Drilling Mud

Drilling mud additives is one of the important factors in the success or drilling due to drilling mud itself capable of helping speed in drilling.

Mud is the fluid used in the drilling process. Without fluid mud drilling process will not succeed. Mud which will help speed drilling, increase drilling efficiency, and can guarantee safety.

The properties of mud

1. Density

Density of mud Great will give great hydrostatic pressure on the formation being drilled so that the formation becomes plastic and hard drilled

2. Levels of solids (solid content)

Solid particles that exist preclude contact between the teeth chisel rocks so that will decrease the rate of drilling

3. Viscosity

Large viscosity will reduce turbulence so that cutting clearance decreased and this resulted in a decrease in the rate of drilling

Function Mud drill

1. Lifting the powder with a drill to the surface at a speed of 100-200 fet per minute

2. Cooling and lubricate the drill chisel and drill pipe circuit.

3. Coat the borehole wall with a crust Mud (mud cake)

4. Controlling the formation pressure by raising or lowering the hydrostatic pressure of mud on the state of normal range at 0465 psi / ft

5. Hold the drill powder and material-materiality ballast in the form of a suspension, when circulating Mud suspended. It depends on the strength.

6. Preventing the collapse of the wall lubag

7. reduce the load circuit drill pipe and casing that is covered by rig

8. For media logging

Various drilling mud

1. Fresh water mud

Mud which the liquid phase is fresh water, with salinity <10.000ppm

2. Oil in water emulsion mud (mud emulsion)

At this sludge oil is dispersed phase (emulsion) and water as the continuous phase.

3. Salt water mud (mud salt)

The slurry is used primarily to drill the massive salt (salt Eng) / salt stringer (layers of salt formations)

4. Oil base mud

This sludge containing oil as fasakontinyunya.

5. Barite mud

6. Lumpur foam (foam mud)

7. Lumpur angina (water drilling)

Difficulties in a drilling process will inevitably arise because of their deep hole and is open for a long time to be changes.

Difficulties depending on the drilling mud.

1. Enlargement hole (hole enlargement)

In a sometimes-kadan drilling will terbor a salt formation with considerable depth. Solubility and erosion of this layer can cause berpbesan hole, then a lot of difficulties that will arise such as:

a. the volume of mud that is needed more and less well drill dust removal

b. at the time of cementing the casing requires considerable volumes of cement

to avoid this difficulty, for example in salt formations needed salt saturated mud.

2. sloughing shale (heaving shale)

Some shale formations containing bentonite or clay can be hydrates. These formations will mengadsorb water (swelling) and can fall into the wellbore. It would be a danger because:

a. drill pipe can be wedged (drill pipe sticking)

b. concentration of solids in the slurry to be increased

c. blockage of the drill hole

to avoid this danger among others, that the flow of mud into the annulus arranged laminar and sludge should be repaired its properties, among others:

a. filtrate loss humbled

b. density is increased so that the particles to be quickly raised to the surface

c. change the type of mud with mud and Emultion oil or oil base

3. outburst wild (BLOW OUT)

Wild bursts can occur when high-pressure formations, drilled and the formation pressure greater than the pressure above the mud pools. Then the formation of fluid or gas going in and ride out the hole surface. Flammable gas that can burn the surface installation. Apart from that repeal pipes quickly from drill holes can cause suction action, which in many cases can lead to blow outs. Blow out does not occur suddenly, but there were signs earlier. The signs include:

a. increase the volume of mud in the tub

b. contaminated sludge

c. sudden circulation pressure pumping mud down the speed rises

d. circuit weight drill pipe suddenly

e. missing mud

4. Missing mud

Lost circulation is the loss of part or entirely of mud in circulation is not perfect. This can happen if the density of the mud is too large so that the mud pressure is greater than the formation pressure and formation permeability is too large so that the mud into the fractures-fractures.