A rotary steerable system (RSS) is a form of drilling

technology Technology is the application of knowledge to reach practical goals in a specifiable and reproducible way. The word ''technology'' may also mean the product of such an endeavor. The use of technology is widely prevalent in medicine, science, ...

used in

directional drilling Directional drilling (or slant drilling) is the practice of drilling non-vertical bores. It can be broken down into four main groups: oilfield directional drilling, utility installation directional drilling, directional boring (horizontal dire ...

. It employs the use of specialized downhole equipment to replace conventional directional tools such as

mud motor A mud motor (or drilling motor) is a progressive cavity positive displacement pump (PCPD) placed in the drill string to provide additional power to the bit while drilling. The PCPD pump uses drilling fluid (commonly referred to as drilling mud ...

s. They are generally programmed by the measurement while drilling (MWD) engineer or directional driller who transmits commands using surface equipment (typically using either pressure fluctuations in the mud column or variations in the drill string rotation) which the tool responds to, and gradually steers into the desired direction. In other words, a tool designed to drill directionally with continuous rotation from the surface, eliminating the need to "slide" a

. The first known patent application is from Christopher G. Cross in 1873 for "Drills for Boring Artesian Wells", followed in 1884 by the brothers Morris and Clarence Baker for a "Machine for Operating Drills"United States Patent and Trademark Office
/ref> The methods used to direct the well path fall into two broad categories, these being “push-the-

bit The bit is the most basic unit of information in computing and digital communications. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represente ...

” or “point-the-bit”. Push-the-bit tools use pads on the outside of the tool which press against the well bore thereby causing the bit to press on the opposite side causing a direction change. Point-the-bit technologies cause the direction of the bit to change relative to the rest of the tool by bending the main shaft running through it. The latter require some kind of non-rotating housing or reference housing in order to create this deflection within the shaft. The advantages of this technology are many for both main groups of users: geoscientists and drillers. Continuous rotation of the drill string allows for improved transportation of drilled cuttings to the surface resulting in better hydraulic performance, better weight transfer for the same reason allows a more complex bore to be drilled, and reduced well bore

tortuosity Tortuosity is widely used as a critical parameter to predict transport properties of porous media, such as rocks and soils. But unlike other standard microstructural properties, the concept of tortuosity is vague with multiple definitions and vari ...

due to utilizing a more steady steering model. The well geometry therefore is less aggressive and the wellbore (wall of the well) is smoother than those drilled with a motor. This last benefit concerns geoscientists, because better measurements of the properties of the formation can be obtained, and the drillers, because the well casing or production string can be more easily run to the bottom of the hole. Due to the relative high cost of this technology limited inroads to the lower end of the directional drilling marketplace have been achieved. As a result this sector of the marketplace is still dominated to a large extent by traditional motor steerable BHA technology. A number of entrepreneurs have made attempts to develop tools aimed at this market (Rotary Steerable Tools BVI, Terravici and Kinetic Upstream Technologies for example) however the impact made has thus far been limited.

References

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External links

HALO
from Scientific Drilling Internationa
(Website)RSS
from

Gyrodata Gyrodata, Incorporated is a privately owned company headquartered in Houston, Texas. The company has principal offices in Aberdeen, Scotland and Kuala Lumpur, Malaysia. Gyrodata is a leading provider of technology and services, including gyroscop ...

br>(Website)
from TerraVici Drilling Solutionsbr>(Website)

Well-Guide RSS
from

Website

Rotary Steerable System
from APS Technology
Website

Rotary Steerable Motor
from APS Technology
Website

PowerDrive
from

Schlumberger Schlumberger Limited (), doing business as SLB, is an oilfield services company. Schlumberger has four principal executive offices located in Paris, Houston, London, and The Hague. Schlumberger is the world's largest offshore drilling compa ...

Website

AutoTrak
from

Baker Hughes INTEQ Baker Hughes Company, organized in Delaware and headquartered in Houston, is one of the world's largest oil field services companies. The company provides products and services for oil well drilling, formation evaluation, completion, productio ...

Website

Geo-Pilot
an
EZ-Pilot
from Sperry Drilling Services
Website

Pathmaker
from

Pathfinder Pathfinder may refer to: Businesses * Pathfinder Energy Services, a division of Smith International * Pathfinder Press, a publisher of socialist literature Computing and information science * Path Finder, a Macintosh file browser * Pathfinder ( ...

Website

Revolution
from Weatherford
Website

DeviDrill
from Devico AS
Website

D-Tech Rotary Steerable
from D-Tech Drilling
Website
Drilling technology

See also

References

External links