Well Control - Blow Outs

Question 0

If maintaining mud weight greater than pore pressure is fundamental to well control why not just always use heavy mud?

Answer 0

If mud is too heavy it will fracture the rock and therefore risk the well caving in, not producing etc.

Question 1

What is the fundamental rule of well control?

Answer 1

Maintaining a mud weight greater than the rock pore pressure

Question 2

How do you evaluate formation strength and therefore maximum mud weight?

Answer 2

to evaluate the maximum mud weight you determine the strength of the rock using a leak off test where you pressure the well until the point where each incremental increase in volume pumped results in a pressure increase less than the volume pumped… Indicating rock is cracking and mud leaking off.

Question 3

What is the primary method of primary well control?

Answer 3

Hydrostatic head of the mud / brine column

Question 4

What are the three types of secondary well control?

Answer 4

1. BOP
2. Casing
3. Open hole formation strength

Question 5

Three types of tertiary well control

Answer 5

1. Bayrite / cement plugs
2. Dynamic kill
3. Running shoes :-)

Question 6

What is a pit drill?

Answer 6

Drilling supervisor lifts the float in the mud pit. Rising mud indicates there’s more fluid coming out of the system then going in… Indicating a kick. It is then measured to see how long it takes the team to notice this and react by stopping drilling, potentially shutting in the the well.