Chapter 15 Integration and (De-)installation

Transcription

1 Chapter 15 Integratin and (De-)installatin P. Fessia and S. Weisz CERN, Acceleratr & Technlgy Sectr, Geneva, Switzerland 15 Integratin and (de-)installatin 15.1 Gegraphical distributin f HL-LHC upgrade interventins The HL-LHC will require mdifying the machine and infrastructure installatins f the LHC in several pints alng the ring, in particular P1, P2, P4, P5, P6 and P7. While the equipment in P1, P5, and P6 are meant t be installed during Lng Shutdwn 3 (LS3), the mdificatins and imprvement in P4, P7 (as far as the supercnducting links are cncerned), and P2 shall be cmpleted during LS2 and be peratinal fr LHC Run 3. Belw we list the activities required pint by pint accrding t the presently freseen chrnlgical rder. P8 will have minr mdificatins during LS2, which are nt cnsidered here Pint 4 P4 will be equipped with a new crygenic plant dedicated t the RF systems (and ther crygenic equipment that might be installed in IR4) (Chapter 9 Sectin 9.5). The installatin will require: - surface: installatin f the warm cmpressrs systems in SU4; - junctin surface t the undergrund cavern via PX46; - undergrund: installatin f the cld bx in TX46 (see Figure 15-1); - cnnectin between the cld bx and QRL via UX45; - QRL mdificatin between 25 m and +25 m arund IP4. Figure 15-1: Vlume reserved fr the installatin f the new cld bx unit dedicated t RF system cling (light blue). Crrespnding authr: Pal.Fessia@cern.ch 229

2 The slutins presently adpted make the maximum use f existing vlumes, requiring very limited civil engineering wrk, mainly devted t the ruting f the piping frm SU4 t SX4 and t the vertical wall f PX46. The whle system installatin shall be cmpleted fr the end f LS2. Figure 15-2 prvides a schematic f the P4 buildings Pint The hrizntal supercnducting links Figure 15-2: View f the LHC civil wrks at P4 In P7 tw hrizntal SC links will be installed in rder t electrically feed the 600 A circuits cnnected t the tw DFBAs (DFBAM and DFBAN). The related pwer cnverters will be installed in TZ76 and via shrt warm cables will be cnnected t the supercnducting link. The tw supercnducting links will then run fr abut 220 m in TZ76 and then enter the LHC machine tunnel via UJ76. They will then be ruted fr abut 250 m in the LHC tunnel in rder t be cnnected t DFBAM and DFBAN (Figure 15-3). The whle installatin shall take place during LS2; n lng access perid is available befre that time. Pssibilities t advance part f the interventins in the year end technical stp (YETS) shall be evaluated, and the time fr radilgical cling will be used fr the preparatin f the interventins in the LHC tunnel. Sme preparatry wrk has been perfrmed already during LS, in particular the remval f the chill water pipes. This system was nt f use in P7 and its dismantling has made space available fr the SC link installatin. Figure 15-3: View f the freseen installatin f the supercnducting link system at P7. Pwer cnverters in TZ76, ruting f the link frm TZ76, via UJ76 t RR

3 In rder t perfrm the installatin f the SC links in the LHC tunnel the need fr de-installing part f the present equipment (as a precautin fr aviding pssible damage) still needs t be fully assessed New cllimatrs in the dispersin suppressr In rder t prtect the supercnducting magnets (excess heat depsitin) frm ff-mmentum prtn leakage frm the main cllimatr system itself, sme special cllimatrs must be installed in the dispersin suppressin regin, i.e. in the cntinuus crystat. The evaluatin f the real need fr this mdificatin will be cmpleted based upn the first results f LHC Run 2. Unless Run 2 shws dramatic and unexpected results, the installatin will eventually take place during LS3. In rder t cpe with the prtn lsses in the dispersin suppressr area it has been decided t install tw cllimatrs n each side f the IP. In rder t d s it will be necessary t: - de-install MB.B8L7 plus MB.B10L7 and the symmetric MB.B8L7 plus MB. B10L7; - substitute each remved diple with a unit cmpsed f tw 11 T diples (Chapter 11) separated by a crygenic bypass; - install the cllimatr n the tp f the crygenic bypass (Chapter 5). The magnet installatin will als prbably require a new dedicated quench prtectin system and a trim circuit with its wn pwer cnverter. The lcatin and the installatin apprach fr this equipment are still under evaluatin, but very prbably it will be lcated in the nearby RR Pint 2 In rder t limit the heat depsitin frm cllisin debris in the supercnducting magnets during the in run, cllimatrs in the dispersin suppressr will als be installed in P2 (Chapter 5). In this case the installatin will take place nly in ne slt n each side f the IP replacing MB.A10L2 and MB.A10R2. This equipment is necessary fr LHC Run 3 with ins, t allw Alice t fully prfit frm the upgrade carried ut during LS2. Therefre, the installatin f the unit cmprising the 11 T diples and the cry-bypass needs t be cmpleted during LS2. The cllimatr itself can be assembled at the same time r later in a shrt technical stp r in a YETS. All the ther issues listed in Sectin are applicable, but the prximity services will prbably be installed in the UAs Pint 6 In P6 the tw Q5 quadruple magnets will be mdified in rder t fulfil the needs f the new HL-LHC ATS ptics. Tw ptins are presently under evaluatin leading either t the exchange f the present Q5 with a new Q5 r the installatin f Q5-bis near the currently perated Q5. Bth ptins will require the lcal reshuffling f the vacuum layut and pssible mdificatins t QRL. The interventin in P6 is required t be cmpleted in LS3, but ptins t anticipate it in LS2, bth t limit the amunt f wrk during LS3 and t reduce persnnel expsure t radiatin due t the prximity t the beam dump line, are under study Pint 1 and Pint 5 The largest part f the new equipment required by the HL-LHC perfrmance bjectives will be installed in P1 and P5. The items t be installed and actins t be carried ut are listed belw, and are applicable t bth pints if nt therwise specified. The list is rganized by gegraphical areas LHC machine tunnel De-installatin. 231

4 - All the machine equipment frm the interface with the experimental cavern (TAS included) until the DFBA (included) requires remval. - The present QRL will be remved frm the same area. A new return mdule will be installed in the ex- DFBA area in rder t allw separatin f the clant flws cming frm the LHC QRL and ne f the new HL-LHC QRLs that will feed part f the machine frm Q1 t Q6. This return mdule shuld als prvide the pssibility, if required, t cnnect the LHC QRL with the newly installed ne, ensuring an increased level f redundancy in the system. - Services linked t the abve de-installed equipment will be remved and new nes shall be installed: Preparatin fr re-installatin. - Minr wrks culd be necessary in rder t prepare the tunnel flr and wall t receive the installatin f the new equipment (fr larger and dedicated civil engineering wrks as described belw). Installatin f the new equipment, prbably in the fllwing sequence: - TAXS; - services; - QRL with related valve and service mdules; - hrizntal supercnducting links frm the DFM t the magnets t be fed; - Magnets and crab cavity supprt system; - magnets and crab cavity; - distributin feedbxes (DFX) fr the Q1 t D1 magnet system and distributin feedbxes (DFM) fr the D2 t Q6 magnet system. The sequence f installatin f the vertical supercnducting links t be cnnected t the DFX and DFM still need t be assessed accrding t the ptins retained fr their ruting. In additin t the interventins described abve, it may be necessary t strengthen the cllimatin system with new cllimatrs in the dispersin suppressr as described fr P7 in Sectin Existing LHC tunnel service areas The RRs n bth sides f P1 and P5 will need t be re-rganized, and in particular the fllwing will be necessary. - T de-install the pwer cnverter and ther related systems (e.g. the quench detectin system) linked t the pwering f the remved LHC matching sectin. - T re-rganize the remaining equipment in rder t have the mst efficient space ccupatin, increase if necessary the radiatin shielding, and place the mst radiatin-sensitive equipment in the mst prtected areas. Pssible equipment replacement with new radiatin-hard elements can be envisaged. At present n civil wrk interventins are freseen in the RRs areas New HL-LHC tunnel service areas The installatin f the new crygenic plant in P1 and P5 will have tw bjectives: - t prvide independent and redundant cling capacity t feed the final fcus and matching sectins left and right f each f the tw high luminsity insertins fr the LHC; - t prvide redundancy t the crygenic plant installed t cl the experimental systems. 232

5 The cld bxes shall be installed in undergrund areas. At present the required vlume des nt exist. Therefre cnceptual studies have started in rder t identify the best ptins fr building new undergrund caverns t install this equipment and the related service and cntrl system. Figure 15-4, Figure 15-5, and Figure 15-6 crrespnd t slutins with pwer cnverters in the undergrund areas while Figure 15-7 crrespnds t a slutin with magnet pwer cnverters n the surface (baseline). Figure 15-4: Pssible ptin fr undergrund wrk at P5 including links t the LHC tunnel. This slutin is withut an independent shaft t access t the surface. New structures are in light red, and znes f the LHC tunnel t be impacted by cnstructin the new structures are in green. Figure 15-5: Pssible ptin fr undergrund wrk at P5 including links t the LHC tunnel. This slutin has an independent shaft fr access t the surface. New structures are in light red and yellw, and znes f the LHC tunnel t be impacted by cnstructin f the new structures are in green. Figure 15-6: Pssible ptin fr undergrund wrk at P5 including links t the LHC tunnel. This slutin has an independent shaft fr access t the surface, and a larger cnnectin tunnel fr pssible pwer cnverter undergrund installatin. New structures are in light red and yellw, and znes f the LHC tunnel t be impacted by cnstructin f the new structures are in green. 233

6 Figure 15-7: Pssible ptin fr undergrund wrk at P5 including links t the LHC tunnel. This slutin has an independent shaft fr access t the surface. A crss-sectin thrugh the crygenic equipment is shwn. New structures are in light red and yellw New cnnectin frm the LHC tunnel and HL-LHC service areas t the surface The fllwing cnnectins between the surface and the undergrund installatin shall be made available. - LHC tunnel and crab cavity area t the surface. The crab cavities need t be cnnected t the dedicated RF pwer system and their cntrl system. The present preferred chice is t install these services in dedicated surface buildings (see belw). The undergrund t surface cnnectin will need t huse eight RF caxial cables (each abut 300 mm in diameter), plus the required cntrl cables. Tw ptins are being studied. The cnstructin f eight ducts ver each crab mdule, linking directly the tunnel vault with the surface crab service building. The cnstructin f a shaft where all the previusly listed cables can be hsted tgether. In this case a lcal enlargement f the LHC tunnel will be necessary. Alternatively there will be a need fr the cnstructin f a separate small cavern where the shaft will end. The extra undergrund wrk is necessary t take int accunt that the minimum shaft dimensin is larger than the LHC tunnel diameter. - New HL-LHC service area t the surface. These cnnectins are necessary t link the surface part f the crygenic plant with the cld bx installed in the new undergrund HL-LHC service areas. - Vertical ruting f the supercnducting links. In each pint at least fur supercnducting links will need t be ruted frm the surface t the undergrund areas. Three ptins are pssible and they are listed frm mst t least cnvenient: installatin f the supercnducting links in the same vertical duct linking the crygenic plant t the surface; installatin f the supercnducting links in the same vertical duct linking the crab cavity t the surface; installatin f the supercnducting links in new dedicated vertical ducts New surface installatin The fllwing installatins shall find space n the surface fr P1 and P5 installatins. 234

7 - Crab cavity RF pwer and services hsted in tw ad hc surface buildings (yellw bxes in Figure 15 8). They shall be psitined n the surface, directly abve the tunnel psitin where the crab cavities will be installed. There will be tw surface buildings fr each pint, ne n the lefthand part f the machine and ne n the righthand part. The surface extremities f the ducts/shaft fr the crab cavity caxial leads r shaft shall be hused inside this building. The part f the building with the cntrls system shall be electrmagnetic shielded. - Crygenic installatin. The warm cmpressrs and the ther parts f the crygenic plant shall be installed n the surface. - Pwer cnverters, upper extremities f the supercnducting links, prtectin systems, and energy extractin system related t the circuits fed via the supercnducting link. This area may pssibly be lcated near the surface part f the crygenic plant and in any event n tp f the surface ruting f the vertical supercnducting link. Currently it lks very difficult t find the required space in existing buildings; therefre the cnstructin f new structures t hst the systems listed abve is prbably necessary (Figure 15-9). Figure 15-8: Surface psitin f the tw new crab cavity service buildings (in yellw) at P5 235

8 Figure 15-9: Preliminary study f the LHC P5 building ftprint. Building 1: pwer cnverters and SC link terminals; Building 2: crygenic surface equipment; Building 3: access t shaft. Pssible technical galleries are in light blue. In additin t the abve mentined ptins, a slutin, where the pwer cnvertrs and the crab cavity ancillaries wuld als be installed undergrund, is under study. Such an ptin wuld lead t an undergrund structure f much larger vlume, but the increase in cst culd be partially balanced by a reductin in the number f cres frm the surface t the tunnel, a reductin in the numbers f surface structures t be built, and the simplificatin f the surface wrksite Activity sequence cnsideratins While the sequence f interventin n the undergrund LHC installed equipment (machine and RR) is quite clear and linked t the end f the LHC Run 3, the sequence fr the ther installatin and civil wrk activities is still under evaluatin. The wrksite rganizatin will depend upn the ptins chsen. This is why, in the evaluatin f the selectin f the final slutins fr the undergrund caverns, the cnnectin tunnel t the surface, and the surface building, three main parameters shall be taken int accunt. These are cst, the pssibility f perfrming the wrk in advance with respect t the LS3 start date, and the ease f installatin and cnnectin, since sme ptins culd lead t very cmplex and crss-cnnected installatin wrksites, making LS3 unacceptably lng. 236