Drilling and Production Flashcards

What is the primary purpose of a blowout preventer (BOP) stack in drilling operations?

Answer: To seal the wellbore and control well pressure

A BOP stack is designed to seal the wellbore and prevent uncontrolled release of formation fluids during drilling.

In directional drilling, what does the term 'dogleg severity' refer to?

Answer: The rate of change in wellbore angle and direction per 100 feet

Dogleg severity measures the rate of change in wellbore inclination and azimuth, typically expressed in degrees per 100 feet.

What is the function of a 'mud motor' (downhole motor) in drilling?

Answer: To convert hydraulic energy of drilling fluid into rotational energy to turn the bit

A mud motor uses the hydraulic power of circulating drilling fluid to rotate the drill bit independently of the drill string rotation.

Which type of casing is set first when drilling an oil or gas well?

Answer: Conductor casing

Conductor casing is the first and shallowest casing set to prevent shallow formation collapse and direct returns to the surface.

What does 'WOB' stand for in drilling engineering?

Answer: Weight on Bit

WOB (Weight on Bit) is the amount of downward force applied to the drill bit to facilitate penetration of the formation.

In production operations, what is the purpose of a 'choke' on a wellhead?

Answer: To control flow rate and pressure from the producing well

A choke is a flow restriction device used to control production rate and regulate wellhead pressure.

What is 'equivalent circulating density' (ECD) in drilling?

Answer: The effective mud weight at a given depth accounting for annular pressure losses during circulation

ECD represents the total equivalent mud weight felt at the bottom of the hole, including both static mud weight and friction pressure from circulation.