Ultrasonic rotary drift size gauge tool

Abstract

The ultrasonic rotary drift size gauge tool comprises a motor, a rotary drift size gauge tool body, an ultrasonic generator and an ultrasonic transducer, an inner shaft sleeve of the rotary drift size gauge tool body is connected with the ultrasonic transducer through threads, bearings are installed at the two ends of an inner shaft, an outer shaft is installed on the bearings, the outer shaft is connected with a motor rotor through a connecting key, and a centralizing sleeve is installed on a motor shell. A plate spring is installed on the outer shaft, a blade is installed on the plate spring, and a lower centralizing sleeve is installed on the inner shaft. According to the method, the descaling effect is more efficient and convenient, the shaft cleaning efficiency is high, ultrasonic waves have a certain blockage removal effect on a perforation compaction zone while descaling is conducted, and the stratum permeability is improved; the device is simple in structure, firm, durable, safe, reliable and convenient to maintain, and the well opening rate of the gas well is increased.

Description

Technical Field

[0001] The present invention relates to the field of exploration and development operations, and particularly to an ultrasonic rotary hole opener. Background Art

[0002] At present, a large number of solid blockages such as black flaky, sandy mud mass, and grayish-white particles have appeared in the development of some production wells in Dongping and Jianbei gas fields, which has brought great difficulties to the normal data testing, sand face exploration, liquid level exploration and other conventional testing operations of gas wells. Due to the appearance of blockages, the testing tools cannot be smoothly lowered to the expected position, or the testing tools are stuck and difficult to salvage. The blockages will also cause a sharp decrease in the production and pressure of gas wells, seriously affecting the production of individual wells and the development of gas reservoirs. The gas wells need to frequently replace the string operations, resulting in a sharp increase in development costs.

[0003] Regarding the scale samples of individual wells in Dongping and Jianbei gas fields, indoor experiments were carried out to detect and study the composition of the scale samples, and the formation mechanism of the scale samples was clarified. On this basis, research on the plugging removal fluid formula for different types of blockages was carried out, with a long cycle, slow effect and high cost. The scale samples of 6 scaling wells in Jianbei and Dongping blocks have great differences and have the following characteristics: pipe wall scale samples: the shape is flaky, the crystallization is dense, and the main components are barium sulfate, strontium sulfate, calcium sulfate, calcium carbonate, and clay minerals; bottom hole scale samples: the shape is massive, the structure is loose, and the main components are calcium carbonate and calcium sulfate.

[0004] During the production process of gas wells, substances in the formation enter the wellbore along with the gas flow and formation water. During the lifting process, the substances change and form precipitates attached to the pipe wall of the gas well tubing, resulting in changes in the tubing flow channel. The precipitates attached to the pipe wall are dispersed in flakes on the pipe wall, causing unstable production of the gas well, blockage of the flow channel, inability to lower downhole testing tools, inability to measure downhole data, affecting gas well data acquisition and data analysis, and affecting gas reservoir development and adjustment.

[0005] During the production process of gas wells, substances in the formation enter the wellbore along with the gas flow and formation water. During the lifting process, the substances change and form precipitates attached to the pipe wall of the gas well tubing, resulting in changes in the flow channel. The precipitates attached to the pipe wall are dispersed in flakes on the pipe wall, causing unstable production of the gas well, blockage of the flow channel, inability to lower downhole testing tools, inability to measure downhole data, affecting gas well data acquisition and data analysis. Summary of the Invention

[0006] The purpose of the present invention is to provide an ultrasonic rotary hole opener in view of the deficiencies of the prior art. The present invention organically combines ultrasonic technology with the hole opener, and uses the dual effects of ultrasonic descaling and mechanical descaling to achieve the purpose of wellbore cleaning.

[0007] The technical solution of the present invention is solved as follows:

[0008] An ultrasonic rotary hole opener includes a motor, a rotary hole opener, an ultrasonic generator, and an ultrasonic transducer. The inner bushing of the rotary hole opener is threadedly connected to the ultrasonic transducer. Bearings are installed at both ends of the inner shaft, and an outer shaft is installed on the bearings. The outer shaft is connected to the motor rotor through a coupling key. An upper centralizer is installed on the motor housing, a leaf spring is installed on the outer shaft, a blade is installed on the leaf spring, and a lower centralizer is installed on the inner shaft.

[0009] The ultrasonic transducer consists of an ultrasonic vibrator, a positive wire, a negative wire, and a conductor. The electrical connector is connected to the conductive ring of the ultrasonic transducer through a power wire installed in the connector hole of the ultrasonic transducer. The conductive ring of the ultrasonic transducer is connected to the ultrasonic vibrator through a wire. The current generated by the external power supply is sequentially transmitted to the ultrasonic vibrator through the electrical connector of the ultrasonic generator, the power wire, the positive and negative conductive rings, and the wire. The ultrasonic vibrator converts electrical energy into ultrasonic waves of corresponding frequencies.

[0010] The center of the inner shaft is hollow to facilitate the passage of wires and is connected to the ultrasonic transducer by threads.

[0011] The outer shaft is connected to the motor rotor shaft through a coupling key.

[0012] The output electrical energy of the ultrasonic generator is transmitted to the ultrasonic vibrator through wires and conductive rings.

[0013] The blade rotates in the oil pipe.

[0014] The leaf spring on the outer shaft has a deformation function, and the scraper blade expands and contracts according to the thickness of the dirt on the inner wall of the casing.

[0015] A connecting device is provided at the upper end of the inner shaft for connecting the test wire.

[0016] The support structures of the upper centralizer and the lower centralizer are distributed at 120°, forming a medium flow channel.

[0017] Compared with traditional wellbore cleaning tools, the present invention adds an ultrasonic descaling device, realizing the combination of traditional mechanical descaling and ultrasonic descaling. The descaling effect is more efficient and convenient. During the operation process, the gas well does not shut down production and does not affect the gas well output. Sometimes, it is necessary to increase the gas well output, and a larger natural gas flow rate is used to carry out more blockages. The wellbore cleaning efficiency is higher, and the ultrasonic wave also has a certain plugging removal effect on the perforation compaction zone while descaling, improving the formation permeability. The structure of the present invention is simple, durable, safe and reliable, and convenient for maintenance, which is beneficial to improving the gas well opening rate, avoiding unnecessary tubing replacement and well flushing operations, protecting the gas well reservoir, and increasing the gas well output. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of an ultrasonic rotary hole opener of the present invention;

[0019] Figure markings: 1-front bearing, 2-upper stabilizing sleeve, 3-motor rotor, 4-motor stator, 5-connecting key, 6-front leaf spring bracket, 7-blade, 8-leaf spring, 9-rear bearing, 10-ultrasonic transducer vibrator, 11-positive wire, 12-connecting thread, 13-negative wire, 14-lower stabilizing sleeve, 15-inner shaft plug, 16-motor live wire, 17-motor neutral wire, 18-ultrasonic transducer, 19-ultrasonic transducer upper cover, 20-ultrasonic transducer base, 21-rotor shaft, 22-outer shaft, 23-inner shaft. DETAILED DESCRIPTION

[0020] The following are specific embodiments of the present invention, which further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0021] Example 1

[0022] The ultrasonic rotary well-clearing gauge is lowered into the gas well tubing through the test vehicle, the power is turned on, the motor and the ultrasonic generator are started, and the tubing scaling is judged by the motor current value. The current is relatively stable when the motor is running. If a blockage is encountered, the motor speed decreases, the torque increases, and the current increases accordingly. According to the current change, the tubing scaling is judged and the speed of the ultrasonic rotary well-clearing gauge is adjusted. Generally, the ultrasonic frequency is 28KHZ, and the irradiation time is 5-10min, which can clear 95% of the blockages on the inner wall of the tubing. During the use of the ultrasonic rotary well-clearing gauge and the method of use, the gas well does not stop production, and the blockage is taken out of the gas well by the flow of the gas well's own natural gas, so as to clear the scaling problem of the gas well tubing.

[0023] The invention has a compact spatial structure, substantially does not occupy ground space, is easy to place tools, and does not affect gas well production.

[0024] An ultrasonic rotary well-drilling gauge and a use method thereof comprise a motor, a rotary well-drilling gauge, an ultrasonic generator and an ultrasonic transducer.

[0025] The ultrasonic generator and the ultrasonic transducer are mature products, and they can be completed by directly purchasing and manufacturing according to the required models. The ultrasonic generator and the ultrasonic transducer are connected by wires. The ultrasonic generator is placed at the wellhead, and the ultrasonic transducer is lowered into the tubing with the device and installed at the head of the ultrasonic rotary hole opener. Ultrasonic vibrators are evenly embedded on the outer wall of the upper joint of the ultrasonic transducer. The ultrasonic transducer is used to convert electrical energy into ultrasonic waves to clean the scale on the wellbore wall. The ultrasonic transducer consists of ultrasonic vibrators, positive wires, negative wires, and wires. The electrical connector is connected to the conductive ring of the ultrasonic transducer through a power wire installed in the hole of the upper joint of the ultrasonic transducer. The conductive ring of the ultrasonic transducer is connected to the ultrasonic vibrators through wires. The current generated by the external power supply is successively transmitted to the ultrasonic vibrators through the electrical connector of the ultrasonic generator, the power wire, the positive and negative conductive rings, and the wires. The ultrasonic vibrators convert the electrical energy into ultrasonic waves of the corresponding frequency.

[0026] The composition structure of the rotary hole opener includes a rotary hole opener motor, an upper centralizer, a lower centralizer, an inner shaft (the center of the inner shaft is hollow to facilitate the passage of wires and is connected to the ultrasonic transducer through threads), an outer shaft (connected to the motor rotor shaft through a coupling key), a front bearing, a rear bearing, leaf springs, and blades. Connection method: The inner shaft sleeve of the rotary hole opener is connected to the ultrasonic transducer through threads. Bearings are installed at both ends of the inner shaft, and the outer shaft is installed on the bearings. The outer shaft is connected to the motor rotor through a coupling key. The upper centralizer is installed on the motor housing, leaf springs are installed on the outer shaft, blades are installed on the leaf springs, and the lower centralizer is installed on the inner shaft. Working method: The output electrical energy of the ultrasonic generator is transmitted to the ultrasonic vibrators through wires and conductive rings. The ultrasonic vibrators convert the electrical energy into ultrasonic waves of the required frequency. The ultrasonic waves irradiate the blockage to achieve the purpose of scale removal. Electrical energy is supplied to the motor connector to generate rotational mechanical energy, which is transmitted to the blades through the outer shaft and leaf springs. The blades rotate in the tubing to further achieve the purpose of scale removal. The leaf springs on the outer shaft have a deformation function, so that the scraping blades of the pipe scraper can expand and contract according to the thickness of the dirt on the inner wall of the casing to achieve the purpose of scraping the dirt layer by layer.

[0027] A connecting device is provided at the upper end of the inner shaft for connecting the test wire.

[0028] The support structures of the upper centralizer and the lower centralizer are distributed at 120°, forming a medium flow channel.

[0029] Research on the scale removal mechanism: The ultrasonic scale removal technology mainly relies on the cavitation effect, shear effect, and activation effect of sound waves with a frequency higher than 20 kHz to remove the dirt on the pipe wall. The following three effects are cited from "Experimental Study on Ultrasonic Removal of Barium Sulfate Scale".

[0030] Cavitation effect: The pulsed oscillation wave generated by the ultrasonic generator propagates in the pipeline, and a large number of fine cavities and bubbles will be generated at the interface between the pipeline and the fluid. The water in the fluid acts as cavitation nuclei, and the bubbles burst under the action of the ultimate pressure. At the same time, the fine particles in the fluid continuously scour the inner wall of the pipeline, further intensifying the cavitation intensity. After the bubbles obtain energy, they vibrate continuously under the action of the sound field, and the pressure formed at the interface gradually increases. When the bubbles expand rapidly, squeeze each other, and suddenly burst, on the one hand, an instantaneous high temperature is generated at the bubble interface, resulting in a decrease in the viscosity and surface tension of the liquid, a decrease in the cavitation threshold, promoting the formation of cavitation bubbles, and being more conducive to the occurrence of the cavitation effect; on the other hand, a certain range of local impact force will be generated on the surface of the scale layer, making the scale layer loose, generating fatigue and cracks, forming more dispersed small particles, and causing the scale to fall off under the scouring of the fluid or the action of mechanical force.

[0031] Shearing effect: Due to the different abilities of the scale layer and the pipeline to absorb and reflect ultrasonic waves, there is a velocity difference in the propagation of ultrasonic waves between the two, resulting in a relative shearing force at the two interfaces, reducing the adhesion force formed between the scale layer and the inner wall of the pipeline, reducing the dirt adhesion force, and making the scale layer easy to peel off. When the frequency of the ultrasonic oscillator is the same as the natural frequency of the scale layer attached to the inner wall of the pipeline, a resonance phenomenon will occur, the scale layer will become fatigued and loose, the scale will be crushed, and the scale will gradually fall off from the pipe wall. In addition, under the action of ultrasonic waves, the fluid will form fine vortices, generating a swirling effect, loosening the scale layer, and at the same time, it can also prevent the formed scale crystals from accumulating on the inner wall of the pipeline.

[0032] Activation effect: In a liquid medium, ultrasonic waves can cause water molecules to split into active H free radicals and HO free radicals, or even H+ and HO-. Active H free radicals are chemically active and have oxidizing properties. They are easy to react with scale substances and can peel off the generated deposits; while HO free radicals can form complexes such as CaOH+ and MgOH+ with scale-forming substance ions, increasing the ability of water to dissolve dirt and reducing the amount of scale attached to the inner wall of the pipeline.

Claims

1. An ultrasonic rotary hole opener, characterized in that: It includes a motor, a rotary wellbore gauge, an ultrasonic generator, and an ultrasonic transducer. The inner bushing of the rotary wellbore gauge is connected to the ultrasonic transducer by threads. Bearings are installed at both ends of the inner shaft, and an outer shaft is installed on the bearings. The outer shaft is connected to the motor rotor through a coupling key. An upper centralizer is installed on the motor housing, a leaf spring is installed on the outer shaft, a blade is installed on the leaf spring, and a lower centralizer is installed on the inner shaft.

2. The ultrasonic rotary hole opener according to claim 1, characterized in that: The ultrasonic transducer consists of an ultrasonic vibrator, a positive wire, a negative wire, and wires. The electrical connector is connected to the conductive ring of the ultrasonic transducer through a power wire installed in the connector hole of the ultrasonic transducer. The conductive ring of the ultrasonic transducer is connected to the ultrasonic vibrator through wires. The current generated by the external power supply is sequentially transmitted to the ultrasonic vibrator through the electrical connector of the ultrasonic generator, the power wire, the positive and negative conductive rings, and the wires. The ultrasonic vibrator converts electrical energy into ultrasonic waves of corresponding frequencies.

3. The ultrasonic rotary hole opener according to claim 1, characterized in that: The center of the inner shaft is hollow to facilitate the passage of wires and is connected to the ultrasonic transducer by threads.

4. The ultrasonic rotary hole opener according to claim 1, characterized in that: The outer shaft is connected to the motor rotor shaft through a coupling key.

5. The ultrasonic rotary hole opener according to claim 1, wherein: The output electrical energy of the ultrasonic generator is transmitted to the ultrasonic vibrator through wires and conductive rings.

6. The ultrasonic rotary hole opener according to claim 1, wherein: The blade rotates inside the oil pipe.

7. The ultrasonic rotary hole opener according to claim 1, wherein: The leaf spring on the outer shaft has a deformation function, and the scraping blade of the pipe scraper expands and contracts according to the thickness of the dirt on the inner wall of the casing.

8. An ultrasonic rotary hole opener according to claim 1, characterized in that: A connecting device is provided at the upper end of the inner shaft for connecting the test wire.

9. The ultrasonic rotary hole opener according to claim 1, characterized in that: The support structures of the upper centralizer and the lower centralizer are distributed at 120°, forming a medium flow channel.

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