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CN105804724B - Ultrasonic liquid level monitoring device for petroleum drilling - Google Patents

Ultrasonic liquid level monitoring device for petroleum drilling Download PDF

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Publication number
CN105804724B
CN105804724B CN201410837099.0A CN201410837099A CN105804724B CN 105804724 B CN105804724 B CN 105804724B CN 201410837099 A CN201410837099 A CN 201410837099A CN 105804724 B CN105804724 B CN 105804724B
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ultrasonic
liquid level
trigger
data acquisition
sensors
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CN105804724A (en
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陈东时
贺小桥
何建辉
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00Technologies having an indirect contribution to adaptation to climate change
    • Y02A90/30Assessment of water resources

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Abstract

The invention discloses an ultrasonic liquid level monitoring device for petroleum drilling, and relates to the technical field of liquid level detection equipment for petroleum drilling; the ground control device comprises a power supply, a data acquisition unit, a controller, a display and a trigger, wherein the data acquisition unit, the trigger and the display are electrically connected with the controller; the ultrasonic liquid level detector comprises a plurality of groups of ultrasonic transmitting sensors and ultrasonic receiving sensors, wherein the ultrasonic transmitting sensors and the ultrasonic receiving sensors are connected to the data acquisition unit, the trigger is electrically connected to the data acquisition unit, and the trigger is also connected to the ultrasonic transmitting sensors and the ultrasonic receiving sensors; the beneficial effects of the invention are as follows: according to the invention, through different received signals, the gas or slurry medium is judged from different time parameters and different voltage pulse signal states, so that operators on the ground can be guided to perform corresponding operations.

Description

Ultrasonic liquid level monitoring device for petroleum drilling
Technical Field
The invention relates to liquid level monitoring equipment for petroleum and natural gas drilling, in particular to an ultrasonic liquid level monitoring device for petroleum drilling.
Background
In oil and gas exploration and exploitation drilling, drilling mud is used for cooling a drill bit, implementing jet drilling and taking rock cut by the drill bit at the bottom of the well from the bottom of the well to the ground, and in addition, the density of the drilling mud can be adjusted to balance the mud liquid column of the annulus of the well with the pressure in the well, so that possible blowout accidents can be prevented by the balance. During the tripping process, when the drilling tool is lifted, the liquid level of the shaft is lowered, the lowering height of the liquid level is proportional to the number (length) of the tripping drill rods, and the volume of the drilling mud to be supplemented is also equivalent to the volume of the tripping drill rods, and the drilling mud is injected into the shaft through the mud injection device.
The conventional drilling mud filling device comprises a main controller, a mud tank with a stirrer, a liquid level monitor of the mud tank, a filling mechanism comprising a mud pump, a motor, an electric cabinet and a flow sensor, and an overflow return mechanism. The method for pouring is that the number of drill rods is calculated manually during the process of starting the drill, then the drill rods are input into a host machine for processing, a pouring instruction and the volume of mud to be poured into are sent to a pouring mechanism, the pouring instruction and the volume of mud to be poured into are executed and metered through a mud pump and a flow sensor arranged at the pump port, and meanwhile, information is fed back to the host machine to control the pouring amount of the drill rods.
Normally, the slurry flowing out of the slurry pond and the slurry flowing in are balanced. If an imbalance occurs, this will mean that a blow out or lost circulation will occur. When the liquid level of the slurry in the shaft is reduced, the slurry is accurately poured in time, so that the depth change of the underground drilling liquid level is necessary to be monitored in real time.
In most cases, the liquid level monitoring under the petroleum well is carried out by judging and identifying the liquid level according to manual experience, and the liquid level cannot be monitored in real time, so that the method is neither scientific nor exact.
The liquid level of the mud pit is measured, a float type liquid level detector and a scale with scales are generally adopted in the prior art, a driller is required to manually observe, record and compare, and then whether overflow or lost circulation occurs is judged. Thus, under normal conditions, the amount of mud pumped downhole from the mud tank should be substantially equal to the amount of mud returned downhole, but when lost circulation is encountered, the mud returned downhole is lost little or completely, and the mud level in the mud tank is rapidly lowered; or when the well kick is generated due to the sudden high pressure in the well, the upward pressure in the well pushes the slurry in the well annulus to kick upwards and enter the slurry tank, and the slurry level in the slurry tank can rise rapidly; when the two conditions occur, if the plugging of the grouting slurry or the implementation of well killing by the weighting slurry cannot be found and adopted in time, serious accidents are caused. In order to know the height of the liquid level in the mud tank in time, the basic method at present is to arrange personnel to detect the liquid level in the mud tank at any time when the liquid level reaches a preset level, a liquid level display is arranged on the mud tank, the other end of the display is connected with a floater through a soft rope, when the liquid level is at a set height, the floater is just floated, the reading on the display is at the set position, and when the liquid level is lowered or exceeds the set height, the display is pulled by the floater to downwards or upwards display dangerous liquid level; and the liquid level is tested by adopting sound waves or light, and an alarm is given when the upper limit and the lower limit of the liquid level are exceeded. The problems of these devices are that the former is connected by a soft rope, so that the measured liquid level is inaccurate and false alarm sometimes occurs; the latter, although using modern technology, all devices are electronic products which are easily damaged when used in the harsh environment of the drilling site, especially when the mud tank is cleaned, the electronic products are inevitably damaged, and the maintenance cost is also very expensive, and the maintenance must be completed by a professional technician.
In addition, the slurry tank has large volume, and after the well kick or the well leakage occurs, the liquid level of the slurry tank changes slowly, so that the well kick and the well leakage accident can not be monitored sensitively. Thus, a system for rapid, sensitive monitoring of mud is needed.
For the slurry liquid level in a shaft, no mature and reliable technology is used for accurately and real-time monitoring at present, the underground liquid level detection cannot be directly carried out by utilizing the ultrasonic principle, and non-contact application cannot be realized. Liquid media have also been studied abroad using ultrasound. However, even short-range transmission of ultrasonic signals is very difficult due to the scattering and absorption properties of drilling fluids (muds), especially oil-based muds, for ultrasonic waves.
Disclosure of Invention
The invention aims to effectively overcome the defects of the technology, and provides an ultrasonic liquid level monitoring device for petroleum drilling, which is used for monitoring the liquid level in a shaft in real time by utilizing the characteristics of ultrasonic waves with different propagation speeds under different media and different penetration characteristics of gas, liquid and solid media.
The technical scheme of the invention is realized as follows: the device comprises a ground control device and an ultrasonic liquid level detector, and the principle and the implementation scheme are as follows:
the ground control device comprises a power supply, a data acquisition unit, a controller, a display and a trigger, wherein the data acquisition unit, the trigger and the display are electrically connected with the controller;
the ultrasonic liquid level detector comprises a plurality of groups of ultrasonic emission sensors and ultrasonic receiving sensors, wherein the ultrasonic emission sensors and the ultrasonic receiving sensors are connected to the data acquisition device, the trigger is electrically connected to the data acquisition device, and the trigger is further connected to the ultrasonic emission sensors and the ultrasonic receiving sensors. The ultrasonic liquid level detector is driven by the inner sleeve to the well, and the drilling depth is the depth of the liquid level (or gas) at the detection point which is required to be monitored, thus the ultrasonic liquid level detector is used for detecting
And (5) monitoring the drilling liquid level in real time.
The power supply is electrically connected with the data acquisition device, the trigger, the ultrasonic transmitting sensor and the ultrasonic receiving sensor and used for providing required electric energy.
Preferably, the upper end of the ultrasonic liquid level detector is connected to the inner sleeve, the lower end of the ultrasonic liquid level detector is connected to the coupling, and the lower end of the coupling is connected with the other inner sleeve.
Preferably, the ultrasonic liquid level detector further comprises a supporting seat sleeve and an ultrasonic transmitting and receiving integrated circuit board, the ultrasonic transmitting sensor and the ultrasonic receiving sensor are oppositely arranged on two sides of the supporting seat sleeve, the supporting seat sleeve is provided with a special-shaped groove communicated with the inner sleeve, and the ultrasonic transmitting sensor and the ultrasonic receiving sensor are electrically connected to the ultrasonic transmitting and receiving integrated circuit board.
In the structure, the ultrasonic liquid level detector is connected with a steel pipe cable, and the other end of the steel pipe cable is connected to a power supply and a data collector.
In the structure, the outer surface of the inner sleeve is provided with the cable clamp and the cable protector, the cable clamp is used for fastening the steel pipe cable, and the cable protector protects the cable.
In the above structure, the ultrasonic liquid level detector further comprises a standby ultrasonic transmitting sensor and a standby ultrasonic receiving sensor.
The invention has the beneficial effects that: the invention relates to an ultrasonic liquid level monitoring device for petroleum drilling, which is used for monitoring the liquid level of petroleum underground drilling liquid (commonly called slurry) by utilizing the characteristic that ultrasonic waves have different propagation speeds under different media and the different penetration characteristics of gas, liquid and solid media, and the ultrasonic liquid level monitoring device is connected with an inner sleeve of petroleum in a threaded manner, so that an ultrasonic liquid level detector is lowered to the well depth to be monitored, an ultrasonic transmitting sensor in the device is triggered by a ground control signal to send out an ultrasonic signal, and an ultrasonic receiving sensor with the same frequency is arranged at the other side of the device to receive a corresponding ultrasonic signal; the gas or slurry medium is judged to be underground at the bottom of the depth through the received different signals according to the difference of time parameters and the state of the voltage pulse signals, so that operators on the ground can be guided to perform corresponding operations; according to factors such as design well depth and casing, two groups of ultrasonic sensors are respectively arranged at ten to fifty meters and two to five hundred meters below the ground, when the positions of the upper group of ultrasonic sensors and the lower group of ultrasonic sensors are detected to be gas in the casing in the process of tripping, mud is poured into the tubular column, and when the pouring time exceeds a certain time, the upper ultrasonic sensor still cannot detect the mud in the casing, so that well leakage is indicated, and the alarm and the leakage blocking can be timely carried out; stopping pouring when the upper ultrasonic sensor detects mud in the sleeve; the whole process realizes automatic control by means of a computer.
[ description of the drawings ]
FIG. 1 is a schematic block diagram of the present invention;
FIG. 2 is a diagram of an embodiment of the present invention;
fig. 3 is a schematic diagram of the present invention.
[ detailed description ] of the invention
The invention is further described below with reference to the drawings and examples.
Referring to FIG. 1, the ultrasonic liquid level monitoring device for petroleum drilling disclosed by the invention is used for judging whether a specific depth of a well is gas or slurry medium, so that operators on the ground can be guided to perform corresponding operations.
Specifically, referring to fig. 1 to 3, the ultrasonic liquid level detection device for petroleum drilling of the present invention includes a ground control device and an ultrasonic liquid level detector, wherein the ground control device includes a power supply 10, a data collector 20, a controller 30, a display 40 and a trigger 50, and the data collector 20, the trigger 50 and the display 40 are all electrically connected with the controller 30; the ultrasonic liquid level detector 90 comprises a plurality of groups of ultrasonic transmitting sensors 60 and ultrasonic receiving sensors 70, the ultrasonic transmitting sensors 60 and the ultrasonic receiving sensors 70 are connected to the data collector 20, the trigger 50 is electrically connected to the data collector 20, the trigger 50 is also connected to the ultrasonic transmitting sensors 60 and the ultrasonic receiving sensors 70, a steel pipe cable 901 is connected to the ultrasonic liquid level detector 90, and the other end of the steel pipe cable 901 is connected to the power supply 10 and the data collector 20, as shown in fig. 2. The power supply 10 is electrically connected with the data collector 20, the trigger 50, the ultrasonic transmitting sensor 60 and the ultrasonic receiving sensor 70, and is used for providing the required electric energy. The ultrasonic liquid level detector 90 further includes a standby ultrasonic transmitting sensor and a standby ultrasonic receiving sensor.
Referring to fig. 2, in this embodiment, the upper end of the ultrasonic liquid level detector 90 is connected to the inner sleeve 902, the lower end of the ultrasonic liquid level detector is connected to the coupling 903, and the lower end of the coupling 903 is connected to another inner sleeve 902, so that a plurality of ultrasonic liquid level detectors 90 are connected. The ultrasonic liquid level detector 90 further comprises a supporting seat sleeve and an ultrasonic transmitting and receiving integrated circuit board (not labeled in the figure), the ultrasonic transmitting sensor 60 and the ultrasonic receiving sensor 70 are oppositely arranged on two sides of the supporting seat sleeve, the supporting seat sleeve is provided with a special-shaped groove communicated with the inner sleeve, and the ultrasonic transmitting sensor 60 and the ultrasonic receiving sensor 70 are electrically connected to the ultrasonic transmitting and receiving integrated circuit board; a cable clip 904 and a cable protector 905 are mounted on the outer surface of the inner sleeve 902, the cable clip 904 being used to secure the steel tube cable 901 described above, the cable protector 905 protecting the cable.
The operation and principle of the ultrasonic liquid level monitoring device for petroleum drilling according to the present invention will be described in detail with reference to fig. 3, according to the snell's law of sound waves: when an ultrasonic wave is obliquely incident on an interface, the following relationship exists among the angles of a reflected wave, a refracted wave and an incident wave (law of reflection and refraction): sin alpha/C 1 =sinβ/C 2 . Where α is the angle of incidence of the first medium and β is the angle of refraction of the second medium. C (C) 1 For the propagation rate of the first medium, C 2 Is the propagation rate of the second medium.
From the principle of downhole ultrasonic level detection in FIG. 3, we can determine the angle of incidence α, and C of the ultrasonic emission 1 The transverse wave propagation rate of ultrasonic waves in the metal sleeve material is set; c (C) 2 Is the propagation velocity of ultrasonic waves in the mud (or air). The parameters can be determined, so that the beta value, namely the refraction angle of the ultrasonic waves entering the slurry (or air) medium after being refracted by the steel casing, can be calculated.
The path 1 from the ultrasonic transmitting sensor to the ultrasonic receiving sensor 1 is the transmission condition of the mud ultrasonic wave without a drill rod in the sleeve.
The path 2 from the ultrasonic transmitting sensor to the ultrasonic receiving sensor 2 is the case that the drill rod in the casing has mud.
When no mud is present in the casing, neither the ultrasonic receiving sensor 1 nor the receiving sensor 2 receives a signal due to the rapid attenuation of high frequency ultrasonic waves in the air.
By utilizing the characteristics of ultrasonic waves with different propagation speeds under different media and different penetration characteristics of gas, liquid and solid media, the underground petroleum drilling fluid and air media can be judged, so that whether a specific monitoring point is a mud liquid level or an air media is judged, and the purpose of liquid level monitoring is achieved. According to the invention, through different received signals, the gas or slurry medium is judged from different time parameters and different voltage pulse signal states, so that operators on the ground can be guided to perform corresponding operations.
The foregoing description is only of the preferred embodiments of the invention, and the above-described embodiments are not intended to limit the invention. Various changes and modifications may be made within the scope of the technical idea of the present invention, and any person skilled in the art may make any modification, modification or equivalent substitution according to the above description, which falls within the scope of the present invention.

Claims (3)

1. The utility model provides an oil drilling ultrasonic wave liquid level monitoring device, it includes ground controlling means and ultrasonic wave liquid level detector, its characterized in that: the ground control device comprises a power supply, a data acquisition unit, a controller, a display and a trigger, wherein the data acquisition unit, the trigger and the display are electrically connected with the controller;
the ultrasonic liquid level detector comprises a plurality of groups of ultrasonic transmitting sensors and ultrasonic receiving sensors, wherein the ultrasonic transmitting sensors and the ultrasonic receiving sensors are connected to the data acquisition unit, the trigger is electrically connected to the data acquisition unit, and the trigger is also connected to the ultrasonic transmitting sensors and the ultrasonic receiving sensors;
the power supply is electrically connected with the data acquisition device, the trigger, the ultrasonic transmitting sensor and the ultrasonic receiving sensor and used for providing required electric energy;
the upper end of the ultrasonic liquid level detector is connected to the inner sleeve, the lower end of the ultrasonic liquid level detector is connected to the coupling, and the lower end of the coupling is connected with the other inner sleeve; the ultrasonic liquid level detector also comprises a supporting seat sleeve and an ultrasonic transmitting and receiving integrated circuit board, wherein the ultrasonic transmitting sensor and the ultrasonic receiving sensor are oppositely arranged on two sides of the supporting seat sleeve, the supporting seat sleeve is provided with a special-shaped groove communicated with the inner sleeve, and the ultrasonic transmitting sensor and the ultrasonic receiving sensor are electrically connected to the ultrasonic transmitting and receiving integrated circuit board;
the ultrasonic liquid level detector is connected with a steel pipe cable, and the other end of the steel pipe cable is connected to a power supply and a data acquisition device.
2. The ultrasonic liquid level monitoring device for petroleum drilling according to claim 1, wherein: the outer surface of the inner sleeve is provided with a cable clamp and a cable protector, the cable clamp is used for fastening the steel pipe cable, and the cable protector protects the cable.
3. The ultrasonic liquid level monitoring device for petroleum drilling according to claim 1, wherein: the ultrasonic liquid level detector also comprises a standby ultrasonic transmitting sensor and a standby ultrasonic receiving sensor.
CN201410837099.0A 2014-12-29 2014-12-29 Ultrasonic liquid level monitoring device for petroleum drilling Active CN105804724B (en)

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Publication number Priority date Publication date Assignee Title
CN107340033B (en) * 2017-07-19 2023-05-12 中国科学院西北生态环境资源研究院 Frozen soil area heat pipe working medium liquid level detection device based on sound wave reflection
CN108430025B (en) * 2018-03-07 2020-06-19 维沃移动通信有限公司 Detection method and mobile terminal
CN108487901A (en) * 2018-05-23 2018-09-04 大庆市亿动科技有限公司 Oil well multi-functional automatic liquid level monitor based on velocity of sound sensor
CN111577249B (en) * 2020-04-28 2023-05-30 中国石油大学(华东) Multi-sensor layout underground drill string operation attitude measuring instrument
CN113586033B (en) * 2021-08-05 2023-09-26 思凡(上海)石油设备有限公司 Gas detection device for logging

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1292088A (en) * 1998-01-06 2001-04-18 施卢默格海外有限公司 Method and apparatus for ultrasonic imaging of cased well
CN2760228Y (en) * 2004-08-20 2006-02-22 西安石油大学 A leak hunting apparatus for drilling fluid
CN103063274A (en) * 2012-12-25 2013-04-24 天津大学 Piezoelectric transducer downhole liquid level measuring instrument
CN103776499A (en) * 2014-02-07 2014-05-07 中国科学院南海海洋研究所 In-situ ultrasonic measurement system for seepage flow of seafloor cold spring natural gas
CN204591261U (en) * 2014-12-29 2015-08-26 何建辉 A kind of oil drilling ultrasonic liquid level monitoring device

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE319914T1 (en) * 2002-12-31 2006-03-15 Schlumberger Services Petrol DEVICE AND METHOD FOR MEASURING ULTRASONIC VELOCITY IN DRILLING FLUID

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1292088A (en) * 1998-01-06 2001-04-18 施卢默格海外有限公司 Method and apparatus for ultrasonic imaging of cased well
CN2760228Y (en) * 2004-08-20 2006-02-22 西安石油大学 A leak hunting apparatus for drilling fluid
CN103063274A (en) * 2012-12-25 2013-04-24 天津大学 Piezoelectric transducer downhole liquid level measuring instrument
CN103776499A (en) * 2014-02-07 2014-05-07 中国科学院南海海洋研究所 In-situ ultrasonic measurement system for seepage flow of seafloor cold spring natural gas
CN204591261U (en) * 2014-12-29 2015-08-26 何建辉 A kind of oil drilling ultrasonic liquid level monitoring device

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