Barbco Inc. unveiled its new FlexBor system in May at an open house event in Pennsylvania. Now the technology has two successful projects under its belt to highlight the boring tool.
The FlexBor system features an encased bore that virtually eliminates the threat of frac out and can be used in combination with typical horizontal directional drilling (HDD) surface-launched equipment or pit-launched using auger boring methods. The system uses air flow to remove spoil, eliminating the need for slurry and reducing disposal costs. The pit-launched system can reduce the entry angle associated with longer HDD crossings, thereby reducing the length of the bore.
The FlexBor system has been in development over the past several years, with product developer Derik Engle working with East Canton, Ohio-based Barbco to refine and test the tool. Engle developed the system as a result of shortcomings he experienced trying to install pipelines with a mid-sized rig.
“We were encountering problems with HDD because the radius needed to complete the project made it too long for the equipment,” Engle said. “So, I started digging launch pits to shorten the bores, then we started using different cutting tools and air pressure to remove the spoils.”
The FlexBor system is available in two configurations, a static type that allows for shallow boring depths with minimal cover, as the drive casing also serves to carry spoils typical of traditional cased bores; and the larger auger type that allows 100 percent of the boring machine’s rotary torque to be applied to rotate the FlexBor tool around its internal auger to help convey and mix the spoil into the drive casing.
The FlexBor system was trial-tested on two recent projects in Ohio to install gas pipelines. The first was a project for Buckeye Partners in Findlay, Ohio, going under Interstate 75. The other was for Rice Energy in Belmont, Ohio, crossing Bend Fork stream. Both projects used the static type FlexBor system in conjunction with Barbco’s hybrid Tribor machine, which combines guided boring (pilot tube), HDD and auger boring.
Barbco worked with Columbus, Ohio-based Kirk Excavating Inc., which was contracted by Buckeye Partners to install an 8-in. steel pipeline under the highway in western Ohio. Kirk Excavating used a pit-launched FlexBor system with a Tribor machine. The contractor cut a 11.5-in. hole with an entry pit at 16 ft deep and the exit pit at 7 ft deep. The project team navigated clay and dirt soil conditions and completed the 250-ft project on April 1, using a 385-cfm compressor and 2 gpm of water, with no additives.
One of the main challenges for the project team was that Buckeye would not allow for a void under the road. Auger boring was deemed risky because of the small diameter and existing utilities in the bore path. Using the FlexBor system allowed for casing or pipe to be under the road at all times.
Key project personnel included Derik Engle, product developer/site manager; Richard Bradley, Tribor operator; Tony Barbera, Barbco owner; J.D. Smith, Barbco field technician; and Chuck Kirk, Kirk Excavating owner.
“This project was ideal for using the FlexBor System due to gas company restrictions on standard HDD methods,” Barbera says. “The project was to install the product under I-75 in Findlay, Ohio. The restrictions were in place that a void could not be under the road at any time. The FlexBor system uses casing to hold and remove the cuttings, which allowed for a continuous presence under the road until being replaced
The pilot hole was placed with precision using a dual-rod camera system, known as guided boring method (GBM), in lieu of walk-over locating system. The FlexBor system was able to accommodate the project restrictions barring tradition HDD methods.
“The use of Barbco’s Tribor and FlexBor systems allowed this project to be completed by the specifications without inadvertent returns and a small footprint,” Barbera adds. “In addition, this job was completed using less than 350 gallons of water with no additives.”
Barbco worked with Millstone, West Virginia-based B Miller Excavating Inc., which was contracted by Rice Energy to install a 12-in. steel pipeline under a stream in eastern Ohio. Like in the Buckeye project above, B Miller also used a pit-launched FlexBor system and Tribor machine on the Bend Fork stream crossing section of the “George to Athena” project, which included a 440-ft bore through rock and fractured rock soil, under an environmentally sensitive waterway, with a 1,200-ft bend radius and entry and exit pits at 6 ft deep.
Key project personnel included
Engle, product developer/site manager; Bradley, Tribor operator; Smith, Barbco field technician; Brian Miller, owner/contractor; and Chris Seymour, on-site environmental inspector.
Because the 12-in. steel gas pipeline was being installed in an environmentally sensitive area, the project included a number of restrictions. After Engle completed a site survey, the Barbco team determined the job represented another prime opportunity to showcase the new FlexBor system, based on the environmental sensitive area.
“Restrictions were in place that no additives could be used to complete the drill,” Barbera says. “This included not only the typical additive of bentonite, but also included water. During Derik Engle’s site survey, he identified the water tables at the site, prior to any drilling activities. The pits were then dug accordingly and the bend radius was established to meet the needs for the project.”
The project was completed June 13, using only ground water and air pressure in accordance with environmental guidelines. The FlexBor system was able to accommodate the restrictions that traditional HDD methods would not allow.
Barbera added, “The FlexBor system prevented inadvertent returns with use of casing to harbor cuttings even with the minimal ground cover required for this project.”
In addition, the FlexBor system required only a pilot hole and one pass of the FlexBor head to complete the desired hole diameter of 18 in. All equipment had to be barricaded in with plastic to avoid environmental concerns. The combined use of Barbco’s Tribor and FlexBor systems allowed this project to be completed within the environmental specifications and a small footprint.
Barbco has been working with other contractors to use the new FlexBor system on other projects through the Marcellus and Utica shale regions in Ohio, Pennsylvania and West Virginia. The company expects to launch the auger type FlexBor later this year.