Compact Focus: Compact directional drills
| June 12, 2007 |
The move into the compact directional drill market is a natural one for contractors in the plowing and trenching business. Compact HDD units can be used to install drop work, gas service, water lines, fiber-optic cables or other utilities from the curb to a house or small business, and there’s an obvious synergy with trenching and plowing operations.
Relatively speaking, compact directional drill rigs are an inexpensive way to break into the HDD market, says Ed Savage, underground market segment manager, Vermeer. “Moving into directional drill work is a natural evolution for many contractors engaged in more conventional utility installation methods,” he says. “And the market has also evolved in such a way that they need to go the directional drill route to remain competitive in their markets.”
This is because of customer demand for installation methods that don’t disrupt lawns, sidewalks or roadways, and also because HDD drop work can be highly profitable due to the short bores and quick installation jobs these compact rigs excel at. In most cases, drill rigs up to 10,000 pounds pullback are most effective on bores out to 300 feet in length.
Financial success for compact drilling operations normally depends on the number of drops you can do a day, Savage notes. So high production, compact drill designs and easy transportation are key characteristics for rigs in this class. “Production with these machines is really all over the place,” Savage says. “In many cases, the number of existing utilities in the ground is the main deterrent limiting the number of drops a contractor can complete in a day. Some contractors are satisfied doing three or four drops a day. Others do as many as 12 to 14 a day, depending on how they’re laid out. The key is planning the day in advance and being as quick and productive as possible with the drill.”
Speed is critical to maintain profit margins
“Typically, when you get down into this kind of work with compact directional drills, the price per foot is lower than on jobs with larger drill rigs,” says Richard Levings, senior product manager, Ditch Witch. “Most contractors work somewhere in the $3.50- to $5-per-square-foot range. But you’re also talking about a lesser investment as far as your initial costs to acquire and operate these small units.”
Compact drill rigs, Levings points out, burn less fuel and use drill pipes and downhole tools that are less expensive than those found on larger HDD rigs. “All this adds up to lower operating costs (although your insurance costs remain about the same) and gives you a favorable profit margin at those lower rates,” he adds.
But speed is critical on these drills because the rig needs to start the bore, complete it, hook the product and pull it through and then pack up and get to the next one as quickly as possible when you’re working at those lower footage rates.
Matching the machine with the proper soil is one way to ensure fast, multiple bores. “Loam is always the best soil to work in,” Levings says. “But these rigs are also highly productive in certain types of clay and sand. Hard sand can be a little more difficult to work in, but the 10,000-pound rigs generally handle it okay. Certainly it gets to be more challenging when you get into rockier, drier or harder soil conditions.”
“One thing we did to increase productivity on these machines was go to 6-foot-long drill stems instead of 5-foot stems,” Savage says. “A foot longer stem reduces the amount of time you’ve got to make and break joints during a bore. This, obviously, at the end of a day, week or month means extra production time gained.”
Long drill stem aside, Vermeer still had to place the pipe in the shortest machine length possible. “Some of that is for ease of transport,” Savage explains. “But the main thing is, on a jobsite, you often need to back that rig up against a building to start the bore or place it and work in confined spaces. So the shorter the machine, the better you can get situated and down to business.”
If you’re hauling a compact drill rig around, Levings says you can get by with a 1-ton pickup truck because they’re so small and easy to handle. On the other hand, some contractors opt for larger tow vehicles, as large as semi trucks, largely due to the equipment they use to support the drill – usually a compact excavator or 100- to 150-gallon vacuum excavation system. “Typically, you want smaller types of support equipment to help expedite these frequent moves,” Levings notes. “You also want to optimize features on the drill itself wherever possible.”
Levings points to the back system, also known as the mud-mixing system, as a prime example of this philosophy. “Many larger HDD units use 800- or 1,000-gallon back systems,” he says. “But most compact drills can operate effectively with a 500-gallon system – so again, it’s a lower initial cost for the drill and you can transport it with a smaller tow vehicle and trailer.”