Petroleum engineering is the engineering that is in charge of all the design in the exploration, drilling and production of an oil well, in the case of drilling a well there is a very important engineering involved which is the design of the drilling fluid.
The drilling of an oil well is almost impossible to perform without the use of a drilling fluid, because the drilling fluid in the drilling of an oil well is like blood in the human body, if the blood does not circulate through the human body can not meet some basic conditions and the human being can die, in the same way happens in the well, if the well is not drilled pumping fluid, drilling dies because it can not meet certain functions that provides us with the drilling fluid.
Those of us who study petroleum engineering and work in the drilling of oil wells know that the drilling fluid is known as drilling mud, and that it is used in the drilling of wells to facilitate well construction operations, which can be water, oil and/or natural gas.
Drilling fluids have a very varied classification, ranging from water-based drilling fluids to the point that oil-based drilling fluids can be used, aerated fluids are also used for when you have to drill low balance, i.e. you have to formulate drilling fluids whose density values generate hydrostatic pressures that are lower than the formation pressure.
Why drill with drilling fluids?
Drilling with a drilling fluid is done because the functions provided by drilling with a drilling fluid give us advantages over drilling without using drilling fluids.
An example of this is that when we drill an oil well with a drilling fluid that has a specific density, this density will exert a pressure on the walls of the well and this can prevent formation fluids such as oil and gas can enter the well while it is being drilled.
Another advantage is that when drilling with a drilling fluid it is possible to extract the drill cuttings that are produced when the drill bit cuts the rocks of the formation in the subsoil, since the drilling fluid must contain chemical additives that allow to generate a viscosity such that when the drilling of the well is stopped for whatever reason, the cuttings can be suspended during those small pauses that can be made in the drilling of the well.
We cannot ignore the friction produced by the drill bit and the rock in the subsurface, such friction generates heat, that excessive heat without anything to cool the system can wear the drill bit teeth and cause the drilling of the well to stop, however when we use a drilling fluid we achieve that it can cool and lubricate the bit in the process of drilling the well.
The selection of the drilling fluid cannot be done randomly or without any previous study and design, reason why the drilling fluid to be used in the drilling of a well must be selected under strict design parameters in which it is considered to avoid damaging the rock formation in the subsoil and that the corrosion or damage of the drill bit is as minimal as possible.
Recommended reference