Horizontal Boring & Tunneling, of Phoenix, AZ, recently completed a 54″ diameter bore 440’ in length through hard, caliche rock. The project required a 24″ sewage line be installed under I-17 in Anthem, AZ. Horizontal Boring used a Michael Byrne Mfg. D72-1.5M auger boring machine and a 54” retractable, roller cone cutting head to complete the job.
The roller cone head features a spring-loaded overcut. This allows the cutting head to be retracted back through the casing for repair or for line & grade confirmation.
To combat the tough ground conditions the cutters on the roller cone were changed twice during the bore. Additionally, the cutting head was cooled with lubricant to prolong the life of the cutters and the bearings.
Roller cones are typically used in hard rock applications, where the rock hardness is between 10,000 – 40,000 psi.
The delivery of Natural Gas via pipelines continues to be
the most cost effective and safest delivery method. Studies continue to verify
pipelines as the safest and most environmentally safe delivery method https://www.aga.org/research/fact-sheets/pipeline-safety/. The export of LNG has recently made the
United States the number one exporter of LNG.
The export of LNG strengthens the US economy and provides a source for
our Allies to source compared to competitive nations that are not friendly to
the United States. Natural Gas is also
firing many of our electric generation plants and driving down the carbon
footprint for these institutions making electric cars, LNG vehicles, and a whole
new industry more environmentally friendly. The advances in trenchless technology
as well as tried and trusted methods like auger boring used in
conjunction with Guided Pilot Bore machines continue to make the installation
and maintenance of pipelines among the safest ways to install and transport
The American Society for Civil Engineers (ASCE) will be grading the nations stormwater for the first time in 2021! The Trenchless Technology magazine article notes that the 2017 grading of the United States infrastructure was a D+, while this sounds terrible it was improvement from the previous grading period. We need our legislature to come together and do what is best for our Country and quit backbiting each other. Using a simple A to F school report card format, ASCE’s Infrastructure Report Card provides a comprehensive assessment of current infrastructure conditions and needs and assigning grades and making recommendations to raise them. The ASCE Committee on America’s Infrastructure, made up of expert civil engineers from across the country, assigns grades using the following criteria: capacity, condition, funding, future need, operation and maintenance, public safety, resilience and innovation. Additional information regarding the Infrastructure Report Card and state report card program may be found on infrastructurereportcard.org.