Feedthrough Meeting 25/03/98 present: P. Birney, M. Dobbs, M. Fincke-Keeler, T. Hodges, R. Keeler, R. Langstaff, M. Lefebvre, P. Poffenberger - Status of Pin Carrier Order The Glasseal order was placed Feb 10th. The order for Victoria comprises 10 units of 448 pin carriers @ US$1455 each 10 units of 512 pin carriers @ US$1621 each The delivery time is 13-14 weeks. Glasseal quotes for 500 pins are very interesting: 500 units of 448 pin carriers @ US$593 each 500 units of 512 pin carriers @ US$659 each The PCT order was placed Feb 24th 10 units of 448 pin carriers @ US$3872.02 each 10 units of 512 pin carriers @ US$3960.84 each The quote for a quantity of 500 is reasonable: 500 units of 448 pin carriers @ US$1997.05 each 500 units of 512 pin carriers @ US$2026.73 each - Status of Model The mechanical part of the model is done. Paul and Margret to work on the production of dummy cables. 22 gauge Cu wire will be used for the pigtails, plastic sheets for the vacuum cables. Paul and Margret will use the model to prepare a first draft of a list of procedures for assembly and tests of the feedthroughs. Margret will document the coordinate system and exact orientation of the various feedthrough components. - Vacuum Cable Status The low voltage currents estimates from MPI have gone up cpmpared to the numbers Terry based his earlier analysis on. Some traces now need to hold over 700 mA. Margret will communicate the new currents to Terry for thermal analysis. Margret points out that the stress induced on the web from stiplines with large and low current needs to be investigated. It was stated during the last LAr week that each monitoring line will carry less than 10 mA. Terry agreed to compute the temperature rise for the normal signal strip line for various currents (below say 150 mA). Margret reported on the status of the vacuum cable project. The strips have been produced by Strataflex, and have been sent to AMP for crimping. The crimping machine at AMP cannot crimp the sockets at the right depth position on the printed circuit board: attempting to mount the connector with improperly crimped sockets leads to an overstretched ground clip, and potentially poor ground contact quality. Strataflex has agreed to trim the strips and the crimp the sockets. AMP has been asked to send the strips to Strataflex. Pierre Imbert pointed out that crimping can cause tear of the Kapton upon temperature cycling. He would favour soldering only. Margret has identified a tin alloy known to work for our cryogenics use. Margret pointed out that we should verify the actual impedance and with of the striplines. There is a question as to why the BNL striplines are wider than the specified width (200 microns). Richard mentions that we could consider providing Strataflex with the means to measure the impedance of the striplines. The AMP housing used by BNL are known not to be ideal for our cryogenics use, but will be used for the prototypes. The ATI housing made of ULTEM is favoured by Pierre Imbert and Ernie. Michel to discuss with Gerald the possibility to increase Ernie's time on the project. - Refrigerator Project Status Paul reported on the refrigerator project status. All material received, and all drawings finalized. Cold head tests starting. Pof to look into the state of the temperature probe order. - Leak Test Setup Status Paul reported on the status of the leak test setup. The warm section is still under vacuum held by the ion pump, pressure slowly decreasing. The two pressure gauges are in operation, and track each other. Matt has produced and interface to LabView for the pressure gauges; LabView can read and record the pressures at a programmable frequency, than can be varied at any time. Paul is now tackling the cold section. The material is on order, the vessel to be machined outside of UVic because of its size. The size of the 2 pigtail buckets needs to be established. Paul and Richard will review the number of serial ports needed. We need to look into the data loging capabilities of the RGA control software. - Bellows, Flanges, Funnels Still waiting for Jason for an update on the bellows and warm flange drawings. Michel to investigate. Roy presented a drawing showing the space available between the cold and warm vessel, showing enough room for the operation of an orbital cutter and welder. Roy presented a possible by metallic junction extension profile that would stop metal chips from falling in the cryostat or the cables upon feedthrough assembly removal. - Plans for Prototype Construction and Tests Assuming that the pin carriers arrive mid June, the bellows and flanges should be ordered mid April. We agreed to purchase 3 bellows, 4 warm flanges and 4 cold flanges. Quotes should also be obtained for orders of 60 and 125 parts. More thoughs has to be put into our plans for testing the prototypes and pin carriers. Possible ideas: - visual inspections - leak testing - temperature cycling --> leak testing - welding of pin carriers in flanges --> deflections --> leak tests --> cold flange cooling, leak tests - repeated temperature cycling on some pin carriers --> leak tests We could use 12 glass pin carriers and 4 ceramics welded in flanges. Roy points that we also could put 2 types of pin carriers on one flange and do hard test on the lot. We need to come to an agreed plan, to be discussed also with Dave Rahm, before we receive the pin carriers. - ATLAS Meetings and Other Important Dates - Mar 29 - Apr 04 : ATLAS Physics workshop, Grenoble - May 04 - May 10 : LAr week - Jun 08 - Jun 12 : ATLAS week - Jul 06 - Jul 10 : LAr week - Jul 23 - Jul 29 : ICHEP98 "Rochester Conference", TRIUMF - Sep 04 - Sep 18 : ATLAS week - Sep 21 - Sep 26 : LAr week - Nov 12 - Nov 18 : LAr week - Nov 16 - Nov 20 : ATLAS week