Good morning,

We are having issues with some of our tubulars cracking in shot peened areas. We shot peen non-magnetic tubulars on the threaded sections (API Connections) with the objective to relieve machining stresses and mitigate galling. The material of the tubulars is 15-15 HS from Carpenter.

Could I have your opinion about the importance of shot peening these non-magnetic tubulars with non-magnetic media, benefits of doing so and risks of not using Stainless steel shot.

I am trying to understand the pro and cons of shot peening with carbon steel media vs stainless steel media. Would both media improve the corrosion and oxidation resistance of our tubular the same amount?
What would the risks of shot peening nonmagnetic tubulars with carbon steel media?

If we were to shot peen our nonmagnetic tubulars with regular carbon steel shot, would we have a greater risk for stress corrosion cracking? Would it make them more prone to develop oxidation and corrosion?

Thank you.