Is 30 amp wire good enough to push a 220v welder?

If the welder does not list the input amperage, jyou can always refer back to the math that you learned in school.

A simple algebraic formula will help you figure out the amperage:

Amps * Volts = Watts

Since you already know the Volts (use 240 for calculation), you should be able to calculate the amperage that is used by the welder.

Up to about 12 Amps, use a 15 amp breaker and 14 AWG wire.

Up to about 16 Amps, use a 20 amp breaker and a 12 AWG wire.

Up to about 24 Amps, use a 30 amp breaker and a 10 AWG wire.

You should have a qualified electrical professional perform any wiring changes if you do not have an adequate circuit already available to where you will be using the welder.