Recording Extreme Bakken Mill Times

Small-time energy services provider, Extreme Energy Services LLC, has recorded some impressive mill out times of fracture sleeves and composite plugs with an in-house design. Extreme's success shows how small teams can have huge Bakken results.
By Luke Geiver | April 21, 2014

The Remi mill is named after a Louisiana toolmaker’s dog. The mill was designed, in part, by Jesse Crone, regional manager for Extreme Energy Services LLC, to speed up milling times for horizontal laterals in the Williston Basin. EES formed in 2010 and also serves other oilfields in Texas and Louisiana, but is best known for its growing portfolio and case studies from the Bakken. Although it took Crone and his team a few months to gain client approval for the Remi mill’s use, the design work and explanation efforts put forth by the team to clients have paid off. EES has grown from a four-person operation to a milling specialist that runs more than 14 technicians while turning away client requests for more milling services.

Originally, Crone and his toolmaker wanted to call it the scallop mill based on the mill’s head characteristics, but the name just didn’t do justice to the unique design. In fact, the mill’s design didn’t resemble anything the two had seen before. “The design that we came up with on that mill is a little outside of the box of what a lot of people were drilling their sleeves with,” Crone says. Many mills resemble a honeycomb shape formed to fit into a specific pipe size.

When a Williston Basin well is completed using ball seat and sleeve or a composite plug method, a mud motor powering a mill head is used to mill out the sleeves or plugs post fracture. Typically, the seat and sleeve or composite plug manufacturing company will recommend a particular type of mill most suitable to remove its products. The mill design offerings are vast, ranging in size and shape. After analyzing the performance of his team’s drill outs, Crone recognized a troublesome pattern with several of the mills. “We would consistently see the same type of wear on the mill every time it came out of the hole,” he says. After tweaking the design of the Remi mill three times based on the research and analysis of completed milling jobs, Crone is now confident in deploying the mill to drill-out sleeves anywhere in the Williston Basin.

Making the Mill
When Crone arrived in Glendive, Mont., six years ago he had $120 in his pocket. He didn’t have a place to stay or a job lined up. He was 19 years old, his girlfriend was back home in Minnesota and his knee was still recovering from surgery. “When I tore my ACL [anterior cruciate ligament] I didn’t have health insurance. The surgery cost $21,000 and the quickest way to pay it back was to move to the oilfields and work,” he says. “I went to Glendive to pay off medical debt. I didn’t have intentions to stay in the oilfields forever.”

Today, Crone is the regional manager of Extreme Energy Services, a job he earned after six years employed on a workover rig. He recently built a new house in Dickinson, N.D., for his girlfriend-turned-wife and his two daughters to live in. “Moving to the Bakken was the greatest thing that could have happened to us,” he says. And, for EES, it might just be Crone’s willingness to endure long hours on a workover rig or performing mill-outs. Working with his team on mill-outs inspired Crone to work with his toolmaker on the Remi. The success of the Remi has helped EES land jobs once reserved for major service providers like Baker Hughes.

When the design work first started, the premise was simple: Find a way to mill out sleeves near the toe of the lateral as quickly as those near the heel. According to Crone, other mill designs were working great, but only near the heel of the lateral. “Towards the end of the well further out in the lateral you would start to see slower drill times,” he says.

To alleviate the slower times, the EES team designed a mill that offers a new, fresh milling surface as the motor pushes the mill further away from the heel. In a lateral section of a well, the ball seats and sleeves get smaller closer to the toe, so, to match the decrease in well bore size, the Remi was designed to offer a smaller cut face for the smaller well bore sizes, a process that creates a new cut face suitable for each sleeve still present in the wellbore. As each new cut face is exposed during the mill-out process, the time required to mill-out sleeves near the toe of the well matched those closer to the start, or heel, of the well bore.

Using the manufacturer recommended mills, Crone says, the average drill-out times with a standard sleeve would come in between 8 to 12 minutes per sleeve for those closer to the heel. But, towards the end of the milling process, mill times per sleeve would increase to 45 minutes to 1 hour due to the wear on the mill cutting face.

“With the new Remi mill, the consistency remains in that 8 minute to 12 minute range throughout the entire well bore. So, if you look at the entire well bore and you knock off 45 minutes on 8 sleeves to 10 sleeves, you are knocking off 8 hours to 10 hours per job,” Crone says.

The EES team is currently on job 1,843 (each job is numbered and the team started on job 1,000). Of those jobs, 600 were performed using mills. Because of the experience EES has had using mills—on the composite plugs or sleeves—the team has been able to analyze what performs best. “The Remi mill has sold itself now,” Crone says, “based on the performance of it.”

Although EES offers several downhole services, its ability to perform mill, outs with one motor and one mill in quicker times compared to competitors has pushed the team to focus heavily on milling and drill outs.

“The name of the game in our business is simple. When you go on a job after the frack job is completed, you go in with one motor and one mill, and you want to be able to drill out a full lateral without pulling out of the hole,” Crone says. “If you have to pull out of the hole and change tools, it costs a significant amount of money.”

Because of the Remi’s design to offer a new cutting face, it has kept the team’s toolmakers busy, and, it has put a major emphasis on the quality of the mills made for EES. All of the downhole tools are certified by a third-party, and without quality tools, Crone says the business would struggle.

The changing completion methodologies have also made the entire team thankful for the Remi mill. Today, most wells are completed using more than 25 discrete fracture stages, a practice requiring more sleeves and composite plugs than ever before. The team is also excited about the multi-well pad approach to oil production. The Remi can bring wells on production quicker than the competition in many cases. “If they [industry] wouldn’t have changed over to these long laterals and the use of composite plugs and sleeves, we wouldn’t have business,” he says. But, thanks to a torn ACL and a dog named Remi, the mill out business for EES is good.

Author: Luke Geiver
Managing Editor, The Bakken magazine