WorldWide Drilling Resource

7 SEPTEMBER 2021 WorldWide Drilling Resource ® Who Ya Gonna Call? PIPE BURSTERS! Adapted from Information by TT Technologies, Inc. The scene is the Lower Rhine town of Korschenbroich, lying between the metropolitan areas of Mönchengladbach, Krefeld, Neuss, and Düsseldorf in the west of Germany. Korschenbroich retains its countryside character in spite of a growing population, with approximately 68% of the total area used for agriculture, and just under 22% for residential, commercial, and transport areas. The rest is recreational, forest, and water areas. Sounds idyllic - but there were problems. The public corporation Erftverband operates a sewage pumping station (pump house and rainwater overflow basin) in the Korschenbroich region of Liedberg. The pumping station transports dirt and rainwater through an approximately 2800-foot-long pressure pipe along the main road, then via a canal to the wastewater treatment plant in Glehn. But after about 40 years in operation, the pressure pipe urgently needed renewal. Due to aging and strong roots growing into the pipe, it had rough cracks, connection and socket damages, as well as damages caused by corrosion. Increasing leakages regularly caused flooding on the adjacent properties of local residents. There was something weird happening in the neighborhood, but Erftverband knew who to call: Pipe Bursters! After consulting with an engineering firm for a pipe renewal plan, they contracted to complete the job using the following guide- lines: utilize the closed, trenchless construction method of pipe bursting and upsize the diameter of the pipe by two nominal widths. There were two main reasons for the plan, said Gerhold Alfes, managing director of the pipe bursting company . . . “an old asbestos-cement pressure pipe ND 150, where it would make great sense to leave this in the ground, [and] secondly, a larger diameter was required in the course of the renewal for hydraulic purposes, which is part of the technology and easy to implement with pipe bursting.” With the first section previously completed, the team placed the GRUNDOBURST ® 800G in the nearly 15- by 7-foot-wide starting pit along with the magazine of Quicklock bursting rods, ready to continue the renewal. The rig pushed the rods smoothly and quickly through the old pipeline, using Quicklock link coupling and positive force transmission to prevent the rods from slipping back. Pulled by a hydraulic pipe bursting unit, the cutter head’s unique bladed cutting wheel design actually split the host pipe instead of ripping or tearing it like single fin-type static pipe bursting systems. An attached expander spread and displaced the split pipe into the surrounding soil, while simultaneously pulling in the new pipe. The existing bore path was expanded to about 10 inches to accommodate the new nearly 8-inch pipe. After four and a half hours, the second section of the pressure pipe was renewed. With success on these sections, finishing the job with the application of the static pipe bursting method using the GRUNDOBURST 800G proved to be the correct remedy for this leaky, old pipe-renewal task . DIR