[Dsg-halla_gem] [EXTERNAL] SBS gas distribution rack moved to EEL/125; help setting up?

[Jack Segal]

Isolate the GEMs and restart flow one at a time.

Sent from my iPhone

> On Sep 28, 2021, at 11:39 AM, jboyd at jlab.org wrote:
> 
> To all,
> 
> Anu and I set up the gas distribution from the gas cylinders, to through
> the gas rack, and onto the GEM layers. We have been flushing and flowing
> gas. It seems that the gas loss rate is a bit more than what we would
> expect given the flow rates that we have set. We are losing about a bottle
> a day for our 8 layers of GEMs. We expect that 1 bottle should be about 3+
> days.
> 
> Therefore, we are suspecting a leak somewhere, perhaps on the gas
> distribution rack. I checked around the gas cylinders and the connection
> manifold and couldn't find any leaks (I did find one but I was able to
> fix/seal it).
> 
> What should we do about getting the setup of the gas rack and possibly the
> cylinder/manifold setup leak tested and checked?
> 
> Thank you for the help.
> 
> Best,
> 
> John
> 
>> Hi Brad,
>> 
>> We discussed the SBS gas distribution in our meeting today. I will
>> schedule a time to come over and install a Raspberry Pi in area for
>> monitoring.
>> 
>> It looks like the rack accessory box has been relocated from the Hall to
>> EEL 125, George is scheduling to connect the gas flow sensor chassis
>> channels to the appropriate flow meters.
>> 
>> After these steps are completed, I'll send an email so Kondo's group can
>> connect their detector gas lines to the output side of the gas flow sensor
>> chassis and hook up the premix bottle to the regulator input.
>> 
>> 
>> 
>> Regards,
>> Marc McMullen
>> Sr. Instrumentation Designer
>> Detector Support Group
>> (757) 269-7738
>> 
>> From: Brad Sawatzky<mailto:brads at jlab.org>
>> Sent: Tuesday, September 21, 2021 10:51 PM
>> To: Kondo Gnanvo<mailto:kagnanvo at jlab.org>; John
>> Boyd<mailto:jboyd at jlab.org>; Rathnayake, Anuruddha
>> (adr4zs)<mailto:adr4zs at virginia.edu>; Marc
>> Mcmullen<mailto:mcmullen at jlab.org>
>> Cc: dsg-halla_gem at jlab.org<mailto:dsg-halla_gem at jlab.org>; Jack
>> Segal<mailto:segal at jlab.org>
>> Subject: [EXTERNAL] SBS gas distribution rack moved to EEL/125; help
>> setting up?
>> 
>> Hi Marc, et al,
>> 
>> The SBS GEM gas distribution rack was recently moved to EEL/125.
>> That is where the SBS GEM layers are being stored and worked on.
>> 
>> Marc, can your group support the GEM group in completing the setup
>> of that gas system so they can start flowing gas to the layers in
>> EEL/125?  It will need to be reconnected to the network, some gas line
>> 'jumpers' need to be run between the two sides of the rack, and lines
>> need to be run from the rack to the GEM modules themselves.  (I believe
>> Jack fixed the issue with i2c multiplexing in that rack.)
>> 
>> I also moved a large spool of 1/4" poly into EEL/125 so fresh gas lines
>> can be run.  General consensus is to position the rack in the most
>> convenient location in EEL/125 and run (relatively short) gas lines of
>> the needed length to the individual GEM modules.  We will cut a set of
>> new (longer) gas lines for the final setup in the Hall in a couple
>> months.
>> 
>> I'll be out of town for about a week, but I've discussed this with John
>> Boyd and Anuruddha, and they are generally in either EEL/125 or /126.
>> 
>> -- Brad
>> 
>> --
>> Brad Sawatzky (he/him), PhD <brads at jlab.org> -<>- Jefferson Lab/ Hall
>> C/C111
>> Ph: 757-269-5947  -<>-  Fax: 757-269-5235  -<>- Pager: brads-page at jlab.org
>> The most exciting phrase to hear in science, the one that heralds new
>>  discoveries, is not "Eureka!" but "That's funny..."   -- Isaac Asimov
>> 
>> 
> 
>