As a wireline engineer, we all know that each operation has its own set of challenges, and while we strive for flawless execution, things don’t always go as planned. I want to share a story from one of my recent jobs—a lesson learned the hard way involving the pre-job cycling of wireline valve rams. This incident led to a severed wireline, and as we dug deeper into the issue, we uncovered some critical lessons that every engineer in the field should take to heart.
The Incident: Severed Wireline in the Greasehead
It was supposed to be a routine operation. The wireline was being run into the well, with everything proceeding as expected. However, as we reached the next step of the process, something unexpected happened. We had followed all the necessary procedures: we applied grease between the rams, bled off the lubricator with no pressure present for over an hour, and then proceeded to slack off the wireline so that we could disconnect the union above the rams.
But when we lifted the lubricator from the wireline ram assembly, the crane operator noticed something strange. There was no additional resistance in the lift, which was originally expected to indicate that the wireline was free from the greasehead. However, when the lubricator was lifted a few feet, we discovered that the wireline had been severed near the top of the wireline rams assembly.
Upon closer inspection, we identified the root cause: a small piece of metal lodged in the wireline alignment groove of the upper ram. This metal piece caused the wireline to be forced into the opposing steel body of the ram, resulting in the severed cable. What we didn’t know at the time was how that set screw ended up in the alignment groove.
The Mystery: How Did the Set Screw Get Lodged?
The investigation into this problem led to a few theories about how the set screw became lodged in the ram. While we considered several possibilities, including the chance that the set screw had backed out of the toolstring, we quickly eliminated that option. After examining the entire toolstring, we found no matching components for the set screw, making it unlikely that it had come loose during the job.
Another possibility was that the set screw might have been overlooked during the annual inspection and pressure testing of the pressure control package. We had replaced the rams, and the equipment had undergone a redress and visual inspection just 27 runs prior to the job. However, we ruled this out as well because any damage to the test rod would have been detected during the inspection.
The most likely explanation, though, was that the set screw had entered the alignment groove during the pre-job cycling of the rams. This is the step where the rams are checked to ensure they open and close properly before the operation begins. Typically, a test rod is used during this process, but in this instance, the test rod wasn’t available. A scrap piece of wireline was used instead, and it was during this step that the set screw became lodged in the alignment groove, causing the wireline to become severed.
The Lesson: The Importance of Pre-Job Cycling
This incident taught us some valuable lessons about the importance of pre-job cycling for wireline valve rams. The rams are an essential part of any wireline operation, whether you’re performing cased hole logging, production logging, or well perforation services. Ensuring that the rams are properly inspected and tested before every job is crucial to maintaining the integrity of the operation.
One of the key takeaways from this incident was the need to stress visual inspections of the rams—not just checking them in the open and closed positions, but also thoroughly inspecting the components for any signs of wear or foreign objects. In wireline operations, we work with a wide variety of tools, from perforating guns to wireline control systems, and each component must be in top condition to avoid any misruns or failures.
Prevention: How We’re Ensuring This Doesn’t Happen Again
In response to this incident, we’ve implemented some new practices to ensure that this kind of failure doesn’t happen again:
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Visual Inspection: We’re making it a priority to perform a more thorough visual inspection of the rams during every pre-job test. This includes checking not only the rams in the open and closed positions but also inspecting the grooves and other critical parts for any debris or damage.
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Using a Test Rod: We’re ensuring that a test rod is always available for the pre-job cycling of the rams. If for any reason the test rod isn’t available, we’ll use a scrap piece of wireline to perform the cycling test. This ensures that we’re not missing any potential issues that could arise during the operation.
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Clear Communication: If there’s any uncertainty about the procedure or equipment, we’ve learned the importance of contacting the management team immediately. Waiting for a solution could result in costly mistakes, so we’ve instilled a policy of addressing any uncertainties quickly and effectively.
The Bigger Picture: Why These Practices Matter
This experience has reinforced the importance of using the right tools and following the best practices in wireline operations. Whether you’re involved in wireline perforating, downhole pipe recovery, or cased hole wireline services, attention to detail is paramount. Tools like the pipe caliper tool, wireline truck, and wireline perforating guns all play critical roles in ensuring the success of the operation.
By continuously improving our wireline service practices and incorporating lessons learned from past incidents, we’re able to provide better service to our clients and improve the safety and efficiency of our operations. As wireline service providers, it’s our job to stay ahead of potential issues and keep our equipment in top shape, ensuring that every job is completed with the highest standards of safety and precision.
Conclusion: Commitment to Continuous Improvement
In the end, this incident served as a valuable lesson about the importance of thorough preparation, attention to detail, and proper tool management in wireline operations. Whether we’re performing logging operations, conducting perforating services, or ensuring well integrity, we need to ensure that every component, from the wireline unit to the perforating system, is ready for the job.
By taking the lessons from this experience and implementing new best practices, we’re able to deliver complete wireline solutions that meet the highest standards of performance and safety. As wireline technologies continue to evolve, we remain committed to staying at the forefront of the industry, always looking for ways to improve and refine our practices to ensure the success of every well operation.