Preheating Temperature Determination

The calculated or empirically determined minimum temperature of the parent material before welding begins, used to reduce the cooling rate and prevent microstructures that promote cold cracking.

Preheating is important so that the material doesn't cool too fast during welding, which can cause stresses or cracks. If you weld too cold, the structure can become hard and brittle. But if you preheat too hot, you can temper the material or ruin its properties. The right temperature depends on the material and wall thickness; you have to take the specs from the sheet manufacturer or the welding procedure. It's important to apply heat evenly over the whole weld zone, not just spot heating.

MetallurgieSchweißtechnik