While the development of smaller more compact directional drilling units was in many ways something that the U.S. and North American market experienced for last mile applications, the use of these compact rigs has gone global. A recent project in the German the town of Schmallenberg highlights the compact directional rig’s capabilities.
The German artist Christel Lechner is well known throughout much of Europe for her life size concrete sculptures. Several of these figures are displayed throughout the town of Schmallenberg (population 26,000). One such sculpture portrays a couple reading on a bench in the middle of a traffic roundabout. Residents proposed illuminating the figures at night. The challenge was to supply power to the statues with minimal disruption to the adjacent roadway and landscaping. In order to install a power cable for the new lights, a Grundodrill 4X compact directional drill from trenchless equipment manufacturer TT Technologies, Aurora, Ill., USA, (a wholly owned subsidiary of Tracto-Technik GmbH & CO KG, Lennestadt, Germany) was used.
Compact Directional Drilling Capabilities
According to TT Technologies Directional Drilling Specialist Paul Rogers, the development of smaller drills has been going on in North America for several years. He said, “I think some of people in the industry saw this coming or at least hoped it would come eventually. Those equipment manufacturers that anticipated it really got ahead start on everyone and the equipment shows it. It is easier to use, more capable and more reliable. The Grundodrill 4X, for example, was developed by TT and has been working in North America over last seven or eight years. The expansion of the mini-drill concept to Europe was just a matter of time.
Rogers said, “These compact directionals work well in residential or commercial areas. They’re lightweight. They can be transported on a trailer pulled by one-ton truck and require minimal crews to operate. Special steel track with bonded rubber pads on many drills offer excellent traction and durability while minimizing potential damage to concrete and turf, which is important in residential settings. The technology put into today’s smaller drills has given them greater capability and made them easier to use.”
That ease of operation in some cases comes from advanced features. An available computerized Smart Vice system, for example, simplifies the drilling process by automating the drills vice cycling operations. The operator has single push button control of the function. That helps improve efficiency and speeds up drill times. The vice is also self-centering, reducing wear and tear. The operator can return to manual control with the flip of a switch.
Power is another factor. With some compact drills offering as much as 9,800 lbs of thrust and pullback, the machines are able to accomplish a wide range of installation tasks. Like its bigger counterparts, several compact directional drill rigs offer the use of drilling fluid, including various sized bentonite mixing and delivery systems. This makes compact drills effective in a wide range of soil conditions, and for a wide range of applications including sewer laterals, fiber optic cables and conduit, gas services and mains, water services and even for connections to wind power stations.
On the Job
The small, compact and power Grundodrill 4X was ideally suited for the tight working conditions in Schmallenberg. Only a small set up area was required and the lightweight drill did not pose any issues regarding surface damage to nearby landscape or green space. The drill was positioned at the power source approximately 50 m from the traffic roundabout that houses the statues. Crews began by performing a pilot bore from the street lamp (that would serve as the power source) to within a few meters in front of the statue. Once complete a 101-mm conduit was attached to the drill stem a pullback began. Once the conduit was in place, the electrical cable was placed in the conduit and the final preparations for lighting the statues were made. The drilling portion of the project was successfully completed within half a working day.
Jim Schill is a technical writer, based in Mankato, Minn.