Smart Drilling Systems allow drillers knowledge of what is happening at the bottom of the hole while drilling

"Smart" drilling systems are capable of sensing and adapting to conditions throughout the drilling operation and around and ahead of the drill bit. These systems operate in real time; that is, they analyze and react to data collected during drilling and are designed to modify the trajectory, speed, and operation of the bit when parameters measured by the sensors dictate. They may be self-guided or directed from the surface with minimal operator intervention.

Smart drilling systems must be able to:

• sense the properties of the rock at and just ahead of the bit,

• sense the condition of the bit and other critical drilling system components,

• collect the data in a form that can be easily and quickly transmitted to the surface,

• use these data to adjust drilling rate and/or trajectory to changing conditions, and

• perform these functions under extreme conditions.

Sensing the properties of the rock through which the drillbit is cutting is important because rock properties affect the rate of penetration (ROP) and bit wear. A smart system must be able to accurately measure parameters such as formation porosity, pore pressure, temperature, mineralogy, rock strength and stress state. These parameters provide estimates of the formation's elastic properties (brittleness, ductility, hardness) and energy dissipation rate (wave attenuation). As rock properties change with depth, a smart drilling system adjusts drilling parameters (e.g. weight on the drill bit and rotary speed, torque, pump rate) to reduce stress on the bit and prevent problems (e.g. blowout, loss of circulation, or drilling off-course).

The sensors that monitor the bit and other elements of the drilling system allow the smart drilling system to anticipate problems and either make adjustments or take preventative action to avert mechanical problems. These sensors must monitor wear rates, mechanical stresses, pressures, temperatures, and flow rates. Drill bit sensors must also be able to monitor the position of the bit in three-dimensional space, in order to steer the bit to the target. In combination with the data on rock properties, this data will be employed by the smart system to determine the optimal rate at which the drill can effectively penetrate subsurface formations with a minimum of damage and wear.

Telemetry methods used to transfer information collected by downhole sensors must be capable of data transfer rates be on the order of kilobits per second or higher in order to be useful. This data must be processed with robust and flexible software that can accurately assess conditions and properly adjust the drilling parameters. Subsurface components of this system must be capable of operation in extreme conditions: temperatures that can exceed 350 degrees Fahrenheit (175 degrees Celsius) and pressures greater than 10,000 psia.

Most drilling systems today have a limited ability to analyze the rock or condition of the bit downhole. Although advances have been made in directional drilling technology, guidance systems for drilling deep reservoirs are still relatively primitive. Measurement-while-drilling (MWD - measurements taken while drilling the well with tools which are an integral part of the drill string) technology exists but is expensive, and relatively slow. Pre-Deep Trek NETL-funded research has made significant progress in developing cost-effective, high temperature logging-while-drilling systems, but the electronics and seals of these systems are still limited to temperatures less than 350 degrees F. Because of these limitations, the drilling process must be interrupted to obtain down-hole information.

Currently, there are three Deep Trek projects focused on the development of improved technologies and components for smart drilling systems.

High Temperature Electronic Components JIP
Honeywell International, of Plymouth, Minnesota, is developing a suite of high temperature electronic components that can be used for instrumentation in deep gas drilling systems. Honeywell will conduct the project through its Solid State Electronics Center for Excellence, and will form a Joint Industry Participation (JIP) group to develop system specifications prior to product development. Potential partners in this group include Schlumberger Technology Corporation, Diamond Research, Micropac Industries, and E-Spectrum, as well as other petroleum industry service companies and operators. Total project cost will be $8.6 million, of which $2.6 million will be a cost share contribution by the industry partners.

High Temperature/High Pressure MWD Tool Development (DE-PS26-03NT41835)
Schlumberger Technology Corporation of Houston, Texas, will design and commercialize a high-temperature (approaching 400 degrees F), high-pressure, measurement-while-drilling tool that will be able to provide direction, inclination, toolface and gamma ray measurements continuously in real time. The tool will be fully retrievable while the drillstring is downhole, eliminating the need to remove the entire drillstring assembly to retrieve the MWD equipment. If successful, development of this capability will improve the economics for deep well drilling by reducing down time - boosting the overall rate of penetration in deep hostile environments. Total project cost is $5,888,159, with a cost share contribution of $2,074,488 from the industry partners.

Electromagnetic Telemetry Tool for Deep Well Drilling Applications (DE-FC26-02NT41656)
E-Spectrum Technologies of San Antonio, Texas, is developing a wireless, electro-magnetic (EM) telemetry communications system that will transmit data to and from downhole equipment in real time, enabling both surface processing of downhole sensor data and direct surface control of downhole tools. E-Spectrum will build and field-test a prototype of the system for use at depths of at least 20,000 feet and temperatures up to 392° F (200° C). The system will be composed of a surface unit receiver/transmitter, downhole data-acquisition module, downhole repeater module, and a downhole receiver/transmitter module. The downhole components will be designed as stand-alone modules, using ruggedized mechanical packaging that will fit inside 1.25-inch O.D. pressure enclosures built within the drillstring. The project, slated to run in three phases and be completed by August 2005, will cost a total of $861,000, of which $177,000 will be a cost-share contribution from E-Spectrum.