RPC production at GT (status and plans)

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RPC production at GT (status and plans)
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Status

• After the IFR meeting in Rome a new version of
  the Production Plan have been proposed to GT
• Main requirements currently included in the P.P.
  are
• Improvements of the infrastructure at GT
• Improvements of the oiling process (new)
• QA/QC procedures and tests during processing
• pre-production test

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Status (cont.)

• Infrastructure at GT
• Assembly shed
• GT have modified the shed where bakelite plates
  are prepared and assembled to ensure an higher
  level of cleanness.
• The assembly area have been isolated from the
  outside by means of a sliding door and a
  controlled entrance have been installed out of
  the shed.
• All products used in this area will be
  controlled and certified (chemical, cloth, tools
  etc..)
• All workers in this area must have clean and
  standard dress plus must wear gloves and hat
• Test station area
• almost ready. All the infrastructures needed
  for the cosmic ray test are in place.

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Status (cont.)

• Oiling system
• the new method foresee a magnetic drive gear
  pump to force the oil-eptane mixture through a
  5µm nylon filter before entering the gap volume.
  The filling time is controlled by varying the
  pump speed while the emptying is controlled by
  the time to bring the oil tank from the ceiling
  to the floor level.
• The Pump waiting for an offer . The main
  difficulty is to find a vendor which have the
  pump in stock.
• Best offer at the moment is a Verden-maag inox
  pump that could be sent at GT the for the end of
  July
• Compatibility between lineseed oil and eptane
  with the Nylon filter must be checked too.

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Status - The corner pieces

• Since the Rome Meeting it have been decided also
  to start to design and make a Corner Piece to
  avoid drilling the gap to insert the gas-inlet
• 30 corner pieces have been designed an produced
  (by machining) in Rome.
• Molded pieces (H.B. design) in production
• Molded pieces (C.G. design) ready to start the
  production

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Machined Corner pieces

• 45 degree only
• Simple design of the piece (no guard ring)
• 1.7mm thick , 4mm wide slot
• Will be used to build five test gaps (FL02X
  shape)

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Test -Gap w/corner pieces

• These five gaps will be used to test
• gap assembly procedure with the Corner Pieces
• effects of different polymerization times (2-3-4
  days)
• oil flow throughout the new gas inlet
• gap cleaning procedures (before oiling) with
  eptane
• electrical behavior of the Corner Pieces. (HV
  test)
• In production now. Ready for testing and
  inspection next week

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Other Test -Gap w/o corner pieces

• two rectangular gaps with new cylindrical spacers
  (without the guard ring) to test oil flow and
  stanch around the spacers
• Gap1 (1000x2000 mm2) 3 alternate (standard/
  cylindrical/ smoothed cylindrical) spacers rows.
  To be opened for inspection
• Gap2 (500x500mm2) cylindrical spacers to test
  currents
• In production now. Ready for testing and
  inspection next week

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Near future plan

• 220 backelite plates are already at GT but
  production cannot start until the new oiling
  system have been installed and tested
• Current estimation is the end of July
• June-July activities
• Complete the test on the gaps w and w/o the
  corner pieces (done in the next two weeks)
• Make and test few gaps with the H.B. molded
  corner pieces as soon as they are at GT
• Go ahead with the C.G. molded corner pieces to be
  used as backup solution if HB pieces fails

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Near future plan

• Two scenarios possible depending on the results
  of the test we are going to do in June/July
• H.B. molded pieces works fine (known by the
  middle of July) official pre-production can
  start the first week of August.
• H.B. molded pieces fails the test. C.G. pieces
  are ready for the end of July official
  pre-production can start, after testing the new
  pieces, the last week of August (after the 2
  weeks August stop of GT)

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Construction schedule

• The duration of the construction is tied up to
  the time needed to test the chambers with cosmics
  (roughly 10 w.d./10 chambers, including unloading
  and re-loading the test stand, gas conditioning,
  data taking and analysis)
• 100 chambers 100 w.d.
• By starting in August up to 4 bunch of 12
  envelopes each could be sent at SLAC before
  Christmas .
• The last delivery to SLAC could be done (120
  chambers total) around the end of March