Minutes of the August 5
Tracker Meeting
1) Latest tray status and
test results
Andrea had sent some results
on the Tower-A bottom tray static test.
Chris expressed concern about the torque loss in the static test. He emphasized to be sure to torque stripe
the nuts in Tower A before the vibration test.
Andrea said that the torque
loss did not exceed the limits defined in the procedure. The results were essentially equivalent to
those of the EM tower. He will study
the data more and make a more careful comparison. At the end of the test there was a problem with removing one stud
on a corner flexure (+y-x) which was stuck to the cones. It was a non-coated stud. Arthur said that at the end of the month he
will provide new static test hardware.
Luca Baldini is at G&A
testing more trays that are wire bonded, but no results were yet available.
Riccardo reported that only
the top tray remains to be vibe tested and that will be done tomorrow). All vibration tests were successful. The Kapton-reworked trays passed the T/V
test in Rome and are now at G&A.
All remaining tray panels are going to Pisa tonight and to Rome
tomorrow. The top tray will fly to Rome
tomorrow, and all the T/V tests will be completed before the end of the weekend. Monday G&A will have all the trays.
2) Tower (and tray) survival
test temperature requirement
Robert reported that working
the request to lower the test temperature is very difficult this week because
the thermal engineers are all on vacation.
He had talked to Dick Horn about the issue, and Dick agreed that a 5
degree reduction (from 50C to 45C) could be contemplated and probably could
eventually be agreed upon. Nevertheless
there was no way to finalize such a change in time for the weekend testing. Anyway, Sandro said that the Tower-A tests
will go forward at 55 degrees.
3) Transportation
requirements for trays
Robert said he had talked to
Martin about this. Martin will have
John Ku do some analysis. He needed,
however, the drawings of the tray box and the handles that support the tray
(Emilio sent those and they were forwarded to Martin).
4) SLAC deliveries for Tower
A
Sandro and Emilio requested
that SLAC postpone the shipping by about 1 week, because they will not be able
to retrieve items from the airport until August 23.
-
Lifting
fixture: ready to ship
-
TEM/PS
for T/V testing: there was a problem with the cable bias, but it turned out
that the cable jumper was bad. Hiro will continue working this issue to get the
EGSE ready to ship to Italy.
-
Inner
container and cable holding plate: proof testing will start tomorrow and
require a couple of days. We need to
add holes to the top for attachment of the data logger. Chris expressed concerned about the weight
of the logger and suggested it would be better for it to be closer to the tower/Grid
interface. Chris wants a copy of the
container drawings.
-
Outer
container and data logger: the logger is ordered; a PR is out for the container
and the spec is out for review. There
was some concern about the strength of the fasteners between the container and
pallet. Will they be strong enough if
only the pallet is strapped to the truck or airplane? Nanda thought we need attach points on the container,
particularly for the airplane.
-
Fasteners
o
M2.5,
100 degree: Jeff said these were sent already
o
M4
6mm: under inspection at SLAC
-
I/F
hardware: Arthur will hand carry all
this stuff to Pisa
o
M5
nuts: in hand
o
Inner
and outer cones: in hand
o
Studs:
enough are in hand for Tower A, but Arthur prefers to use studs from a new
order shortly to arrive. They have a looser
thread class and should be easier to work with.
o
Hex
bushings: getting coated
o
Shims:
still need to be plated
-
Alignment
tools: Peter said that Pisa should have all of them needed for Tower A. He has a chart to email to Pisa. He will in any case send some replacement
and backup tools, probably by hand carry
-
Digital
torque meter: ready to ship
-
Cable
bending tool and cable installation mockup, with cable test samples: Arthur
said that the tools should be at SLAC by now.
The mockup can be made in a couple days; its drawings are almost ready.
-
1.5in
tooling balls: Arthur will have 10 in the next day or so
-
Reflector
ball nests and magnets: nests are in metrology; magnets are on order---Jeff needs
to expedite them
-
Solithane:
ready to ship; Jeff needs to get it re-cert’ed however
-
Locktite
401: ready to ship
-
Tower
baseplate assembly: Jeff will check with purchasing and Humboldt. There was a small amount of machining still to
be done, but the vendor needs SLAC approval for supplemental funding; Arthur
said he also wants some extra square nuts
-
cable
brackets and clips: these are not done machining yet. There will be a spare bracket for tower A plus spare clips. Robert
recommended using the spare bracket to test the assembly procedure on the EM
tower. Robert talk to Martin about grounding of the brackets.
5) Other deliveries
-
MCMs:
a set of 31 is ready to ship, as soon as QA give the go-ahead.
-
Bias
circuits: 144 bias circuit ready to ship. Robert will talk to Jerry about
future delivery rates from Parlex.
Plyform is anxious to have assurance of adequate supplies when mass
production of trays begins in September.
-
Bottom
tray honeycomb: they have been sitting at SLAC for at least a month. This week QA is checking them over, and then
they will be ready to ship to Pisa.
6) Tower assembly
preparations
-
Schedule:
INFN is still on schedule for an August 25 PRR and August 26 start of tower
assembly. In fact, the trays are going
to G&A 1 day in advance of the plan.
-
Procedure:
draft #3 is out for review and comments.
-
Test
procedure draft: Luca Baldini will sent the latest draft to Hiro.
-
Assembly
drawings are out for review: they look good to Emilio. He said that he has some suggestions for
additional dimension lines and another view to send to Martin.
-
Alignment
plan/procedure status: a new plan draft was circulated at SLAC last week. The latest plan needs to go to Italy to be
sure that their procedures are in agreement.
-
Travel:
Robert and Arthur arrive August 24 in the evening.
-
At
the Tracker meeting August 19 we will review the status of hardware and
documentation. An internal Tracker
preliminary production readiness review will take place by telecon on August
23. The final PRR will be August 25.