PLT logging while tractoring with Well Tractor® 212 Tandem

JANG14471 Conveying OH pressure - Well Intervention - Welltec x
  • Well type Oil producer
  • Max. temperature 176°F
  • Bottom-hole pressure 2,176 psi
  • Well head pressure 1,885 psi


An operator required Production Logging (PLT) data from a well with a long lateral of more than 16,000 ft (TD 20,161 ft). Because of the length of the lateral and the forces required, the only way to reach TD was to use the Well Tractor 212 in tandem configuration. The PLT data needed to be recorded in both down and up passes in real time while also powering the tractors, a process known as Logging While Tractoring (LWT).

As is the case with many horizontals, the operator expected debris in the well, so clean-out services were necessary prior to the PLT operation.


The objectives of this intervention consisted of two tasks:

- Perform clean-out/drift runs with Well Tractor 212 in tandem configuration and the Well Cleaner® Power Suction Tool (PST). Additionally, the Welltec® Reverse Circulating Bit (RCB) would be used as a contingency option.
- Perform PLT using the tractors for LWT on a mono cable

Welltec carried out significant planning prior to the operation, including well simulations and physical testing. Well parameters, such as wireline tension, pick up weight, and tractor pull forces were confirmed to be within acceptable limits to handle the 16,000-foot horizontal section. Simulations demonstrated that the pull force needed to reach TD could only be achieved with two Well Tractor 212s’ in a tandem configuration. Prior to mobilization, tractors were tested in-country to ensure the tools met the necessary conditions to carry out work on the project.

First, the PST was run with the Well Tractor 212 in tandem configuration to remove debris in order to reach TD and remove potential contamination to the PLT data. It took three clean-out runs with the PST before there was a clean path to TD. Subsequently and over the course of three runs, the Well Tractor conveyed the PLT through the lateral to TD, capturing logging data in LWT mode.


Welltec achieved the client’s objectives with flawless execution, using Well Tractor 212 in tandem configuration: three runs for clean-out services to reach TD, and three PLT LWT runs to capture data. In total, across all runs, the tractors conveyed the toolstrings 146,400 ft. The longest accumulated distance tractored during one run was 37,400 ft over several passes.

The logging program was executed fully, marking the first time LWT has been performed with Well Tractor 212 in tandem configuration. Data were successfully acquired in both down and up passes, providing the client with essential knowledge of the reservoir and the well’s production profile.

Welltec is the first company able to provide technology and solution that allowed the client to reach TD of 20,161 ft (6,145m) and acquire PLT data in this well.