Annular Velocity (AV)
Annular Velocity (AV) is how fast of fluid in annulus while pumping. Three main factors affecting annular velocity are size of hole (bigger ID), size of drill pipe (smaller OD) and…
Deviated Hole
What does Deviated Hole mean? A deviated hole is a wellbore that is inclined and it's not in a vertical direction. Ideally, a deviated hole is drilled on purpose in a horizontal…
Hole Cleaning
Hole cleaning can be a real problem when drilling deviated wells. It has been proved that for wellbores with an inclination angle greater than 30°, the removal of cuttings beds…
Equivalent Circulating Density (ECD)
Equivalent Circulating Density (ECD) is the effective density that combines current mud density and annular pressure drop. ECD is vital for drilling engineering since it limits how depth of each section…
Slow Circulation Rate (SCR)
Slow Circulation Rate is a circulation rate which will be used in well kill operation. Typically, slow circulation rate pressure (SCR) is recorded from each particular flow rate and the pressure…
Jet Optimization and Planning
For many years, engineers have known that hydraulics play an Important role in cleaning the face of the formation so that a bit can drill faster. This first became evident…
Hydraulic Rotary Drilling
Oil well drilling utilizes tri-cone roller, carbide embedded, fixed-cutter diamond, or diamond-impregnated drill bits to wear away at the cutting face. This is preferred because there is no need to return…
Types of Fluids
In geotechnical engineering, drilling fluid is used to aid the drilling of boreholes into the earth. Often used while drilling oil and natural gas wells and on exploration drilling rigs, drilling fluids are also used for much simpler boreholes,…
Drilling hydraulics
The material in this section provides a straightforward explanation of what is covered by the broad term “hydraulics” along with a description of basic hydraulic principles utilized in drilling. The…
Drilling fluid types
There are several different types of drilling fluids, based on both their composition and use. The three key factors that drive decisions about the type of drilling fluid selected for…
