Minutes of Feedthrough Meeting of 3 June 02
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Present: Pof, ML, FH, WW, PB

Milestones:

	- The final electrical tests were completed
	  for ft41.

	- ft43 was cold tested successfully, and the
	  final electrical tests were also completed.

	- ft44 was welded and cold tested successfully.

	- ft45 was cabled and welded.

	- ft46 was cabled.

	- The last of the ambient and cold flanges were
	  welded.  We have sufficient numbers of welded
	  flanges to complete ft54 (the 55th feedthrough)
	  plus one spare each of the ambient flange and
	  cold flange.

*) Pierre Pailler sent this information last week:

	Some news on the End cap C Cryostat test program. 

	The Cryostat has been remounted and turned to the test
	position (axis horizontal) last Thursday.  After
	pumping the insulating vacuum volume we discovered that
	a leak was present, still yesterday, on the cold vessel
	about 10-6 mb.l/s with a pressure of 1.5 bar abs. in
	the cold vessel.  Today after clearing some leaks on
	the Feedthrough chimneys the previous leak or
	background has disappeared. The background measurement
	on the insulating vacuum was between 2 and 3x10-9
	mb.l/s this morning.  We shall continue the leak check
	building up the pressure to 2.7 bar abs. in the cold
	vessel.  The next step will be the cold test; the
	connections will be prepared next week and if nothing
	serious occur we expect to have the Cryostat ready for
	integration of the Feedthroughs by the end of June.

Pierre later wrote to confirm that the endcap cryostat C cold 
vessel leak test at 2.7 bar was completed successfully.

*) Aaron suggested (and everyone agreed) that we restrict ourselves
   to building only the simpler Standard and Special type feedthroughs 
   during the period when most of the crew is in Geneva or on holiday.

*) The ambient flange heater test apparatus has been turned over
   to us for trial heater tests.  We expect to start using it
   this week.  Wendy will be responsible for carrying out and
   documenting the tests.

*) Laurent Serin informed us that Axon is still unable to produce
   the final pigtails with the "standard" micro-D connectors without
   a further sixteen week (minimum) delay:

	The muD connectors received by Axon from ITT canon to
	produce the last T52 and other pigtails are still not the
	ones used up to but with the new insulation.  It seems that
	ITT canon do not want to produce old style connectors, and if
	Axon really insists, they are talking about minimal 16 weeks
	delivery delay which is quite not reasonable for us.  In
	these conditions I believe we should accept to have these
	pigtails equipped with these new muD connectors.  They say
	them to be more radiation resistant and we should as soon as
	possible in parallel to the production test them again
	possible pollution in the Argon.  Making just a small
	computation, the volume of this new material is about 3.5 cm
	x 0.5 cm x 0.5 cm so almost 1 cm cube. I believe that
	typically the number of cable to produce is about 100 so 100
	cm3 to be compared with a Argon volume of 30m3 in one endcap
	so that the proportion is 3e-6=3ppm so that even if these
	connectors had problems of pollution, there is not a very
	large risk of having problems.  
  
	I apologize for all these problems with the end of the
	cable production. Could you let me know if you accept this
	strategy as soon as possible ? 

   From an earlier note, Laurent informed me that there are 10 T47's,
   24 T48's and 30 T52's held up by this problem (although there are
   actually 12 T47's, 29 T48's, 1 T49, and 30 T52's still to be
   delivered to us).  On Michel's suggestion, the question of how to
   proceed will be addressed at a higher level.  Michel has also 
   suggested that if the green light is given to proceed with
   the "new" connectors (as it almost certainly will be) that we
   delay building feedthroughs with those cables having the new
   connectors until the results of the pollution tests are known.
   Unless the pollution tests can be done very soon, this will almost
   certainly delay the building of the last three feedthroughs
   (two Standard and one FCAL).

Agenda for next week
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-Milestones
-Plans for the week
-AOB