Electrical cable tray was installed along the pipe rack, our subcon using ss bolt to fasten the suuport and cable tray, is their a galvanic reaction of two metal. SS & Steel
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"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
The OP stated that the two metals are steel and SS. Now in this situation I think that it is reasonable to assume that SS means Stainless Steel and not Social Security or Schutzstaffel. The OP did not state which alloy of stainless steel or the thickness of the galvanized coating on the steel but I don't think that this matters here.
Getting back to the original question, the only corrosion concern I would have is any locations on the galvanized steel that have been badly scratched or cut to expose the raw steel. At these sites a simple cold galvanize spray coating on the raw steel should do a great job sealing this.
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"Don't disturb my circles." translation of Archimedes last words
You may have a problem in a humid environment. As Redfred said a simple anti corrosion coating should do the trick.Chart from : www.engineersedge.com/galvanic_capatability.htm
As far as this hardware selection, you can do anything you want. You obviously have a disagreement with someone over this choice of hardware being used. (I don't know if you agree with this choice or don't agree. A good obfuscation to get a proper answer.) To settle your disagreement you require a sound, well reasoned engineering perspective on the compatibility of these two materials in your yet to be specified environment.
Now as far as your own ability to coming to a sound, well reasoned engineered choice. A choice where you fully understand the chemistry and mechanics of stainless steel hardware on galvanized steel, lets look at the evidence. You obviously have access to the vast resources of the internet. You are here and have asked us to solve your problem. Our answers have included an unreferenced but reasoned answer (that may or may not be correct) and a selection of a cited reference table that requires you to interpret the answer. After being given this information and with all of the additional services the internet can provide you still ask us to solve your problem.
I'm sorry to say that we cannot help you with your real problem. The real problem is that you cannot support your side of this disagreement with a well reasoned explanation when resources and answers are provided.
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"Don't disturb my circles." translation of Archimedes last words
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