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Agenda/Minutes of the VIS Meeting on 2016/9/30

2016/9/30 13:30 -

Participants: Takahashi, Hirata, Okutomi, Sato, Tanaka, Akutsu, Mark, Fabian, Aso, Raffaele

Progress report

Schedule Chart (PDF,MPP)

Type-A (Takahashi)

• Minutes of Type-A Meeting

• Pre-isolator: Pre-isolators will be assembled in ATC. IP+TF will be transported from Akeno on 3rd October.
• EQ stop, release sensor, dummy payload: Production is on going. Met with the company person on 16th.
• Bottom Filter: Assembly of the second BF is on going.
• BF damper: Made the specification document with the drawings. Asking a quotation to a company. Actuator efficiency of LVDT prototype was measured.
• Maraging wire: New design around head was shown by ATC. Tensile test is in preparation.
• BF bearing rust issue: found SUS parts. Will buy them and replace the existing ones if we find rust during the installation work.

• BF LVDT test results

Type B (Mark)

• Type B Past Week Summary, weeks of 9/19 and 9/26
  • Fabian, Mark and Kuwahara-kun did BS installation at Kamioka:
    • The BS clean booth was modified 9/20-21 to allow crane access. The area was fairly clean when Fabian inspected it on 9/26, but there were lots of metal flakes stuck to tape holding foil over the slit in the top of the clean bag.
    • Mark created a new Type B rtcds model and MEDM screens for the BS, adapting the TypeBb/PR3.
    • Mark and Kokeyama-san debugged the new model, fixing several issues.
    • Kuwahara-kun derived OSEM2EUL and EUL2OSEM matrices.
    • Mark set up OSEMINF filters using measured OSEM calibration data to return outputs in µm.
    • Mark took free-swing data on the TM stage to get the pendulum mode frequencies for comparison to the SUMCON model.
    • Mark and Fabian debugged the coil output to the OSEMs. (At first the coil drive was not giving output because it did not have BIO inputs and so was reading the test input, not the main input. And for a while output failed because of a loose cable to the sat amp.)
    • Mark took fixed-sine TFs to check the polarity of the coil-magnet combinations.
    • Mark installed a BIO card in the PR2 rack and added cables from the TM voltage and current monitors to as-yet unused IM OSEM inputs to check the calibration.
    • Fabian wrapped the assembly frame in cling wrap to see if it helped with wind during TFs.
    • Kuwahara-kun derived the coil driver switchable filter TFs and matching software compensation filters.
  • Hirata-san:
    • Finished 3D CAD of SRM in tanks (but some work was lost due to a hard disk crash).
    • Did 3D and 2D for new maraging rods, stub flags for PR/SR (ditto re hard disk).
    • Measured/tested Type A BF #8 and started assembling #9.
• Longer term to-do list
  • Do Inventor assembly for SRx in chamber and on assembly frame (Hirata) - SR2/SR3 DONE, SRM ongoing.
    • Part "disk security" top has to be modified - screw positions do not match.
  • Write more of payload assembly procedure (Fabian) - ONGOING

  • Write more of BS Assembly Procedure E1504235, E1504235 draft (Mark) - ONGOING

  • Lower breadboard installation to be incorporated into the procedure document.
  • Work on BS simulation (Fabian)
  • Do BS Simulink model (Mark, Kokeyama) - TM/IM/BF level DONE
  • Do 2D drawings of SR2 parts (Hirata)
  • Redesign SRx IM wire clamps for larger prisms, remachined RMs
  • Order SRM/PRM parts (Hirata/Shoda)
  • Order SRx fasteners (Hirata)

Type-Bp (Shoda)

• Modification Parts
  • Akutsu-san and others helped us complete the spec document.
  • We got final quatation. After some updates on spec document and the assembly drawings, we will proceed to an order soon.
• Mirapro
  • Hirata-san updated the wire design and hook design. Some other parts only used for Type-Bp should be also updated.
  • How to order is under discussion.
• Mirror preparasion
  • Discussion about the jigs for removing the current flags from the PR3 and spare mirrors are ongoing with Hirose-san.
• F7 LVDT
  • The sensor coupling noise according to F7 LVDT is updated. Since the noise level is close enough to the requirement, which is set with the 10 times mergin, the sensitivity should be OK.

IMMT (Ohishi)

• Put a report here

Watchdog system (Tanaka)

• Working on the design of the next version.

Safety

• I forgot to discuss this

Discussion

• Inspection report of the GAS blade from Virgo (Takahashi)
  • Non discontinuity of the nickel coating layer has been observed.
  • The blade did not present any scratch nor incipient rust formation.
  • 1.6ppm of hydrogen concentration was observed.
  • Measured tensile strength was 1.9GPa. In the case of doping 12.6ppm hydrogen, it was 0.6GPa.
  • Conclusion: we can continue to use our blades.
  • A/I: Ask Virgo for SEM photos. Also ask how they measured the hydrogen concentration as well as the method of doping hydrogen. (Takahashi)
• Maraging and SUS rod issue follow up.
  • Information from Virgo (Takahashi)
    • Safety margin in Virgo is as follows. They adopt 1.75 GPa as yield strength.
    • They don't take the stress concentration into account. Interpolating from Type-A case, the smallest margin would become 2.2 .

    F1	2.5
    F2	2.9
    F3	3.1
    F4	3.3
    F7	2.7

    • Two difference between Virgo and KAGRA: Yield strength (1.75GPa vs 1.5GPa) and the stress concentration, which can easily increase the stress by a factor of 1.5 depending on the shape of the neck.
    • Considering the above factors, the Virgo safety factors are probably less than 2 in KAGRA standard.
    • The fact that Virgo had no maraging rod failure in more than 10 years of installation work and operation gives us a kind of justification to go with a safety margin of 2.
  • Which rods to be re-made ? (Takahashi)

    • Material

  • Type-A rod neck diameter
    • Will increase the diameter a bit to make the safety factor above 2.
  • Confirmation of the Type-A installation procedure.
    • According to Takahashi-san , the current installation procedure will not put tension on the rod during the crane operation. Therefore, the chance of giving a shock to the rod will be very small.
    • We need to confirm the above claim.
    • Type-A team (+ interested people) will discuss and confirm the installation procedure at the next Type-A meeting.
    • If the above point is confirmed, we will go ahead with the safety margin of 2.
• IM OSEM noise issue (Shoda)
  • Will discuss at the next meeting.

Site work plan for the next week

• Mon: BS test hanging
• Tue: BS test hanging
• Wed: BS test hanging
• Thu: BS test hanging
• Fri: BS test hanging

Travel Plans

• Travel (Week of 10/3):
  • Takahashi: 3(Akeno)
  • Shoda:
  • Mark: 3-7
  • Fabian: 3-6
  • Okutomi:
  • Fujii:
  • Ishizaki:
  • Hirata:
  • Sato:
  • Ohishi:
• Travel (Week of 10/10):
  • Takahashi: 11 -14 (Extended Chief Meeting/Accelerator check)
  • Shoda:
  • Mark: 10-14
  • Fabian: 11-14
  • Okutomi: 12 -14 (Extended Chief Meeting/Accelerator check/FE code development)
  • Fujii:
  • Ishizaki:
  • Hirata:
  • Sato: 12 -14 (Extended Chief Meeting/Accelerator check)
  • Ohishi:

Next meeting

2016/10/7(Fri) 13:30 - VIS F2F: Oct. 28, Nov. 18, Dec. 2