HDD Drilling Topics
November 1, 2009
Auger Boring Record Set by Perco Engineering ServicesPerco Engineering Services Ltd., Northampton, England, installed 17 under-track rail crossings (UTX) in Nottinghamshire, in what is considered the largest single auger-boring project ever undertaken in the United Kingdom.
The UTX installations were required to enable power cables to pass under a double-track railway line, connecting a new power station to the national grid.
Using two Bohrtec BM 400 auger rigs, Perco crews worked out of two separate concrete launch pits, which were 100 feet long and 23 feet deep, allowing a depth of 16 feet from rail track level to the plane of the guided auger bore shots.
Spaced 10 feet apart, nine shots were made from the first pit, with eight being made from the second. Each shot installed nearly 100 feet of 18-inch OD clay pipe, ready to accept the client’s MDPE ducting to carry the power cables. Perco then grouted the annulus between the clay and MDPE pipes.
Ground conditions varied across the 17 auger boring operations – from heavy clay soils to sand and ballast. Crews worked around the clock, 7 days a week, and carried out all lifting operations. Although delays were encountered, the project was completed in 5 weeks, and with no interruption to rail services.