Conveying OH pressure and sampling toolstring

JANG14471 Conveying OH pressure - Well Intervention - Welltec x
  • Well type Horizontal exploration well
  • Max. deviation 89.64°
  • Max. temperature 142°F (61°C)
  • Max. pressure 4,764 psi


In Angola, the Well Tractor® added more applications to its repertoire when it conveyed a third party pressures and sampling toolstring in a horizontal well. It was very critical for the operator to take pressure measurements and fluid samples from this particular formation just below the 9 5/8” casing shoe.

They chose to convey the toolstring using a Well Tractor to save two days of rig time and the associated cost of using the alternative pipe conveyed system. Using spacers ensured that the Well Tractor would be inside the 9 5/8” casing shoe when located at the required measurement depth. This would prevent the tractor wheels cutting into and potentially getting stuck in the formation.


A System Integration Test (SIT) was carried out with two purposes: to ensure the compatibility of the Well Tractor with the third party tools and to confirm that the Well Tractor could push the toolstring.

Both objectives were achieved. Welltec® also came up with an ingenious plan for fishing the toolstring in the case it would get stuck. A 3 5/8” tool adapter was installed at the top of the toolstring, just below the Welltec Release Device® (WRD). This would enable fishing of the entire toolstring by using the available fishing kit, which was suitable for the 3 5/8” tool OD only.

The toolstring was configured with two multi-sampler modules, two fluid analyzers, a dual pump out module for sample clean-out, a 1 gallon sample chamber and two powered caliper tools. It was conveyed by a Well Tractor 318 to collect the planned pressure measurements and samples from just outside the casing.


The operation was so successful that the operator immediately scheduled Welltec for the next similar operation.

Excellent pre-job planning, support and execution by Welltec’s team in Angola were contributing factors to the success, which opens up more opportunities for Welltec globally.