My maintenance crew recently discovered that someone drove a rebar through a sewer pipe during construction. Obviously this causes problems. The rebar in nearly dead center of the pipe which is encased in a concrete floor. Any ideas to remove the rebar with out breaking up the floor? There is access from the outside about 10-15 feet from the rebar. Thanks.
They make root cutters for cutting plant roots that have grown through pipes, but they are made to cut roots, not steel. I'm not aware of anything that is specifically designed for this. Maybe you could get a steel cutting blade made for a root cutter. You would then still have to get the pipe lined afterwards to seal the holes. This would be a pretty difficult and expensive process, and it would not be guaranteed to work.
Overall, it will probably be the best and cheapest option to cut the concrete around the pipe, fix it properly, and replace the floor. If the repair blending in is of concern, you would want to cut at existing saw joints, if the concrete will be covered, you can just cut and replace the immediate area of the repair.
While you might be able to find a specialty coring outfit that can cut the rebar without damaging the pipe, I suspect that their cost is going to be higher than just busting out the floor/ digging around the pipe/ removing the rebar/ sleeving the pipe to repair/ filling and patching.
Unless you can pin this on someone with insurance, I'm afraid you're on the hook for this.
Repair of collapsed or corroded cast iron sewer pipe under concrete slabs is done where I live by either cutting through the slab or by tunneling under the slab.
You could try cutting it out with a diamond wire saw. I have seen them slice right through tower block pillars (concrete and rebar). If you could loop the wire over the rebar and keep it flush to the side of the pipe it would cut though easily. There are hand saws available (basically just a diamond coated wire with loops on each end). The other option might be an angle grinder on a long pole.
Then you'd need to repair the pipe using CIPP or similar. Good sewer CCTV companies should be able to help with that.