WAB - Welltec Annular Barrier 1920 X 1080 (2)
WAB - Welltec Annular Barrier 1920 X 1080 (2)

Zonal isolation

Cementless, extended reach reservoirs

Zonal isolation

  • Applications
    High performance, rotatable, zonal isolation.
Segmented well design increases options to mitigate reservoir uncertainty and maximizes the economic value of wells.

Geological uncertainty

Geological uncertainty is often a critical risk factor as it defines the outcome and return on a field development over the life of well.  

Extensive efforts and resource is invested to understand and describe the geology and capture/quantify the uncertainties.

As the field matures, increased data captured, improves the models, impacting development decisions. However, the economic value of the project remains dependent on the ability to mitigate the risks associated with remaining uncertainties.

For example, uncertainty associated with the distribution of high permeability streaks in the oil reservoir deliver risk associated with water or gas breakthrough, declining oil production and reduced sweep efficiency impacting total reserves and the project cash flow. 

Integration of key uncertainties in well planning often ensure good prediction of the reserves and the probability of success, however the choice of well technology and completion design will control the method optimize and act to mitigate the risks long-term.

Extended reach horizontal reservoir

Also to increase net present value of their assets, extended reach horizontal reservoir sections are becoming critical to operators looking to increase well productivity and maximize their ROI. Extended reach lower completion design creates significant concerns over the ability to execute a conventional cement or perforated liner well design due to the high inclination nature of the reservoir section.

To achieve this it is critical to design the well with reliable isolation between lower completion and open hole without the need for cement.

Our ISO 14310 rated, metal expandable WAB® (Welltec® Annular Barrier) for open hole zonal isolation, facilitates the ability to deploy ‘cementless’ extended reach, multi zone, horizontal, lower completions. The WAB provides the on-demand, high pressure zonal isolation across varying borehole geometries unaffected by thermal changes in the wellbore, so often a problem in conventional open hole isolation.  

The WAB for Zonal Isolation between the lower completion and the open hole enables the compartmentalization of the reservoir into many, discrete sections. Whether an injector or producer, this gives the operator the best options to mitigating reservoir uncertainties and maximize the value of the well.

Case highlight

Two WABs installed to isolate shallow reservoir for future production. Four WABs installed in lateral for zonal isolation between reservoir zones...

Read case

Modelling services

Successful Welltec® Annular Barrier (WAB®) sealing across the cap rock can be ensured through 3D geomechanical modelling of the expansion of the Welltec packers into the rock formation.

In specific projects flow modelling is also used in the packer configuration to ensure the zonal isolation benefits and minimize risk of flow through formation behind the packers.

Read more

Products and services