MANUFACTURING – WELDING CALCULATOR
Interpass Temperature
A precise tool.
What is the Interpass Temperature & How does it work?
Interpass temperature is the peak temperature reached in the weld zone between two successive passes. Maintaining this temperature within prescribed limits prevents grain growth, reduces residual stresses, and ensures consistent mechanical properties.
Different base materials have distinct maximum allowable interpass temperatures. For carbon steels the limit is often around 250 °C, while stainless steels and nickel alloys require much lower limits (≈150 °C) to avoid sensitisation and loss of corrosion resistance.
The allowable interpass temperature can be estimated by subtracting the pre‑heat temperature from the material‑specific limit. This relationship is expressed by the following formula:
\Delta T_{allowed}=T_{limit}-T_{preheat}
Delta T_{allowed} = maximum permissible rise in temperature between passes, T_{limit} = material‑specific interpass limit, T_{preheat} = applied pre‑heat temperature
Parameters
Result
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Frequently Asked Questions
What is interpass temperature in welding?
Interpass temperature is the peak temperature reached between two successive weld passes. It's crucial for maintaining material integrity.
Why is controlling interpass temperature important?
Controlling interpass temperature prevents grain growth, reduces residual stresses, and ensures consistent mechanical properties in the welded joint.
What are the maximum allowable interpass temperatures for carbon steels?
The maximum allowable interpass temperature for carbon steels is often around 250°C to prevent issues like grain growth.
How does interpass temperature affect stainless steels and nickel alloys?
Stainless steels and nickel alloys require much lower interpass temperatures (≈150°C) to avoid sensitization and loss of corrosion resistance.
What are the consequences of exceeding the interpass temperature limit?
Exceeding the interpass temperature can lead to grain growth, increased residual stresses, and compromised mechanical properties in the weld.
How do I determine the appropriate interpass temperature for my specific material?
Refer to the manufacturer's guidelines or consult with a welding engineer to determine the appropriate interpass temperature for your specific material.
Can you provide a general formula to calculate interpass temperature?
While there isn't a one-size-fits-all formula, it generally involves monitoring weld pool cooling rates and using thermal imaging or other temperature measurement tools.
Results are for informational purposes only and do not constitute professional advice.