Welding & Joining formula solvers
Carbon Equivalent (IIW)
Welding & JoiningThe International Institute of Welding's screening number for weldability: every alloying element on the mill certificate converted into the amount of carbon that would harden the steel as much, then added up. It feeds a code's preheat table. It is not itself a verdict on anything.
Cooling Time t8/5 (Thick Plate)
Welding & JoiningThe seconds a weld spends falling from 800 °C to 500 °C — the range in which austenite decides what it is going to become. This is the number that actually governs the hardness and toughness of the heat-affected zone, and it is what heat input, preheat and thickness are all really arguing about. The three-dimensional form, for heat running away into thick plate.
Fillet Weld Capacity from Throat Area
Welding & JoiningThe load a fillet weld can carry: the allowable stress on the weld metal multiplied by the area of the throat resisting it. A fillet weld is checked in shear on its throat whichever direction the load pulls — that is the convention every structural code shares.
Fillet Weld Effective Throat
Welding & JoiningThe shortest distance from the root of an equal-leg fillet weld to its face — the plane the weld actually fails on. It is the leg size multiplied by 0.707, and using the leg where the throat belongs overstates the weld by 41 per cent.
P_cm Cracking Parameter (Ito–Bessyo)
Welding & JoiningIto and Bessyo's 1968 composition parameter, fitted to cracking tests on low-carbon steels rather than to hardenability on the higher-carbon steels the IIW expression came from. Carbon is weighted far more heavily relative to everything else, which is what makes it the fairer screen for a modern microalloyed grade.
Weld Deposition Rate
Welding & JoiningHow much weld metal an arc actually lays down per hour: the cross-section of the wire times how fast it is fed, times the density, times the fraction that survives as deposit rather than leaving as spatter, slag or fume. The number that turns a welding procedure into an estimate.
Weld Metal Volume, Single-V Groove
Welding & JoiningThe cross-sectional area of a single-V groove — the root gap's rectangle plus the two triangles the bevel opens up — multiplied by the length of the joint. The starting point for every consumable estimate and every argument about bevel angle.
Welding Heat Input
Welding & JoiningThe energy the arc delivers into every millimetre of joint: volts times amperes gives the power at the arc, arc efficiency takes off what never reaches the plate, and travel speed divides it over the length welded. The one number every welding procedure specification records, and the one most often mistaken for a verdict on the weld.
Wire Feed Speed and Welding Current (Burn-Off)
Welding & JoiningThe relation that ties wire feed speed to welding current on a constant-voltage machine: a term proportional to current for the heat delivered at the arc, plus a term in current squared for the resistive heating of the electrode extension. It is why longer stickout gives more wire at the same amps — and less penetration.