Tortuosity has changed the way that people look at production, Rob Shoup, Gyrodata’s Operations Technical Support Manager, explained at WorldOil’s live Artificial Lift Forum on Tuesday, February 12th. He covered the topic: “identifying wellbore tortuosity for production equipment placement and optimization”.
“Tortuosity is basically a deviation from a straight hole,” Shoup said. Tortuosity can significantly impact drilling processes and efficiency. As a result, it is a crucial factor for the design and installation of completions and production equipment because a highly tortuous wellbore section can exert strong bending forces on drilling equipment. It can also cause high friction on moving parts.
Gyrodata has the ability to do an analysis of geometric tortuosity. Clients are able to see large-scale information anywhere from 200 to 500 feet course lengths. “We are able to analyze the well on a small scale at a one-foot interval so we can actually see the geometric shape and changes and do an analysis of the wellbore. This is extremely helpful.” Shoup said. After a high-resolution log is run, data can be analyzed at every foot. Such data will typically show that there are a lot of anomalies that are not caught with just the drilling survey. “I can’t tell you how many times I’ve heard operators say that a well is vertical when, in fact, it is not.” Shoup said.
Gyrodata had one client that started using our data to quantify whether or not there was value in putting wells back online. They identified that it was a worthwhile endeavor to run the service, do an analysis on it, and then make an educated analysis as to whether or not that well would be profitable in the future. Shoup explained.
Aside from doing a tortuosity analysis, Gyrodata is also able to analyzed effective diameter. “The effective diameter is defined as the maximum diameter of a straight cylinder that can be inserted into a given section without distorting it.” Shoup said. For a short section of casing, our analysis can tell exactly what the diameter is. If an individual wants to run a 120-foot electric submersible pump (ESP) into a wellbore, Gyrodata is able to do an analysis there and tell them whether or not that pump is going to fit, be straight or whether it is going to bend, Shoup explained. “Not only do we look at effective diameter, but we also look at the effective diameter allowing for a uniform bend. We can actually define the amount of bend that the pump is going to see at any given point in the wellbore.” He said.
Shoup spoke of a case study where a high-tortuosity log improved ESP placement in the Permian Basin, which is located in Texas and the southeastern part of the U.S. state of New Mexico. An operator had experienced four failures over a six-month period. They had determined that it was heat and vibration from friction that was basically causing failures in pumps. They also had damaged cables when they were inserting it past 7,700 feet. A high-data density log identified that there was a highly tortuous area that was not originally detectable. Ultimately, in this particular wellbore, the ESP and a bean pump were ruled out due to the tortuous areas that were damaged down past a certain area in the vertical portion of the wellbore. A gas lift was the only option. However, the problem was in that particular field, the client was not set up for a gas lift, Shoup said. If the client had known this from the beginning, they would have saved more than $700,000 in lost cost due to the production lost from the tortuosity.
Shoup concluded the presentation by saying that high-resolution data analysis provides benefits for rod-guide placement. Drilling surveys do not provide enough granularity for ESP placement analysis. Also, high-resolution data is essential. It provides a better picture of what’s going with a wellbore.
Gyrodata’s MicroGuide specifically provides detailed tortuosity and obstruction analysis to identify the best possible placement of artificial lift equipment. It also delivers high-accuracy measurements and high-resolution imagery to improve modeling calculations and drilling engineering, such as torque and drag calculations, bottom hole assemble modeling and true vertical depth corrections. MicroGuide generates customized well insight and analysis reports, including three-dimensional visualizations and standard traditional log format presentations.