Abstract: The present invention relates to the completion of wells and, more particularly, it relates to a method of drilling a productive bed.The herein disclosed method of drilling a productive bed comprises the tapping of the bed roof using a starting flushing fluid and the determination of the redox potential value at the moment of tapping the bed roof, and subsequent replacement of the starting flushing fluid with a fluid having redox potential value and sign equal to those of the productive bed rock.

Abstract: A method for separating solid phase from drilling mud, comprising forming from drilling mud and adhesive layer on a rotary closed curvilinear surface partly placed in the drilling mud, with subsequent feeding of an ionized gas jet along a tangent line to the adhesive layer, the gas jet entraining and removing solid phase particles from the drilling mud. The linear velocity of the adhesive layer in the zone of its contact with the gas jet is controlled by changing the velocity of the gas jet.

Abstract: A method of maintaining preset parameters of a drilling mud delivered into a well in the process of drilling in which a value of the oxidation-reduction potential (redox potential) of the drilling mud is continuously measured at the inlet and outlet of the well. The obtained results are compared and a variation in the value of the redox potential of the drilling mud at the well outlet with respect to the value of the redox potential at the well inlet is registered. In case of any variation in the content of oxidation products in the drilling mud at the well outlet, the drilling mud is subjected to a unipolar electric treatment at the well inlet and the content of reduction reaction products in the drilling mud is increased until the preset value of the redox potential of the drilling mud is restored at the well outlet.

Abstract: A method for controlling the dispersing of solids in drilling mud, consisting in that mud mineralization value is measured continuously until it stabilizes itself in the course of the dispersing, the variation of the mud mineralization value being used to determine the concentration of particles of the drilling mud solid phase.

Abstract: A method of determining the depth of occurrence of a chemically aggressive bed in the course of drilling a well with the use of a drilling mud, wherein there is measured preliminarily the value and direction of the redox potential of the drilling mud injected into the well, whereupon the walls of the well are stripped of the mud cake and an additional portion of the drilling mud featuring its redox potential differing as to the value and direction from the redox potential of the drilling mud situated in the well, is prepared.

Abstract: An apparatus for cleaning drilling mud, wherein a straightflow hopper (1) has a pipe (2) for collecting drillings deposited from the drilling mud, accommodating a device (3) for removing the drillings. The device for removing the drillings comprises two shutters (4, 5) provided at the ends of the pipe (2) for collecting the drillings separated from the drilling mud, which are connected to one another and coupled to an actuator (8) for turning the shutters for alternately shutting-off the cross-section of the pipe (2).

Abstract: A method of continuously logging a borehole in the course of drilling with the use of a drilling mud. According to the invention, the drilling mud fed into the borehole is subjected to unipolar electric treatment, with simultaneous measurement of the oxidation-reduction potential of the drilling mud. This value is maintained substantially constant at a given magnitude. The value of the oxidation-reduction potential of the drilling mud returning from the borehole is continuously measured and compared with the given value of the oxidation-reduction potential of the drilling mud fed into the borehole. Using the difference between the two values, the mineralogic composition of the rock adjacent to the bottom of the hole is determined for a given moment, by comparing this difference with the known in advance normal oxidation-reduction potentials of minerals.

Abstract: A method for the determination of depth of a fluid-saturated stratum and type of a fluid, such as mineralized water, oil and gas released during drilling, comprising pretreating the drilling mud before feeding to a well so as to maintain the original value of its redox potential at a stable level. The supply of the drilling mud to the well is suspended upon a change in the redox potential indicating to the presence in the drilling mud of a fluid saturating the stratum. After a certain time lapse the supply of the drilling mud to the well is renewed. The time of restoration of the drilling mud supply to the well and the time of appearance of the batch of the drilling mud diluted with the fluid saturating the stratum are marked and are used to determine the depth of the stratum. The redox potential of the batch of the drilling mud saturated with the fluid is measured and compared to known normal values of redox potential to determine the type of the fluid.

Abstract: A method of monitoring structural and mechanical properties of drilling mud and a device for realizing this method includes the determination of the viscosity of drilling mud via a viscosimeter and the determination of the shear strength of the mud via a shear strength measuring instrument, both of which have driven sensitive elements immersed in the drilling mud. The signals of the sensitive elements are converted by converters to indications of the parameters being measured and are compared. The sensitive elements are connected to the same pole of a power source. An electrode immersed in the drilling mud is connected to the opposite pole of the power source. The current flowing between the electrode and the sensitive elements is measured and, when the current is stabilized, the converters produce signals proportional to the viscosity and shear strength of the drilling mid.

Abstract: The method of separating the solid phase in a drilling mud includes forming from the drilling mud an adhesion layer 2 on a rotated curvilinear closed surface 3 partly projected into the drilling mud. Then a portion of this adhesion layer is separated onto another rotated curvilinear closed surface 5 positioned to contact a portion of the adhesion layer 2. The respective linear speeds of the adhesion layer 2 and of said another rotating closed curvilinear surface 5 in the area of their contact are selected to be substantially equal. The method of the invention provides for regulating the separation of the solid phase in drilling mud within a wide range depending on the mineralogical composition thereof.

Abstract: An apparatus for electrokinetically separating drilling mud into liquid and solid phases comprising a casing (1) having an inlet (2) for drolling mud and outlets (3,13) for separated phases thereof and accommodating electrodes connected to the negative terminal and to the positive terminal, respectively, of a d-c source (8). The electrode connected to the negative terminal of the d-c source (8) comprises a conveyor screw (4) which has a cylindrical portion (5) and an adjacent conical portion (6). The casing (1) functions as the electrode connected to the positive terminal of the d-c source (8) and has respective cylindrical (10a, 10b, 10c) and conical (11) portions. The outlet (13) for solid phase of drilling mud is provided at the end of the conical portion (11) of the casing (1). There is provided a receptacle (14) for collecting solid phase of drilling mud communicating with the outlet (13) for solid phase of drilling mud provided in the casing (1).

Abstract: A method for separating solid phase from drilling mud, comprising forming from drilling mud an adhesive layer 4 on a revolving closed curvilinear surface 3 by partially submerging it in the drilling mud and forming from a treatment liquid (5) an adhesive layer (7) on another closed curvilinear surface (6) which is caused to rotate in the direction opposite to the rotation direction of the first curvilinear surface (3). Both closed curvilinear surfaces (3, 6) are arranged in such a manner that their adhesive layers (4, 7) penetrate one another at a depth sufficient for the adhesive layer (7) of the treatment liquid to take-off coarse solid phase particles from the adhesive layer (4) of the drilling mud. Linear velocities of the adhesive layers (4, 7) are chosen in such a manner that the resultant centrifugal forces be equal to or lower than the centripetal forces.