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 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: A method for the preparation of drilling mud wherein solid and liquid phases of drilling mud are mixed in a vessel (2) to obtain a homogeneous suspension. After the mixing the drilling mud is caused to pass under pressure through apertures (5 or 6) provided in a stirring member (3 or 4) of a piston type, the apertures being of a diameter which is greater than maximum size of an individual solid phase particle but smaller than the diameter of aggregates of particles, to prepare dispersed drilling mud.

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.