There’s a kind of silence that hits after a near-miss. Not the loud kind that follows a gunfire or a tool drop—but the kind that creeps in when you realize how close you were to losing control.

That’s what we faced the day we had an unintentional pull off (UPO) at surface. A simple lift, a minor snag, and a few seconds of tension buildup nearly sent the gunstring crashing down with full force. No injuries, no lost tools—but a serious reminder of how wireline logging operations can change in the blink of an eye.

This job rewrote how we handle surface retrieval in tight locations. And the changes we made after that day now shape every wireline and perforating run we do—especially in the modern high-speed, high-stakes world of cased hole wireline.

The Job: Routine Perforation, Tight Space, Bad Angle

We were working in a congested pad environment. The well was prepped for a perforation stage, the wireline truck in place, pressure control equipment stacked and pressure-tested. Everything looked good on paper.

The issue came when lifting the gunstring back into the lubricator. The setting sleeve caught on the bottom union of the blowout preventer (BOP)—something that happens occasionally. But what made this different was the tight cable slack. Because of the tight location, we didn’t have much room to give.

And because of that, there was no reaction time.

In just over three seconds, the tension spike went from safe to over limit. The weakpoint popped. The plug drove down into containment. We were lucky—the lubricator was still low enough to trap the falling toolstring. It didn’t fall over. It didn’t strike equipment. And no one was standing under it. But it could’ve gone very differently.

Understanding What Went Wrong

This wasn’t a wireline equipment failure. The logging cable held. The winch system performed as expected. The failure was procedural. We didn’t have:

• A clear line of sight to the entry point

• Proper slack in the line

• Controlled winch speed during pick-up

• A line entry guide to reduce snag risk

Three seconds. That’s all it took. And in those three seconds, we were completely reactive.

Implementing a Safer Retrieval SOP

After the incident, we rewrote the way we handle gunstring retrieval. This isn’t just about surface operations—it’s about applying complete wireline solutions from wellhead to winch.

Here’s how we do it now:

Wireline Gunstring Pull-In Procedure

1. Line Entry Guide Is Mandatory
No matter how experienced the crew is or how open the location looks, we install a line entry guide at the bottom of the lubricator. This guide helps prevent the setting sleeve or other downhole tools from snagging.

2. Visual Contact at All Times
The engineer or line operator must maintain a clear line of sight to the tool entering the lubricator. No pulling blind. If the sightline is obstructed, we pause and reposition.

3. Manual Slack and Winch Control
Two people minimum at the line during pull-in. One operates the winch at a safe speed—especially at OD transitions. The second applies manual guidance and tension, “sucking in” the toolstring by hand when needed.

4. Adjust Slack for Tight Locations
If location constraints reduce cable slack, we manually reposition the wireline truck or reevaluate line length. No lift is attempted without adequate slack for emergency reversal.

5. No Personnel Under the Stack
As always, the zone beneath the lubricator remains clear. If the gun falls, it doesn’t fall on someone.

6. Over-Tension Alarms Are Pre-Set
Winch systems must have active alarms set within normal operating tension. This gives the crew those crucial 3 seconds to stop the system if tension rises unexpectedly.

Why This Matters in Cased Hole Logging Operations

The cased hole logging service market is defined by speed and safety. In wireline services oil and gas, pulling fast without process might win a few minutes—but when it fails, it can cost hours or worse.

Surface UPOs threaten:

• Well integrity

• Crew safety

• Perforating gun condition

• Confidence in wireline providers

• Scheduling across an entire pad

This isn’t just about risk—it’s about reliability. And that’s what clients are paying for.

How This Is Taught in Wireline Courses

This incident became a featured module in our wireline courses, especially in wireline oilfield safety training and wireline tech fundamentals.

Trainees now learn:

• How to read tension curves during pull-ins

• What “tight locations” really mean in winch control

• How to manually guide a wireline unit back into the lube

• The role of weakpoints in protecting the string

• How to build “reaction windows” into high-risk moves

We even simulate UPO tension spikes using pre-recorded logs so that new hands learn what a three-second spike feels like—before they experience it for real.

Supporting Safer Wireline Business Operations

Whether you’re managing a team, owning a wireline company, or building out a fleet of wireline trucks, these are the lessons that prevent downtime and build trust. This protocol now applies to:

• Perforation services in plug and perf operations

• Wireline well logging with long-toolstring assemblies

• Cement bond log (CBL log) retrievals after flowback

• Downhole camera deployments in well integrity work

• Fishing wire line pre-runs to retrieve stuck tools

It’s also baked into our daily job prep briefings. Because reminders don’t work unless they’re repeated.

Final Thoughts – Safety Starts at the Surface

We often focus on what happens downhole—wireline control systems, perforating systems, and pressure integrity. But some of the biggest risks in oil field wireline happen five feet off the ground.

This job reminded us that it’s not just about tools—it’s about timing, teamwork, and seeing what’s happening at the wellhead in real time.