Star-fst-l mailing list

["Visser, Gerard" <gvisser AT indiana.edu>]

Don't you think the "barb" is meant to have an tubing with ID which is a _close_ fit over the region I marked in pink here, and have clamp(s) over the region I marked in blue?

Riding up over the region I marked in red looks like a recipe for leaking,

But, like I said, it is hard to judge from afar and I certainly must defer to you guys. I don't want to generate a big long discussion if it doesn't help anyways.

And yeah this "barb" is kind of unusual in design and I can believe it may be hard to deal with.

I am sure you guys will converge on the proper solution.

     - Gerard

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From: Xu Sun <sunxuhit AT gmail.com>
Sent: Thursday, May 27, 2021 5:15 PM
To: Visser, Gerard <gvisser AT indiana.edu>
Cc: L Star-fst <star-fst-l AT lists.bnl.gov>
Subject: Re: [Star-fst-l] FST cooling tube leak : We might have a solution

 

Hi Gerard,

> By the way, all this cooling business is not my worry but in these pictures including the latest it _appears_ that the tubing is inserted too far over the "hose barb" on module.

This is because that "hose barb" is the only place we could put clamps on except the barb in the front of the stainless steel tube.

There is no other place on the cooling tube that can be clamped on and crates a good sealing. 

Best,

Xu

On Thu, May 27, 2021 at 5:08 PM Visser, Gerard <gvisser AT indiana.edu> wrote:

Maybe. I don't know, not a judgement I can make. It sounds better to use a novec-resistant tubing.

By the way, all this cooling business is not my worry but in these pictures including the latest it _appears_ that the tubing is inserted too far over the "hose barb" on module. I don't understand why it would be done like that and it looks wrong to me, But it is hard to really judge from afar.

     Gerard

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From: Xu Sun <sunxuhit AT gmail.com>
Sent: Thursday, May 27, 2021 5:03 PM
To: Visser, Gerard <gvisser AT indiana.edu>
Cc: L Star-fst <star-fst-l AT lists.bnl.gov>
Subject: Re: [Star-fst-l] FST cooling tube leak : We might have a solution

 

Hi Gerard,

That's a good question, but I don't have any answer right now.

We will need to see how the test goes and also need input from Rahul and Bob.

But it was used in PHENIX for some time, maybe it's fine?

Best,

Xu

On Thu, May 27, 2021 at 4:57 PM Visser, Gerard <gvisser AT indiana.edu> wrote:

hi Xu,

   In such case, don't we have to worry about the resulting contamination "plating out" elsewhere in the system and causing trouble?

    Gerard

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From: Star-fst-l <star-fst-l-bounces AT lists.bnl.gov> on behalf of Xu Sun <sunxuhit AT gmail.com>
Sent: Thursday, May 27, 2021 4:51 PM
To: videbaek <videbaek AT bnl.gov>
Cc: Star-fst L <star-fst-l AT lists.bnl.gov>
Subject: Re: [Star-fst-l] FST cooling tube leak : We might have a solution

 

Hi Flemming,

Bob and Rahul told us the novec will eat up the materials and the leaking rate will increase with time.

Best,

Xu

On Thu, May 27, 2021 at 4:48 PM videbaek <videbaek AT bnl.gov> wrote:

Hi

Did Rob indicate the rationale for exchange every year. Possible Rad
damage ?
It would be good to know.

best F.


On 2021-05-27 16:37, Zhenyu Ye wrote:
> This is good news, indeed.
>
> If it works, it would solve our problem for the upcoming Run.
> But it also brings a new potential issue, that we need to replace the
> cooling tubes every year.
> If we can avoid it, it will be the best.
>
> Zhenyu
>
>> On May 27, 2021, at 2:33 PM, Tribedy, Prithwish <ptribedy AT bnl.gov>
>> wrote:
>>
>> Hello everyone,
>> We have good news to share with you. With a new kind of tube that was
>> previously used by Phenix, we might have a solution to our leak
>> problem. We need to do more tests, but I think this is a good
>> progress.
>>
>> Remember we had the following issues:
>>      • The hard tubes were very stiff, bending radius was large but had
>> less leak.
>>      • The soft tubes had major leaks between layers.
>> A solution came after Bob/Rahul contacted Robert Pisani from Phenix.
>> From them we got this third type: Tygon 2001 plasticizer free" tubes.
>>
>> With our pressurized air setup, we see NO LEAKS. No more bubbles with
>> soap.
>>
>> Also, it's much cheaper. It costs like $2.5 c per ft (compared to
>> $20-80 for the previous soft tube we were using).
>> According to PHENIX experts, they should be replaced once every year
>> -- I think that is feasible.
>>
>> So, we'll get 25 ft of these tubes tomorrow and this way we have the
>> full weekend to do the testing.
>> If things look good in next couple of days and no leaks are found‚ WE
>> MIGHT HAVE A SOLUTION.
>>
>> We will keep you updated.
>> Best,
>> Yu, Xu and Prithwish