Drilling advances

Being attentive to signals that the well emits during drilling can save a world of headaches and money at the end of the day. Certainly, that counsel is as time-worn as rotary drilling itself, but some say it may be well worth remembering now, more than ever, especially with the unconventionals, where the primary focus is repeatability and getting to TD and online as quickly as possible.

Analyzing trend lines from even basic real-time or near-time analytics, such as BHA and top drive torque response, or comparative analysis of RPM against flowrate and weight-on-bit (WOB), could sidestep a host of drilling hazards that, at best, increase the risks of non-productive time (NPT), but, at worst, lead to severe well control issues. Consequently, today’s high-octane industry could be served well by stepping back with a bit of historical perspective, said Pat York, Weatherford’s global director of well engineering, project management, during the most recent Technology Forum of IADC’s Drilling Engineering Committee (DEC).

“Thirty and 40 years ago, we always paid close attention to the health of the wells as we drilled them,” he said. “Now, we see some of those talents being lost, or put on reserve, because we’re trying to drill faster and deeper, and get from spud to spud as quickly as possible. Sometimes, we’re betting that we know what’s happening in the well ahead of time, because of our experience and, therefore, we’ll drill these wells very efficiently every time.”

“We’re not saying that you shouldn’t drill deeper, cheaper and faster. But, if you’re not paying close attention to the quality of the well and maintaining wellbore stability, with about five out of 10 wells, you may have to throw some money in the ground by drilling a sidetrack, because you lost a BHA.”

Given the contemporary economic climate, where cost-consciousness reigns just below HSE in the priority hierarchy, York said cost-saving analytics can entail the simple evaluation of incoming data sets to see how they are trending over time. “You can start to see alerts that will let you know, well ahead of time, when things are starting to go south on you,” he said. “Unfortunately, sometimes when we’re drilling these wells so fast, we lose sight of that and we don’t need to.”

In a real world example, Weatherford’s Chuck Salminen, a senior drilling optimization engineer, told the DEC how monitoring an unconventional well forewarned that actual torque data were starting to “veer away from the planned data.” As the well was being drilled extremely fast with a high rate of cuttings being generated, Salminen said he quickly suspected a build-up of drill solids.

“When I saw this developing, I told the driller and directional driller that we might be getting cuttings accumulation around the BHA. They said they were supposed to be pumping sweeps, but hadn’t in a few hours. They pumped a sweep, circulated bottoms-up twice, and the actual torque values came down to plan (values),” he said. “So, here we saw the direct response of behavior of incoming data coming back to plan.”

He also recommends monitoring continue, even after TD, citing an instance where severe lost circulation had been encountered and mitigated while drilling the well. The completions team may not have been aware of the lost returns, and with no monitoring taking place after TD, the production string became differentially stuck. After a series of over-pulls and slack-offs, the pipe eventually parted, and some 700 ft of casing was left in the hole. “They had to sidetrack and re-drill the entire well. With the tight spacing on these pads, there are concerns over wellbore collisions and where to place the well,” he said. “So, the point is, this (monitoring) service can be applied further down the line, and it doesn’t have to end at TD.”

Political deafness. The DEC also heard how Ohio’s newly re-elected Republican governor, John Kasich, came off much like a driller tuning out a chatty well, when he ignored a groundswell of support and put the kibosh on a federally sanctioned Utica shale drilling program. Jeffrey Daniels, director of the Subsurface Energy Resource Center (SERC) at Ohio State University (OSU), said days after the fully vetted Utica Shale Energy and Environmental Lab (USEEL) was awarded a nearly $7-million federal grant, OSU was ready to bring in a drilling contractor, when Kasich surprisingly vetoed the research and community engagement project.

“We had a great plan, and when we submitted the proposal, we had absolute buy-in from the state,” Daniels said. “We had a dedicated, 760-acre site in prime Utica country that we (OSU) had both the surface and mineral rights to. The project was vetted with our Department of Natural Resources, top to bottom. It had everyone’s full support. Then came the election. We had an RFP ready to give to a drilling contractor, and the governor said no.”

The now-suspended plan Daniels referenced was for one of three field drilling laboratories that the U.S. Department of Energy (DOE), through its National Energy Technical Laboratory (NETL), authorized in early November. Along with OSU, West Virginia University (WVU) was awarded a grant for a Marcellus shale field lab, and the Gas Technology Institute was sanctioned to study fracing inefficiencies. The DOE said the purpose of the drilling program, which it hopes to extend to other shale plays, is “continued research to promote environmentally prudent development of unconventional oil and natural gas.”

Now it’s back to the drawing board, as the principals continue to seek the governor’s buy-in. “These labs were approved to help industry increase productivity, but also demonstrate the effectiveness of emerging environmental impact mitigation technologies,” Daniels said. “Also, this project provides a great opportunity to communicate and better interface with the public.”