E-Line production tubing and SSSV clean-out saves one week

Challenge
Downhole access
JMX143218 E-Line production tubing and SSSV clean out - Well Intervention - Welltec
  • Well type Producer
  • Max. deviation 20.5°
  • Max. temperature 277°F at 12,260 ft (136°C at 3,737 m)

Background

Careful planning combined with experience were the decisive factors behind this successful Intervention, when an offshore Mexico operator needed to set a pressure and temperature sensor in two wells.

To be able to collect the accurate data, the client had to install a downhole pressure sensor in each well with slickline. In one of these wells the Subsurface Safety Valve (SSSV) was not hermetic and the production tubing had a restriction, which prevented slickline from reaching setting depth with the pressure sensor.

Production tubing clean-out is typically a Coiled Tubing (CT) operation, but for this operation CT would take at least a week for deployment due to the lack of fluid and stimulation vessels. Welltec’s lightweight clean-out solution therefore represented a much faster alternative. The strategy was therefore to perform both a production tubing clean-out and SSSV clean-out
with the same e-line robotic tools.

Operation

Before the operation the tools were thoroughly prepared and tested at the well site, and a gauge run was performed to confirm exact location of the restriction. Welltec® mobilized a wide range of tools and accessories to offer the client a variety of solutions on site. First the Well Miller® cleaned from surface through 8,520 ft (2,660 m). Two scale bridges were encountered and efficiently removed from 174 to 335 ft and from 531 to 538 ft (53-102/162–164 m). After the successful production tubing operation, the Well Cleaner® Wishbone Honer (WBH) was run in hole to clean the SSSV.

Because the valve was not sealing properly, the hydraulic pressure was reduced from 2,700 psi and 1,000 psi to 1,900 psi and 900 psi, which enabled the SSSV to open and close more easily. The successful operation enabled the operator to set a downhole pressure sensor with a 2.5″ outer diameter, which in conjunction with the two wells, will help to measure pressure and perform a reservoir analysis.

Achievements

Welltec met both objectives with one mobilization and dramatically reduced the duration of the operation, performing both interventions in 72 hours – including rig up and rig down. Using CT would have added at least one week to the operation as well as more personnel.

Welltec’s e-line solution eliminated the need to mobilize a stimulation vessel, fluids like acid, diesel and solvents, as well as the CT unit itself.

Furthermore, Welltec’s e-line tools increased the flow area by 50% thanks to the 3.5” bit used with the Well Miller versus what would have been a 2.625” bit for the CT program. The operator had previously used the WBH with great results and as left certain of the capabilities that Welltec’s solutions bring for scale removal.

Welltec met both objectives with one mobilization and dramatically reduced the duration of the operation, performing both interventions in 72 hours – including rig up and rig down.