Welding automation

[maxim10373]

Hello everyone
Can you tell me what type of welding is used here as seen in this video? How much kva power is required to spot weld up to 4 mm?

 

[D.A.(Tony)Stewart]

Assuming;

The specific heat of steel is 420 J/(kg°C)​

Plain steel has a density of around 7.85g/cm³
Estimating temperature rise of about 2500 °C
Estimate 4 mm cubed = 0.064 cm³
Compute the energy [J]
Estimate the rise time in temperature.
Compute the Power [J/s]
Estimate resistance vs temp

Compute the current.​

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