Thursday, February 19, 2009

Rotary Steerable System (RSS)

What is a Rotary steerable system (RSS)?
It permits downhole directional control whilst continuously drilling in rotary mode. At present, three classes of rotary steerable system exist:

  • fully steerable systems, allowing down hole control of both inclination and azimuth;
  • semi steerable systems, providing down hole control of inclination only (adjustable stabilizers)
  • vertical drilling systems, that actively seek vertical
The aim of this document is to provide information on:
  • the experience to date of rotary steerable systems
  • available rotary steerable;
  • technical, cost and usage data; and
  • the perceived benefits and drawbacks of these systems
Advantages of RSS over conventional mud motor techniques
Firstly, due to the elimination of the need for slide drilling:
  • Improved ROP, reducing drilling time;
  • Improved hole cleaning / lower ECD;
  • Reduced torque and drag, giving greater reach for ERD wells;
  • Reduced axial stick / slip problems.
It is also believed that rotary steerable systems give:
  • Smoother well bore, requiring less reaming;
  • More controllable build rates;
  • Improved bit life.
Types of wells that may benefit from rotary steerable technology include:
  • ERD wells that are beyond current comfort zones;
  • Designer wells where sliding limits achievable targets;
  • Deep, hot, directional wells where motors have problems;
  • High build rate, small diameter re-entry work;
  • Wells where slide drilling causes high ECD's / well bore stability problems;
  • Vertical wells where directional control is difficult;
  • Deep wells to reduce torque and drag generated at surface


Anonymous said...

haha...nice info...