Objectives and problems to be solved:
The larger hydrocarbon reservoirs in Europe are rapidly depleting. The remaining marginal fields can only be exploited commercially by the implementation of new 'intelligent' technology, such as electric Coiled Tubing drilling or Intelligent Well Completions. Steel CT with an internal electric wire line is the current standard for such operations. Steel CT suffers from corrosion and fatigue problems, which dramatically restrict the operational life. The horizontal reach of steel CT is limited due to its heavy weight. The inserted wire line results in major hydraulic power losses and is cumbersome to install. This project aims to solve these problems by researching and developing a high-temperature, corrosion and fatigue resistant thermoplastic Power & Data Transmission Composite Coiled Tubing (PDT-COIL) for electric drilling applications. This PDT-COIL contains embedded electrical power and data conductors and a fibre-optic sensing and monitoring system. Compared to conventional rotary drilling, such a PDT-COIL will result in 45% less required workspace, 50% reduction of rig height, 60% noise reduction, 70% less rock cuttings and a power exhaust generation reduction of 85%. The PDT-COIL will result in 35% overall cost savings on the exploration of hydrocarbons. Time to first oil will be reduced due to the support of enhanced logging while drilling capabilities.
Description of the work:
The project consists of two main phases.
In phase A, research will be conducted on all components of the Intelligent PDT Coil.
In phase B, these components will be combined into a test model. This scale model will be mounted at the end of a steel coiled tubing and field-tested. The objectives of this test are to prove the feasibility of electric drilling with a PDT-COIL and the continuous monitoring of both the drilling process and the structural integrity of a coil. Upon completion of phase A, the project will be evaluated. If the results of phase A are encouraging, a renewed project proposal will be submitted to the European Commission for the funding of phase B. This renewed project proposal may be submitted while phase A is still ongoing, to assure continuity in the project.
Expected results and exploitation plans:
The structural composite layers of the CCT form the main component, these will have to carry all the mechanical, thermal and chemical loads. They consist of both carbon and glass fibres embedded in high performance thermoplastic polymers. The electric conductors (which are embedded in the wall thickness) provide electric power for Electric Submersible Pumps or Electric Drilling Motors and can also be used for data transmission. They consist of copper wires and are insulated by the structural glass layers. A fibre-optic Sensing and Monitoring System will be embedded in the wall along the entire string length. This system measures on-line relevant parameters, monitors the structural integrity of the PDT-COIL and can be used for data transmission. The composite material is virtually insensitive to fatigue, so the limiting factor for the service life will be the wear characteristics of the coating and chemical ageing of the polymer matrix material. Of these the chemical ageing is most important because a coating can be reapplied to the coil if necessary. Therefore monitoring of the chemical ageing of the coil is an important factor for efficient application. For the operation of the PDT-COIL, a new control system will be necessary. Existing CT software will be modified to account for the behaviour of the composite material and the electrical equipment. The sensing and monitoring system will be integrated in the control system. Existing surface equipment needs to be modified for optimal performance of the PDT-COIL. These modifications will be designed and tested. The PDT-COIL will be designed for existing Electric Drilling Motors and existing Bottom Hole Assemblies, so no modifications are required for the downhole equipment.
Funding SchemeCSC - Cost-sharing contracts
2260 BB Leidschendam
7825 VJ Emmen