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End-cap Closeout Review Stephen Haywood Rutherford Appleton Lab
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7 Dec 2007 End-cap Closeout Review 2 Stephen Haywood Introduction (10’) Support Structure (20’) Services (beyond Disc) (60’) Integration (30’) General (30’)
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7 Dec 2007 End-cap Closeout Review 3 Stephen Haywood Past Reviews Support Structure Contract7 Sep 2004 Disc Assembly27 Jun 2005 Thermal Enclosures22 Sep 2006
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7 Dec 2007 End-cap Closeout Review 4 Stephen Haywood Support Structure Contract
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7 Dec 2007 End-cap Closeout Review 5 Stephen Haywood Problems Unforeseen problems led to delays and more resources. Organising the contract through CERN proved difficult. Two major failures in FWT of flat Panels associated with Cyanate Esther – switch to FM73U film adhesive. Serious problems placing Disk Fixation holes in Support Cylinder; required 6 man-months of RAL effort to rectify. Inappropriate use of 3D models by contractor. Contractual problems with “build to print” design concerning responsibilities. We were poorly prepared to accept components (expected more from Contractor; needs to be specified) – needed longer than 3 months. Metrology can be much harder than envisaged ! Need greater clarity in who pays for what, including Tooling and excess Materials.
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7 Dec 2007 End-cap Closeout Review 6 Stephen Haywood Successes Probably correct not to impose penalties. Load-test and Fit-check at company.
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7 Dec 2007 End-cap Closeout Review 7 Stephen Haywood Disks
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7 Dec 2007 End-cap Closeout Review 8 Stephen Haywood Issues More Engineering effort should be put into Manufacturing processes Assembly Testing Key design criteria should include Robustness – physical & ESD damage Serviceability, including Repair Scenarios Secondary physics requirements should not compromise the engineering principles. Physicists’ requests should be questioned if they have significant cost/time/design implications.
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7 Dec 2007 End-cap Closeout Review 9 Stephen Haywood Companies should be given QA requirements and acceptance criteria. Regular checks should be made of series of components and care should be taken to anticipate needs for raw materials. Prototyping consumes many more raw materials than might be expected. Need more resources than expected ! (See later)
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7 Dec 2007 End-cap Closeout Review 10 Stephen Haywood Thermal Enclosure
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7 Dec 2007 End-cap Closeout Review 11 Stephen Haywood Issues Is a TE needed? What is its role? (Thermal, Gas, Moisture, G&S) Could a single TE be used? Commonality between Barrel & End-cap RAL avoid taking on too much work Do not underestimate work/time/money, especially for trivial things which are “just a …” Ensure good connection with other aspects of project Think abut G&S earlier on Consider working with CTS/Lola Sound out companies before tendering; engage in R&D Consider acceptance criteria in advance Insist on sensible envelopes Avoid active cooling Cu foil is much more flexible for G&S
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7 Dec 2007 End-cap Closeout Review 12 Stephen Haywood From Pippa The hand over of the OTE to Valencia seemed to go smoothly, but the ITE at CERN seemed to be almost too difficult (mea culpa).
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7 Dec 2007 End-cap Closeout Review 13 Stephen Haywood Completion Jeff Bizzell – Heater Wiring Jason Tarrant – Cooling Jason Tarrant – Documentation: SCT End-cap Documents & Drawings – ATL-IS-AN-0009 Abstract This document is a guide to the many documents and drawings relating to the design of the SCT End-cap. All the documents and drawings in this document are those created by staff of the Science and Technology Facilities Council (STFC) in the UK. This document can be used to locate any relevant information on any part of the SCT End-cap that was produced by STFC. Grounding Drawings G&S Parts TD-1011-598 (ATLISES_0095) is the GRP Front Support cover assembly, this calls all piece parts required. TD-1011-161 to 164 (ATLISES_0101 to 0104) are the 4 sections of Cu-polyimide Support Cylinder ground sheet. Documents ATL-IS-EN-0014 ATLAS SCT End-cap Grounding and Shielding, Engineering Implementation
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7 Dec 2007 End-cap Closeout Review 14 Stephen Haywood This Review Questions: What have we learnt ? Includes good lessons; Managerial & Technical What could be done better or differently ? What might we want to take forward for the future ? & Celebration/Thank-you !
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7 Dec 2007 End-cap Closeout Review 15 Stephen Haywood Support Structure
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7 Dec 2007 End-cap Closeout Review 16 Stephen Haywood
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7 Dec 2007 End-cap Closeout Review 17 Stephen Haywood Preparatory work: Prototyping … use of Contractors? FEA Design of Support Structure: Was the concept of a Cylinder and Panels better than a space frame? Materials & Construction Techniques: CFRP, Cyanate-Esther adhesives, Korex Edge sealing Testing Support Cylinder bonding Was RS4 CE film really OK? Unable to undertake FWT test Contract: Should Support Structures and Disks have been in single Contract, ensuring good fit?
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7 Dec 2007 End-cap Closeout Review 18 Stephen Haywood From Patrick The problem was that PCI was not setup to machine cylinders within the specifications. My experience with the disks was that PCI have made excellent quality disks, but even machining the outer and inner diameter was hard for them. Next time it is better to use PCI or any other composite company where they are good in: making composite structures, and find the right company for machining the parts if high tolerances are required. This was done for the barrel cylinders. The mistakes in the machining have caused several problems and confusions throughout the project. At the end there was no alternative than to accept, but everything became more difficult: measurements and supports that did not fit and needed modifications Edge sealing of the composite structures: This should have been done better, at least for the wings. We found several Thermal Enclosure leaks through these aluminium foil closures, and probably still we have leaks through these.
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7 Dec 2007 End-cap Closeout Review 19 Stephen Haywood Services
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7 Dec 2007 End-cap Closeout Review 20 Stephen Haywood STFT
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7 Dec 2007 End-cap Closeout Review 21 Stephen Haywood
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7 Dec 2007 End-cap Closeout Review 22 Stephen Haywood PPF1
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7 Dec 2007 End-cap Closeout Review 23 Stephen Haywood Services Cylinder Radial Cryostat (Cooling ) LMT Opto DCS FSI Routing & lengths Caused a lot of worry for JT & TW Did we get it right (except for Heaters) Physical routing of Heater Pad wires Bends Clips Grounding LMT’s: Al Cu
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7 Dec 2007 End-cap Closeout Review 24 Stephen Haywood From Pippa I worry a lot about the mixture of metals we've ended up with, and the problems we had swapping from aluminium to copper C-seals. The cooling layout has been the most recent headache, since everything had to be redesigned to relocate the heaters. We are fortunate that the C-wheels are not there, otherwise there's no way we'd have fitted everything in. We have had the problems of dealing with overlength of a lot of the services, but thankfully nearly everything has been long enough. There are just a few heater pad cables that need extensions, due to a design change not getting propagated through. The routing of cables to PPF1 worked really smoothly for the end cap, and benefitted a lot from adequate prototyping being done in advance. We had a few issues with optimising the way the grounds were brought together at the clamp, but all the horrible complications of different strip back lengths just worked. Dealing with the fibres as they came off the end cap was also rather easier than for the barrel.
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7 Dec 2007 End-cap Closeout Review 25 Stephen Haywood And of course the evaporative cooling... more extensive and realistic testing before hand might have found the problems with the control thermocouples with more lead time. This still wouldn't have addressed the unreliability of the heaters and the short to ground.
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7 Dec 2007 End-cap Closeout Review 26 Stephen Haywood STFT Construction: Foam & glue CFRP Accessibility (Sealing) (G&S)
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7 Dec 2007 End-cap Closeout Review 27 Stephen Haywood From Patrick What I can recall is that the STFT delivered to Nikhef was of very bad quality. The slots had to be re- machined and repainted with araldite. Also a mistake was made with rotational and mirror symmetry, which had to be fixed in situ. I also think NOW that the parts should be been made much more precise to make everything fit much better. At the end most of the following parts needed adjustments to make them fit.
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7 Dec 2007 End-cap Closeout Review 28 Stephen Haywood Cable Trays Radial Cryostat Complexity Time (Design & Assembly) & Cost Material Assembly
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7 Dec 2007 End-cap Closeout Review 29 Stephen Haywood From Patrick The CCT worked very well as well, except the Ribbon Guides which fitted very difficult on the tabs. Especially at the top it took sometimes more than 1 hour to mount one!! Too reach too far inside and only one hand available. Mounting the RCT cover is also difficult and dangerous with the too long LMT's and R/O ribbons. Has to fit on too many holes and screws. Need about 4 people in a too small area.
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7 Dec 2007 End-cap Closeout Review 30 Stephen Haywood PPF1 Cooling LMT Opto DCS FSI Accessibility Interaction with other detectors
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7 Dec 2007 End-cap Closeout Review 31 Stephen Haywood From Patrick The PPF1 design did not work out very well in the beginning, also because Jason was too busy with the HEX redesign. Too late and too many problems. At the end all is working, but could have been a lot better. We should have had proper protection taken into account during the assembly. The electrical PPF1 were too fragile. In ATLAS there is very little respect for somebody else his parts. People leaning against or on PPF1's to reach somewhere. We have really seen non SCT people abusing our PPF1's. Of course this caused many faults, and damages. Also the Cooling PPF1's are not very well supported. With making the Serto connections too much force is needed and move around. One patch panel has M3 and the other M4 screws, very annoying.
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7 Dec 2007 End-cap Closeout Review 32 Stephen Haywood From Patrick The Type II cable clamp should have been wider closing the PPF1 box. This would prevent dirt getting into the box and solve problems we had with routing the R/O ribbons and LMT cooling pipes. LMT cooling should have had a proper patch panel at the ECex1 connector. The pipes coming of the flange were not properly positioned and too stiff to reroute them. The whole installation and connection testing of LMT's went rather well. The R/O ribbons below the LMT's should be changed for next time. We had to disconnect & connect R/O ribbons several times when LMT's were already connected. This was rather risky with violating all the rules about bend radii for optical ribbons. The Cu/Kapton foils caused us a lot shorts etc. Next time some risk analysis / review should be done for PPF1's, and the person designing should be expecting the worst.
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7 Dec 2007 End-cap Closeout Review 33 Stephen Haywood From Pippa I'd also emphasise the importance of prototyping and system testing, with as close to final parts as possible. A few examples: There was a genuine effort to prototype barrel PPB1, but the final cables were stiffer, and it was a real problem to fit 6 of them across the width available. We had to modify the PPB1 brackets on the fly, even though they were partly glued to the cryostat wall, giving few options. For the end caps, we tried out the real cable in the clamp ahead of time, and were able to redesign it in a calm way, before the cable installation in the pit. There has been lots of system testing of modules, but in the last round of power supply firmware updates, there were changes made which were OK with shorter test cables, but failed to work when combined with long cables and PP3.
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7 Dec 2007 End-cap Closeout Review 34 Stephen Haywood Cooling Use of CuNi X 0 Bending Connectors Were we right to design our own? Accessibility of Connectors Flexibility for connection HEX Design Communications (CERN, RAL, QMW) Manufacture Soldering problems Tony Feedback
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7 Dec 2007 End-cap Closeout Review 35 Stephen Haywood Assembly Sealing Use of Foils & Membranes (Cu-Polyimide) Adhesives Araldite 2011 Techsil Templflex
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7 Dec 2007 End-cap Closeout Review 36 Stephen Haywood From Patrick Parts received at CERN: Most of the parts we received at CERN did not fit and needed modifications. The last known are the metal N2 pipes which did not fit into the Elbow adapters. We had to re-machine all the pipe ends to make everything fit. Another example are holes in the Heater Pad CCT with were we have 7.5mm holes while M3 screws needed to be used. I think at the end we spend a couple of man years modifying parts here at CERN. Parts we received at CERN for an assembly we often received in different batches. We did not have a good system at CERN to receive and storage parts so often parts were lost for some time. Also due to time pressure, the parts were usually not taken out of there boxes until we needed them and then we found assemblies not complete or parts would not fit, causing the next crises. Often parts we received still needed some way of assembly: for example soldering of some copper pipes for the N2 system. This would have been a lot easier for us if these had already been soldered and there are several other issues where this was the case.
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7 Dec 2007 End-cap Closeout Review 37 Stephen Haywood From Patrick The SCT had a particular problem that all most all of our manpower at CERN was travelling. If parts are shipped to CERN these should be shipped complete, assembled and checked before shipping. Do not ask people at CERN to fill in the blanks. If you for what ever reason want to ship parts to CERN not assembled also deliver the right manpower to prepare the parts at CERN as soon as they arrive. We should have invested from day 1 much more in storage and cupboards at CERN and should have given some sort of priority to checking parts as soon as they arrive. We were never very good in checking and approving drawings, which caused a lot of problems.
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7 Dec 2007 End-cap Closeout Review 38 Stephen Haywood From Patrick During the assembly of the EC the services TPPF1's should have been positioned at there final location and moved inward for transport only. The too long LMT's and ribbons caused several problems and cables are now under tension, which may cause us some problems in the future. The HEX assemblies should have been part of the assembly and testing in NIKHEF/Liverpool or at least in SR1. Only simple pipe connections should be allowed next time during installation. I know this has a big history with Marco, but next time we should not allow this to happen again. The Thermal enclosure should be sealed in SR1. This we should have never allowed to happen.
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7 Dec 2007 End-cap Closeout Review 39 Stephen Haywood From Pippa I think that having a design that didn't allow closing of the thermal enclosure in SR1 was a big mistake. I do realise that this may have been the only solution consistent with the envelopes originally imposed. But the detector has been in the pit for months now without being finally closed at the end, which is risky. It's also an interim problem for installation and testing, in that we can't run cooling at all until the entire plumbing installation is finished. The space constraints also pushed us to use lots of specially designed non- standard connections, which was tricky, and in the end forced some things with the installation sequence that were a problem for the schedule. Techsil... pah!
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7 Dec 2007 End-cap Closeout Review 40 Stephen Haywood Grounding & Shielding
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7 Dec 2007 End-cap Closeout Review 41 Stephen Haywood Schematic
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7 Dec 2007 End-cap Closeout Review 42 Stephen Haywood Design Retrospective Ground all metallic parts Groundsheet on Support Cylinder Membranes Tabs STFT Small foils Connections Soldering Silver-loaded epoxy Finger-stock Quench forces
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7 Dec 2007 End-cap Closeout Review 43 Stephen Haywood From Patrick Using the Segmented Plate as our grounding ring was a very bad idea. because also others use these plates to mount parts this has caused a lot of problems. If we would get a short now it can be a million things and we cannot systematically disconnect parts any more to find the short, which is a big concern. So lets hope this does not happen!
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7 Dec 2007 End-cap Closeout Review 44 Stephen Haywood Integration
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7 Dec 2007 End-cap Closeout Review 45 Stephen Haywood Fit Rear Support Panel (Wing) Transfer to Cantilever Stand (CLS) Transfer loads to CLS with Rear Support Yoke and PPF1 & TPP Support Yoke Insert ITE, using ITE Carriage Fit Link Plate Add OTE, using OTE Mounting Frame Insert into TRT Add Front Support Panel (Wing) with Bridge Support System Add Mechanisms and support from Rails Also PPF1 & TPP to TRT Arms Shim Adjustment StandsNot needed? Transportation Lock System Services Support Ring
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7 Dec 2007 End-cap Closeout Review 46 Stephen Haywood Issues Did we anticipate all requirements? (Eg. Split Front Support was anticipated right from beginning) Was Tooling optimal and fit-for-purpose?
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7 Dec 2007 End-cap Closeout Review 47 Stephen Haywood From Patrick Orange cantilever stand: Wrong paint was used. When using alcohol to clean the paint was removed, so we were not really able to properly clean. The "front transfer plates" were not very flat ~ 5mm. I still believe that this is why EC-C. For EC-C this plate was mounted and stressed several parts and when removed, changed something on the EC. I still believe that this is one of the causes why we have bigger leaks in the thermal enclosure than on EC-A. On Side A the "front transfer plate" was re-worked and made flat to be well within 0.5mm. Integration: I have never liked the way the EC was supported on the cantilever stand. Also the transfer from the assembly frame to the cantilever stand and from the cantilever stand to the EC trolley we should do differently next time. The EC should have been supported in a kinematic way. With the tooling provided we did not have any precise control over what we were doing. Moving the EC onto the EC trolley we ended up 2mm away from what we aimed and had a twist. At the end this was accepted as more or less a good position. For Side A we had to make special to lift the EC in the frame and reposition the EC at the front. It was too difficult and time consuming to make tooling to reposition the EC at the rear. At the end everything turned out to be ok, but it wasn't easy.
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7 Dec 2007 End-cap Closeout Review 48 Stephen Haywood From Patrick A private comment on building detectors. You may not want to use this or word it differently: A lot of problems with building the EC's was on the manpower involved and specifically on EC-C. The detector should be built by technicians and not by physicists or engineers. I think most of the time people not "qualified" were working on the EC. When doing these difficult projects people with the right skills are absolutely needed. I also see this general change in institutes where mechanical departments are reduced or even cancelled and I think this is very bad. We need the best technicians to make the best detectors: i.e. fix all the problems that we cause. Also engineers should be much more involved in building detectors, especially the parts that are designed. If this does not happen the engineer will not learn from his mistakes. One annoying thing I had with EC-C is that people were always too much in a hurry. At the end this resulted in much more problems and delays. I also believe that EC-C was shipped too early too CERN. People travelling to CERN are not very efficient in working hours and EC-C had enough problems which could have been solved in Liverpool. This would have saved a lot of time.
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7 Dec 2007 End-cap Closeout Review 49 Stephen Haywood From Patrick The trap we always fall into is accepting parts that we know are wrong, but due to time pressure we accept them. This causes many more problems, than solving the original problem.
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7 Dec 2007 End-cap Closeout Review 50 Stephen Haywood General Interfaces & Communication CERN Nikhef Valencia Ned for G&S RAL Organisation Proj Man: Debbie Stephen Dept: Debbie Eddie Mike Senior Engineer to replace Debbie? Additional Engineer to support Jason?
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7 Dec 2007 End-cap Closeout Review 51 Stephen Haywood Scheduling Most things took longer than expected – never enough time/people Use of MS Project Did we get level of detail right? Need to schedule time for Admin Holidays Contingency Difficulty of individuals undertaking multiple parallel tasks Time for Prototyping Should we have been more involved at CERN, especially post Integration? Note: Jeff is still helping with wiring.
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7 Dec 2007 End-cap Closeout Review 52 Stephen Haywood Manpower Never enough Would have benefitted from separate Manager & Engineer Eg. Difficult to manage contractors and do work Importance of getting good people Avoid loosing key people until work really finished (Eg. Ian) If Manpower “envelope” is constant, front-load effort to allow for problems Not ideal for Dept planning; cost of keeping a large team in light of delays and changes
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7 Dec 2007 End-cap Closeout Review 53 Stephen Haywood RAL Support Workshops Metrology SSTD Workshop (John Spencer) Contractors: Designers (John, Steve, Alan, Tommy) Technicians (Cooling Lab) Lab space: Clean Rooms Needed much more space than anticpated Cooling Lab R12 Metrology Stuart’s area
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7 Dec 2007 End-cap Closeout Review 54 Stephen Haywood Cost Consistently underestimated by factors of 2-3* Initial inquiries gave false expectations or expected savings did not materialise “Cheap” materials turned out to be less cheap, eg. Airex Bits and bobs can add up Cost of effort in labour-intensive work adds to total cost (Cooling pipes, Stiffeners, Membranes) * The exception was the Support Structures which cost 0.6 M$, while we feared they could be >>1 M$
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7 Dec 2007 End-cap Closeout Review 55 Stephen Haywood Financial Control I struggled to follow costs in Famis Identification of expenditure in Famis often obscure; lots of junk Would have helped to subdivide FK36000 – I could not understand how much we had spent on Discs, TE etc Engineers spent money without communicating (did try to control this several times) Bits and bobs add up I failed to understand budget and contingencies (from Janet) Janet seemed to understand the bottom line and have significant contingencies Despite my lack of control, it seems miraculous there was not a net overspend on the ATLAS Eng In future, prepare very carefully before embarking on project and consider parallel system (personal spreadsheets) to track
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7 Dec 2007 End-cap Closeout Review 56 Stephen Haywood Expenditure ExpenditureBudget Discs 416 353 Structures [1] 341 TE [2] 41 86 Services 185 57 Ass/Integration[3] 50 50 Total1033 [1] UK paid 20% ie £61k of £317k PCI Contract [2] We only supplied parts and paid for some tooling, we did not build OTEs or ITEs or Rear TE Pads [3] Estimates – not updated, but probably in budget Uncertainty due to difficulty of assessing and I have not revisited … ultimately bottom line from Famis
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7 Dec 2007 End-cap Closeout Review 57 Stephen Haywood From Disk Review: One needs far greater resources (money, time, effort) than is often guessed (take first estimate and increase by factor of 2 to 3 ( ?). What is expected to be trivial at an early stage in the design often can prove more complicated when considered towards then end of the design phase, when there may be many constraints. From Patrick: For time, money and manpower you should next time take into account at least a factor 2.
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7 Dec 2007 End-cap Closeout Review 58 Stephen Haywood Other Things Documentation Pro-E & Intralink EDMS CDD Reviews Internal CERN (FDR, PRR, regular meetings)
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7 Dec 2007 End-cap Closeout Review 59 Stephen Haywood From Patrick At the end I am satisfied with what we have achieved, but we have certainly not chosen the easiest way. The result could have been better if more qualified people (technicians) would have been based at CERN for the last two years. The last two years have been difficult for people travelling a lot to CERN, especially for their personal lives. Next time an attempt should be made to get more people based at CERN.
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7 Dec 2007 End-cap Closeout Review 60 Stephen Haywood ATLAS SCT EC Eng Team @ RAL WorkshopTDPPD Alan AustinPaul BarclayRichard Apsimon Geoff BurtonSteve ButterworthLewis Batchelor Eamonn CapocciMike Curtis-RousJeff Bizzell Colin DabinettPeter FordStephen Haywood Mike HarrisDebbie GreenfieldRichard Holt Cyril LocketJohn MathesonMike Tyndel Graham RolfeCraig McWaters Chris Nelson John Noviss Brian Smith Jason Tarrant Steve Temple Ian Wilmut
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7 Dec 2007 End-cap Closeout Review 61 Stephen Haywood Well done & Thank you … the drinks are on me
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