SU716013A1 - Acoustic insulator for acoustic well-logging apparatus - Google Patents

Description

The invention relates to the field of geophysical exploration of wells and can be used in acoustic equipment 5 logging wells, cased with pipes of small diameter or equipped with fountain fittings.

Acoustic insulators are known, containing a soundproofing section in the form of a metal pipe with introduced defects covered with soundproofing material [1], ₍ However, such insulators, providing high-quality registration of elastic 'waves in wells of normal diameter, are not implemented in small-sized devices designed for' Investigations of the small diameter of FeF a .. (60 mm and less), 20

Known acoustic insulators made of elastic material. A bed containing a reinforcing fibrous sound-absorbing substance [2] has 25 high insulating properties and provides the possibility of their use in small diameter wells.

However, the excessive flexibility of such an Insulator eliminates the possibility of confident centering of the probe in the pipes,

Acoustic insulators are known, containing alternating elements with different acoustic stiffnesses [3] and [4], which make it possible in principle to create a device for small diameter wells.

The closest in technical essence to the proposed device is an acoustic isolator for borehole acoustic logging tools containing alternating elements with different acoustic stiffnesses and connector-. nye elements [4],

The outer coating in the insulator is made of a material with low acoustic rigidity, the contacting surfaces of elements with different acoustic rigidity are made conical with different taper angles with respect to the axis of the insulator.

The main disadvantage of this insulator is the impossibility of regulating yzgibnoy rigidity in its middle part.

'To ensure normal patency device in bent rub / bang little of the diameter (40 mm), while ensuring steady centering needed optimal gybpr _minutes maintaining sufficient tensile strength · In addition, the presence of a metal holder part in the form of a tube extending along the entire length insulator and being a monolithic wave '', reduces the soundproofing ability of the insulator.

The purpose of the invention is the “-provision of optimal transverse stiffness” of the insulator and the increase of effective diameter with a diameter of less than 40 mm. The goal is achieved by the fact that in the proposed device, elements of a material with a larger acoustic gesture '' '' 'bone are filled in the form of cylinders and nozzles with stepwise changing diameters, and' elements of a material with less acoustic rigidity 'are made in the form of bushings, covering the nozzles with an external lateral groove ~ from the ends, moreover, the careful cylinders are placed on the lateral bushings with the outer surface of the insulator каждый each cylinder is connected to the nozzle in the section with the maximum diameter, connecting elements are located on each nozzle and uyastke 'with' 'minymalygm diameter.

The drawing shows the proposed. “Insulator.,

..... consists of end Ϊ, 2 and intermediate 3 metal 'nozzles', between which the soundproof bushings 4 and thrust washers 5 are placed. On the outer 'diameter of the nozzles the soundproof bushings b are put on, “ ^,, ' ^ '*' 1 ^ B {>e'''9 _{soundproofing of the} cutting logs 'from the outer cylinder 7. On the outer diameter of the' cylinder, annular grooves with conical lateral surfaces are made. The connection of the pipe through the * '”star ^' FyölLyuyushchy bush 6 with an external cylinder is carried out through the washer 45 with a conical nut 9. Moreover, it allows you to regulate the needs of the Insulator. Before operation, the acoustic insulator is assembled from a number of sections, the design of which is described above, and their number is determined by the specified length of the insulator. They do not have direct contact between metal parts, which allows to achieve large · 3 ^^ Χ3ϊηΗη high-frequency oscillations. In turn, the sections are connected using a threaded connection of the pipe (one section) - cylinder (subsequent section), 'which makes it possible to increase the effect of dissipation, energy . .

The advantage of the invention is the acoustic absorption attenuation of high-frequency oscillations even in a small-diameter insulator; the possibility of 'increasing' or decreasing 'the length of the insulator while maintaining its sound-insulating properties increased strength, as well as the possibility of adjusting the transverse stiffness by changing the' tightening torque of the nuts, which allows us to obtain the optimal value of elastic stiffness' sufficient to maintain the shape of the device when the inclination of the well to 4.0 ° and at the same time allowing the device to bend when passing with great effort the tightening zone in complicated wells.

Claims (2)

The invention relates to the field of geophysical well surveys and can be used in acoustic logging equipment for wells that are cased with small diameter pipes or equipped with wellhead valves. Acoustic insulators containing soundproof sections in the form of a metal pipe with defects introduced, covered with sound insulating material 1 are known. However, such insulators, providing a high-quality recording of elastic waves in boreholes of conventional diameter, are not implemented in small-sized devices designed for well drilling. small diameter a .. (60 mm or less). Known acoustic insulators WAVER from elastic material containing reinforcing fiber sound absorbed in sound substance 2, have high myisolation properties and provide the possibility of their use in wells, small diameter ,. ., However, the excessive flexibility of such an Insulator precludes the possibility of confident centering of the probe in the pipes. Acoustic isolators are known that contain alternating elements with different acoustic stiffnesses that make it possible in principle to create an instrument for wells of small diameter. The closest in technical essence to the proposed device is an acoustic isolator for borehole acoustic acoustic logging devices, containing alternating elements with different acoustic rigidity and connector-. 4, The outer coating in the insulator is made of a material with low acoustic rigidity, the contacting surfaces of the samples with different acoustic rigidity are made conical with different angles of taper with respect to the axis of the insulator. The main disadvantage of this insulator is the impossibility of controlling the flexural rigidity in its middle part. 7 In order to ensure the normal pro- ductivity of the device in curved pipes of a low diameter (less than 40 mm), a reliable centering is necessary, while maintaining sufficient strength for the discharge. In addition, the presence of a metallic support part, in the form of a pipe, extending along the entire length Isolator and monolithic waveguide reduces the sound insulation capacity of the insulator. The purpose of the invention is to provide optimal transverse stiffness and insulator and increase the efficiency of insulation with a net of less than 40 mm. The goal is achieved by the fact that, in the proposed device, elements from a material with a greater acoustic gesture are made in the form of cylinders and - -toyok with stupidly varying diameter, and alematite from a material with a lower acoustic stiffness of bcdl 1en in the form of a bristle, encompassing from the outer side on the “rhGGo & -ti and from the ends, and the cylinders are placed on the side bushings from the outside surfaces of the insulator and the days of the cylinder are articulated with a pipe at the maximum diameter of each other, and the connecting elements are located on each Oh n & nauchastuka tube with a minimum diameter. . The drawing shows the proposed i-zol. ,,; ..:.:., .......- ,, .. The isolator consists of end 1, 2 and intermediate 3 metal pipes, -mem which are located insulating sleeves 4 and thrust washers 5. ria outer diameter of the nozzle are fitted with sound insulating sleeves b, and they isolate the nozzle from an in-Cylinder 7. On the outer diameter of the Schlindra cut-off ring-shaped grooves with conical boccro jochoctochocktoctochomectochocktoctococtococto The connection of the nozzle through the - ffp tfStJjrapy} 0 # e bushings with internal - ilinda & m "is effected through the washers 8 with a cone-shaped nut 9. At the same time, the insulator can be adjusted to the required size of the insulator. Before operation, the acoustic insulator is assembled from a series of sections, the structures of which are described / above, and their number is determined by a given insulator length. They do not have direct contact between the metal and parts of Iv6l, which allows to achieve large high-frequency oscillations. In turn, the connection section with a threaded connection of the pipes (one section) - the cylinder of the subsequent section), which makes it possible to increase the effect of dispersion, energy . .-, The design of the invention is a large amount of attenuation of high-frequency lib 1 even in small diameter btSe isolate; the possibility of magnitude or reduction of the length of the torso1 with the preservation of its sound insulation of ionic properties; Increased strength, also ATTENTION of adjusting back stiffness by changing the force of the nuts, which allows you to learn the optimum elastic stiffness, which is sufficient to maintain the shape of the device when tilting the wells, to 4.0 ° and at the same time allowing the device to bend when passing with great effort zat zhk zones in complicated wells. : Formula of the invention Acoustic Isolation of Acoustic Logging Borehole Instruments, containing hardware elements made of materialoses — unraced acoustic stiffness i and connecting elements, and so on, to ensure optimal lateral stiffness of the insulator and increase the efficiency of insulation, elements from a material with a greater acoustic stiffness are made in the form of cylinders and pipes with stepwise varying diameter, and elements from a material. with lower acoustic stiffness, they are made in the form of sleeves / female branch pipes with external outer side surfaces, and the cylinders are placed on the side bushes from the external surface of the insulator and each Cylinder is connected to the maximum diameter pipe, and the connecting elements are located on each branch pipe. On a plot with a minimum diameter. Sources of information taken into account in the examination. 1. Author's certificate of the USSR 314175, cl. G 01 V 1/40, 1969. 2.Avsk certificate of the USSR No. 419830, cl. G 01 V 1/40, 1972. 3.fiFSdpcKOe certificate of the USSR 343712, cl. G .01 V 1/40, 1971. 4. USSR Author's Certificate No. 303422, cl. G 01 V 1/40, 1969 (prototype) ... .