Three key considerations for selecting geotechnical drills that maximize return on investment.
By Joe Haynes
Whether purchasing new boots or a new car, people want the most value for their money. This is especially true for drillers purchasing geotechnical drills for water well drilling, soil sampling, or standard penetration testing.
A well thought-out purchasing decision maximizes return on investment. While some consider choosing the cheapest drill manufacturer as the easy answer, price should never be the only factor.
A geotechnical drill that achieves a high return on investment withstands challenging soil conditions time and time again as well as comes with quality support from a trustworthy manufacturer.
Before purchasing a drill—consider application, quality, and service.
Assess the Application
Begin by determining which type of formations your drill crew will encounter. Water well drillers face major expenses when their drill can’t meet the challenges of their project’s location. For example, pulling a poorly manufactured drill over rough terrain can damage the equipment, which can delay a project for repairs as well as risk the operator’s safety.
Depending on the drilling formation, drill crews require either a mechanical or hydraulic drill. Each drill is suited for certain soil conditions, ranging from sand and clay to gravel formations.
Mechanical drills provide the necessary power and versatility for drilling in sand, clay, and loamy soils. These machines drill 6-inch boreholes to depths of 100 to 200 feet—tackling the scope of most water well and geotechnical projects.
Mechanical drills have few moving parts, making it easy for less-experienced drillers to operate. This helps minimize the risk of inexperienced drillers accidentally damaging the drill, and in turn, needing costly repairs. They are also lightweight and portable, so one or two people can easily load or unload the drills from the back of a truck or utility vehicle. Often, nonprofits select these for water well drilling projects in locations that have soft soil or clay, such as Guatemala’s coastal region.
However, mechanical drills aren’t the answer for every project. For example, drill crews in some areas face highdensity rock, requiring the force of a hydraulic drill. These machines achieve depths of 300 feet and are the go-to choice for operators consistently drilling to 150 feet or more.
To generate as much as 5000 pounds of pull-down force in rugged rock formations, some manufacturers offer an anchoring option and a bypass flow switch. With these capabilities, water well drill crews efficiently reach all necessary aquifers to access clean water, and geotechnical drillers reach the
required depths for attaining soil samples.
Also consider if your project could benefit with a trailermounted rig. Although these models generally cost a bit more than standard hydraulic drills, they provide a fast transportation solution and achieve depths of 400 feet. Some trailermounted rigs offer space for transporting equipment. For example, look for models with pipe racks to save on the cost of using an additional vehicle to haul drill pipe.
In addition, a trailer-mounted rig eliminates time loading and unloading the drill from the back of a utility vehicle. Some manufacturers ship the model fully assembled in a 20-foot rod rack and design it with a fold-down mast for convenient transportation.
Built to Last
Drills don’t look all that different from the outside, but look closer to find units built to last. It’s crucial to understand this when purchasing a geotechnical drill, especially when using the drill for multiple projects.
Some manufacturers entice customers with low prices by avoiding the discussion of quality, but customers soon realize those drills don’t last. When calculating return on investment, it’s difficult to see positive growth after a low-quality drill is unable to complete more projects or be resold.
Heavy-duty welded steel frames and thick drill pipes, for example, assure the drill can withstand all challenging formations. Some manufacturers cut corners on quality by constructing frames with thinner steel. This can cause the frame to bend or twist while driving over rough terrain or prematurely
wear due to corrosion in hot, humid climates.
In addition to the frame, look for manufacturers that use 2-inch-diameter drill pipe and connections made of heat-treated alloy steel. Low-quality drills generally use ¾- or 1-inch diameter pipes intended for less intense projects, like sprinkler installation.
For changing drill pipes quickly, some manufacturers offer a three-way ball valve with their drills. The ball valve allows operators to divert mudflow back into the mud pits rather than down the drill pipe. This reduces pressure on the pipe, making it easy for an operator to clamp off the drill pipe and unscrew
the drill head. It also minimizes the risk of the borehole collapse, which can be caused by cuttings flowing back into the borehole.
Drills with features simplifying maintenance make it easy for drill crews to achieve its full service life. For example, an easily accessible adjustment screw and locking nut minimizes downtime when removing slack from the drive chain. Conveniently located greasing points also save a significant amount
of time during routine greasing and maintenance checks. If maintained properly, a quality drill can last several decades.
It’s reassuring to recognize the brand of engine on a drill, too. Some manufacturers reduce costs by using small horsepower engines. This can force the engines to work harder in harsh conditions, increasing the amount of servicing and repairs. Be sure the engine comes from a reputable manufacturer by looking for features that simplify maintenance and maximize durability.
Stand by Me
Trust takes years to build and only seconds to lose. Keep this in mind when looking at the manufacturer’s commitment to service. A reputable manufacturer wants customers to succeed and has a track record to prove it. The last situation a drill crew needs is a project standstill with no one to back
them up. Conduct online research, talk to experienced drillers, and consult reviews before making a decision.
Look for manufacturers that provide training manuals, videos, and 24/7 technical support. Some manufacturers go so far as to offer training sessions at their own facilities. This is a great way for inexperienced drillers to gain hands-on experience with drill equipment and ask the manufacturer questions before beginning their project.
With these resources, drillers reduce expenses from premature wear caused by improper operation. Once drillers gain experience, it’s important the manufacturer listen to feedback for designing new drills.
From time to time, even quality drills need replacement parts such as slide pads, swivel seals, and chains. Instead of hitting a project standstill, select a manufacturer that keeps replacement parts in stock and offers fast delivery.
For overseas projects, a manufacturer’s willingness to ship parts saves on additional expenses and time from trying to find parts in remote locations. Some manufacturers assemble service kits with tools and common wear parts to prepare drill teams for the unexpected. Rather than a simple perk, this often becomes a tremendous value because it significantly reduces downtime and eliminates a trip to go looking for replacement parts.
Finally, look for manufacturers that offer a warranty, so its commitment to service is clear and supported.
Do the Math
Once your research is complete, begin crunching numbers. Given the desired application and future plans for the drill, weigh out whether saving a few dollars today by purchasing a cheaper drill pays off tomorrow.
Remember, the most drill for the dollar goes beyond the initial price tag.
Joe Haynes is president of Lone Star Drills in Livingston, Texas. Lone Star Drills are manufactured by Little Beaver Inc. Haynes can be reached at firstname.lastname@example.org.