I still remember the day like it was yesterday. We had just rolled out to a job site for a cased hole logging operation. Everything seemed routine—weather was clear, tools were loaded, and the wireline truck was freshly serviced. But what I thought would be a standard day in the oilfield turned into one of those defining moments that remind you why best practices aren’t just suggestions—they’re lifelines.
The Ram That Wouldn’t Close
First hiccup? The blowout preventer (BOP) rams wouldn’t fully close. In the middle of rig-up, the wireline control system flagged abnormal pressure, and the rams were stuck halfway. Turns out, hydraulic leakage from dirty hose ends had compromised the seal. Dirt had worked its way into the hydraulics during connection at the accumulator. No full closure meant potential toolstring hang-ups and a compromised seal around the logging cable—something no wireline engineer wants to gamble with.
That was a near miss. Lesson learned: never allow hose ends to touch the ground. Now, every wireline unit I work with gets hose ends cleaned and capped before connection. It’s a small thing that makes a huge difference in well integrity and overall wireline safety.
Grounding Failures and Ghost Shorts
The next hit came during a perforation well prep job. The switch test on our wireline perforating string kept failing. Intermittent shorts, impossible to trace to one gun or one switch. Eventually, I pulled the gunstring apart and found it—damaged insulation on a through wire caused by poor loading technique. The tubing had bunched, stripped back insulation, and created a short to mass.
Now, every time I build a perforating system, I tape the primacord to each charge and wrap the tubing candy-cane style—tight, consistent, and secure. We also implemented grounding springs in every sub. It’s become a standard in our wireline and perforating process and has eliminated those mystery misruns that haunted us.
Measuring Head Madness
You’d think that would be enough for one month, but then the depth system failed mid-job. Measuring wheel calibration was off. Warrior showed a different depth than the winch panel. Tension readings were inconsistent. That one hurt—set us back four hours and cost us client trust.
Now? Before any wireline truck leaves the yard, we spin the wheel, check for the 2.023 ft/rev calibration, verify tension deflection, and confirm bearing stability. Any hint of looseness, and we replace it. No job leaves unless the Warrior, winch panel, and backup are all in sync. It’s made a massive difference in wireline logging accuracy and reduced post-job corrections.
Weight Bar Woes
And let’s not forget the weight bar rebuild that nearly turned into a disaster. Wrong sub assembly—pin and box mismatched. One was Acme, the other GO. That error nearly cost us the ability to run a cased hole wireline tool. Since then, every job begins with a full teardown of weight bars, CCLs, and connections if the crew didn’t rebuild it themselves. We verify redress kits, inspect the electrical, and rebuild from the ground up. It’s a non-negotiable part of our preparation, especially in cased hole well services where tool reliability is everything.
These experiences taught me the value of meticulous preparation. Wireline well logging is unforgiving. You’re dealing with delicate electronics, high-pressure zones, unpredictable downhole environments, and strict schedules. Whether it’s running pipe caliper tools for caliper logs or preparing a pump down perforating system with wireline perforating guns, one small oversight can cause an entire job to collapse.
If you’re new to this field or looking to level up your skills, I can’t emphasize enough the importance of understanding these basics. That’s why I’ve put together a series of wireline courses covering these very scenarios—real-world lessons, best practices, and complete wireline solutions from measuring head maintenance to wireline tools assembly. These courses aren’t theory—they’re survival guides.
Visit my wireline course page to get started.
Wireline isn’t just a job—it’s a craft. Treat it that way, and you’ll go far.