Re: tagger magnet spec (fwd)

["Guangliang Yang" <y.guangliang@physics.gla.ac.uk>]

Dear Elke,

         Thanks for Jay's comments.

         About the O-ring,   the compression ratio is very important, but I 
also want to know if anyone has any comment on the O-ring diameter. 
Currently, it is proposed to have a 10mm diameter.

         We plan to use non magnetic materials to make the vacuum box. 
Because not all types of the stainless steel are non magnetic material, so 
it's better to specify clearly that we want to use non magnetic stainless 
steel, i.e., austenitic stainless steel.

         The inlet water temperature depends on what we can get, maybe civil 
people can answer this question.

         10 ppm power supply stability is fine for our application.  The 
quotation we got from Danfysik specified that the power supply has +-10ppm 
long term stability.


Regards

Guangliang




----- Original Message ----- 
From: "Elke-Caroline Aschenauer" <elke@jlab.org>
To: <halld-tagger@jlab.org>
Sent: Thursday, November 29, 2007 10:36 PM
Subject: Re: tagger magnet spec (fwd)


>
> Dear all,
>
> some remarks from Jay to the specs for the tagger I send him.
>
> cheers elke
>
>
>
>
> ( `,_' )+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=
>  )    `\                                                  -
> /    '. |                                                  +
> |       `,              Elke-Caroline Aschenauer            =
>  \,_  `-/                                                    -
>  ,&&&&&V         Jefferson Lab                                +
> ,&&&&&&&&:       HALL-D 12C / F381       121-A Atlantic Avenue =
> ,&&&&&&&&&&;      Mailstop: 12H5          Hampton, VA 23664      -
> |  |&&&&&&&;\     12000 Jefferson Ave                             +
> |  |       :_) _  Newport News, VA 23606  Tel.:  001-757-224-1216  =
> |  |       ;--' | Mail:  elke@jlab.org    Mobil: 001-757-256-5224   -
> '--'   `-.--.   |                                                    +
>   \_    |  |---' Tel.:  001-757-269-5352                             =
>     `-._\__/     Fax.:  001-757-269-6248                              -
>            +=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+
>
> ---------- Forwarded message ----------
> Date: Wed, 28 Nov 2007 18:35:25 -0500
> From: Jay Benesch <benesch@jlab.org>
> To: Elke-Caroline Aschenauer <elke@jlab.org>
> Cc: Arne Freyberger <freyberg@jlab.org>
> Subject: Re: tagger magnet spec
>
> Elke,
>
> The first thing that jumped out at me on first reading was at the top
> of page 5: O-ring compression of 20-30%.  I had way too much trouble
> with 20% compression on a system as a grad student.  I'd require
> 25-30% compression.
>
> In the paragraph on vacuum box materials you might write "austenitic
> stainless steel".  Aluminum to stainless welding is non-trivial.
> e-beam welding may be the only choice.  This would be a big e-beam
> welder.  I would specify the temperature range of operation so the
> bidder can do the calculations on differential expansion.  Better yet,
> to allow the bidder as much parameter space as possible specify the
> temperature of the cooling water at the inlet.  The bidder will then
> have to compute the temperature rise of the steel to determine whether
> an aluminum chamber is feasible.  With 20 mm from pole edge to coils,
> it should be possible to add enough thermal impedance to allow an
> aluminum vessel.
>
> If you can live with 10 ppm power supply stability you'll save some
> money.  I think that is Danphysik's standard.  Check.
>
> On page 6, you don't give the unit for the nominal beam height.  It
> has to be meters but you need to write it.
>
> I couldn't click on the link to Yang's drawing using gpdf.  I'll check
> tomorrow on a PC with Acrobat.
>
> Jay
>
>
>
>
>
>
>