The Cooling and Ventilation Group has started the LHC construction work in September 1999 and will get into full activity when LEP will be stopped and dismantled: in total 12 major contracts for an amount of about 120 MCHF will be established to build the needed installations for the LHC. The author will report on the current works that are in progress on the different LEP Points distinguishing between the Ventilation and the Water Cooling installations. The Ventilation work, completed in the new surface buildings in Points 18, is currently held in Points 4 and 5. Point 1 will follow in the near future. The work for the Cooling plants comprehend the pumping stations, the cooling towers and the chilled water production stations in Points 1 and 5, the buried pipes in Points 1 and 4. For all of these activities, an updated report of the progress of the work, of the planning and of the expenses is given. Finally, a short overview of the future activities is presented

Nonis, M

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EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCHORGANISATION EUROPÉENNE POUR LA RECHERCHE NUCLÉAIRECERN - ST DivisionPresented at the 4th ST WorkshopChamonix, France, 30 January - 2 February 2001CERN-ST-2001-02731 January 2001CONSTRUCTION PROGRESS OF THE COOLING & VENTILATIONIN THE LHC PROJECTM. NonisAbstractThe Cooling and Ventilation Group has started the LHC construction work in September 1999and will get into full activity when LEP will be stopped and dismantled: in total 12 majorcontracts for an amount of about 120 MCHF will be established to build the neededinstallations for the LHC. The author will report on the current works that are in progress onthe different LEP Points distinguishing between the Ventilation and the Water Coolinginstallations. The Ventilation work, completed in the new surface buildings in Points 18, iscurrently held in Points 4 and 5. Point 1 will follow in the near future. The work for theCooling plants comprehend the pumping stations, the cooling towers and the chilled waterproduction stations in Points 1 and 5, the buried pipes in Points 1 and 4. For all of theseactivities, an updated report of the progress of the work, of the planning and of the expenses isgiven. Finally, a short overview of the future activities is presented.21 INTRODUCTIONSince September 1999 the Cooling and Ventilation group has started the most important activitiesrelated to the LHC Project; the peak of the work will be between 2001 and 2004, when the majorinstallations and plants will be commissioned. During te time LEP was still in operation, no activityhas been possible in the underground; since the LEP will be dismantled in 2001, the CV works willstart in underground areas, as soon as the civil engineering structure will be finished.In the following paragraphs the current activities that are in progress on the different LEP Pointsare reported, distinguishing between the Ventilation and the Hydraulic Cooling installations. Themajor contract for the ventilation system concerns the surface buildings, while for the cooling plants,several work has started in almost all the LEP Points.The contracts established by ST/CV have been determined according to the typology of thework rather than to the surface point where the work has to be done, therefore all the Contractors arerequested to make interventions on several areas.For reason of simplicity, no mention is made to all the “minor” work, i.e. all the activitieslimited in duration, area and cost. The same happens for all what is not strictly related to the LHCmachine and its experiments, i.e. the injection tunnels, CNGS etc.The global amount for all the CV work is estimated to be around 120 MCHF, one third of thembeing already awarded and the remaining will be committed during the next 2 years.2 HYDRAULIC WORKThe hydraulic work for LHC has started for the surface installation in Point 1, 18, 4 and 5, namely forthe cooling pumping station, cooling towers, chilled water production plants and pipework.Each of the following paragraphs is dedicated to one of these activities.In March 2000, the piping work in Point 18 has already been completed, comprehending thefollowing circuits: the raw water (for the cryogenic compressors), the hot water and the fire fightingsupply for buildings SMA and SHM18, connecting them to the SPS cooling loop.2.1 Cooling Towers at Point 1 and 5Demineralised water will be used for the cooling of a large part of the LHC equipment, the cold sourcein the raw water primary circuit being the existing cooling towers. Some new cooling towers (SFbuildings) are under construction in Point 1 and 5 for the ATLAS and CMS Experiments respectively.The make up water for the cooling towers will be provided from the LHC cooling loop via somepumps which are already existing in the tunnel and used for LEP. The raw water circuit will beoperated by a new pumping station installed in the same building (see following paragraph 2.2).The number of cells for each cooling tower is different in the two Points since the differentthermal power is needed: 10 MW are requested for both of the Experiments however in Point 1 thesame set of cells will be used for the SPS equipment located into the BA6 (bldg. 873); this representssome additional 14 MW power. In both cases a spare unit is foreseen.The main parameters concerning the circuit of the cooling towers are listed in table 1. Theoverall dimensions of each cell are 11 by 11 meters per side with a height of 13 meters. The thermalcapacity is 10 MW per cell.The installation in Point 5 has started at the beginning of November 2000 and is due to end byFebruary 2001. The work in Point 1 has started with some delay, on December 2000, upon delivery ofthe Civil Engineering construction. The end of the work is scheduled for March 2001. As mentioned,these cooling towers will be used both for ATLAS Experiment and for part of the SPS accelerator, theschedule is therefore mainly dictated by the SPS Shutdown rather than the LHC one.32.2 Pumping Stations at Point 1 and 5The pumping stations for the primary circuit are located in the same building as the cooling towers, inthe underground floor. The stations are intended to cool the cryogenic compressors, the chilled waterproduction plants and some electronic equipment.The main parameters are shown in table 1; the nominal pressure is 10 bar.Table 1Main parameters for the cooling circuitPointTemperature range°CFlow ratel/sNumber ofcircuitsNumber ofpumpsPoint 1 24-34 750 2 4Point 5 24-34 335 3 6In order to respect the tight schedule the work has started in both the Points in October 2000 andwill finish in May 2001. As for the cooling tower in Point 1 the main constraint for the schedule isrepresented by the restart of the SPS accelerator in June 2001.2.3 Chilled Water Production Plants, Point 1 and 5The needs for ATLAS and CMS are produced in the two SUX buildings by a set of chillers that canprovide chilled (5 °C) or mixed (12 °C) water. The chilled water is produced for electronic equipmentin the underground areas (USA, USC caverns) and for the air handling units, both for the undergroundareas (SUX) and some surface buildings (SH, SXC, SGX, SX). The chilled water production is linkedto a heat recovery system that provides water to pre-heat the air for the underground areas in the airhandling unit located in the same buildings.The parameters for the chilled water circuits are listed in table 2.Table 2Breakdown of the main parameters of the chilled water circuitsPointCircuit/buildingFlow ratel/sPowerMWPressureMpaPoint 1 SUX 67.5 2.10 0.30USA 57.2 0.80 0.30SH/SGX/SXC 41.6 0.48 0.25SU 71.6 1.00 0.30Total Point 1 237.9 4.38Point 5 SUX/SX 95.8 1.70 0.40SH/SGX/SXC 37.2 0.51 0.40USC 20 0.50 0.30Total Point 5 153 2.71The mixed water is produced for equipment in the underground caverns (USA, USC or UX) andfor the racks in the surface buildings SDX and SCX; the parameters for these circuits are reported intable 3.4Table 3Breakdown of the main parameters of the mixed water circuitsPointCircuit/buildingFlow ratel/sPowerMWPressureMpaPoint 1 USA /SDX 166.6 4.2 0.30Point 5 SCX 14.7 0.4 0.30USC/UX 151.9 3.7 0.30Total Point 5 166.6 4.1The installation is composed by 2 chillers per Point, with a cooling power of 2.5 MW each; thecooling of the condenser of the chiller is made by raw water coming from the new cooling towersmentioned in paragraph 1.1. The cooling of the demineralised water is assured by plate heatexchangers.The contract was awarded in the end of 1999, while the installation phase will start in March2001 for Point 1 while the start in Point 5 is foreseen by August 2001, according to the delivery by theCivil Engineering Group. The commissioning is scheduled by January 2002 for Point 1 and October2002 for Point 52.4 PipeworkSeveral contracts for the pipe works in the different LHC Points have been established, the mostimportant is the pipes on Point 1 and 5 (galleries and shafts) and the buried pipes on Point 1 and 4;these pipe networks link the cooling towers, the chilled water production stations and the equipment tobe cooled.The main parameters of these networks are listed in the following table.Table 4Main characteristics of the pipes in galleries, shafts as well as buried pipes.Galleries and shafts in Point 1 and 5TypeConcernedbuildingsDiameter(mm)Material Pressure(bar)Operatingtemperatures(°C)RawwaterSF/SH/SDX/SUX/PX/USA200 - 500 Carbon steel 8 24 – 34ChilledwaterSUX/PX/SUSDX/USA/SGX65 - 300 Carbon steelwith lagging6 6 – 12MixedwaterSUX/PX 300 Stainlesssteel6 13 – 19FirefightingSXC/SDX/SH100-150 Cast iron 15 AmbientCompr.airSUX/SDX 50 Galvanisedcarbon steel10 AmbientDischargewaterPX/SDX 150 Stainlesssteel16 AmbientDemin.waterPX/USA 200 Stainlesssteel16 27 - 375HeliumpipingSH/SD 250 Stainlesssteel20 AmbientBuried pipes in Point 1 and 4PrimarywaterSH1/BA6/SHM4300 - 500 Cast iron 10 24 - 34WastewaterSF1 150 Cast iron 4 12 – 34RawwaterSF1/SHM4 150 Cast iron 10 12 – 22Compr.airSHM4 100 Galvanised 15 12 - 20For the pipes in the galleries and in the shafts the work was started in July 2000 in Point 1(SUX, SD, SH buildings) and will continue until 2004 following the completion of the civilengineering construction. For the buried pipes, the work has started in October 2000 and will befinished in March 2001.3 VENTILATIONWORKThe ventilation work at presents concerns only the ventilation plants for the new surface building. Onesingle contract has been established for that, while the ventilation of the experimental areas and themodification to the existing LEP installation will be object of two coming tenders (see last paragraph)3.1 Ventilation in the Surface BuildingsThis contract has been awarded at the beginning of 1999 and concerns the buildings on almost all theLHC Points. In the following table a list of buildings per Point is given as well as the milestones.Table 5List of surface buildings with a new ventilation plant per Point.Point Building Start of Work End of WorkPoint 1 SGX1, SH1, February 2002 July 2002SX1 October 2002 January 2003Point 18 SD18, SHM18,SMA18October 1999 August 2000Point 2 SMI/SDI2,SUH/SH2February 2002 September 2002Point 4 SDH4, SHM4 September 2000 January 2001SH4 June 2002 January 2003Point 5 SH5, SX5 January 2000 July 2001SGX5, SX5 July 2003 June 2004Point 6 SA6, SHM6 August 2001 November 2001SH6 October 2002 May 2003Point 8 SDH8, SHM8 February 2001 July 2001SH8 April 2002 November 2002The purposes of the units to be installed are mainly the supply and the extraction of the air;some of them will be used in case of smoke removal. The flow rate range is between 750 and 750006m3/h for the supply, between 300 and 8600 m3/h for the extraction and between 15000 and 22000 m3/hfor the smoke removal, according to the needs in the different buildings. The most important units(75000 m3/h air flow rate) have two air channels.The work was started in October 1999 in Point 18 with the SHM building and the schedule isrespected, even though some minor delays with no interference with the overall LHC schedule. Point18 buildings have been completed, work is at present going on in Points 4, 5 and 6.4 IN THE FUTURE?In addition to all the work mentioned in this report, other important contracts will be established in thenext future to complete the preparation of CV installation for the commissioning of LHC.In table 6 an overview of these activities is given with the foreseen schedule; the dates areindicative since for several projects a detailed list of the needs and of the final configuration are stillunder study.Table 6List of future activities to be done in the CV Group for LHC ProjectDescriptionMarketSurveyCall fortenderWork phaseHydraulic plantsModification of the cooling station at Point2,4,6,87/2000 6/2001 2001-2002Stainless steel pipes for demineralised water 9/2000 4/2001 2002-2003Cooling stations for the ATLAS and CMSexperiments5/2000 2002 2003Clear, drain and waste water systems 8/2000 6/2001 2002-2004Ventilation plantsVentilation plants for ATLAS and CMSexperimental areas3/2000 9/2000 2001Ventilation plants for LHC tunnel, LHCb andALICE10/2001 9/2002 20045 CONCLUSIONSGlobally all the work has started respecting the schedule and no major delay is foreseen: the siteactivities have been well monitored with a remarkable effort from all the CV staff involved and thishas let a correct advancement of the work. The final cost is also within the estimations, with noparticular exceed to the contractual amount at the adjudication of the contract. An even bigger effortwill be demanded in the next two years as the work charge will increase.

Construction Progress of the Cooling and Ventilation in the LHC Project

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