Preheat for Plasma Cutting
Preheat for Plasma Cutting
(OP)
I have noticed in D1.1-2000 there are not references to preheat in plasma cutting, yet we are referenced by engineering to preheat any material above 3/4" by using the Section 3 requirements of preheat for welding.
I have not worked anywhere that there was any preheat requirements for plasma cutting before now. Does anyone have any information to share on this?
I have not worked anywhere that there was any preheat requirements for plasma cutting before now. Does anyone have any information to share on this?





RE: Preheat for Plasma Cutting
Your engineering department may be taking a conservative approach based on past experience. Some undesirable microstructures can result along the cut edge as a result of rapid cooling. The problem is exacerbated as the carbon equivalency increases and the thickness of the base metal increases. Members that will be hot dipped galvanized are a concern because of cracking issues related to the carbon equivalence and the potential for hard microstructures that can result when high strength low alloy steels are thermally cut.
Best regards - Al
RE: Preheat for Plasma Cutting