Yep, they even sell a special device for that now, and it's basically just a welder. The only problem is that most pipe used underground is some form of plastic these days. I never used a welder, so I am going to ask. Dont the welder transformer overheat? Those devices made for the purpose pulse on and off from what I heard, althought I neve used one of them either. Most of my plumbing work was in the city and a heat gun was the usual fix.