Minutes of feedthrough meeting of March 13, 2000. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Present: MGF, GV, PB, Pof, MLenc, RL, JL, RKK, CJO *) Milestones: - The `pigtail pull' test was done last week, with the ati connector of a pigtail connected to a pincarrier and the cable pulled using a hydrolic jack. A spring scale was used to montor the force of the pull. The test was done twice, once with the cable offset so as to mimic the case of a cable furthest from the lower funnel tube, and once with no offset. The continuity of each line of the cable was monitored with the Cirris tester running in continuous mode, so that any intermittent faults would be flagged as a failure. For both trials, a total force of 1000 Newtons was applied, with no faults observed. - The pincarrier pin temperature vs current test was done, with the bottom half of the pincarrier in vacuum and the top half at atmosphere. Temperature monitoring was done with a thermocouple attached to to one of the pins on the top half. Equalibrium temperatures vs current are summarized here: current (amps) temperature (C) ^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^ 0.00 24 0.51 24.5 0.74 25 1.05 26 1.43 29 1.92 33 2.25 36 2.51 39 2.86 44 3.19 48 3.63 57 3.85 61 Note that the maximum current of 3.85 amps tested here is higher than the maxium current of 3.27 amps tried during the LV tests with Horst Brettel. *) Leak checker / cold test station issues - The RGA was tried in He leak check mode. The 10^-8 calibrated leak could be seen easily, and so probably could a leak somewhere in the 10^-9 range. The 10^-10 calibrated leak was *not* observable. Although not as sensitive as the He leak checker, the RGA is probably still sensitive enough to work as a backup when the He leak checker is not available. Another issue however is that the RGA requires a much lower pressure before it can be used, so the turnaround for testing items such as pincarriers is much slower (~20 minutes). - The electronics shop pulled and reseated the mico-processor board and all associated connections with the hope that this might cure the apparent mico-processor errors which occur on startup. If the mico-processor is found to be fawlty with an intermittent, we should purchase a spare (US$1095) to have on hand. - A surge protector or power smoother should be used for the He leak checker. - As of today (16 March) the He leak checker has ceased to be operable in a useable fashion, being unable to even perform a self calibration. Arrangements are being made to send it back to California for repair. After consulting with the Balzers Tech Rep in California, it has been decided to send Paul B to the Balzers repair facility to learn how to perform the servicing and repairs at UVIC. Hopefully he will also be able to determine what has been causing the failures. We will also explore the possibility of trading in the present He leak checker for a newer `dry' leak checker. - A calibrated leak in the 10^-9 range should be purchased, and also one additional Nupro valve. - The fawlty full-range gauge was cleaned with alcohol, and is now again. *) We will try the following strategy to keep the lab clean: - Damp wash all table surfaces and floor. - No more use of the chalkboards. - Restrict access from hallway; access only allowed through 021. - Lab coats should be worn when working in machine shop or any other `dirty' area, and removed before entering feedthrough lab. - Install floor mat and foot cleaning brush in 021 adjacent to lab door, and sticky mats just inside feedthrough lab. - Note that PB, GV, and AD should be equipped with steel-toed shoes while working with the flanges. These can be purchase through TRIUMF. *) Still no news from TIS regarding pressure or Charpy tests. *) There is still no reply from Aboud regarding our offer of preproduction pincarriers and special flanges. *) The balance of the Timken steel is expected in two weeks. *) Terry has asked purchasing to check with Glasseal regarding their steel inventory and revised delivery schedule. *) One set of four prototype Shipping / vacuum-test bars, to brace the bellows during shipping and to constrain the bellows from collapse during vacuum tests at CERN will be made at UVIC. The balance, 60 sets of four, will be farmed out to an external shop. *) Electrical test equipment is nearing completion. The impedance measuring device is expected to be completed this week, as is the second amplifier/shaper unit for the mobile cross-talk station. The cross talk measurments done with the Camac setup are more time consuming, so the number of averages taken for each pulse must be optimized to the fewest number for the required resolution. These studies are in progress now. The VI for the impedence setup will also have to be developed, and integrated into the Phred (resistance) and Phreda (contact resistance) tests. *) Terry is working on a FEA for the UVIC design of the ambient flange heater. Initial results indicate that Aluminum design works well, and that thermal grease is required for adequted thermal conduction. A question was brought up whether the heater contacts should be gold plated or tin plated. Mark will contact Christian Zeitnitz at Mainz about this. We will construct a prototype flange heater and operate it continuously at a high level for many months to test for failure. *) Chris Oram will organize an external review of our assembly procedure a few months after production begins. The review will take place at our lab. *) Paul B has written a draft of the cold test procedure, along with a schematic drawing of the cold test station. This will be circulated in the near future. *) Jobs for this week: - Debug and deal with the He leak checker - Develop the TDR VI and continue fine tuning the Camac crosstalk VI. Agenda for next week: ^^^^^^^^^^^^^^^^^^^^^ - Milestones - Leak checker status - FEA analysis - Glasseal delivery schedule - News from TIS - AOB