STATUS OF THE MEG CRYOSTAT Construction status Schedule ____________________________________________________________ 04/Agust/06 F. Raffaelli, L. Delfrate

CONSTRUCTION STATUS The vacuum vessel is going to be tested today (04/August/2006). The vacuum window was tested last week. The cold window is going to be tested after the 20 th of August. The Cold vessel is ready for installing the cold window, It has everything (pre-cooling circuit flanges etc). The thin foil of the cold window is going to be welded next week The Honeycomb panel is going to be delivered to SIMIC the 12 th of August. After the 20 th of August the cold window is going to be tested and the last week of August the cold vessel will be tested. The goal is to have the two vessels ready for assembly at the beginning of September. ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

CONSTRUCTION STATUS We try to investigate the time nodded for the rest of the operations. Simic is agreed with the following planning.. ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

CONSTRUCTION STATUS Planning 14166_7 (July 21, 2006) July Pressure test of a warm window in the test box (performed on 20 July). Second warm window construction. Cold window mould construction July Warm window welding to the warm vessel. Cold window mould machining. 31 July Delivery by INFN of the honeycomb panel at SIMIC’s workshop 1-11 August Leak tests of the warm vessel. Cold window welding to the test box. Pressure/leak tests of a cold window in a test box with the honeycomb. Second cold window shaping. ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

CONSTRUCTION STATUS August SIMIC CLOSED 21 August – 4 September Cold window Welding to the cold vessel. Auxiliary internal structure installation (hold - to verify). Pressure/leak tests of the cold vessel. Cold vessel drying. Helicoflex Helium test. Internal structure positioning (hold - to verify) September Temperature sensors installation. Super-insulation installation. Assembly of warm and cold vessel. ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

CONSTRUCTION STATUS September Welding chimneys Helium test. 02 – 06 October Cold vessel polishing. Cold vessel cleaning and drying October Preparation of Cryogenic test Cryogenic test Leak test again. Shipping. ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

The windows now are welded on the body directly. A leak test is performed on this weld on the body. This design implies modification of the honeycomb the production of some additional pieces. ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

How can we do to solve the problems on the Honeycomb. We are changing a material to be able to avoid a transition between the high module fiber to low module fiber in the edge and replacing the filler material non the edges. Right now we have six plies of fiber on each side +45/-45/0/-45/+45 for a total of thickness on.7 mm. In the edge we need to (inter laminar method) a low module fiber to be able to make the bend and a filler material epoxy with glass micro sphere is inserted. The thickness of the honeycomb is 19 mm and the density is 50 Kg/m 3. We are going to use a thicker honeycomb 26.4 mm with the same density to increase the inertia and a fabric fiber with intermediate module will be used to avoid the transition. So an internal reinforcement will be made at the edges. After we contacted the Excel experts We change the adhesive proposed by Playform that was not usable at the Nitrogen temperature ____________________________________________________________ 04/August/06 F. Raffaelli, L. Delfrate

____________________________________________________________ 04/Agust/06 F. Raffaelli, L. Delfrate Conclusions Cryostat construction: The delivery of the cryostat is now at the end of October. The schedule proposed is in agreement with the company. We are doing our best to push the company.