Effect brazing steel-copper with R-600 application

[Aria]

Dear All,

In case of R-600 development, i want to asking about safety regulation.
as we know that refrigerator pipping consist of steel and copper tube.
If we want to apply R600,is still have a permission to brazing steel-copper ?
Because in IEC standard mention that different electron valency between 2 metal is forbidden to apply in R-600 (corrosion rate catalyst --> Leakage) .
In my opinion, no problem if we still use brazing steel-copper to R-600 application, because brazing spec Steel - copper is already defined, use flux and silver solder.

Need your advise,

Thank you,

Regards,

[Aria]

no one answer my question...

[Grizzly]

Hi Aria.
I cannot speak for anyone else but I struggle with the way you have worded your question.
The few R600 units I have worked on were domestic with Compression fittings.
I have even Copper to Copper brazed joints which were leaking.
I know of no reason why you cannot Soft Braze Dissimilar metals (Steel - copper etc.) with Silver Solder.
The issue for me would be making sure the pipes are purged and Nitrogen is bled through them before applying heat.
Grizzly

[RANGER1]

http://www.refrigeration-engineer.co...php/t-730.html

These people appear to know what they are on about on this subject!

[chemi-cool]

There is no such problem inside the the silver soldered steel to copper joint if you preform deep good vacuum.

The chemical reaction can only occur in oxygen environment, and to protect the soldered joint on the outside, man invented paint.

[Peter_1]

Not exactly true Chemi... yo can not use phosphor solder with natural gas here because there's a chemical reaction between the phosfor and the gas. The gas makes the solder like a sponge

[Aria]

Thanks all for the advice. just want to make sure my opinion, because my friend still in their opinion, that R600 applications should not be use steel & copper brazing.

[nike123]

Not exactly true Chemi... yo can not use phosphor solder with natural gas here because there's a chemical reaction between the phosfor and the gas. The gas makes the solder like a sponge

He did not mentioned phospor solder!

There is no such problem inside the the silver soldered steel to copper joint

[Aria]

for brazing is no problem for all refrigerant. my question is related with safety factor R-600a . all we know that R-600a is flammable. may be my friend worried about that, so he not agree to use brazing for R-600a.

Nice to discuss in here.

Thank you