SU1154454A1 - Method of modulating noise in drill string in turbo-drilling of holes - Google Patents

Abstract

METHOD FOR MODULATION OF NOISE drillstring turbine drilling, based on the inhibition zone formation interference of shock pulses, characterized in that, in order to increase the reliability of measurement information by providing the wave breaks, aligned slotted perforations reactive resonance chambers slit perforated pipes embedded in the shaft The turbine ones briefly expand the flow area for the flushing fluid pipe moving along the channel, with the amplitude of oscillation of elastic waves up to a wave pause. menshaets by changing the acoustic energy density in this portion of the drill pipe.

Description

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4a O1 4 The invention relates to the field of technical acoustics and can be used to obtain in-depth information in the process of drilling oil and gas wells. Methods are known for modulating a signal for transmitting technological information about the parameters of a drilling mode along a string of drill pipes, flushing fluid, and rocks. A known method of modulating the pressure of the clay solution for transmitting information via a hydraulic communication channel is based on the short-term closure of the channel with the creation of a pressure differential in the flushing column of a liquid using GD hydroturbators. The disadvantage of this method is the presence in the communication channel of the fur, excited by the work of the bit. The closest to the technical essence of the present invention is a method of noise modulation in a drill string during turbine drilling of wells, based on the formation of a suppression zone behind impact pulses C2j. A disadvantage of the known method is a decrease in the reliability of information associated with a decrease in the amplitude of elastic oscillations on the receiving side with an increase in the depth of the well. The purpose of the invention is to increase the reliability of measuring information by creating wave pauses. The goal is achieved by the method of modulating noise in a drill string during turbine drilling, based on fy on the formation of a suppression zone behind impact pulses, combined slit perforations of reactive resonant chambers with slit perforations of a pipe embedded in the turbine shaft, and expanding the short-term volume a passage section for a conveyer fluid moving along the channel, the oscillation amplitude of elastic waves being reduced to a wave pause due to a change in the density of sound energy by this ohm section of the drill pipe. The essence of the invention is that, by changing the flow area, for example, expanding it, in a certain section of the pipeline, the density of sound energy 4 in the channel decreases. Moreover, the sonic energy is converted into heat due to nonlinear effects in the places where the cross section changes. The frequency modulation interval for the resonant volume is determined by the formula where S is the cross-sectional area of the pipeline; t is the resonator length; V is the cavity volume. The magnitude of the oscillation amplitude decay for the resonator is found from the following ratio R (t / ir), where t is the wave transmission coefficient, For a longitudinal wave, where 6 is the ratio of the resonator volume sections h2 to the pipeline section h, and is determined by the formula. The frequency spectrum of the noise, experimentally obtained by serials from bzph wells, is in the range of 0-400 Hz. To modulate the oscillations with the formation of a wave pause, the frequency spectrum of the noise is divided into subranges of 100 Hz and for each frequency with a given bandwidth, four resonant chambers with a variable volume are inserted into the hydrochannel. The number of frequency bands and cameras can be increased. Fig, 1 shows a device that implements the method; in fig. 2 shows section A-A in FIG. 1 (2 "- arbitrary position of slotted perforations), (26th combination of slotted perforations), The device includes a body 1 of the sub, resonant chambers 2-5, a turbine shaft 6, a perforated pipe 7, a slotted perforation 8 of the pipe, slotted perforations 9-12 volume chambers ( Fig. 25 shows the alignment of a slit perforation 9 of the volume chamber 2 with a slit perforation 8 of the pipe 7 with an internal hydrocore. The device operates in the following manner.

With each revolution of the turbine shaft; the perforation 8 of the tube 7 is aligned with the slit perforations of 9-12 resonant chambers 2-5; As a result, the short-term alignment of the perforations (Fig. 25} increases the cross-section of the passage through the hydrochannel, with reactive chambers each tuned to its own strip

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frequency modulates the frequency spectrum of the noise with the formation of a wave pause. The proposed method in its implementation will allow to increase the mechanical speed and penetration of the bit due to a significant increase in the accuracy of the measurement information and the drilling process in a rational mode.

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FIG. 2a

Claims (1)

METHOD OF NOISE MODULATION IN A DRILLING CORE DURING TURBINE DRILLING OF WELLS, based on the formation of a zone for suppressing interference behind shock pulses, characterized in that, in order to increase the reliability of the measurement information by creating wave pauses, they combine slotted perforations of reactive resonance chambers with slotted perforation the turbines built into the shaft briefly expand the volume of the flow cross section for the washing fluid moving along the pipe channel, and the amplitude of the oscillations of the elastic waves before the wave break shaetsya by changing the acoustic energy density in this portion of the drill pipe. g