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Difference between Stainless and Killed Carbon Steel

Hello my name is Kris Young,

I'm rather new to the construction industry, working in a QA/QC position. While I do have a quality background, I'm new to the use of different metals that are used in oil refineries.

My question is: What are the differences between stainless steel and killed carbon steel?

I am asked to sort pipes by line classes and I haven't been able to find an answer online that I can wrap my mind around. A simple explanation would be wonderful.

Thank you for your time.

Kris Young
QA/QC - Brewer, Maine, USA
June 19, 2009

Hi, Kris. The chemical composition of carbon steel is basically iron, with a very limited amount of carbon in it. If the carbon content exceeds a certain low amount, about 0.24 percent, it becomes necessary to add silicon (or aluminum) to it. This is called killed carbon steel. It is still steel and it still rusts readily.

Stainless steel has a significant proportion of chromium, and often nickel as well, and sometimes other alloying materials that make it into a corrosion resistant alloy.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 19, 2009