Schlumberger Drilling Course CDs BOP Blowout Prevention Equipment

Summary

This video provides an in-depth explanation of blowout prevention in drilling operations. It covers the process of managing formation pressure through drilling mud, and how kick situations arise when the mud weight is insufficient to offset formation pressure. It explains the role of blowout preventers (BOPs), including annular preventers and ram preventers, in controlling well pressure and preventing blowouts. Additionally, the video describes equipment like choke manifolds, mud gas separators, and trip tanks used to circulate mud and manage kick fluids. The importance of well control training and equipment management to prevent dangerous blowouts is emphasized.

Takeaways

• 😀 Drilling mud exerts pressure to offset the formation pressure, preventing formation fluids from reaching the surface.
• 😀 If the mud weight is too low, formation fluids can enter the hole, causing a kick, which can lead to a blowout if not controlled.
• 😀 A blowout preventer (BOP) stack is used to control formation fluids and prevent blowouts by sealing the well.
• 😀 Subsea BOP systems are used on floating rigs like semi-submersibles and drill ships because the BOP stack is too heavy for the riser pipe.
• 😀 A kick occurs when the pressure from the formation exceeds the pressure from the drilling mud, allowing formation fluids to enter the wellbore.
• 😀 The BOP stack consists of various preventers, including annular and ram preventers, which can seal the well and control kicks.
• 😀 The choke manifold and choke valves help control well pressure and circulate mud and formation fluids out of the well.
• 😀 A mud gas separator separates gas from the mud, with the gas being flared at a safe distance from the rig to prevent accidents.
• 😀 Blind shear rams are used in emergencies to cut through the drill pipe and seal the well, for example, during a hurricane evacuation.
• 😀 The trip tank helps monitor mud displacement when pulling or running the drill string, ensuring the hole remains full of mud to prevent formation fluid entry.

Q & A

What is a kick in drilling operations?

A kick occurs when formation fluids enter the wellbore because the pressure exerted by the drilling mud is less than the formation pressure the drill string is penetrating.

Why is drilling mud important in preventing blowouts?

Drilling mud exerts pressure on formation fluids, preventing them from entering the wellbore. The weight of the mud offsets the formation pressure to keep fluids from coming to the surface.

What is the function of a blowout preventer (BOP) stack?

A BOP stack is used to control the pressure and prevent formation fluids from coming to the surface by sealing off the well when a kick occurs. It consists of several large valves called blowout preventers.

What types of BOP preventers are used on drilling rigs?

There are several types of BOP preventers: annular preventers, pipe rams, blind rams, blind shear rams, and variable bore rams. Each type is used to seal the well in different conditions.

How does an annular preventer work?

An annular preventer surrounds the top of the wellbore in the shape of a ring and can seal the well regardless of whether there is pipe or other tubulars inside the hole.

What happens if formation fluids enter the wellbore?

If formation fluids enter the wellbore, it is called a kick. This can lead to a blowout if not controlled, which can cause damage, injuries, or environmental harm.

What is the purpose of the choke manifold in blowout prevention?

The choke manifold controls the flow of well fluids after the BOP preventers are closed. It adjusts backpressure to maintain the correct pressure at the bottom of the hole, preventing further kick fluids from entering.

Why are blind shear rams used in emergency situations?

Blind shear rams are designed to cut through the drill pipe and seal the well in extreme emergencies, such as when the rig must move off a well due to external threats like a hurricane.

What role does a mud gas separator play in well control?

A mud gas separator separates the gas from the mud in the kick. The gas is flared away from the rig, and the clean mud is returned to the mud tanks for circulation back into the well.

What is the function of a trip tank in drilling operations?

A trip tank is used to monitor and maintain the mud level when drilling or tripping pipe in or out of the well. It ensures that the hole stays full of mud, preventing formation fluids from entering the well.