In the oil and gas industry, the need for reliable, efficient, and innovative technologies has never been more pressing. Engineers often find themselves grappling with a variety of complex scenarios—from deep wells and high-pressure environments to limited access locations and wells prone to debris or turbulent flow. Each of these unique situations presents its own set of challenges, especially when it comes to setting a tubing anchor catcher (TAC).
Traditionally, the process of setting a mechanical TAC requires several rotations at the tool to fully extend the slips. Documented setting and releasing procedures, like those available from TechTAC®, explain the process this way:
Once the desired setting depth in reached, rotate the tubing to the left (to the right if the TAC is right-hand set) until the slips contact the casing (approximately 6-8 turns for the 7” and 5.5” TACs).
While this setting method has been effective for standard operations, there are scenarios where it can be especially challenging. For example, extremely deviated wells can make it difficult for those surface rotations to reach the tool. That’s where the concept of a quick-setting tubing anchor – an anchor that requires only 1-3 turns to be fully set – comes into play.
The idea of a quick-setting tubing anchor isn’t just about speeding up a routine task; it’s about optimizing performance in specialized conditions. Petroleum engineers often face situations where the conventional methods are not only inefficient, but potentially risky as well. This article explores distinct use cases, showing why quick-setting anchors are more than beneficial; in some scenarios, they’re essential.
Use Case 1: Quick-Setting Tubing Anchors in Deep Wells
Deep wells present a unique set of challenges when it comes to setting anchors. The depth of the well itself can make it difficult to generate enough torque at the surface to set the anchor securely. Additionally, the longer the tubing string, the more likely it is to experience significant torsional wind-up, making the setting process even more complicated, especially in grades of steel that exhibit reduced torsional rigidity.
A quick-setting tubing anchor that requires only 1-3 turns would be beneficial in these environments. Not only would it reduce the time and effort required to set the anchor, but it would also minimize the surface torque required to do so. This device could significantly enhance the reliability and safety of operations in deep and deviated wells where additional torque is required to overcome drag.
Use Case 2: Wells with Extreme Wellbore Geometry
Certain drilling conditions can cause a borehole to develop high dog-leg severity or take the shape of a corkscrew. Trenchlesspedia defines dog-leg severity as the “measure of the change in direction of a wellbore over a defined length, normally measured in degrees per 100 feet of length. The more severe a dogleg is, the more potential difficulties arise due to the drill string passing through a curved well trajectory.” Similarly, a corkscrew well – one that spirals downward – can also create downhole challenges.
Traditional tubing anchors can be very difficult to set in wells with these types of extreme wellbore geometry. The directional changes within the well make it difficult to apply the necessary string torque to reach 6-8 rotations at the tool. A quick-setting anchor overcomes this obstacle by reducing the amount of string torque required to fully set the anchor.
Use Case 3: Horizontal Wells
The number of horizontally drilled oil wells in the United States continues to rise. According to the U.S. Energy Information Administration, “In 2021, 81% of U.S. well completions were horizontal or directional, as opposed to 19% of wells that were drilled vertically.” With this change, the need for quick-setting tubing anchors is rising as well. Like the challenges inherent in deep wells, setting a tubing anchor in the bend of a horizontal well can make it difficult to generate enough torque at the surface to set the anchor securely. Setting the TAC in 1-3 turns is much more practical in horizontal wells than the 6-8 turns required by a traditional anchor.
What About Tension Anchors?
Some operators have preferred to use tension anchors in use cases like those noted above. The category of tension anchors includes most quarter-set and hydraulic tubing anchors. These tools do not require rotations to set them.
While tension anchors can be a valuable alternative in some downhole assemblies, they do come with certain limitations. Most notably, tension anchors are usually not “catchers.” When a tension anchor is fully set, it will hold the tubing securely, as long as the tubing is firmly attached to the wellhead. If the tubing breaks, parts or is disconnected, a tension anchor will not stop it from falling down the well. A tension anchor can withstand tens of thousands of pounds of upward pressure before it shears, but only a relatively small amount of downward pressure can send the anchor down the casing.
In addition, the purchase price as well as the maintenance cost of a tension anchor can be significantly more than a quick-setting TAC. For example, many well repairs do not require the replacement of the production tubing and anchor. If just a rod, valve or surface equipment need to be replaced, the entire production string may not need to be pulled. However, with a tension anchor, once the upward pressure is released, that anchor disengages. In contrast, a quick-setting tubing anchor catcher would keep the production string in tension while the repairs are made.
The Slimline® QuickSet™ Tubing Anchor Catcher
To address these and other use cases, TechTAC® introduced the Slimline® QuickSet™ TAC. This quick-setting anchor can enhance the performance and design of many downhole production strings. The Slimline® QuickSet™ TAC provides all the same benefits as the original Slimline® – such as up to 245% more flow-by area – but with the added ability to set the slips in just 1-3 turns. Leveraging the Slimline® QuickSet™ TAC in challenging well scenarios allows operators to set the anchor with minimal surface torque, while still enjoying the Slimline’s unique ability to minimize the formation of scale, iron sulfate and paraffin. Minimizing these elements helps reduce the occurrence of stuck anchors and gas locked rod pumps.
The concept of a quick-setting anchor offers distinct advantages in a variety of well scenarios. It’s not just about ease; it’s about enhancing safety, efficiency, and reliability. For petroleum engineers tackling challenging well operations, choosing the Slimline® QuickSet™ TAC could be a game-changer. To learn more or to get a quote, contact the TechTAC® team today!
