spot welding transformer parameter

[maxim10373]

What is the parameter for 2+2 mm (SS) rod spotwelder transformer ?
10kva is inough ? how to calculate the transformer ampere ?

please help

Maxim

 

[dick_freebird]

Based on casual use of a small spot welder I would recommend an empirical approach, there are variables to the process including prep, force, material and desired service duty factor.

 

[Warpspeed]

All of the above + time.

Most welding processes become much more controllable and repeatable from a stable current source. MIG welding being a notable exception.

Something that tends more towards having a higher impedance constant current output rather than a very low impedance constant voltage output. High impedance being relative of course ! !

The traditional method for making a constant current transformer is to place a shunt magnetic air gap between primary and secondary. In the case of the ancient "buzz box" stick welder, the shunt gap is adjustable with a slider rod. Something like that perhaps, but wound with a much lower secondary voltage.

The key to transformer design is deliberately increasing the leakage inductance by reducing the direct primary/secondary magnetic coupling. Windings side by side, not one on top of the other.
Even better with a deliberate shut magnetic path around the primary.

 

[rogerryan]

What is the parameter for 2+2 mm (SS) rod spotwelder transformer ?
10kva is inough ? how to calculate the transformer ampere ?

please help

Maxim

Simply you can use this equation to find out amper of spot welder

A=KVA x1000/v