T8/5 Calculator (preheat calculator)
CERTILAS Weld Analyse Pro is a detailed calculation tool designed to predict and optimize the welding quality of ferritic steels.
The calculator performs the following core functions:
- Cooling Time Calculation (t8/5) : Determines the time required for the weld metal or the HAZ to cool from 800 °C to 500 °C. This is crucial because cooling too quickly leads to brittle structures (martensite), while cooling too slowly reduces strength due to coarse grain formation.
- Heat Input Determination (Q): Based on the selected welding parameters, the calculator determines how much energy is introduced into the material. This directly influences mechanical properties such as hardness and impact toughness limits.
- Prediction of Mechanical Properties: The calculator predicts the expected hardness, tensile strength, and yield strength in the heat-affected zone (HAZ) based on the chemical composition of the steel. It also determines the tensile strength of the weld metal based on dilution between the base material and the welding consumable.
- Preheat Temperature Recommendiation:Calculates the minimum required preheat temperature to reduce the risk of hydrogen cracking and cold cracking using the carbon equivalent (CET).
- Analysis of Cooling Regimes: Determines whether the heat flow is two-dimensional (2D) or three-dimensional (3D), depending on the plate thickness and the critical thickness.
In summary, this calculator supports anyone involved in selecting the correct welding parameters to ensure that the welded joint meets the required specifications, in accordance with standards such as EN 1011-2, ISO 15614-1, ASME IX, Lloyd’s Rules, and DNV Rules.