transformer questions

Greetings all,

I'm looking for a pole pig now and have some questions that I would like
to know the answers to.  

1) Has/does anyone run a coil without any limiting ballast on the pig?
   In other words, has anyone cut the welder and oven elements entirely
   out of the circuit?

2) Will these transformers blow up if they get shorted without any control?

   I already have an arc welder that I am going to use, but I am asking 
   because one of the guys that my wife contacted wanted to ask me some
   saftey questions and I figured that I should know as many angles as
   possible.  (It's not a surprise, but will be a great birthday gift :-))