Топырақ қазу жұмысында қолданылатын сұйықтықтар

Aid for drilling boreholes into the ground
fluids used when drilling a well

In geotechnical engineering, drilling fluid, also known as drilling mud, is used to aid the drilling of boreholes into the earth. Used while drilling oil and natural gas wells and on exploration drilling rigs, drilling fluids are also used for much simpler boreholes, such as water wells. The two main categories of drilling fluids are water based muds (WBs), which can be dispersed and non dispersed, and non aqueous muds, usually called oil based muds (OBs). Along with their formatives, these are used along with appropriate polymer and clay additives for drilling various oil and gas formations. Gaseous drilling fluids, typically utilizing air or natural gas, sometimes with the addition of foaming agents, can be used when downhole conditions permit. The main functions of liquid drilling fluids are to exert hydrostatic pressure to prevent formation fluids from entering into the well bore, and carrying out drill cuttings as well as suspending the drill cuttings while drilling is paused such as when the drilling assembly is brought in and out of the hole. The drilling fluid also keeps the drill bit cool and clears out cuttings beneath it during drilling. The drilling fluid used for a particular job is selected to avoid formation damage and to limit corrosion.

They are classified based on their fluid phase, alkalinity, dispersion and the type of chemicals used.

Freshwater mud: Low pH mud (7.0–9.5) that includes spud, bentonite, natural, phosphate treated muds, organic mud and organic colloid treated mud. high pH mud example alkaline tannate treated muds are above 9.5 in pH. Water based drilling mud that represses hydration and dispersion of clay. Water based muds are the most commonly used type of drilling fluids. They are made from water and various additives including clays, polymers, and weighing agents. WBM is primarily used in shallow wells and is effective in preventing the swelling and disintegrating of the shale formation. – There are 4 types: high pH lime muds, low pH gypsum, seawater and saturated salt water muds.

Low solids mud: These muds contain less than 3–6% solids by volume and weight less than 9.5 lbs/gal. Most muds of this type are water based with varying quantities of bentonite and a polymer. Emulsions: The two types used are oil in water (oil emulsion muds) and water in oil (invert oil emulsion muds). Oil based mud: Oil based muds contain oil as the continuous phase and water as a contaminant, and not an element in the design of the mud. They typically contain less than 5% (by volume) water. Oil based muds are usually a mixture of diesel fuel and asphalt, however can be based on produced crude oil and mud

Synthetic based Muds (SBM): Synthetic based muds are made from synthetic fluids and are used in deep wells with extreme temperatures. SBM has excellent lubricating properties and is less toxic than OBM. Air and Foam based Mud: Air and foam based muds use air or nitrogen to create a foam that carries the drill cuttings to the surface. These types of drilling fluids are used in wells where the formation is highly porous and prone to caving. High density Muds:High density muds are used in wells with high pressures and temperatures. They are made from barite and other weighing agents and are used to control the pressure in the well and prevent blowouts. Non damaging Muds: Non damaging muds are designed to prevent damage to the formation being drilled. They are typically used in wells where the formation is susceptible to damage from drilling mud

"Mud engineer" is the name given to an oil field service company individual who is charged with maintaining a drilling fluid or completion fluid system on an oil and/or gas drilling rig. This individual typically works for the company selling the chemicals for the job and is specifically trained with those products, though independent mud engineers are still common. The role of the mud engineer, or more properly drilling fluids engineer, is critical to the entire drilling operation because even small problems with mud can stop the whole operations on rig. The internationally accepted shift pattern at off shore drilling operations is personnel (including mud engineers) work on a 28 day shift pattern, where they work for 28 continuous days and rest the following 28 days. In Europe this is more commonly a 21 day shift pattern. In offshore drilling, with new technology and high total day costs, wells are being drilled extremely fast. Having two mud engineers makes economic sense to prevent down time due to drilling fluid difficulties. Two mud engineers also reduce insurance costs to oil companies for environmental damage that oil companies are responsible for during drilling and production. A senior mud engineer typically works in the day, and a junior mud engineer at night. The cost of the drilling fluid is typically about 10% (may vary greatly) of the total cost of drilling a well, and demands competent mud engineers. Large cost savings result when the mud engineer and fluid performs adequately. The mud engineer is not to be confused with mudloggers, service personnel who monitor gas from the mud and collect well bore samples.