Development of operation and mainteance procedures for zonal isolation tools

Abstract

Stimulation operations of unconventional formations, such as tight oil- and shale gas formations are often necessary to achieve profitable hydrocarbon production. Several stimulation techniques and equipment are used for different applications, including hydraulic fracturing and acid stimulation. The oil and gas industry continuously develop new and more efficient techniques and equipment to save time and costs related to production of hydrocarbons. According to the U.S. Energy Information Administration, 47 percent of the world’s gas reserves and 11 percent of the world oil reserves can be found in unconventional shale formations (U.S. EIA, 2013). Therefore, the potential of entering the market with innovative and efficient technology for stimulation operations is promising.

The content of this thesis is based on a zonal isolation tool used for stimulation of unconventional oil- and gas wells. The zonal isolation tool is a re-design of a previously developed prototype of an all-electric annular fracture tool developed by Target Intervention. The background theory of well stimulation operations as well as reviews of existing technologies including the current zonal isolation tool is presented in the thesis.

The main advantage of the zonal isolation tool developed by Target Intervention is that it is electrically operated with coiled tubing. Well stimulation tools used in the industry today are usually mechanically operated, thus limiting the control of the operation process. Thus, the goal is to reduce the operation time by being able to locate perforated zones in the reservoir formation more effectively by the use of integrated real-time electrical monitoring systems.

Operation and maintenance of the Zonal Isolation Tool are two of the most critical aspects related to asset management. After the tool has been manufactured, tested and approved ready for operation, efficiency, reliability and maintenance management are important topics the company needs to consider in relation to operation and maintenance. The main objective with this master thesis is related to development of procedures for operation and maintenance of the Zonal Isolation Tool. Critical aspects of development and design of procedures are discussed, as well as background theory of maintenance and maintenance management.