Welding Heat Input Calculator

The Welding Heat Input Calculator finds the amount of heat or thermal energy that is introduced to a material when a weld is made using the arc voltage, current, and travel speed.

INSTRUCTIONS: Choose units and enter the following:

• (`E`) Arc Voltage
• (`I`) Current
• (`S`) Travel Speed

Welding Heat Input (`H`): The calculator returns the answer in kilojoules per inch (kJ/in). However this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

Arc voltage, current, and travel speed directly affect heat input. Heat input is often associated with cooling rates of the heat-affected zone and the weld. Heat input is also directly proportional to the individual weld bead cross-sectional size. For example, the size of a fillet weld increases as the heat input increases. 

To find the welding heat input, use the formula:

H = (60⋅E⋅I) / (1000⋅S)

where:

• H = heat input
• E = arc voltage
• I = current
• S = travel speed

Welding Calculators:

• Bend Allowance Calculator: Computes Bend Allowance based on the thickness of the material, bend angle, inside radius, and K factor.
• Weight of Aluminum Square Bars: Computes the average weight of aluminum bars based on the number and dimensions of the bar, and an average density of 2700 kg/m3 for aluminum bars.
• Aluminum Wire Deposition Rate Calculator:  Estimates the rate at which a welding wire is converted into weld metal using the electrode diameter, wire feed speed, and electrode efficiency.
• Welding Heat Input Calculator: Estimates the amount of heat or thermal energy that is introduced to a material when a weld is made using the arc voltage, current, and travel speed.
• Groove Weld Potential Root Cracking Calculator: Determines whether or not the groove weld has a potential for root cracking based on the width-to-depth ratio (1.0-1.4).
• Weight of Hot Rolled Steel Flats: Computes the average weight of steel flats based on the number and dimensions of the flats, and an average density of 7800 kg/m3 for steel flats.
• Modulus of Elasticity for Martensitic Stainless Steel: The measure of stainless steel's tendency to deform elastically when a force is applied.
• Brinell Hardness of Gray Cast Iron: Measure of gray cast iron's ability to resist permanent indentation deformation.
• Weight of Brass Rounds: Computes the weight of any number of brass round bars based on the number of rods, their dimensions, and an average density of 8,600 kg/m³ for brass.

Fabrication Calculators and Constants

• K Factor Calculator
• Aluminum Wire Deposition Rate Calculator
• Steel Wire Deposition Rate Calculator
• Welding Heat Input Calculator
• Groove Weld Potential Root Cracking Calculator
• Weight of Hot Rolled Steel Flats
• Modulus of Elasticity for Martensitic Stainless Steel
• Brinell Hardness of Gray Cast Iron
• Bend Allowance

References

Tools for Reviewing Welding Procedures (https://app.aws.org/mwf/attachments/11/253611/TOOLSFORREVIEWINGWELDINGPROCEDURES.pdf)

Bridge Welding Reference Manual (https://www.fhwa.dot.gov/bridge/steel/pubs/hif19088.pdf)