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Dalmo
08-10-2007, 01:17 AM
Hy!
Guys!


I opened a 50ton Screw Compressor Hitachi, and the color of all internal pieces ( least the bearings) were with cupper colored!:eek:

Someone knows what happened?!?
The Compressor was never in maintanence in 5 years !

Someone knows if I will be able to remove this "layer" in all pieces ?

The gas is R22 with POE (sintetic ) Castrol Icematic SW220.

All informations are welcome!!:rolleyes:

Dalmo

absrbrtek
08-10-2007, 04:57 AM
Copper plating. You will sometimes see it with systems that have a high moisture content. Have you had an oil analysis done?

Dalmo
08-10-2007, 10:23 AM
Absrbrtek,


I did a analysis with Oil kit Sporlan for POE oil, :rolleyes:and the color was red, indicated that it's OK, until opened the Comp.

DO you think it's better change all pieces or Can I remove Copper Plating ?:(

Regards

Dalmo

Argus
08-10-2007, 10:24 AM
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It indicates the presence of water in the system and the long-term generation of acid, probably hydrochloric acid, as it is R22.

The damage is done.

The likelihood is that there is also bearing damage throughout due to the copper plating.

.

Dalmo
08-10-2007, 12:23 PM
Thank you !Argus

"The damage is done. ":(

I will replace all with spare parts , and the bearings too!:o

Do You Know what Cleaner I need to use inside of the Crankcase?

Regards!

absrbrtek
09-10-2007, 02:45 AM
An oil analysis is not just an acid test. It determines wear metals, viscocity, additives, acid content, moisture content and identifies possible sources of the problems to name a few items in the report. Ferrographic analysis tends to be more detailed than Spectrographic analysis.

As Argus stated, the damage is done. Copper Plating is an electrolitical reaction, and for lack of a better term, bonds the plating to the surfaces. It will not come off. JMHO



Absrbrtek,


I did a analysis with Oil kit Sporlan for POE oil, :rolleyes:and the color was red, indicated that it's OK, until opened the Comp.

DO you think it's better change all pieces or Can I remove Copper Plating ?:(

Regards

Dalmo

Dalmo
09-10-2007, 11:34 AM
Absrbrtek,

Thank you for replay.

I enjoy this Forum, I am always learning!!:rolleyes:


Regards!:)

Argus
09-10-2007, 12:00 PM
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If you have a lot of copper plating on the compressor a new compressor or a re-build is the only solution.

Next, you still have the problem of what caused it.

Water is the obvious answer and how it got in there in the first place, but depending on how long it has been working like this will also have an influence on what is also in the system. You will certainly have contaminated refrigerant, a selection of acids (an unknown quantity) and possibly decomposed oil.
To cause copper plating you obviously have a quantity of moisture greater than the drier’s ability to absorb it, so we are not talking about a couple of hundred PPM..(parts per million).

That’s a potentially lethal soup for the next compressor if you don’t clean it properly.

Commercial acid tests are fine for small domestic units (I assume that this is not a small system, because you said that it was a screw).
They will tell you if you have acid present, but not how much.
For serious contamination, you need to know what is in the soup, before you can begin to decide how to clean it up.

I suggest your next course of action should be to get a full, professional analysis of the refrigerant and the oil. Do both at the same time and ensure that the samples are taken in new, clean containers otherwise you will be paying for false results.

If you use a non-refrigeration based laboratory, it is essential to draw up a specification list of what they should be looking for. Give this some thought.

I don’t know what services are available in Brazil, but refrigerant manufacturers would have the facilities to do this and you may want to call their head offices.

It is not free or even cheap, but it will be a lot less money than a second dead compressor in a few months.

Hope that this helps.

.