World Record HDD installation of 24-inch Fusible PVC™ pipe - Iselin, New Jersey
A world record was set in the horizontal directional drilled (HDD) installation of 24-inch Fusible PVC™ (FPVC) completed at a length of 5,363-feet. Mears Group, Inc., working with Middlesex Water Company and Northeast Remsco Construction, Inc., accomplished this complex installation under the Raritan River in Iselin, New Jersey. This project utilized FPVC pipe, supplied by Underground Solutions, Inc. (UGSI), and marks another record for an installation of this type of product pipe.
This new water line installation replaced an existing cast iron water line. For this installation, Mears utilized two drilling rigs on the crossing, the 140,000 lb. and the 880,000 lb. drilling rigs. The 140,000 lb drill unit performed drilling of the pilot hole with the use of a Drillguide GST (gyro) system for the first portion of the hole due to needing to case the near surface section and ferrous debris in and along the river edge. The 880,000 lb rig was utilized for the reaming and pullback of the pipeline.
A 42-inch casing pipe was installed due to the entry’s proximity to the river edge and shallow depth of cover on the proposed line. Mears installed the casing pipe through rubble and concrete debris at the entry site. Once complete, the casing was cleared and centralizers installed to initiate pilot hole drilling. When the pilot hole reached approximately 700-feet, Mears switched from the GST system to its Para-Track II system combined with a pressure probe. Switching steering tools was due to the concern of exceeding overburden pressures and wanting to monitor the annular pressures in order to minimize inadvertent returns of drilling fluid escaping into the river.
The pipe lay down area was only long enough to allow pipe strings to be fabricated up to a maximum of 1,500-feet long. So four pipe strings were required meaning three tie-in fusion welds had to be completed by UGSI during pullback operations. The pipeline from the lay down area to the HDD exit point where it entered the HDD bore involved suspending the pipeline over a road and supporting it as it traversed a steep hillside with numerous elevation changes. Northeast Remsco Construction proficiently handled the pipeline using cranes and track hoes.
[return to top]
