A Quick Guide to Finding the Right Drilling Rig
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Water Wells
When you’re drilling wells for water, location is everything. Generally speaking, “East and west of the Mississippi the demands on a rig change drastically,” says Brock Yordy, product manager and drill trainer for GEFCO, an Astec Industries Company.
In Michigan, for example, he says the average water well is quite shallow, around 120 feet down, whereas a lot of the western United States consists of rock and it isn’t uncommon to have to drill to depths of more than 6,000 feet to reach water. Taking that into consideration, looking into a used water well rig for work in the Midwest is totally sensible. Head west and the stress on a rig increases, meaning buying new could be a worthwhile investment.
Although going brand new can cost more than $1 million easily, the perks can be especially useful for rigs that deal with tough geologies and experience high rates of wear and tear. “You have a warranty on it and so your cost of ownership other than the monthly payment is pretty much capped. And even once the warranty expires, your cost of maintenance for the first five years on a new machine is relatively low,” says Tom Moffitt, business development manager of Atlas Copco Drilling Solutions, Deep Hole in the U.S.
As for leasing, Moffitt says a lot of people in the water well market confuse it with renting. He hears from drillers wanting to “lease” a drilling rig for just six months, making it hard to find a financial institution to help finance. Another point he makes is that truck mounted drills have to be licensed and titled, and short term deals complicate that process.
Geology matters in terms of features to focus on as well. Yordy says safety has been a major theme for the past couple of years, so rigs without catheads are in. The deeper you have to drill, the more pieces of drill rod necessary and the more important this innovative quality becomes in shrinking jobsite liability.
Once the local geology has been determined, Moffitt says relevant attributes to look for are pretty straightforward. If drilling 500 to 1,000 feet down in rocky places, he suggests looking for a rig with an air compressor. In coastal areas, where soils are sandy and holes are shallow, a mud rig or hollow stem machine is ideal. As for combination areas or overburden and rock, combination machines are a smart option. Drilling rigs like these come with an air compressor and mud on board, or they have the capabilities off board to add them.
Geothermal
Generally, water well and geothermal drilling tend to intersect quite a bit, but differences do exist, and reliability is especially important in this market. “You need a high producing machine that’s not going to be breaking down and having down time because if you’re doing a big commercial geothermal job or you’re doing wells or boreholes for a school or hospital or something like that, you have kind of a timeline that you’re working on for the project,” Moffitt says.
For this reason, Yordy says brand new rigs are ideal and leasing is a great option for drillers who suddenly win a contract for a large scale project with an established timeline. Leasing contracts can be formed to offer all of the benefits that buying new does, including warranties, services and maintenance. If you don’t already have a set of brand new geothermal drilling rigs to drill a bunch of boreholes and you aren’t sure if or when the next large scale opportunity will come around, leasing offers peace of mind and means you don’t have to store and pay off the impractical equipment once the project’s over.
As for everyday residential jobs, Yordy says geothermal is a good market for buying used. After all, the borehole depth, around 500 to 600 feet, is pretty straightforward and consistent. “A rig that used to be 100 percent efficient, if it’s 65 percent efficient and it’s a cable drive and it still can drill 300 feet pretty easily or 400 feet pretty easily, they’ll use it,” he says.
In thinking about rig features, something geothermal makes a lot more of than water wells is mud. Yordy says a lot of drillers in this market go with a rig that weighs less than 50,000 pounds and has an all-wheel drive function so they can maneuver jobsites without getting stuck. Other qualities to avoid getting stuck in the mud include six-by-six trucks — larger than typical six-by-four water well trucks — and trucks with short wheel bases.
Foundations
Similar to commercial geothermal drilling, the foundations market faces high pressure to be unwaveringly efficient. The choice between buying used, new or leasing is really specific to each end user’s needs, according to Ed Radford, director of commercial operations at Watson Drill Rigs. He says the risk in buying used is that determining how much life is left in the machine can be more challenging.
Risking reliability might not be the best route, as speed is everything to the drillers and clients in this market. “In the foundations industry, you’re in the critical path from the start of the project,” Radford says. “So if you are falling behind on production you affect the entire project and there’s potentially, in some cases, liquidated damages associated with that.”
With schedule and time being of the utmost importance, Radford recommends purchasing very productive machines, several machines or several very productive machines. The speed of the rig, the reliability of the rig, and the availability of parts and service for the rig are important features to consider.
Another aspect to keep in mind when tracking down rig qualities is space. Yordy, who’s worked with a company drilling foundation holes in the locker room of a college football stadium, says finding a drill that can fit into and function in the space in need of services is crucial. Carefully considering if it needs to be truck or track mounted to travel through a given site, and sizing the rods based on overhead clearance are key.
Geotechnical
The geotechnical drilling market is just as focused on speed as foundations. Yordy says he’s never seen a leased geotechnical rig and he doesn’t suggest buying used. “They’re usually owned by construction companies that are always buying capital equipment anyway, and so they want to go with what’s easy to maintain and what’s going to work and when something’s depreciated out they get the next piece of equipment.”
Maneuverability matters for geotechnical drillers. If you’re planning a lot of work along the highway, checking for salt intrusion for example, truck mounted rigs are the most sensible. For work around, say, a gas station, Yordy recommends a remote track mounted system. As for drilling methods, auger and sonic are two of the most effective ways to go if sampling.
Mining
Within the mining sector contractors traditionally buy new or lease to own rigs if they are intended for large projects, according to Todd Courtney, business line manager for blasthole drills at Atlas Copco USA. For relatively small jobs, like a road cut, or if they don’t own the right equipment, he says it’s common and practical to rent the drill and return it after completion.
A new rig is particularly ideal for mining because jobsites are often rife with hazards and avoiding them is very important. Older rigs don’t promise to meet the latest safety inspection standards, so keeping equipment updated is ideal or you risk not being able to even get the drill onsite.
Keeping with safety, key qualities to look for in a drill include cages around the rods that spin in the top head and hands free rod loading functions.
The scope of work you plan to do largely determines what machine is right for you. Unlike water wells and geothermal, which can more or less be tapped into anywhere, Yordy points out that Mother Nature has placed precious metals in very interesting places. If you’re going to be drilling 6,000 feet, he suggests automated rod handling with every bell and whistle that’s possible. If you’re planning to drill into the mine from the side of a mountain then it has to be very portable since getting it there could require flying it in with a helicopter. In this case, he says to just look for the basics that would make the rod spin and provide good rotational torque for getting to the required depth.
For blasthole mining, Courtney suggests finding a drill that will allow you to drill projects with single path. “If you can avoid changing steel in production drilling, there’s a lot of benefit,” he says. Because there is such a wide variety of mines, he says it’s important to determine what size holes you plan to drill and what kind of material you’ll be drilling into when drill hunting. The harder the rock, the more air pressure necessary.
Exploration
Gregory Guillot, global product manager for capital equipment at Boart Longyear, says the purchasing method for a drilling rig in the exploration market all depends on the contractor. Buying brand new is smart for a financially strong drilling company with visibility over the long run. For drillers with less of a sense of where they’ll be, say, a year down the road, Guillot suggests buying used to avoid the risk associated with the bigger investment of brand new. It’s most economical to rent, he says, if a specific job comes up at a specific location that’s well defined in time.
Exploration drilling, according to Yordy, seems to have more stringent expectations regarding minimal invasiveness than production sites. “It seems like mineral exploration is not as favorably viewed upon as when we say ‘Hey, we’re going to drill for water and when we leave you’re going to have a new source of life,’ or when we drill for geothermal we leave and we go, ‘We’ve made it so you don’t have to use as much fossil fuel and you’re going to save money.’ ”
That said, surface exploration very much revolves around keeping everyone around the jobsite happy. That means the drilling rig needs to be as clean and pristine as possible. Drilling can, of course, be quite loud, so noise mitigation is important. A quieter rig, even if it needs to be customized, is a great idea.
Another quality to look for in an exploration rig is a sliding angle mast if you’re going to be drilling angle holes, Moffitt says. He says he knows of contractors that get away with using drilling rigs purposed for water wells for exploration, but without a sliding angle mast, they’re limited to vertical holes.
Primary Percentage Rule
No matter the market, finding the right drilling rig and selecting the best purchase option are key steps in building a strong business. It all comes down to what’s most practical for the driller’s wallet, the kind of drilling being done and the geology of jobsites.
A lot of drillers, understandably, have an unrealistic image in their heads of a multipurpose drilling rig that can transcend all drilling markets, soils and depths, Yordy says. “What these guys need to think about is, do I invest $750,000 that’s going to do most of my work, or do I try to buy a $1 million plus piece of equipment in hopes of a couple extra jobs?”
Knowing the scope of one’s work and finding a rig that meets it is the safest, smartest way to go. Yordy advises drillers to go by a simple rule to stay practical and prosperous.
“What they need to do is they need to think about 75 or 80 percent of what their primary business is and look for a rig that’s going to do that.”
Valerie King is associate editor of National Driller.
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