Exploration drilling - activities aimed at finding raw materials in the bowels of the earth. At the beginning of the 19th century, France was searching for water in this way. In the 50s of the same century with the help of exploratory drilling looking for oil.
Today exploratory drilling is carried out by powerful and complex equipment.
For the destruction of the rock a special chisel is used. It joins the drill pipes. During exploratory drilling The bit wears out, accordingly, it needschange. For this, the pipe string rises to the top, the worn out element is removed, a new one is wound. After that, the whole column descends into the bowels of the earth again.
The chisel has a larger diameter than the chimney. After it passes through the formation of rock between it and the pipe there is a gap. With the help of powerful pumps, the drilling fluid is fed into the pipes. It descends first downwards, and then climbs up the annulus. At the top, it is cleaned of rock and re-injected into the well. These works are performed by qualified specialists - drilling drillers for exploration drilling. Of course, a whole team works on one site.
In 1922 the Soviet engineer Kapelyushnikov proposed a new method exploratory drilling - turbine. The engine dropped down to the bottom of the borehole, due to which the chisel was rotated. Due to this innovation, there was no need to drive the entire column of pipes, which significantly saved energy.
Subsequently, the turbine exploratory drilling repeatedly improved. Today the turbodrill is a very complicated unit, the length of which is about 10 m. Each stage of the machine is equipped with 2 disks with profiled blades. One of them is a stator. It is fixed in the body of the unit. The second is a rotating rotor. The turbo-drill is driven by the drilling fluid injected into the well under pressure. He washes out the remains of the rock and cleans the rotor blades.
At each section of the unit a relatively small power develops. However, the aggregate force is sufficient to destroy even the hardest rocks.
Its quality is given increased attention. The drilling mud performs several functions. First of all, he lifts the debris of the destroyed rock to the surface. In addition, due to it, the turbo-drill is driven into rotation, the chisel is cooled.
Previously, as the drilling mud actedwater. Currently, it is not used. It is caused by the following. Water is really capable of carrying the destroyed rock to the surface. However, if the process stops, all debris will begin to settle down. After a while they fill the shell space. As a result, all equipment will remain under the wreckage of the rock. Pull out the unit is almost impossible. All this will entail serious financial losses, since the cost of the machine and its components is several million rubles.
To avoid such situations,a special clay solution based on clay powder. It does not allow the rock to settle in the event of suspension of drilling. After the process is resumed, the sludge (broken rock) will again go up.
When drilling in the bowels may be present different layers (oil, water, gas). One of the key conditions of the process is ensuring their immunity.
Suppose a 4-kilometer hole is drilleddiameter 30 cm. Conventional sealing from above will lead to very dangerous consequences. From different layers of the mixture will begin to fill the space. Then, from the reservoir in which the highest pressure, the substances will penetrate into other levels. They, in turn, can contain water layers close to the surface. As a result, oil or gas will penetrate into lakes and rivers, urban reservoirs.
To prevent such consequences, in the processDrilling the wellbore is filled with drilling mud. It prevents the penetration of fractions from occurring strata into the formed space. But in order to achieve this, a solution of a certain density is needed, and he himself must not penetrate into the seams.
As mentioned above, several workers are involved in drilling. The brigade includes not only highly qualified drillers, but also auxiliary personnel.
Driller assistant:
The duties of the employee also include participation in the elimination of accidents and complications.
Assistant driller should know:
Since the tasks of the employee includemaintenance of the units, he must know the rules for preparation, cleaning, treatment of solutions, their main physical and chemical parameters, the rules for preparing the pipes for descent, the diagrams of the drilling rig, the operating manual for blowout equipment.