They call you randomly by phone after you have applied, mainly to ensure you are interested in the job and mention the drug test screening before you get the job.
I applied online. The process took 3 weeks. I interviewed at SWP (Surprise, AZ) in Dec 2018
Interview
Easy weld test / mig t-joints all positions on 10g- 1/4 mild steel. After that the interview process lasted 20 mins tops. The job offer would have came in a few days if the shop lead didn't go on vacation.
The interview was not hard or intimidating. I was very casual. Had to go to some training prior to accepting and getting the job. Just know why you want a job at the company and you're good.