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USA, VAnSAnt, VA

Virginia drillingIn 1998, partners Verlo Stiltner, David Hale and Mike Sheets started the contract drilling company Virginia Drilling to diversify the existing blast-ing business, Austin Sales, owned by Hale and Stiltner.

The company began as a contract driller on construction applications with Ingersoll-Rand ECM 490 and ECM 690 crawler rigs. Today the company has grown to include 28 Atlas Copco DM45’s, nine Atlas Copco DML’s and seven Atlas Copco crawler drills in various sizes, including one ECM 490 and one ECM 470 and two ECM 690’s and three ECM 720’s.

Virginia Drilling is the largest, if not the only, contract driller in the world focused primarily on the coal industry. Even the smaller construction crawler

drills are dedicated to road, reclama-tion and underground mine face-ups to a point that 85 percent to 90 percent of the work is for the coal mining com-panies.

Two years ago, the company’s co-founder David Hale passed away, but the business has continued to grow with strong leadership and committed em-ployees. Today the company has 18 drills on order and has a steady business growth plan slated for years to come.

Getting startedBecause of the existing blasting busi-ness, Virginia Drilling knew everyone in the area. Founding partner and con-struction drilling manager Mike Sheets summed it up, “the coal industry in the region is a real fraternity.” Just over a year after starting the business, which

Moving mountains

A focus on the coal industryIn the southern Appalachian range of West Virginia, Kentucky, and Virginia, known as the Blue Ridge Mountains, the seam of coal flows through the ground at varying depths, sometimes just at the base of the mountain. To get the coal Virginia Drilling Company works with their coal company partners to shave off the moun-tains one 30-ft to 40-ft lift at a time. Virginia Drilling’s business philosophy has developed over time but has remained simple, says said founding partner and company president Verlo Stiltner. “We grow the business by focus-ing on what you do best and sur-round yourself with experts.”

Virginia Drilling now has over 50 Atlas Copco drill rigs in its fleet.

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until that time had focused on construc-tion projects, Virginia Drilling partners were approached by a coal company who knew their blasting expertise and asked them to drill in the coal field.

The premise was to not waste blast-ing material on the bench, to work effi- ciently and maximize outside resources. The goal was to get costs below indus-try average and have higher drill uti-lization.

Partner responsibilities

From the beginning Virginia Drilling’s partners accepted that they were not drill experts. Admittedly, Virginia Drill- ing Chief Operating Officer Clinton Evans pointed out they had lots to learn and wanted to work closely with drill dealer Brandeis Equipment to develop a maintenance program.

“When choosing a drill it was really a no-brainer,” said Evans. They went with Atlas Copco because if its prod-uct reputation, but also they needed a strong dealer that would support every aspect of the drill including parts and support.

According to Brandeis branch ma-nager, Barry Justice, 40 percent of their parts inventory is for Atlas Copco Drills. “If the drills don’t run, the whole mi-ning process stops,” said Justice.

Brandeis has 19 service trucks in the field, running its parts department on a double shift and supplying 24/7 ser- vice to Virginia Drilling. All that atten- tion equates to a higher performance on the drills. The oldest drill in the fleet is a 1999 DML with 22,000 hours. Typi- cally on a mine site the cost of drilling equipment is approximately 5 percent to 10 percent of the total expenditures. This is another reason why some mining companies don’t focus on their drilling.

Virginia Drilling knows that the ex- cavation equipment can catch up to them but can’t pass them.

Atlas Copco regional sales manager Tom Borer said, “Virginia Drilling has drills with 20,000 hours on them that run better than drills owned by others that have 10,000 hours.”

There is no big secret here; it’s all in the preventative maintenance (PM) pro- gram. The main pumps, for example, average 7,000 to 8,000 hours for most, Two Atlas Copco DML drill rigs prepare for the next shot that will lower the bench to the coal seam.

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while Virginia Drilling averages 11,000 to 12,000 hours. It’s not uncommon for Virginia Drilling to get 40 percent gre- ater life out of their drill compo- nents because of the PM program.

Mike Sheets said, “It’s all about ta-king away problems.” Brandeis takes the burden of maintenance away from Virginia Drilling and Virginia Drilling takes away the burden of drilling and blasting from the coal companies.

He emphasized that his customers’ focus is to move material. They don’t want to worry about getting the shot right or all the liability that comes with explosives.

Sheets said, “If everyone focuses on the part of the business that makes them money everyone wins, and if we’re not drilling holes, we’re not making money.”

To ensure they are drilling holes they follow the PM program religiously. If a drill is close to a scheduled PM and a Brandeis truck is in the area, they will perform the service rather than let it get behind. As a contract driller for many mining operations in the area, Virginia

Drilling takes total responsibility for the drilling and blasting operation. The agreement with its customers is a win-win for everyone.

When this part of the business began and the deal was laid out for the custo-mer, he didn’t believe it. “He told us it seemed too good to be true,” said Sheets.

They proposed a sliding scale based on 50,000 to 1 million yards of shot material with discounts built in for vo-lume. Virginia Drilling guaranteed the product amount in the customer’s time-frame. They absorb most costs related to putting the product on the ground, from equipment to human resources to blasting material.

“When we finished making our proposal the first response was ‘where do I sign,’” said Sheets. Today Virginia Drilling s client list is long and growing.

training equals success

People are a critical part of making this work. At any one time Virginia Drilling has seven to eight drill trainees, with

that number going as high as ten. The training program has developed over time to what it is today, a well executed system. For the first two weeks they mostly watch and listen. They learn how to set up on the bench, put the mast up and down and terminology. They learn by watching and listening.

“We prefer they don’t even come in with experience,” said Evans.

They don’t want new employees to have bad habits and to learn drilling according to the company’s operation. After they have a couple weeks with the best drillers they come in for class-room work. They learn down pressure, rotation, penetration rates, bit perfor-mance and compressor and engine ope-ration, everything they need to know about the drill and what its responsibil-ity is for drilling the hole.

Then the trainees go back in the field with the experienced driller again to apply the classroom work. Every month drillers are evaluated to make sure they are getting optimum production, maxi-mum penetration and bit life

Shouldering the burden for the coal companies. From left: Mike Sheets, Clinton Evans and Verlo Stiltner of Virginia Drilling.

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and overall efficiency. But, all the as- pects of training come right back to keeping the drill working at its maxi- mum performance rate.

“We expect to get 30,000 hours from our drills,” said Evans.

The drillers have to be doing their job correctly to ensure that level of equipment life.

Performance for results

Drill performance also factors into how Virginia Drilling bids a job. “Every-thing is evaluated when looking at the cost per foot,” said Sheets. “Because we look at all aspects of the drilling and blasting process, we know how to find our efficiencies.”

One drill site may run into five dif-ferent layers of sandstone in a mine. Laminated charts plot out the geology of the mine. The goal is to get the maxi-mum penetration in relation to the time in the hole.

“The bit is an integral part of the ope- ration,” said Evans. Bits give you the data as to how the drill is performing. Weight and rotation is applied to the bit according to the situation. In this area a driller may expect to get a penetration rate of 6 feet a minute at 165 rpm and 15,000 lbs.

Although bits have an optimum ro-tation rate its only half the equation. “We are not willing to sacrifice a drill to drill faster,” said Clinton Evans. Vir-ginia Drilling looks to maximizing the relationship of down pressure to rota-tion rpm to ensure the life of the drill.

Using 7 ⅞-inch to 9-inch bits on its DML’s and 6 ¾-inch to 7 ⅞-inch bits on its DM45’s, operating between 2,500 to 4,000 hours a year, Virginia Drilling projects 2 ½ million yards of rock a month. It is expected that each drill is responsible for 500,000 yards. The DML’s are equipped with 6 ¼-inch x 30-ft pipe, while the DM45’s run 5 ½-inch x 30-ft pipe.

Virginia Drilling can move drills if needed, and to meet the required ton-nage they will run three to four drills per site at one time with a maximum of five.

Evans prefers the DML because it is beefier from the frame up, but the per- formance and hole sizes dictate what drills will be used. It goes back to blasting – try to make the pattern smal-ler but get the most value from the caps, primers and explosives.

Generally, hole spacing is on an 18-ft x 18-ft pattern. The 7 ⅞-inch hole can support 16-ft to 18-ft spacing, while the 9-inch hole can do a 19-ft to 21-ft spacing. Virginia uses a 70/30 ANFO emulsion blend as an explosive.

Acknowledgements

This article first appeared in Atlas Copco Mining & Construction maga-zine No 2 2008. Story and pictures by Scott Ellenbecker, Ellenbecker Communications.

Blasting off the top – benching down to the coal that can be seen at the base of the mountain.