As wireline engineers, we deal with critical operations every day, and safety is always our top priority. One operation that carries inherent risks is downloading explosives from the toolstring, particularly when dealing with misruns, canceled operations, or any unexpected issues that require us to safely remove the explosives from the wellbore. Recently, we encountered an incident that involved downloading fuses and primers after a perforating job, and it underscored the importance of following best practices to ensure safety and reliability. Let me share the story and the lessons we learned.
The Incident: Safe Downloading of Explosives
We had completed a TCP (Tubing Conveyed Perforation) job and encountered a situation where we needed to safely download the explosives. As part of the job, we had to remove the fuse and primer from the firing head, which involved very careful handling of the explosives to avoid any mishaps. The task at hand was crucial, as failure to follow proper procedures could lead to dangerous consequences, including unintended detonation or damage to the equipment.
During this particular job, we encountered a misrun that required the downloading of fuses and primers. Everything was going according to plan, but there were a few additional safety checks that we hadn’t accounted for, which added to the complexity of the operation.
We had to follow the correct steps to avoid setting off any accidental detonations while retrieving the components. At the same time, the pressure to move quickly and efficiently while ensuring no mistakes were made was intense. Thankfully, we were able to complete the operation safely, but it was a close call, and it led to some critical lessons that we have since incorporated into our best practices.
The Root Cause: A Lack of Awareness of Client-Specific Procedures
In retrospect, a key issue that arose during this operation was not adhering to the client-specific procedure, which required stopping at certain depths for a fixed period. For example, we should have paused for a minimum of one hour at 1,000 feet in Texas, as per the client’s policy. This oversight resulted in a delay in identifying the fault early enough, causing unnecessary complications during the download process.
Another contributing factor was a lack of awareness regarding the handling of explosives exposed to high temperatures. In this case, the guns containing HMX (an explosive compound) had been exposed to temperatures higher than 300°F. According to our standard safety guidelines, these guns should have been set aside for 24 hours before attempting any downloading or troubleshooting. This delay could have allowed us to perform a more thorough check and identify potential issues before the explosives were moved.
Action Items: Revising Procedures for Safe Downloading
After the incident, we implemented a new set of guidelines and procedures to ensure that downloading fuses and primers in the future would be as safe and efficient as possible. Here are the key actions we have taken:
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Follow Client-Specific Guidelines
Going forward, we will adhere to all client-specific policies, including mandatory pauses at certain depths. These steps will ensure that we fully comply with safety measures and allow us to troubleshoot any potential issues at the right time and depth. Whether it’s a wireline well logging job or a TCP perforation, we must take the time to check the required parameters and adjust our procedures accordingly. -
Temperature Sensitivity of Explosives
We’ve instituted a strict 24-hour wait period for any explosives exposed to temperatures exceeding 300°F. This gives the system enough time to cool down and ensures that no explosive components are compromised by excessive heat. This additional waiting period will give us more time to address any potential issues with the firing head or other downhole tools. -
Thorough Troubleshooting and Inspections
During future downloads, we’ll follow a more structured troubleshooting process. This includes checking for any loose connections, missing components, or incorrect configurations. Every o-ring, thread, and connection is inspected carefully to ensure no issues are missed. We also take pictures of any findings to document the condition of the equipment and components for further analysis, if necessary. -
Proper Handling of Fuses and Primers
Downloading fuses and primers requires extra caution. If we encounter any difficulties with removal, we use the proper tools, like needle nose pliers with tape applied to the tips, to carefully turn the fuse until it can be removed by hand. The fuses are then securely placed in shipping tubes for inspection. For primers, we use a CT transfer sub in a vice and a flat punch to gently remove the primer, ensuring all body parts are kept away from the sub during the process. -
Clear Reporting and Incident Documentation
If any fault or issue is discovered during the downloading process, we now have a clear protocol for reporting it. All findings are documented in an incident report and communicated to the manager immediately. This ensures that all necessary steps are taken to prevent similar incidents in the future, and that any failed components are sent back to the manufacturer for further analysis.
The Bigger Picture: A Focus on Safety and Precision in Wireline Operations
This incident reinforced how essential it is to stay vigilant during wireline operations, especially when working with explosives in sensitive tasks like perforating, well logging, or pipe recovery. A wireline provider’s ability to deliver consistent, safe, and reliable services depends on adhering to established procedures, regardless of how routine the job might seem.
Whether performing wireline perforating or utilizing wireline tools such as a pipe caliper tool, logging cables, or downhole cameras, it’s crucial to follow best practices to ensure every part of the operation is carried out safely and accurately. Safety should never be compromised, especially when handling potentially hazardous materials.
Looking Forward: Continuous Improvement in Wireline Services
Wireline services, whether for production logging, cased hole wireline, or even advanced well perforation, are built on the foundation of knowledge and experience. We have learned valuable lessons from this experience and are committed to incorporating these lessons into our future operations. By following the updated best practices, implementing stricter safety measures, and ensuring that all procedures are followed meticulously, we are confident that we can avoid similar issues in the future.
Conclusion: A Commitment to Excellence and Safety
Every wireline operation, from the deployment of perforating guns to cased hole logging, requires precision, care, and a deep understanding of the tools at our disposal. The lessons we’ve learned from this incident, particularly in the safe downloading of fuses and primers, will help guide our future operations. By committing to thorough checks, proper handling, and the correct use of wireline technologies, we can continue to deliver safe, reliable, and efficient wireline services in the oil and gas industry.
This experience has made us more determined to improve our processes and provide complete wireline solutions, ensuring that every task, whether for fishing wire line or well integrity checks, is executed with the utmost care and safety.