Field Cage Mockup Status Mike Wilking Stony Brook University DUNE - - PowerPoint PPT Presentation

Field Cage Mockup Status

Mike Wilking Stony Brook University DUNE Engineering Meeting April 27, 2016

1

Field Cage Design

• Work on the mockup began

last month

• We are currently assembling

the original field cage design

• Cross bracing I-beams were

not included

• For this first mockup, we are

not planning extensive tests

• f manipulation, mechanical

stability, cold testing, etc.

• For now, we are developing

assembly procedures, QC of prefabricated parts, production of in-house machined component, etc.

Original Design New Design

2

Profiles

• Currently using prefabricated stainless steel profiles
• The pieces we received were pinched closed at the ends
• Cut to length using a (somewhat dull) bandsaw (~1 hour for 50 profiles)
• Ends we deburred with a grinding wheel, filing, and sanding (~6 hours for 50 profiles)
• Goal was to remove loose pieces; endcaps can handle minor imperfections
• Decision on stainless steel vs extruded aluminum in May?
• If aluminum, will post-processing be necessary, or will these come cut to length?
• There are concerns about scratching the profiles surfaces during assembly
• Stainless steel was quite resilient; aluminum may be more delicate
• In the new design, the profiles extend further from the I-beams
• Some concern about mechanical deformation depending on the final material

3

I-beams

• Profiles holes were cut via waterjet
• In a few places, the I-beam coating began to peel, exposing the rough fiberglass

surface below

• All of the cut holes and I-beam ends had a similar rough surface
• Filing/sanding may be an option (with a solvent to minimize dust)
• Screw holes did not always line up properly due to

slight twists in the I-beams and rounding in the I-beam fabrication

• Some amount of filing will likely be necessary
• Can tiny fiberglass shards, emitted in the LAr, cause any

problems? Bad for the pumps?

• Could consider coating the exposed surfaces. Epoxy?
• The rough surface of the profile holes can potentially scratch profiles
• We may want to consider a coating for these holes
• This problem may be a larger issue for aluminum profiles

4

Component Machining

• Profiles are secured to the I-beam using slipnuts
• Several versions have been machined at Stony Brook with different

screw sizes, thicknesses, etc.

• Can we continue with 304 Stn. Stl. even with aluminum profiles?
• We currently have a small number of endcaps
• We are looking into machining some more
• The mechanism to attach endcaps to profiles

has not yet been finalized

5

Assembly Status

• Initial assembly of I-beams and profiles is complete
• We should soon receive additional nuts, M4 ↔ M6

screws, etc. in a few different material types (stn stl, nylon, G10?)

• Different material options are under consideration
• Ground planes from CERN should arrive this week

6

Next Steps

• The amount we can learn from further work with the old

design is limited

• We hope to move to the new, 2 I-beam, design in the

next few weeks

• A design for the temporary manipulation frame for the

2 I-beam design is ready

• We plan to begin fabricating this soon
• This will allow us to begin manipulating an assembled

module using the overhead crane (lifting, tilting, etc.)

• Preparations are underway for the clean tent (gray room)

and cold test setup

• This isn’t necessary for the first few mockups that will

be sent to Ash River

7