NEWS FROM SPE ATCE 2013 Experts debate methods to improve well positioning
BY KURT ABRAHAM, Executive Editor
NEW ORLEANS -- The risk involved with well position calculations can often be considered difficult to quantify. Nevertheless, at an SPE Annual Technical Conference luncheon, several speakers presented their opinions on the best practices to improve the odds of success. Steve Mullin, manager of business development at Gyrodata, who was a last-minute fill-in for another speaker, led off the discussion by summarizing the situation as “Don’t be in the wrong place at the wrong time.” He went on to present his “Top 10 reasons for misplaced wells.” One of these, what he called the “Business Case,” occupied a good deal of his comments.
“One of the more aggravating factors, is when people short-cut what they should really do and try to save money,” said Mullin. “Unfortunately, saving that bit of money has severe consequences.” He explained that while industry personnel may think that they’re saving money on the front end, there can be significant negative effects in the field. Indeed, the problems range from a too-short gyro run costing a firm $10,000 in the long run, or a proximity shut-in taking $100,000 from the bottom line, to a “minor collision blowout” costing $1 billion, and a “major collision blowout” having a $10-billion effect. Another of Mullin’s Top 10 items is “Poor surveying costs production.” He said this type of situation can be summarized by saying, “Hey, we’ve lost 10% of our production in the long run, but we save the cost of a gyro.” In the end, said Mullin, “Saving money on a survey is a high-stakes gamble, which can make you famous (or infamous).”
Mullin’s five other Top 10 reasons for misplaced wells include magnetic interference acceptance criteria that are inappropriate or far too large; problems with drainage direction; drill pipe stretch not being accounted for; cheap survey programs; and poor data recording and quality control.
Neil Bergstrom, a wellbore geodetic advisor for Devon Energy, had his own thoughts on avoiding bad magnetic surveys. “Degaussing BHA components is an easy thing to do, relatively inexpensive, and can make a big difference,” said Bergstrom, who added that “drillstring magnetic interference causes azimuth error.” He outlined his own list of potential solutions to poor surveys and bad well positioning. These include degaussing; increasing the distances to sensors; using more non-magnetic materials; and making sure that steels are hard to magnetize. Also, if degaussing is conducted, it had better be a complete job, without cutting corners, said Bergstrom. “Superficial degaussing is only temporary.”
Looking at the industry situation overall, Bergstrom lamented that “there’s not enough surveys being run to ensure correct data (for well positioning).” Bill Allen a segment engineering technical authority at BP, chimed in with the thought that “it’s a shame that people can publish technically accurate data, which is nonetheless meaningless.” He was referring to personnel and firms that, with the best intentions, still manage to conduct flawed surveys and then spread around the resulting data that winds up being misleading.