Preheating by Gas Cutting Torch

Preheating of Steels in Welding is being carried out sometimes. This preheating is done to achieve

- To aid the fusion of welding
- To remove the moisture
- To slowdown the cooling rate
- To reduce thermal gradient difference
- To reduce the HAZ hardness
- To reduce the HAZ width
- To minimise the risk of Hydrogen crack
- To reduce the distortion

Preheating can be applied in many ways such as Preheating Torch burners, Induction heating, Thermocouple Heating, etc

However the Preheating SHALL NOT be done with Gas Cutting Torch. WHY???!!!

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