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The RICH 2 transport story
The RICH 2 mechanics, which includes the superstructure together with the overall magnetic shielding structures and the optomechanics, was moved from building 156 and installed in the experiment in week 46 2005. This was a major landmark for a collaboration which was established in 1999. Due to constraints in time and space, it was at that time decided to assemble the main mechanical parts in 156 and, after careful alignment of the mirror systems, transport it as one unit to the pit. The assembly of the structure started early in 2004 and was followed in late autumn that year by the installation of the two large soft iron shields where the photon detectors will be housed. A clean room was erected around the structure early in 2005 and was followed by the installation and alignment of the spherical and the flat mirror systems. A gas leak test was performed after the two closing windows had been put in place. And nearly 30'000 kilograms of RICH 2 were ready to leave. Although sturdy and big, RICH 2 is delicate with its 96 aligned mirrors. It was therefore imperative that the levelling of the detector could be kept as good as possible and the shocks from acceleration could be minimised throughout the journey. In addition there were questions about damping of vibrations from the engines and the weather. The transport itself was organised by TS/IC group at CERN. They took care of most of the paper work and scheduling of the French police, customs officials, EDF, safety, transport firms, tree choppers and other vital services. The departure time was set for Tuesday 15 November at 18:30, with a second window of opportunity the following Thursday night. Tuesday was a beautiful late autumn day, chilly with no wind. RICH 2 was wrapped, placed on the Omega platform already on the trailer, and strapped down. (The Omega platform is a 50 ton contraption needed to keep the centre of gravity low.) The platform together with RICH 2 had been equipped with accelerometers and level measuring devices. Two persons took place on the trailer to supervise the instruments and to give feedback to two other persons who steered the wheels and the levels of the trailer. On the stroke of 18:30, the convoy started to move out of building 156. Within minutes, all entries and exits to CERN was blocked. The CERN roads are surely not built for a 20 meter long and 100 ton delicate transport. Our roundabouts are narrow and the road planning committees like 90 degree junctions and if they can, will make them 30 degrees the wrong way. By 21:30 the driver(s) had managed to negotiate the real bad parts of the road and we had reached the junction between Rte. Gregory and Rte. Powell. Everything looked perfect and the moon was full. We could see the French police and customs officers ready to open the new gate at 22:00. Then one of the three front wheel axels broke. Limping along, RICH 2 was parked on Rte. Siegbahn. Bottles of N2 was found together with a gas rack and the gas was injected into the vessel in order to keep the humidity below dew point. Wednesday morning started with rain and a bitterly cold and strong northerly wind. RICH 2 was further wrapped and, when the axel was repaired, moved out of the wind tunnel between building 188 and 185. By 21:00 on Thursday, everybody was back and took their assigned places and at 22:00 the gate was opened and RICH 2 started to move towards Rte. de L'Europe. It was another cold, but still, night. It passed under the live 300 kV power lines three times rather uneventful. The power in the 20 kV lines had been switched off and they were manually lifted when RICH 2 crawled underneath. By 6 o'clock Friday morning the trailer was negotiating the last 90 degree bend to enter the surface hall of pit 8. And the hydraulics of one of the four back axels broke. Repaired, it entered with a few centimetres of clearance. But more is not needed. Then there was the lifting off, lifting on, lifting down and driving out. Finally, RICH 2 could be lowered down the shaft, with the canonical few centimetres of clearance to the sides, and was landed skilfully on the platform down in the pit. Saturday saw it doing its final leap onto the bunker. By 7 o'clock in the evening RICH 2 was bolted down in its final position. Despite all the unforeseen delays and mishaps, it looks like that the RICH 2 mechanics is fully intact. The RICH 2 mechanics team is very happy and we promise we will never do it again. What we will do, though, is to thank you all. Thank you for all your support and help throughout the conception, building and readying of this device. We also hope that this detector, when fully operational, will serve physics as it was intended to do. As a special treat for you, we have some pictures to show. G:\Workspaces\d\div_ppe\TA2\LHCb\Optical_lab\Rich2_move\156 to pit8
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