ST TECHNICAL COMMITTEE (STTC)

Compte rendu n° 44 de la réunion du 02/07/2001

1. Approval of the minutes of the last meeting

The minutes of the last meeting were approved.

2. Matters arising from the last meeting

2.1. SPS smoke extraction tests 

The SPS smoke extraction tests have been organized and gave a mixed result. The three extraction units worked perfectly but pulsing was only available at a single speed, corresponding to the minimum boundary conditions.
According to the measurements performed during this test, it was suggested to try calibrating the pulsing speeds in points 2, 4 and 6 with the objective to cope with the available power supply. In case of this approach would fail, a table of the power needed will be transmitted to the EL group for action. 

As the control part of this project is now under control, a new project leader was appointed during the meeting: M. Nonis. He is in charge of the whole project.

3. TCR Operation (H. Nissen) (see transparencies)

H. Nissen presented the main events that have affected the accelerators between 2/05/2001 and 01/07/2001:

3.1. Problem with demineralised water in TOF experiment (28/05 at 13:41)

This problem was due to a flood detector in the target area and stopped the TOF experiment. The faulty element has been replaced and the problem is now solved.

3.2. Power cut in Meyrin (02/06 between 9:59 and 15:00)

The fault occurred on a transformer in SHM18 but was not detected. It caused a defect on the main 66 kV transformer in the BE substation and as a result 7 power cuts were generated, which affecting a lot of equipment of the Meyrin site between 10:00 and 15:00.
J. Pedersen explained that this incident was in fact caused by a breakdown of a set of cable ceiling end and some selectivity problems on the 66 kV network. The 7 power cuts corresponded to the 7 tries to find a supply source. He noticed that only the PS accelerator was affected by this problem.
Finally the selectivity problem on the 66 kV network has demonstrated the need of training of the TCR operators. This will be performed in the next few weeks.

3.3. Stop of the cooling station 378 (03/06 between 20:40 and 17:30)

The cooling station 378 was stopped because of a water leak default and affected the TOF cooling station. It took a very long time to try locating the leak. In addition, this operation failed and the refilling of the entire circuit was extremely long. Later on, the fault was identified on a safety valve in building 378.

3.4. Power cut in the 48 V network (07/06 at 17:20)

Some work in BE9 caused a cut of the 48 V network, which stopped the LEP, the SPS and the North Area. H. Nissen pointed out that it took a long time to get access to the BAs and reset the alarms. Indeed, all the BAs were locked.

3.5. Network problem in TOF experiment (11/06 between 20:10 and 00:06)

A network problem occurred in a hub that controlled many data, among themselves the equipments' alarms. This problem caused a disconnection of all the TOF equipment that were passing through this hub.

3.6. Water leak in the Booster (16/06 between 8:45 and 16:40)

A water leak occurred in the tunnel. R. Principe explained that Gematec stand-by duty reacted quite fast but they wer first blocked by an access problem to the tunnel. They encountered then some difficulties in restarting the installation despite the fact that they have been trained on this system. ST-CV will send a note to Gematec at this subject. 
This problem also demonstrated the need of a radio piquet to manage the entry into the tunnel.

3.7. Power cut in the SPS and North Area (22/06 between 15:21 and 15:30)

The fault was produced in BE9 and has disturbed the cooling tests of the SPS.

3.8. Default on SPS water temperature (23/06 between 10:18 and 11:00)

The TCR received a call from SM18 indicating that the water was too hot and the equipment rising in temperature. M.C. Morodo Testa and D. Blanc intervened and solved the problem by restarting the fuzzy logic of the variator.

3.9. Low pressure on SPS primary water (29/06 between 11:40 and 13:07)

The default was caused by a communication problem between SIG and ST/CV automates, which disturbed the delta P. As a result, SIG was not able to control water pressure and asked for a stable consumption without any increase of power. 
M. Wilhelmsson explained these first difficulties by the change of range in the CV network.

3.10. Disconnection of the SPS compensator (30/06 between 15:27 and 16:00)

The SPS compensator disconnected at the maximum intensity. TCR was informed on this problem by the PCR. The compensator was indeed not fully supervised by the ENS system at that time. It should be operational this week.

This failure highlighted two technical aspects:

• the complexity of the reactance,
• the calculations of protection level.

The breakdown itself was in fact due to an internal isolation fault on one of the two reactances, a very old equipment, which confirmed ST-EL worries. J. Pedersen recalled that the third reactance, now used as a spare, will be needed in the future for the injection tunnel.

3.11. Not stable TDS (between 28/05 and 10 /06)

During the last period, the TDS system was not very stable due to the recent increase of the load. A cleaning of the signal is really needed, as well as a redefinition of all the values. This represents a really heavy job.
Nevertheless the problem should be solved rapidly as no alarms get through during the breakdown.

3.12. High water temperature in BA1 and BA3 (02/07)

It appeared this morning that the temperature of the main magnet circuit was higher than 40 °C. At the time of the meeting, ST-CV group was still investigating on the problem.

4. Status report on PS operation (D. Gueugnon)

The PS is now on operation and delivering a beam to the SPS, AD and Isolde. The technical stop on 6/6 ran very well.

The only problem to be noticed was an access control default on a door between the MCR and AD experiment. The result of this default was a continuous sound in the control room during the entire week-end. G. Kowalik explained that the problem was due to a breakdown of the GG4 software associated to the door.

D. Gueugnon announced that nTOF experiment has been stopped for two weeks.

He also congratulated J. Kuhnl-Kinel for his coordination work in the PS area.

5. Post mortem of the SPS shut-down (P. Collier)  (see tranparencies)

During this last shut-down an incredible amount of work has been performed. The result is positive: within 2 hours of starting, circulating beam was established.

P. Collier detailed the main activities performed during the last shut-down:

• in the tunnel:
  • removal of lepton equipment (kickers, transfer lines),
  • RF modifications,
  • civil engineering in SPS,
  • infrastructure works in ECA4,
  • installation of 1000 impedance reduction shields by removing about 8000 t of dipoles,
  • LSS4 extraction equipment,
  • changes in the machine layout,
  • cabling and piping work,
  • ECA5 shielding wall,
• in surface:
  • water project,
  • BE renovation project,             
  • power converter renovation project: 70 power converters have been refurbished and reinstalled,
  • BA1: re-organization of the kicker zone,
  • BA2: damper modification,
  • BA3: Faraday cage renovation,
  • BA4 and BA7: preparation works for LHC.

A lot of things ran very well:

• The planning of the project started early and regular meetings have taken place. A detailed planning comprising all the works has also been established.
• The communication between SL and ST was good.
• The majority of works ran smoothly.
• The traceability system implemented to fulfil the new INB regulation was simple and well behaved by everybody.
• The collaboration between different groups and divisions worked well.

On the other hand some points still need to be improved:

• The site supervision was not sufficient and the cohabitation between different activities was difficult. In addition each group should organise the protection of existing installations before performing some dusty work.
• Some problems of rubbish collection occurred at the beginning of the project.
• The storage of radioactive waste was problematic. A dedicated building for radioactive waste is now on project.
• The value for money was not checked correctly because of the large number of OSVCs and TIDs sent on the same time to the management of the project.
• The quality control was performed by SL on the final product. The reason for paying for the quality control and the supervision of the contractor was not always well understood. Weekly meeting did not directly deal with quality control.
• Poor communication still persisted in some areas, for instance the interventions on compressed air in the tunnel without information to other services. M. Wilhelmsson precised that the information was diffused through a "Note de Coupure". If some other services need this information, the mailing list just need to be updated.
• Non respect of the planning by one group affected all the subsequent activities, i.e. repair of the floor in BA4. 

In addition, P. Collier mentioned some other difficulties that occurred:

• Leaks in the roofs of the BAs: ST division is aware of this problem but it can only be solved rapidly by a dedicated budget allocation, otherwise the roofs will be refurbished one by one as soon as some budget is available.
• The end of the shut-down was chaotic with all the groups pushing urgently their installations into service.
• The results of the SPS Safety Upgrade were not convincing, especially the test in BA2.

He concluded that the schedule has been maintained despite the limited resources. An overall planning of all the activities is really needed. Big improvement in the communication between ST and SL should also be noticed.

The discussion concentred then on the control of work. It clearly appeared that too few ST people were present on the work site. Some training should be organised for the new generation. 
J. Pedersen pointed out that ST division should rather supervise companies more than works. Due to a lack of resources, groups often have to choose between a full worksite control and a high level project follow-up.
But problems on the work site occur every day (cohabitation between activities, protection of equipment, safety, etc.) and somebody is really needed on the site to solve all these problems and to make sure that the firm is doing his job completely. 
Coordination of activities on the worksite should also be dealt locally.
On the machine side, 3 technicians spent between 1 and 3 hours a day on the site controlling work progress.

A. Scaramelli stated that ST division has to revise its organisation in order to dedicate more resources to the worksite supervision. In addition all the result oriented contracts have been adjudicated to the lowest bidder. ST division can't escape from controlling them in order to keep the contracts in hand.
As part of this analysis, the SL file will be useful to understand where the problems are located and find a good way of communication with SL. It has been agreed with S. Myers to analyse clear facts.

Concerning the value for money, one of the CERN duties consists of checking that the work has been properly done by the contractor and to activate the according process of payment.

6. Starting of the electrical operation contract (J. Pedersen)

The electrical operation team is made up of 7 people in charge of the on-site work. A training period will be necessary during the first weeks. The training will be given by the ST-EL operation team (4 staff members and 3 industrial support personnel).
In addition, until the end of the year, a CERN staff member will systematically accompany the contactor's personnel on all the stand-by interventions.

7. Status report on ST alarms on the PS area (S. Campbell)  (see transparencies)

S. Campbell precised that only ST-CV alarms are concerned.

He first listed the installations connected with a synoptic, mainly:

Some other installations are still connected but without synoptic:

In addition, some installations are simply not connected:

One known problem concerns the loss of  API215 data after the power cut that occurred on 7th June. As the station was restarted before the previous data could have been inserted, the pumping station needed to be stopped in order to correctly install these data. This means that the machine also had to be stopped during this operation.

To solve some of these inconsistencies ST-CV group has launched the COSPCU project, which includes demineralised stations of West Area, main magnet, SW18, chilled water stations 355 and 513. It has to be noticed that building 378 and TOF installation are not part of this project.

S. Campbell gave more information on the installations in building 378. It is possible for the TCR to rearm a fault without reseting the equipment. But as the operators don't get any information on the state of the equipment before the fault, it is very difficult for them to know exactly what to do.
R. Principe explained that a failure in the demineralised water production does not affect any machine. It gives ST-CV some time to intervene. But he recognised that it is not ideal to have a single alarm in this building. But the procedure is clear : to call the Gematec stand-by duty.

In the next future, all the installations should be connected. This represents a very heavy job for the TCR, to be done in collaboration with ST-CV. The deadline is fixed to Easter 2002.

8. GTPM - Gestion Technique Panne Majeure (M. Bätz)

This subject will be presented during the next STTC meeting.

9. ST-CV projects in the West Area (M. Battistin & G. Lion)

M. Wilhelmsson explained that ST-CV is preparing a whole project for the West Area. He introduced G. Lion who will develop the technical part and M. Battistin in charge of the budget.

9.1. Technical aspect  (see tranparencies)

G. Lion first presented the elements making up the building 378's installations:

• water chillers,
• demineralised water installations,
• cooling towers,
• mixed bed cartridges regeneration plant,
• heat exchangers,
• pumping station.

9.1.1. Cooling towers

The old cooling towers need to be suppressed. It has been first envisaged to use the cooling towers located in building 274. This implied to connect the two buildings through the technical galleries. G. Lion presented some photos of the technical galleries showing that there is no really space for these pipes and that permanent changes from side to side are necessary. He announced a cost estimate of 550 KCHF for such a project.
He suggested rather to refurbish the existing 10 MW cooling tower (fan and pump to rebuild, pipes to install).

A study of the hydraulic circuit gave an estimate of 50 KFF to dismantle the old connection. The power needed in the area represents only 4 MW.

9.1.3. Freon elimination

Three groups were used to cool the ISR area. They contain freon R-12 that need to be eliminated by a licensed company. The cost of such a project varies according to the elimination channel:

• 20 KCHF if recycled,
• 120 KCHF if contaminated,
• a Greek company offered to pay 10.5 CHF by kg (representing a total of 7'500 CHF), transport included, for the freon R12.

9.1.4. Demineralised water installations

G. Lion suggested to install demineralised cavities under these three groups. The floor in the basement can support the weight of the cavities.

Globally, demineralised water installations are well maintained but the valves do not comply anymore with the NF standard. The complete change of these valves is estimated to 80 KFF. G. Lion recalled that this installation provides water for the SPS and central heating stations.

9.1.5. Conclusion

A huge maintenance on the installations is really necessary. Present needs should be considered for future projects.

9.2. Financial aspect  (see tranparencies)

This project is divided into three parts:

• chilled water,
• demineralised water,
• cooling towers.

9.2.1. Chilled water installation

The water chillers comprise two groups of 1 MW each. The main users are electrical tests in building 377 and TOF project. Their needs are estimated to about 4 MW. This value should remain stable in the future.

Some parts of the installation need to be renewed :

• electrical connections,
• the 3000 V motor with obsolete switches and few spare parts,
• the R11 cooling refrigerant.

The new project consists of :

• the installation of two new chillers,
• the refection of the electrical network,
• the installation of a new control system,
• the installation of two new power transformers.

It is estimated to 1,6 MCHF. This part of the project should be discussed with LHC to confirm the needs. 

J. Pedersen precised that 1 MW of electrical power will be needed. This implies the installation of one transformer and one switchboard.

9.2.2. Demineralised water

The installation is in a good state. The only interventions to be performed will concern : 

• the change of the control system,
• the revision and replacement of valves.

This part concerns more maintenance and will be taken from the operation budget.

9.2.3. Cooling towers

Two operations are planned:

• dismantling of the installation,
• asbestos removal.

The estimate arounds 500 KCHF.

10. Any Other Business

R.A.S.

S. Prodon

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