Commercial expandable screen completions continue to grow.

Terra Tek and a group of oil companies have pooled resources to accelerate the adoption of expandables and overcome the twin challenges of reliability and suitability. Key objectives are to characterize and address mechanical integrity issues related to expandable materials under simulated earth loading and flow conditions and to publish functional requirements. This will enable operators to readily make comparisons between differing technologies such as expandable screens, gravel packs and stand-alone screens. Operators in this initiative include BP, BHP, ConocoPhillips, ENI (Italy), ExxonMobil, Statoil (Norway), Saudi Aramco and Total (France). Service companies that are participating and have already established reliability levels are Baker Oil Tools, Halliburton, Schlumberger and Weatherford.

The idea is to help develop the following:

• Independent assessment of expandable completion/screen systems;

• Comparative testing of various systems;

• Broad range of test results with limited cost;

• Reduction in risk in real well applications.

Arnis Judzis, executive vice president at TerraTek, said, "Expandable completions, particularly expandable screen systems, are a rapidly growing area with hundreds of installations in a wide variety of applications and services. As demand increases and the range of products available broadens, operators are faced with choices as to which system is best suited to their need(s). With the technology being relatively new, no industry accepted testing protocols or performance standards are available. Therefore, individual operators rely on either supplier information or commission their own testing at their expense. Experience from the aerospace industry on reliability studies and the analysis of their effects have been used to identify failure modes for expandable systems during different phases of product life: design and manufacturing, field installation and during long-term production/injection."

Characterizing failure modes, their effects and identifying critical elements will help provide the industry with a basis for sound technology adoption. Operators have also supported the initiative due do its "installation assurance" objective. This is the desire to avoid train wrecks and reduce non-productive time as seen in the past. Operators and suppliers have drawn up functional requirements that cover specifications for given well types and allow comparisons of expandable systems.

In this way the suitability of expandables can be assessed according to well construction needs. Consequently, expandables can be picked based on the specification a particular application requires. For example, zonal isolation for water shutoff purposes or cladding to repair damaged casing require different burst/collapse ratings as compared with shoe-to-shoe casing.

The ability of expandable screens to control the production of sand is a key determining factor as to their competitiveness with existing technology. Here the research intends to demonstrate that expandable screen products can deliver equivalent or superior sand control performance when compared to "Best in Class" techniques such as frac packing and openhole gravel pack.

While the development of an integral caliper will improve the collection of data such as downhole wellbore dimensions. This will assist in understanding the integrity of the expansion process and its subsequent completion efficiency.

An inline tool integrated with the expansion string would provide compliancy assurance, identify installation problems and allow troubleshooting and remediation at the well site. Clearly, this type of tool has great potential in reducing unscheduled downtime.

Standardization is important for certain components which are defined by API/ISO. These are the so-called "level playing field" regulations. This helps both operators and suppliers as performance is improved.

The benefits that are expected to be delivered are:

• Reliable, high productivity sand control completions;

• High well performance;

• Effective sand control;

• Best-in-class installation efficiency for sand control completions;

• Faster sand screen installation with improved sand control ;

• Deliver sand control completions with enhanced functionality; and

• Provide ability for selective completion and zonal isolation.

Functional requirements and technical specifications are based on field experience, testing and product development. Field experience covers general field and well specific conditions and an overview of loading during installation and expansion. The testing addresses areas such as plugging related collapse, compliance and gap, geomechanical loading, erosion and metallurgy. Product development includes liner hangers, packers and the lessons learned from isolating sections in both cased and open hole.

Judzis said, "With the industry's significant focus on deepwater applications, it is critical that a "trial and error" method of introducing this new technology is avoided so the potential value can be realized."