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Pipe Reaming

Pipe reaming is a trenchless method that removes the host pipe while at the same time installing a new replacement pipe. Pipe reaming can be used to replace various types of existing pipes and is particularly well suited for replacing and upsizing pipes in stiff soils and rock where pipe bursting may not be an option. The new pipe is typically a thermoplastic pipe suitable for installation using directional drilling equipment. A directional drill is used to insert a drill string through the host pipe to be replaced. A specialized reaming tool and the replacement pipe are then attached to the drill string before the directional drill back-reams through the host pipe – enlarging the hole while grinding up the existing pipe. The fragments of the host pipe along with other cuttings are suspended in drilling fluid and are pushed ahead of the reamer through the existing pipe to a recovery pit or manhole where they extracted, separated and disposed. The new replacement pipe attached to the reaming tool is pulled in as the reamer advances.