I was recently contacted by an engineer in New England who requested a demo with one of our products. Specifically, he wanted to test Spetec PUR H100 for filling abandoned pipes. In this case, we tested the material on a 6-inch diameter PVC pipe (but any type of abandoned pipe can be filled with expansive polyurethane as long as it's 30 inches in diameter or less). This pipe was 10 feet long, but there is no real length limit using the technique I describe in this blog post.
First, we plugged both ends of the pipe. We drilled a hole in the top middle of the pipe and inserted a port. We then injected the Spetec PUR H100. For longer pipes, you would place a port every 3 feet or so. You'll also want to drill one 3/8" vent hole per 10 feet of pipe, in between ports. Of course, most abandoned pipes are located underground, so your crew will have to dig down to expose top of the pipe.