Wireline Operations
Wireline Operations tests well control for slickline, electric line, and braided line. The exam expects correct lubricator sizing, BOP and grease-injection practice, and recognition that the wire is not a barrier.
Core rules
- The lubricator must be pressure-rated for the maximum expected surface pressure and long enough to contain the complete toolstring plus a safe allowance.
- The wireline BOP stack usually provides pipe rams, shear/seal rams, and a grease-injection head or stuffing box. Test before running in.
- For braided or electric line, grease injection maintains a seal around the moving wire; monitor injection pressure and return flow.
- The well must be shut in and pressure equalized before the lubricator is opened.
- Depth control depends on measured toolstring length and wire depth; do not rely on guesswork.
Worked example
A toolstring measures 8.4 m. The available lubricator is 7.5 m from the wireline BOP to the top connection. It cannot be used. The minimum lubricator length should be at least toolstring length plus about 0.5 m for the rope socket and clearance, so a 9 m lubricator is required. If a longer lubricator is unavailable, break the toolstring into a shorter assembly or use a different deployment method; do not run with the toolstring protruding into the stuffing box.
Traps
- Running a toolstring longer than the lubricator.
- Opening the well before equalizing.
- Losing grease injection and continuing to move wire.
- Assuming the wire itself seals the well.
- Shearing wire without confirming the shear ram and wire size.