cable to MQ.11L2 Cable to MBB-A12L2

P2 right side:o DQLPU-s on B11:

Cable to MQ.12R2 Cable to MBB.B12R2

o DQLPU-s on B10: Cable to MQ.11R2 MBA.A12R2

For the cables connecting the BLM detectors, a new cable tray, routed at the wall of the QRL side, will be provided by EN/EL, as well as all the detector connections on both half-cells will be re-cabled by BE/BI.

3.6 Organization of the work during LS2 During LS2 each equipment owner is in charge of the installation of their own equipment. DISMAC will be in charge of the installation and connection of the 11T dipoles full assembly. The detailed procedures for the installation and connection will be given to the DISMAC team. An onsite coordination for the whole activities related to the 11 T dipoleconnection cryostat will be guarantee by WP11 through the activity technical coordination of WP11 (Daniel Schoerling). The role description is provided in [14].

4. IMPACT4.1 IMPACT ON ITEMS/SYSTEMSLHC Layout LHCLSS__0019 - IR2 LEFT, CELLS C8.L2 TO C11.L2

LHCLSS__0020 - IR2 RIGHT, CELLS C8.R2 TO C11.R2The layout database shall be updated accordingly.

Updated layout drawings LHCLSSH__0003 - IR2 LEFT, CELLS C8.L2 TO C11.L2LHCLSSH__0004 - IR2 RIGHT, CELLS C8.R2 TO C11.R2

Interconnection layout LHCQQ_IG0033 – DS zone interconnections, type definitionLHC-LI-ES-0017 – LHC interconnections naming and position convention

Cryogenic layout LHCLSQR_0022 – P&I diagram of DS2 leftLHCLSQR_0023 – P&I diagram of DS2 right

Vacuum layout LHCLSVI_0020 – Schematic layout vacuum instrumentation, LHC arc and dispersion suppressorLHCLSVI_0026 – Schematic layout insulation vacuum instrumentation, IP2 right and left

Main dipole chain No impact

Cryogmagnet documentation

LHC-LE-ES-0001 - Connection cryostats for LHC Dispersion Suppressors (DS)LHC-LE-ES-0002 - Instrumentation in the Connection cryostat (LE)

MP3 No impact

Survey Survey drawings need to be updated

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4.2 IMPACT ON UTILITIES AND SERVICESRaw water: No impact

Demineralized water: No impact

Compressed air: TE-VSC: New sector valves feeding require compressed air cabling. A plug for compressed air close in less than 2m from the location of the sector valve has to be available (responsibility of EN/CV).

Electricity, cable pulling(power, signal, optical fibres…):DEC/DIC: TE-VSC: DICs (reference RQF0912879 already requested and approved)

Racks (name and location):

The racks to be installed, displaced and removed are listed in Table 1-4.

Vacuum (bake outs, sectorisation…):

All changes of the vacuum layout are defined in [6].

Special transport/ handling:

The equipment listed in Tables 1, 2, and 3 needs to be transported and handled in the tunnel and on ground.

Temporary storage of conventional/radioactive components:

The de-installed equipment (Table 4, connection cryostats) may be radioactive and has to be stored.

Alignment and positioning:

Marking of the beam points and new jacks heads projections on the ground floor, aligning the jacks’ heads at their nominal position, initial alignment of the components, then plus smoothing (cold temperature) w.r.t. adjacent components. Marking the new slot and alignment after installation.

Scaffolding: No impact

Controls: TE-VSC: New gauges and valves to be integrated in SCADA and VAC LDB update.

GSM/WIFI networks: GSM should be available during the activity as communication means complementary to the red phones in case of emergency.

Cryogenics: The impact on cryogenics is described in detail in Section 3.43.

Contractor(s): No

Surface building(s): No impact

Others: The N-line as well as the contained 600A and 6kA superconducting busbars may be may be around 8 cm too short due to the required deviation in the TCLD section. A solution to this issue is currently under study.The procedures and equipment to be developed are under the responsibility of WP11. The SIT team of DISMAC will perform the required work in the tunnel.

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5. IMPACT ON COST, SCHEDULE AND PERFORMANCE5.1 IMPACT ON COSTDetailed breakdown of the change cost:

The total cost of the deliverables of WP11 required for the change described in this ECR is borne by the HL-LHC project.

Budget code: BC Unit Description92518 TE-MSC-CMI HL-LHC-WP11 Cryostat (Personnel)92581 TE-MSC-CMI HL-LHC WP11-CCC-Connection Cryostat

with Collimator (includes transport)92606 TE-MSC-CMI HL-LHC WP11-CCC-Connection Cryostat

with Collimator (spares)92518 WP11 cryostat (personnel)92573 WP11 cryostat (components), including

vacuumBC Unit Description

92581 TE-MSC-CMI HL-LHC WP11-CCC-Connection Cryostat with Collimator (includes transport and TE-VSC activities) The transport of the CC from the top of the pit to the position and installation on its jacks is to be covered by WP15 BC91278 for installation and 91275 for de-installation

92606 TE-MSC-CMI HL-LHC WP11-CCC-Connection Cryostat with Collimator (spares, includes TE-VSC activities)

92573 TE-MSC-CMI WP11 cryostat (components), only for cryo by-pass of CC

92518 TE-MSC-CMI HL-LHC WP11 Cryostat (Personnel) (2/3)92609 TE-MSC-CMI HL-LHC WP11 Cryostat (Personnel) - CONS

(1/3)

5.2 IMPACT ON SCHEDULEProposed installation schedule:

The LEBR.11L2 will be dismantled May 2019 and LECL.11R2 in August 2019 both will transit via the PMI2.P2 right side: September 2019 (installation), transit via P4 (LEP) and P2 (LEN), +3.5 months (installation of the deliverables of WP11), +1 month complete installation with collimatorP2 left side: June 2019 (installation), transit via P4 (LEP) and P2 (LEN), +3.5 months (installation of the deliverables of WP11), +1 month complete installation with collimator

Proposed test schedule (if applicable):

The full test of the deliverables will be performed on surface before the installation starts.The quality control (QC) in the tunnel is included in the schedule. The ELQA tests are part of the machine commissioning.

Estimated duration: See above

Urgency: Not applicable

Flexibility of scheduling: In case the cryostats are ready for installation before the planned date, the planning may allow installing them earlier. In case the cryostats are ready for installation after the planned date, LS2 has

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to be extended according to the current baseline planning. A study how to compress the installation time is currently ongoing to gain some contingency in the planning.

5.3 IMPACT ON PERFORMANCEMechanical aperture: No impact on beam aperture is expected as the aperture has not been

decreased with respect to the LHC baseline.Impedance: Impedance studies were performed and presented at WP2

(https://indico.cern.ch/event/743627/) and WP11 as mentioned in the ECR. Measurements of the TCLD prototype were done this summer. The vacuum connections were already optimized from an impedance point of view, and impedance contributions expected from the connection cryostat are acceptable.

Optics/MAD-X No negative impact on beam dynamics is expected. The LHC reference MAD-X file needs to be updated and the exact positioning of cryostats has to be agreed on which will be done only after the LHC layout database will contain the needed information.No impact

Electron cloud(NEG coating, solenoid…)

No impact on the e-cloud effect is expected.

Vacuum performance: No impact on vacuum, cryogenic beam vacuum.

Machine protection No impact.

Cryogenics No impact.

Others: No impact.

6. IMPACT ON OPERATIONAL SAFETY6.1 ÉLÉMENT(S) IMPORTANT(S) DE SECURITÉRequirement Yes No CommentsEIS-Access X

EIS-Beam X

EIS-Machine X

6.2 OTHER OPERATIONAL SAFETY ASPECTSHave new hazards been created or changed?

TE-VSC: The copper cold line in the bypass cryostat will be added (pressurized equipment).A break of cold-mass helium towards the cryostats’ insulation vacuum space has been identified as a risk, with a MCI mass flow of 30 kg/s at 90 K [6].

Could the change affect existing risk control measures?

The hazard is of the same kind and of the same order of magnitude as for the currently installed device.

What risk controls have to be put in place?

To mitigate the risk of overpressure, safety relief devices are installed (see Section 3.3).

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The conformity of the pressurized equipment is being addressed by HSE acting as notified body.HSE will deliver the safety clearance for operation and assess the conformity to the European PEDThe main dipole circuit are in the interlock for powering phase II.The cool down permits will be delivered to allow the safe cool-down of the sectors 67 and 78.A detailed connection cryostat Safety Assessment Form has been prepared [15].

Safety documentation to update after the modification

All the safety documentation asked by the notified body will be archived in EDMS: https://edms.cern.ch/project/CERN-0000183369

Define the need for training or information after the change

No change required for the LHC online training course. The teams intervening on the new equipment need to be trained.

7. WORKSITE SAFETY7.1 ORGANISATIONRequirement Yes No CommentsIMPACT – VIC: X TE-MSC (Sandrine Le Naour) needs to trigger the VIC (Visite

d’Inspection Commune) and create the IMPACT.Operational radiation protection (surveys, DIMR…):

X The area will be surveyed by RP and it is expected that the intervention will be performed under ALARA level 1.

Radioactive storage of material:

X It is expected that the activation level will allow storing the material in a fenced storage area (supervised radiation zone). Therefore, the radioactive material can be stored in building 180.

Radioactive waste: X Volume of radioactive waste will be generated by the worksite itself and will be very limited in volume.The removed cryostat will be kept as spare.Vacuum cleaner for radiological area needed.

Non-radioactive waste: X Very limited

Fire risk/permit (IS41)(welding, grinding…):

X The fire permits and the fire mitigation procedures will be defined during the VIC.

Alarms deactivation/activation (IS37):

X The alarms deactivation or activation will be defined during the VIC.

Others: X This task will be subjected to the WPA coordinated by the LHC coordination team in the framework of the LS2 activities.

7.2 REGULATORY TESTSRequirement Yes No Responsible

GroupComments

Pressure/leak tests: X HSE

TE-VSC

Work is organized by PSO and was delegated to Arnaud Foussat; PED to be followed.

Complete leak test will be performed on the

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entire arc during installation phase.Electrical tests: X TE-MPE Standard procedures will be applied as part of

the main dipole circuit tests of LHC.Others: X BE-DSO PIC will be validated during the DSO tests.

7.3 PARTICULAR RISKSRequirement Yes No CommentsHazardous substances (chemicals, gas, asbestos…):

X

Work at height: X To be determined during the VIC.

Confined space working: X

Noise: X

Cryogenic risks: X The sector will be warmed up and emptied before installation.

Industrial X-ray(tirs radio):

X No X-ray testing will be performed in the tunnel. Welds will be inspected only optical with a camera.

Ionizing radiation risks (radioactive components):

X All removed equipment and waste will be tracked by TREC.

Electrical risks: X

Others:

8. FOLLOW-UP OF ACTIONS BY THE TECHNICAL COORDINATIONAction Done Date CommentsCarry out site activities:

Carry out tests:

Update layout drawings:

Update equipment drawings:

Update layout database:

Update naming database:

Update optics (MADX)

Update procedures for maintenance and operations

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Update Safety File according to EDMS document 1177755:Others:

9. REFERENCES[1] G. Apollinari et al. (eds.), High-Luminosity Large Hadron Collider (HL-LHC), Technical

Design Report V. 0.1, CERN-2017-007-M. [2] Roderik Bruce et al., ECR for installation in IR2 of dispersion suppressor collimators

(TCLD), LHC-TC-EC-0012.[3] C. Bahmonde, Needs for shielding in the connection cryostats in IR2 DS, 14 th HL-LHC

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[4] M. Gonzalez de la Aleja (WP15), WP11: POINT2 Connection Cryostat Full Assembly Integration Study, EDMS 1904996.

[5] Giuseppe Bregliozzi and Eric Page, “New Vacuum Pumping Ports in the ARCs linked to the 11T and TCLDs Installation”, EDMS 1966384 (LHC-V-EC-0015), https://edms.cern.ch/document/1966384/.

[6] Orlando Santos; Eric Page; Pablo Santos Diaz, “Vacuum layout for the installation of TCLD, 11 T & connection cryostat”, EDMS 1869428.

[7] A. Carvalho and G. Riddone, “Clarification on the cost sharing between the WP11 and WP5”, EDMS 2082302.

[8] M. Chorowski et al., “Upgrade on risk analysis following the 080919 incident in the LHC sector 3-4”, CERN/ATS/Note/2010/033.

[9] P. Cruikshank et al., New protection scheme and pressure relief-valve staging of the LHC insulation vacuum enclosure following the 19th September 2008 incident, CERN /ATS/Note/2010/057 (TECH) 2010-12-01

[10] P. Cruikshank et al., Installation of Additional Pressure Relief Devices on the Cryostats of the LHC Arcs and DS, LHC-QJ-EC-0002 (EDMS #1291202).

[11] Rob van Weelderen, “Insulation vacuum safety for HiLumi magnet cryostats”, EDMS 2110660.

[12] N.M. Koziol, DN200 valve with two spring, EDMS 2067605.[13] B. Bradu, Additional instrumentation for cryogenics beam-induced heat load

measurements, LHC-QI-EC-0009, https://edms.cern.ch/document/LHC-QI-EC-0009.[14] A-P. Bernardes et al., Activity Technical Coordination during LS2, Role description,

ACC-PM-MG-0002, EDMS 2020003.

[15] A.V Craen, D.D. Duarte, N Grada, System Safety Assessment Form, EDMS 1971675.