摘要 |
An improved method for replacing existing underground sewer pipe is accomplished without excavation, pipe bursting, or pipe reaming. First, vertical sight holes are drilled into the ground and through the existing pipe. Slurry material from the vertical hole drilling fills the old pipe. Then, a pilot hole is drilled in a first direction through the old pipe. Then, a reaming tool is pulled in the opposite direction so as to enlarge the pilot hole and grind out the old pipe, while simultaneously pulling the new pipe into position behind the reaming tool. The broken old pipe and slurry are vacuumed out of the vertical relief holes. |