Underground Construction - August 2022 - 15

AUGERBORING
Modern Guidance for Auger Boring
Matches Growth of Technology
Jeff Griffin | Senior Editor
Horizontal auger boring equipment was
making trenchless installation beneath
roads, highways and other obstacles for
years before the term " trenchless technology "
came into use.
Early auger bores were unguided.
Because they were relatively short, they
didn't have much length to wander from
their path, as long as soil conditions were
suited for boring. However, as longer
bores became more practical and appropriate,
it was obvious that a method to
maintain the proper line and grade of the
insulation was needed.
Today, the use of guided auger bores
is increasing. Underground Construction
asked leading manufacturers to explain
how their guidance system operate and
have addressed the requirements of
longer bores, sometimes in difficult soil
conditions.
MV Solutions
Vermeer MV Solutions Business Development
Manager Dave Gasmovic
said auger boring is one of the oldest
forms of trenchless technology for underground
utility installation work. But
initially, the machines lacked the ability
to accurately make steering adjustments
while in the ground.
Guided auger boring solutions to address
this were developed in the 1980s,
expanding the capabilities of auger boring
machines.
" The use of auger boring, in general, "
he continued, " is growing as municipalities
upgrade their storm drainage infrastructure,
sewer systems and water lines.
In many cases, they turn to auger boring
because it's less invasive than excavating,
and the machines can install casing ranging
from 20 to 72 inches in diameter and
up to 600 feet in length. "
Together, these factors have made it
necessary to use guidance systems, Gasmovic
believes.
First, the amount of existing infrastructure
has increased. Also, there is a
tendency to set manholes before the boring
process. Casing must be installed at a
certain grade and online. The demand for
greater distances also has increased the
need for accuracy to reduce auger friction
and allow longer bores to be made.
Any time that a pipe needs to maintain
a specific grade or line, a guidance
system should be used on auger boring
projects. The most common products
that require lines and grade to be maintained
are gravity sewer and storm sewer
systems. But many contractors will employ
guidance systems anytime they are
boring 100 feet or more, because being
slightly off at the start of a bore can have
major implications at longer distances.
Gasmovic said the McLaughlin
On-Target Steering (OTS) system has
grown in popularity. It can be paired with
any brand of auger boring machine to
help maintain line and grade. Bores can
be made in a single pass using an auger
boring machine and OTS system; using a
pilot tube system requires multiple passes.
" With the OTS system, " he said, " the
auger boring machine is placed in the
entry pit, and a control station is put next
to it. A steerable cutting system, matching
the size of the casing being installed,
is then welded to the first casing, and the
first auger section is bolted to the steerable
head's cutter.
" Four hydraulic lines are then connected
from each steering flap on the
steerable head to the control station.
These lines are connected to the top of the
steerable head, and a cover helps protect
the connections. A water line is run from
the control station's recirculation tank to
the steerable head for real-time accurate
grade reading. An optional electrical pitch
UCONonline.com | AUGUST 2022 15
http://www.UCONonline.com
Underground Construction - August 2022

Table of Contents for the Digital Edition of Underground Construction - August 2022
