It was a hot, dusty afternoon out in the field. We were on a multi-run cased hole wireline job, prepping for a perforation well with full wireline pressure control equipment. The crew was sharp, the wireline truck had just finished rig-up, and the logging cable was perfectly aligned through the grease head and BOP.
But something didn’t feel right.
The equipment stack looked good—freshly cleaned and assembled—but I hadn’t seen any documentation on a recent pressure test. So I called a pause. Some rolled their eyes. “We test these in the yard,” someone said. “It passed 1.5 times the working pressure.”
That’s great—for the shop.
But on location, where the well’s real, the pressure’s live, and people’s lives are on the line, you test again. Every time.
Why We Test on Location
In wireline services oil and gas, it’s standard practice to test pressure control gear—lubricators, grease heads, pump-in subs, wireline BOPs—before opening the well. We’re dealing with dynamic wells, unpredictable formations, and sometimes questionable wellhead pressure data. That’s why I always say:
Don’t trust it until you test it. On location. With your crew watching.
We filled the lubricator, applied the correct grease pressure, and began the pressure test—but carefully, never exceeding the working pressure of the lowest-rated component. That’s a golden rule in the wireline business, especially with customers on site and full strings of perforating guns downhole.
The entire wellhead assembly held pressure steady. No leaks. No failures. I signed it off. Only then did we continue with operations.
Controlled vs Field Testing
Back at the yard, yes—we certify gear at 1.5x its working pressure. That’s test pressure, done in a controlled environment with proper setup and no non-essential personnel nearby. But that’s not the same as on-location pressure testing.
In the field, we test up to the maximum working pressure—never beyond. It’s not just best practice. It’s about safety, performance, and being a reliable wireline service provider in an industry where reputations are made (or lost) in seconds.
What I Cover in My Wireline Courses
In every wireline tech course I run, I emphasize pressure testing for:
- Perforating services
- Pump down perforating jobs
- Production logging services
- Cased hole wireline and formation evaluation
- Plug and abandon operations
- High-pressure fishing wire line retrievals
No matter what you’re doing—caliper logs, cement bond logs, or running a downhole camera—your success hinges on whether your wireline control systems are pressure-tight before you break that seal on the well.
Final Field Advice
If you’re on a job with pressure control equipment, remember:
- Always test before you open the well
- Never exceed rated working pressure in the field
- Use proper grease seal during test
- Bleed off safely after the test is complete
- Trust your gut—if you’re unsure, test it again
This industry—whether it’s wireline perforating, pipe recovery, or standard wireline logging—demands discipline. That pressure test might seem like a delay now, but it could save your string, your job, or even your crew’s safety down the line.