Steel Preheating Calculator
Calculate preheating temperature according to EN 1011-2 based on chemical composition, thickness, and hydrogen content.
What is preheating?
Preheating is heating the base material before welding to reduce the cooling rate of the weld and heat-affected zone (HAZ). This helps prevent cold cracking (hydrogen cracking) and improves weld quality.
🌡️ Preheating Temperature Calculator
Calculates the required preheating temperature according to EN 1011-2 (Method B) based on chemical composition, material thickness, hydrogen content, and heat input.
Steel Chemical Composition [%]
Technological Parameters
Heat Input Parameters
Why is preheating important?
Prevents cold cracking
Slower cooling rate reduces the risk of hydrogen-induced cracking in steels with elevated hardenability.
Controls microstructure
Prevents formation of hard, brittle martensite in the HAZ.
Standards compliance
EN 1011-2 and ISO 15614 require documented preheating for certain materials.
Hydrogen diffusion
Higher temperatures allow hydrogen to diffuse out of the weld before it causes cracking.
Frequently asked questions
Preheating is required when carbon equivalent CET exceeds approximately 0.35, material thickness is greater than 25mm, or when using welding consumables with high hydrogen content.
CET = C + (Mn+Mo)/10 + (Cr+Cu)/20 + Ni/40. This is the formula according to EN 1011-2 considering main alloying elements affecting hardenability.
Tp = 697·CET + 160·tanh(35/d) + 62·HD^0.35 + (53·CET - 32)·Q - 328, where d is thickness [mm], HD is hydrogen content [ml/100g], Q is heat input [kJ/mm].
HD means diffusible hydrogen content in weld metal expressed in ml/100g. It depends on welding process and condition of welding consumables.
Preheating reduces cooling rate, which prevents formation of martensitic structures and hydrogen (cold) cracking in the heat-affected zone.
The main standard is EN 1011-2 - Welding. Recommendations for welding of metallic materials. Part 2: Arc welding of ferritic steels.
Manage welding professionally
WeldStack is a complete platform for welder records, ISO 9606 certificate tracking, WPQR/WPS documentation management.