If there’s one thing wireline perforating teaches you, it’s that every component in a perforation job must be perfect. A misfire, a failed detonation, or an unintended event can cost time, money, and, most importantly, safety.
One day, we almost ran a recalled A-140S blasting cap into the hole—a mistake that could have led to serious consequences.
The Setup: A Standard Wireline Perforating Job
We were gearing up for a cased hole perforation in a high-pressure gas well. The job was straightforward—pump down perforating, using A-140S blasting caps to initiate the perforating guns.
We went through our usual pre-job checklist:
- Toolstring verified.
- Control fire switches tested.
- Ground continuity checked.
- Blasting caps visually inspected.
Everything seemed good. We were minutes away from running in the hole.
The Last-Minute Save: Catching the Recall Notice
As I was double-checking the equipment, I glanced at the lot number on one of the A-140S blasting caps.
It looked familiar. Too familiar.
Something clicked in my memory—Austin Powder had issued a recall on certain A-140S caps earlier that year. I quickly pulled up the recall bulletin and checked the date shift codes.
The caps in our perforating guns were from January 2014 to March 13, 2014—right within the recalled batch.
We had almost sent a recalled detonator downhole.
The Immediate Action: Preventing a Potential Failure
Once we realized the issue, we:
- Stopped all operations immediately.
- Removed all A-140S blasting caps from the toolstring.
- Checked our entire inventory for other recalled caps.
- Arranged a return with the vendor as per recall procedures.
This was a close call, but because we followed a disciplined pre-job verification process, we caught the issue before it became a serious problem.
Why the Recall Happened
The recall was issued because some A-140S caps manufactured between January and March 2014 had unreliable detonation characteristics.
- Some failed to fire properly, causing misfires.
- Others had unexpected detonation delays, which is a major safety risk.
- The cause? Manufacturing inconsistencies in the detonation train.
Had we ignored the lot numbers, we could have faced:
- A failed perforation sequence, requiring a costly fishing operation.
- An unintentional misfire, creating a hazardous downhole situation.
- Lost time and credibility with the client.
Lessons for Wireline Engineers
This experience reinforced several key takeaways:
- Always check blasting cap lot numbers.
- Keep track of recalls and safety bulletins—they exist for a reason.
- Never assume that new equipment is problem-free.
- Even brand-new blasting caps can have manufacturing defects.
- Follow strict pre-job verification procedures.
- A last-minute equipment check saved our job that day.
- Remove all unused or recalled detonators immediately.
- Recalled caps must be taken out of service and returned to the vendor.
Final Thoughts: Safety is Non-Negotiable
In wireline perforating, there’s no room for errors—especially when it comes to blasting caps and detonation systems.
That day, a simple habit of checking lot numbers prevented what could have been a serious operational failure.
So, to every wireline engineer, perforation specialist, and wireline service provider—never skip the small details. They’re the ones that matter most.