Why is the implementation of a drilling fluid important in the drilling of an oil well?

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Hello friends of hive.

On this occasion I want to share with the entire scientific and academic community of StemSocial and the entire community in general a post aimed at explaining the reasons and importance of the implementation of drilling fluid in the drilling of an oil well.

Introduction

In order to understand the fact that drilling fluid is important in drilling wells, we can start by imagining what drilling an oil well would be like without the use of drilling fluid.

If we did not use a drilling fluid or commonly called drilling mud, how would we be able to drag the cuttings made by the drill bit from the bottom of the well to the surface?

One of the natural mechanisms in the drilling of wells is that the bit cuts the geological strata found at the bottom of the well, however this mechanism of action has a wear, that is to say, when drilling there is a wear due to the friction of the bit with the rock cuttings at the depth of the well.

If we do not have a drilling mud that minimizes the effects caused by friction, then we will have to stop drilling at every moment because the bit would have a more pronounced wear.

There are several reasons that make us conclude that it is essential to drill an oil well, however in this introductory mode I am going to explain this last and important reason:

Fluids such as gas and oil are trapped in the subsurface oil reservoirs accumulating a set of pressures ranging from normal to abnormal pressures, so this pressure of fluids such as gas and oil will try to migrate from the subsurface to the surface, If we do not have a drilling fluid that makes a back pressure to not allow these fluids to reach the surface and cause a blowout, we must then employ the use of a drilling fluid with a density according to generate a hydrostatic pressure that is above the pressure values of the formation fluids (gas and oil).

Reasons from an engineering perspective why the use of drilling fluid is important.

The multifaceted nature of drilling fluids allows scientific studies associated with the hydraulics of such fluids and provide engineering with the best applications using different types of drilling fluids, all depending on the drilling needs of the well to be drilled.

For example, if we are going to drill a well in its first feet of depth, it is propitious to use a drilling fluid based on water and bentonite, since with this type of fluids we would not be contaminating the fresh water aquifers.

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Drilling fluids, apart from fulfilling all the functions that allow drilling to be carried out optimally, also allow studies related to all the geological information found in the subsoil, as it serves as a means of transport for sonic, electronic and acoustic profiles that run in the bottom of the well, all with the intention of making an interpretation to know if there is hydrocarbon in a particular area of a possible oil field.

With the use of drilling fluids has also allowed throughout the history of the oil industry and drilling to study the behavior of drilling fluids and their influence on the drilling of wells based on previous knowledge that already had, an example of this is for example the knowledge that has been had since antiquity about hydrostatics, that is to say of the behavior of the fluids in static state, in the drilling of wells sometimes the pumps that pump the drilling fluid are turned off, the drilling fluid remains inside the hole in a static form, this allows to quantify which is the pressure that exerts on the walls of the bottom of the hole, and how some thixotropic properties can vary as they remain static and without circulation (dynamic state).

Conclusion

When the oil industry was in its infancy drilling wells were drilled using a technique called percussion drilling, where drilling fluid is not used, at that time there were many problems to control well pressures, several explosions occurred, and only found a solution through the rotary drilling technique where if you can use a drilling fluid that is prepared in the mixing tanks and comes from the active tanks and is pumped by mud pumps, circulating it inside the drill pipe until it reaches the bottom of the well and dragging the drill cuttings from the bottom to the surface, cooling and lubricating the drill bit, creating a smooth and permeable plaster on the walls of the well, but above all generating a back pressure to the formation fluids and thus avoiding a blowout of fluids such as gas and oil and an explosion at the surface.

If we take into account the degree of importance of the drilling fluid, more than allowing to optimize the drilling of an oil well, the greatest importance lies in the fact that it can protect human lives by controlling pressures in the well.

Reference consulted and recommended

Drilling fluid

Rheology

Hydrostatics

ACCORDING THE CHANGE OF DRILLING FLUID TO UNDERSTAND UNDER WELL CONDITION