Microtunnelling projects often encounter a variety of complex challenges that can prove costly and push out project delivery timelines. However, contractors with versatile equipment can easily adjust to unexpected issues – by changing drilling heads, and being able to install a wide range of pipe materials and diameters – to ensure a project is delivered on time and on budget.
When working with versatile equipment, contractors are able to adapt and adjust their approach whilst using their knowledge around the existing ground conditions and their equipment, to dramatically reduce risk in a microtunnelling project.
Versatility is especially important given the geotechnical information provided at the start of a project isn’t always 100 per cent accurate, and contractors often arrive on site to find different conditions than anticipated – with unexpected ground conditions a common reason for project delays or installation failure.
Visual inspections with AXIS
Even in cases where contractors can’t predict what lies beneath them, they can be assured that with the right equipment at their disposal, they can get the job done, despite unforeseen issues.
For example, the AXIS laser guided boring system is a versatile pitch-launched microtunnelling machine, designed to provide contractors with a versatile solution that combines productivity, accuracy and efficiency.
Rather than jacking into unconfirmed ground conditions, which can be risky, the AXIS uses vacuum extraction to perform a pilot line, allowing the contractor to visually inspect the ground and select the best drill head for the prevailing ground conditions, before committing to jacking the final line.
Changing ground conditions and the air hammer
Another factor for contractors to consider are ground conditions, which can cause major issues during microtunnelling projects. Different ground conditions – such as varying soil types, groundwater conditions, the presence of rock and debris, and fractured rock and sand – require different drill heads and approaches.
This means an unexpected change to the ground midway through jacking can be time consuming and costly, as most machines are only designed to move forward and the drill head will need to be dug out from above in order to change it.
The AXIS system has the unique ability to retract. This means any changes in ground conditions not picked up by the pilot line will not cause a problem as the drill head can be retracted and swapped out with minimal time wasted and with no additional cost.
Furthermore, very hard rock conditions are no longer a challenge, no matter if it is known before a project or partway through the drill. The air hammer is a drilling tool that provides microtunnelling contractors with a solution for very hard rock conditions, increasing rates of successful pipeline installation, while still maintaining accuracy, productivity and efficiency.
The technology uses air-driven hammers (similar to vertical DTH heads) on the AXIS laser-guided system or AdaptX – manufactured in Australia by Bournedrill, part of OptionX Group.
Riteline and the accuracy of trenchless installation
A new spacer innovation from OptionX Group that is purpose-built to improve the accuracy of trenchless pipeline installations, Riteline casing spacers assist the carrier pipe during installation by maintaining its position relative to the bored hole or encasement pipe. The spacer’s design means its height can be adjusted from 30mm up to 125mm, allowing multiple configurations from the one unit.
Riteline’s adjustable design means contractors who use them don’t need to have multiple products on hand – they can be installed to suit the project’s needs, even if requirements change at the last minute.
Unlike other spacers on the market, they are also spring-loaded, which means you can adjust the tension as required, and they flex when they hit rock – so they won’t break. This also removes the issue of them floating when grouting takes place.
AdaptX – variety of options in the one machine
Most drilling machines are only capable of utilising one or two drilling techniques. However, there is a new drilling machine on the market that boasts capabilities that are unmatched across the globe. AdaptX is a modular drilling platform that allows the contractor to use most drilling techniques all in the one machine, including: vacuum, pressure air vacuum, slurry, HDD, displacement pilot, auger boring, bed boring, box culvert jacking and canopy tunnel drilling.
This gives contractors more options for different methods all in the one machine, allowing them to not only take on more jobs but be flexible on the job site if unexpected circumstances occur to ensure the best method for the job is used.