How to cut > How to preheat before thermal cutting

Preheating methods

One effective method to prevent hydrogen cracking during cutting is preheating the material. Preheating allows more hydrogen to diffuse away from the cut edge and reduces the cooling speed of the cut edge, thus minimizing introduced tensile stresses. Preheating is particularly beneficial before oxy-fuel cutting and plasma cutting with oxygen as plasma gas.

However, for all types of laser cutting and plasma cutting with nitrogen, preheating is not recommended due to its negative effect on the cut edge quality. Depending on the situation, either part of the plate or the entire plate can be heated. 

The most common ways to preheat the plate are preheating furnaces, preheating lances, and electrical mats.

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