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Grizzly
05-12-2014, 07:14 PM
Just for fun Guys, photos of leaks found on 3 different sites all within the same week.

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Pics 1 &2 are ammonia plants and the smell led me to the leaks, 3&4 were on a 404a system where one of my colleagues had Identified 4 as a possible leak several weeks earlier.
By the time I was onsite 4 and 3 were not to difficult to find / confirm.
Cheers Grizzly

al
05-12-2014, 08:17 PM
A busy week Grizz!

monkey spanners
05-12-2014, 09:11 PM
Makes a change from leaky danfoss solenoids!

Grizzly
05-12-2014, 10:33 PM
No1 Actually has ammonia Vapour leaking from it, which can be seen as a white smoke in the photo. It's a low pressure liquid line which feeds a comp oil cooling circuit.
The Comp and the relevant pipework was isolated, prior to purging and to allow the pipework to be cut out and
replaced.
The 2nd cannot have been in place more than a day, it is a balance line between 2 liquid line pumps. So the pump discharge pressure of whichever pump is running can be read.
The Ermeto tee which is leaking has turned the ice blue, which leads me to think it has some copper in it?
(As I am guessing they are Copper sulphate crystals?)
A heavier grade Hydraulic tee has been ordered. The pump pressure reading is being ignored in the meantime.
The theme next week will be adding Gas I suspect!
Grizzly

Magoo
05-12-2014, 10:58 PM
Hi Grizzly.
Pic one looks like copper pipe. Or am I missing something. Copper and ammonia do not go well together.
With that tee fitting use swagelock. Expensive but never leak.

Glenn Moore
05-12-2014, 11:13 PM
Hi MS
Which Danfoss valves leak ? Is this a new problem or an old problem?

Grizzly
06-12-2014, 09:47 AM
Hi Grizzly.
Pic one looks like copper pipe. Or am I missing something. Copper and ammonia do not go well together.
With that tee fitting use swagelock. Expensive but never leak.

Hi Magoo.
Your right about copper and ammonia not mixing, hence my comment about the copper sulphate (blue staining on the fitting in Pic 2).
Picture one is not copper but a very rusty steel pipe (Circa 1970's) which was originally painted with red oxide paint. You cannot see it in the picture but the rust scabs are linear and follow the curvature of the bend.
Much like if you look at the edge of a piece of slate.
The consensus is it has rusted in layers because when originally bent heat had been applied? Causing stress lines, or would it apply if cold drawn?
Not sure myself!
Thanks for the tip abut Swagelok, I suspect this fitting is a rogue fitting because the 10l Hydraulic fittings I normally use are supposed to be good to 3000psi and all steel. This one isn't all Steel!
Just thought pictures from the coal face would be of interest to some?
Cheers Grizzly

hookster
06-12-2014, 02:35 PM
Nice pictures Grizzly, pictures 1,2,4 are all age related showing very poor maintenance regimes and a 1,2,3,4 low level of installation deviating from BS standards.

My pet hate is arriving to find the installers have cut corners i.e in picture 1 not supporting pipes at every change of direction. Picture 2 & 3 unsupported loads. Picture 4 unsecured fittings.

Most refrigerant leaks can be designed out!

xxargs
06-12-2014, 03:20 PM
An ammonia complex with copper is itself very blue and very alkali - not need sulphur to make blue colour.

Visual part of threading on T-junction seems very much colour of brass, and brass have big part of copper...

...and my own experience is almost impossible to make high vacuum proof leak-free connection with PFTE-tape winding on pipe threads and works better in this case if using thread sealing from Loctite etc. - but here also must handle dry ammonia.

Grizzly
06-12-2014, 04:08 PM
Ok xxargs you got me copper sulphate crystals they may not be, but it explained what I meant!
Whatever happened to "Just for Fun"?
When I find a pump discharge running in negative pressure, I might consider using something other than PTFE Tape.
I, nor the Projects engineer who was working with me would dream of using brass knowingly as I believe I have implied above.
Did you bother to read any of the above posts?
Grizzly

xxargs
06-12-2014, 08:08 PM
I reading all but English is not my native language so i can misunderstood things and underlay meaning in discussion and write thing in wrong way. Is my not intention to make critic and so.


Copper complex with ammonia (Cu(NH3)4+2) is dark blue and can be very, very strong alkali and solve for example cellulose to liquid form (is very few other very strong chemicals can do same thing, conc. NaOH and KOH can not solve cellulose for example.) and this way cloth manufacture make fiber called 'rayon' - so if enough concentrate, is not funny thing splashed on naked fingers or face/eyes ie. can be very skin etching - so blue coloured ice should melted and diluted with water before going waste or handled with unprotected hands.

I think not problem for ammonia guys with protection gear and suit - but later if not diluted/proper handling...

---

my observation leaking about PFTE-tape on pipe thread coming from trying make equipment handling vacuum lower than 0.001 mBar and find out is almost impossible make it leak-free depend PFTE-tape is laminate from beginning (ie tape) and crush and rips apart from sharp thread edge with tighten pipes and pores exist trough whole junction and make very small and constant leak even if tighten very hard.

This is not issue if handling water, steam, pressured air and so on - but for F-refrigerant, corrosive gas etc. is different task.

monkey spanners
06-12-2014, 08:15 PM
Hi MS
Which Danfoss valves leak ? Is this a new problem or an old problem?

This one, it was under a year old i think when i found the leak,

https://www.youtube.com/watch?v=yzvmJFSRYOc&list=UUxJXtG4fhbM7gE3FRcissrQ

Grizzly
06-12-2014, 09:13 PM
I reading all but English is not my native language so i can misunderstood things and underlay meaning in discussion and write thing in wrong way. Is my not intention to make critic and so.


No further explanation needed.
Grizzly

hookster
07-12-2014, 07:52 AM
https://www.youtube.com/watch?v=yzvmJFSRYOc&list=UUxJXtG4fhbM7gE3FRcissrQ

Same as the others badly installed making stem sealing fail. There is a mounting hole on base of the solenoid in the vid and I guess fridge circuit manufacturer thinks it is a show piece! :p

So we have a great chunk of electromagnet supported by the flares and copper tube! Each time solenoid operates the valve lifting forces are transmitted about the fitting. This was a leak waiting to happen and the potential for critical failure.

If as an industry we wasted as much time and money on improving the standard of installations and refrigerant containment we could still be using refrigerants without glides, High pressures and all the other nastiness that the chemical industries are producing. :confused: