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

[Jack Segal]

   I turned off all the flow meters. Turned them on a section at a time. I think you
are just using a lot of gas. I'm not sure how accurate those visual meters are at
low flow. Also, they are calibrated for air. You are using Ar/CO2.
   What is the make and model of the visual flow meters?

On 9/28/2021 12:46 PM, Jack Segal wrote:
> 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
>>>
>>>
>>
>>

-- 
John(Jack) Segal
Halls A and C Spectrometer Support Manager
Thomas Jefferson National Accelerator Facility
12000 Jefferson Avenue
Suite 12
Newport News, VA 23606-4486
Phone: (757) 269-7242
Cell: (757) 320-9977