coppergrease and stainless, subsea

[numpty2]

Is copper grease to be avoided when assembling SS (316) bolts into SS (316) for subsea use?
What about SS bolts in Monel and Inconel bolts in Monel?
Can you use copperslip with these materials or avoid?
Kev.

 

[cloa]

It would depend a lot on your actual subsea location and depth and local conditions but if you consider only the galvanic potential and the enormous area effect then if there is even a little water to form an electrolyte then the copper in the grease in contact with any of those materials. The simple fact that these copper greases are not rated for subsea probably means they will probably make the crevice worse and give you crease corrosion under your bolt.

 

[numpty2]

And does that apply to inconel bolts in monel as well?
We have received some monel pipes with inconel SHCS in the flanges that have been lubed with copperslip.
I have always been told not to use copperslip on anything that goes subsea, but maybe these materials are so resistant to corrosion that it doesn't matter?
Kev