[Moller_intdet] [EXTERNAL] Re: Detector mounting structure

[Michael Gericke]

Hello,

I have uploaded the CAD files for this conceptual design to my google drive:

https://urldefense.proofpoint.com/v2/url?u=https-3A__drive.google.com_drive_folders_1lxn4AS-2DEwjjvAEL1oNrxW5snb5x-2DbxcF-3Fusp-3Dsharing&d=DwIDaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=sAcmfDnmgp80OHNp8BT9B0ppMns-xHhof47DzJMhOgs&m=mkqit__5P_yVofmX4jJw5E6xhkgIv6SPFEriyPgZ1N0&s=e2l9slZkfbAIKIidZFilIzpIcbAYIFcX4SJrDH1QJl4&e= 

Most of the files are in Inventor format, but I also generated some step 
files. Let me know
if you need any other formats.

Cheers,

Michael

--
Michael Gericke (Ph.D., Professor)

Physics and Astronomy
University of Manitoba
30A Sifton Road, 213 Allen Bldg.
Winnipeg, MB R3T 2N2, Canada

On 2019-11-07 10:44 p.m., Michael Gericke wrote:
> Hello everyone,
>
> I am attaching my conceptual design for the detector mounting structure.
> Since we haven't had anything of this sort ready for getting meaningful
> cost estimates (and I had to do this for the CFI quotes anyway), I 
> decided
> to make a design that could be submitted to a company for a quote 
> request.
> I am still waiting for them to get back to me.
>
> The attached pdf is CAD generated and you can zoom in and rotate the
> models. If you wish to have the CAD files, I'll be happy to upload them
> somewhere. The attached movie illustrates how the individual modules
> can be assembled (sorry, the files are fairly large, so one has to be 
> patient).
>
> A few points I want to make:
>
> 1) As I said, this is a conceptual design and I am pretty sure it can 
> be optimized.
>     I tried to balance mounting rigidity with as small a material 
> budget as possible,
>     but I am sure one can further improve on that. Maybe it will 
> provide some food
>     for thought for the group working on the structure design.
>
> 2) Some of the parts are complicated; The company I spoke to said that 
> they could
>     either 3D print or use a 5 axis CNC to make the more complicated 
> parts, but I expect
>     the cost to be higher than what we budgeted up to now, especially 
> if we decided that
>     we want to us a carbon fiber based material, rather than aluminum.
>
> 3) I think I know how one could simplify the complicated parts and 
> make it cheaper, but at
>     the cost of less rigidity, I think.
>
> 4) This design treats the PMT-LG-Quartz assembly as a unit, which will 
> make light tight sealing
>     easier. The mounting plates for each module would allow using 
> washers to adjust angles, if
>     need be.
>
> 5) The extra space needed by the "skeleton" for each module causes the 
> rings to be spread out
>     a little more, in the beam direction. One can play around with the 
> structure to squeeze that
>     together, but I would caution against overdoing that, as it could 
> get impossible to assemble
>     and service parts. It would be better to adjust quartz tile size 
> and mounting radii.
>
> 6) I think we will need two separate, concentric cylindrical 
> structures, one that will hold the
>     modules, as in this design, and a separate one that will hold the 
> shielding. I don't think we
>     can afford to have a high weight load on the module structure, as 
> it was suggested in the
>     previous designs.
>
> 7) We will need to think about whether we need to flush the light 
> guide with dry air, to prevent
>     possible reflectivity degradation, which would further complicate 
> the design. The modules would
>     support a light and air-tight bag around each one and one could 
> imagine feeding the air through
>     the PMT housing.
>
> So, while this still just a preliminary design, I think it can serve 
> as a first basis for a real cost
> estimate of the mounting structure and will show the CDR committee 
> that we have at least
> thought about the mounting details.
>
> As soon as I have a quote for the module parts, I will pass it on to 
> Carl.
>
> Cheers,
>
> Michael
>
>
>
>