Page 6 - SEG - First issue

Academic Articles

III- Drilli

Drilling fluids is a term used in
petroleum engineering which

means a heavy viscous fluid

mixture that is used in oil and
gas drilling operations to

achieve a number of critical
Function like :

- Removal of cuttings from the

bottom of the hole
- Suspend cuttings and weight

material
-Transport cuttings and gas to

the surface

- Cool and lubricate the bit and
drill string

- Add buoyancy to the drill

string
- Control subsurface pressures So from all of it's functions we can deduce it's critical to

helps in preventing the the drilling operation. it is also crucial to understand

collapse of unstable strata - what goes in the mud and how to use it efficiently .
- stops the intrusion of water most of the time drilling mud are made mainly of water

from beds that have water whether it is fresh or saline or brine( prepared or naturally
occurring ). water based mud is used for that are less

demanding wells like medium depth conventional vertical
wells. water based mud contains clay usually bentonite
so it gives the water enough viscosity to hold the rock
fragments to the top .

Bentonite

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