CN102877839B - Acoustic transducer and logging device thereof - Google Patents
Acoustic transducer and logging device thereof Download PDFInfo
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- CN102877839B CN102877839B CN201210382225.9A CN201210382225A CN102877839B CN 102877839 B CN102877839 B CN 102877839B CN 201210382225 A CN201210382225 A CN 201210382225A CN 102877839 B CN102877839 B CN 102877839B
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Abstract
An embodiment of the invention relates to the acoustic logging field, in particular to an acoustic transducer and a logging device thereof. The acoustic transducer comprises a metal substrate and a piezoelectric ceramic piece, wherein one side of the piezoelectric ceramic piece is fixed on a first surface of the metal substrate, and a second surface of the metal substrate is directly contacted with fluids in a well. Accordingly, a sound permeable structure can be not needed, signal attenuation caused by various media during acoustic signal transmission can be reduced; and simultaneously, good acoustic emission efficiency or good acoustic signal receiving sensitivity is provided, and acoustic logging operation can be completed directly and effectively.
Description
Technical field
The present invention relates to acoustic logging field, particularly relate to a kind of acoustic wave transducer and well logging apparatus thereof.
Background technology
Acoustic logging plays more and more important effect in fields such as formation evaluation, petroleum works, petroleum production engineerings, adopt acoustic logging can obtain the multiple formation evaluation parameter such as anisotropy on the degree of porosity on stratum, permeability, the energy attenuation of ripple, reflection and transmission, stratum, apply extremely extensive.
The acoustic wave transducer of tradition well logging, all need to be sealed in field instrumentation, such as, in pressure-bearing sonic system pipe nipple, in order to make fluid isolation in the piezoelectric ceramic piece of acoustic wave transducer and well, need encapsulant (as temperature resistant rubber), metal shell etc. are from inside to outside installed successively, in this sonic system pipe nipple, acoustic signals is propagated and through multilayer dielectricity, need be certainly existed comparatively high attenuation.
In order to reduce the impact that above-mentioned metal shell is propagated acoustic signals, need in acoustic logging sonic system to design special entrant sound structure.In existing wireline logging, the entrant sound method of acoustic wave transducer generally adopts cutting sound window on shell, and the area requirements of sound window is large as far as possible with the entrant sound effect obtained.
But in well logging during, between drill collar and borehole wall stratum, there is larger friction for a long time, make the entrant sound structure of this employing large area sound window be difficult to use, thus, be also difficult to be applied in acoustic logging while drilling.
Therefore, one neither needs entrant sound structure, the signal attenuation that when acoustic signals is propagated, various medium causes can be reduced again, the acoustic wave transducer of the acoustic emission efficiency (transmitting transducer) simultaneously also had or good acoustic signals receiving sensitivity (receiving transducer) is acoustic logging while drilling field, and even the key technology in whole acoustic logging field.
Summary of the invention
The embodiment of the present invention provides a kind of acoustic wave transducer and well logging apparatus thereof, needs to arrange entrant sound structure for solving existing acoustical well-logging devices, the problem significantly decayed when therefore acoustic signals is propagated.
A kind of acoustic wave transducer that the embodiment of the present invention provides and well logging apparatus thereof, solved the problems of the technologies described above by following scheme.
A kind of acoustic wave transducer, wherein, described acoustic wave transducer comprises:
Metal substrate, piezoelectric ceramic piece; Wherein:
The one side of described piezoelectric ceramic piece is fixed on the first surface of described metal substrate, and the second surface of described metal substrate directly contacts with liquid in well.
According to above-mentioned acoustic wave transducer, wherein, described acoustic wave transducer also comprises: fixing hole, and described fixing hole is arranged on the described metal substrate of described piezoelectric ceramic piece periphery.
According to above-mentioned acoustic wave transducer, wherein, described acoustic wave transducer also comprises: annular groove, and described annular groove to be arranged on described metal substrate and around the periphery of described piezoelectric ceramic piece.
According to above-mentioned acoustic wave transducer, wherein, described annular groove is quadrangle, and wherein the degree of depth of at least one two ends, limit groove is not equal to the degree of depth of this limit mid portion groove.
According to above-mentioned acoustic wave transducer, wherein, described acoustic wave transducer has piezoelectric ceramic piece described in multi-disc, and wherein, the one side of piezoelectric ceramic piece described in each is all fixed on the first surface of described metal substrate.
According to above-mentioned acoustic wave transducer, wherein, piezoelectric ceramic piece described in two panels is comprised; Wherein, the one side of piezoelectric ceramic piece described in a slice is fixed on described metal substrate with contrary polarised direction with the one side of piezoelectric ceramic piece described in another sheet.
According to above-mentioned acoustic wave transducer, wherein, described acoustic wave transducer is tabular or arc surfaced.
The embodiment of the present invention also provides a kind of well logging apparatus, and wherein, described device comprises:
Acoustic wave transducer group and sonic system pipe nipple;
Described acoustic wave transducer group comprises: at least one is any acoustic wave transducer foregoing;
The lateral surface of described sonic system pipe nipple has a containing groove, the metal substrate of described acoustic wave transducer group covers and is fixed on described containing groove, and jointly forming a confined space with described containing groove, the piezoelectric ceramic piece of described acoustic wave transducer group is in described containing groove.
According to above-mentioned well logging apparatus, wherein, described acoustic wave transducer group is connected with described sonic system pipe nipple by fixing hole.
According to above-mentioned well logging apparatus, wherein, described device also comprises: sealing ring, is arranged between described metal substrate with the position that described sonic system pipe nipple is combined.
The acoustic wave transducer of the embodiment of the present invention as above and well logging apparatus thereof can reach following effect:
Acoustic wave transducer provided by the invention can solve Signal transmissions in traditional acoustic well logging and there is the problem compared with high attenuation through multilayer dielectricity, this transducer entrant sound structure of not needing additional traditional acoustic to log well simultaneously, the sonic system of acoustic logging instrument can be designed accordingly, be particularly useful for acoustic logging while drilling sonic system.Its metal substrate of acoustic wave transducer provided by the invention has sealing and the effect of protective cover sheet, liquid comes into contact in direct and well.During as transmitting transducer, can by liquid in well directly to radiative acoustic wave energy in borehole wall stratum, Enhanced Radiation Reduced Blast is to the effective energy on borehole wall stratum; During as receiving transducer, directly can receive the acoustic signals from borehole wall stratum, there is higher sensitivity.
Accompanying drawing explanation
Accompanying drawing described herein is used to provide a further understanding of the present invention, forms a application's part, does not form limitation of the invention.In the accompanying drawings:
Fig. 1 is the structural representation of a kind of acoustic wave transducer in the embodiment of the present invention;
Fig. 2 be in Fig. 1 of the present invention a kind of acoustic wave transducer along the generalized section in A-A direction;
Fig. 3 is the generalized section of a kind of acoustic wave transducer in another embodiment of the present invention;
Fig. 4 is the generalized section with difference connector of a kind of acoustic wave transducer in another embodiment of the present invention.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearly understand, below in conjunction with accompanying drawing, the embodiment of the present invention is described in further detail.At this, schematic description and description of the present invention is for explaining the present invention, but not as a limitation of the invention.
As shown in Figures 1 and 2, be a kind of in embodiment of the present invention structural representation and its generalized section along A-A direction of acoustic wave transducer 10, it comprises: metal substrate 101, piezoelectric ceramic piece 102; Wherein: the one side of described piezoelectric ceramic piece 102 is fixed on the first surface of described metal substrate 101, the second surface of described metal substrate 101 directly can contact with liquid in well.Preferably, the one side of piezoelectric ceramic piece 102 is bonded on the first surface of metal substrate 101.The metal substrate of the acoustic wave transducer that the embodiment of the present invention provides is one of terminal of signal I/O, in use directly the one side without piezoelectric ceramic piece outwards can be fixed on a sonic system pipe nipple, and without the need to increasing extra entrant sound structure; And adopt the acoustic wave transducer of the embodiment of the present invention both to can be used as transmitting transducer, directly the energy that vibrations produce being passed through fluid radiation in well, again can as the stratum acoustic signals of fluid coupling in receiving transducer received well in stratum.
In one provided by the present invention preferably embodiment, described acoustic wave transducer 10 also comprises annular groove 104, and described annular groove 104 to be arranged on described metal substrate 101 and around the periphery of described piezoelectric ceramic piece 102.In embodiments of the present invention by the metal substrate around piezoelectric ceramic piece is processed with annular groove, the vibration of transducer effectively can be utilized.
The acoustic wave transducer provided by the embodiment of the present invention can be made up of metal substrate and the piezoelectric ceramic piece be only fixed on one of them face of metal substrate, and metal substrate another side can directly contact with liquid in well, thus be used in acoustical well-logging devices and do not need additional any entrant sound structure, just can realize good entrant sound effect, reduce the comparatively high attenuation that Acoustic Wave Propagation in traditional acoustic well logging apparatus causes through multilayer dielectricity simultaneously.Enable transmitting transducer by liquid in well directly to radiative acoustic wave energy in borehole wall stratum, Enhanced Radiation Reduced Blast is to the effective energy on borehole wall stratum; Receiving transducer directly can receive the acoustic signals from borehole wall stratum, has higher sensitivity.And this metal substrate is not only as one of the terminal of I/O; sealing and protective effect can also be had as cover plate to the piezoelectric ceramic piece in sonic system pipe nipple, wireline logging and the well logging during needs to working environments such as ripple logger requirement shell are withstand voltage, wear-resisting can be suitable for.
According to provided by the invention one preferably embodiment; described acoustic wave transducer also comprises: fixing hole 103; described fixing hole 103 is arranged on the described metal substrate 101 of described piezoelectric ceramic piece 102 periphery; the setting of fixing hole is fixed on sonic system pipe nipple by this transducer; not only be fixed firmly to by this transducer on this sonic system pipe nipple, compound rubber sealing ring also helps protection piezoelectric ceramic piece not by the liquid in well simultaneously.
A kind of acoustic wave transducer provided by the invention, another is preferably in embodiment, due to annular groove, the vibration that effectively can utilize acoustic wave transducer is set, in order to better utilize transducer vibrations, this annular groove can be designed as different structures, preferably, described annular groove can be set to quadrangle, wherein the degree of depth of at least one two ends, limit groove is not equal to the degree of depth of (being greater than or less than) this limit mid portion (parts beyond two ends) groove, in other words, also can be the depth of groove that the degree of depth of the groove mid portion at least one limit is greater than or less than point of intersection between limit and limit, whereby, the Oscillation Amplitude of this acoustic wave transducer can be improved, produce effective vibration mode, avoid the therefore acoustic attenuation produced.The concrete degree of depth can be determined according to the vibration mode of transducer and to the demand of acoustic wave transducer.
A kind of acoustic wave transducer provided by the invention, another is preferably in embodiment, and as shown in Figure 3, described acoustic wave transducer has piezoelectric ceramic piece 102 described in multi-disc, wherein, described in each, the one side of piezoelectric ceramic piece 102 is all fixed on the first surface of described metal substrate.By two panels and above multi-disc piezoelectric ceramic piece, the metal substrate wherein around every a slice piezoelectric ceramic piece all can be provided with annular groove, and the similar of the acoustic wave transducer that itself and monolithic piezoelectric ceramic sheet are formed, therefore repeats no more.For transmitting transducer, adopt the piezoelectric ceramic piece of biplate or multi-disc can improve the acoustic wave energy being radiated stratum.
A kind of acoustic wave transducer provided by the invention, another is preferably in embodiment, described transducer comprises piezoelectric ceramic piece described in two panels, the one side of piezoelectric ceramic piece described in a slice is fixed on described metal substrate with the one side of piezoelectric ceramic piece described in another sheet with contrary polarised direction, as shown in Figure 4, the negative pole of one piezoelectric ceramic piece 102 is adhered on metal substrate 101, and the positive pole of another piezoelectric ceramic piece 102 ' is bonded on metal substrate 101, such piezoelectric ceramic piece 102 and 102 ' is contrary with the polarised direction of metal substrate bonding plane, and above-mentioned two panels piezoelectric ceramic piece 102 and 102 ' another side respectively can connect a lead-out terminal, in order to output difference sub-signal, sensitivity and the antijamming capability of transducer can be improved like this, be especially suitable for use as receiving transducer.
A kind of acoustic wave transducer provided by the invention, another is preferably in embodiment, and described acoustic wave transducer is tabular or arc surfaced, can appropriate cable well logging and well logging during to the requirement of transducer profile.
Also provide a kind of well logging apparatus in embodiment of the present invention, this device comprises: acoustic wave transducer group and sonic system pipe nipple;
Described acoustic wave transducer group comprises: at least one any acoustic wave transducer as described in above-described embodiment; This acoustic wave transducer can be used as transmitting transducer, also can be used as receiving transducer, or comprises transmitting transducer and receiving transducer in acoustic wave transducer group simultaneously.Preferably, when comprising transmitting transducer and receiving transducer at the same time, a sound arrester is set usually, avoids sound wave directly to propagate into receiving transducer from transmitting transducer by the shell of sonic system pipe nipple.Preferably described acoustic wave transducer can be tabular or arc surfaced according to wireline logging and well logging during to the requirement of the profile of acoustic wave transducer.
One embodiment of the present of invention, can be used in the operation of acoustic logging while drilling, wherein, the lateral surface of described sonic system pipe nipple has a containing groove, the metal substrate of described acoustic wave transducer group covers and is fixed on described containing groove, and jointly forming a confined space with described containing groove, the piezoelectric ceramic piece of described acoustic wave transducer group is in described containing groove, and the second surface of described metal substrate directly contacts with liquid in well.Metal substrate liquid comes into contact directly and in well; and piezoelectric ceramic piece is in the sonic system pipe nipple of sealing; like this without the need to the topping of additional entrant sound structure and outer layer covers; the decay that when acoustic signals is propagated, various medium causes can be reduced, the acoustic emission efficiency (transmitting transducer) simultaneously had or good receiving sensitivity (receiving transducer).Metal substrate is wherein not only as one of the terminal of I/O; sealing and protective effect can also be had as cover plate to the piezoelectric ceramic piece in sonic system pipe nipple, the needs of well logging during to working environments such as ripple logger requirement shell are withstand voltage, wear-resisting can be adapted to.
A kind of well logging apparatus provided by the invention, wherein a preferably embodiment, described acoustic wave transducer group is connected with described sonic system pipe nipple by fixing hole.The setting of fixing hole is fixed in the groove on sonic system pipe nipple by this transducer, is beneficial to protect piezoelectric ceramic piece not by the liquid in well.
A kind of well logging apparatus provided by the invention, another is preferably in embodiment, described device also comprises: sealing ring, be arranged between described metal substrate with the position that described sonic system pipe nipple is combined, what can make metal substrate and sonic system pipe nipple like this engages tightr, ensure airtight to sonic system pipe nipple transducer placement space, prevent extraneous medium from flowing into transducer placement space in sonic system pipe nipple inner and affect piezoelectric ceramic piece.
Whereby, a kind of acoustic wave transducer that the embodiment of the present invention provides and well logging apparatus not only simple and reasonable, and save the setting of entrant sound structure and various encapsulant, not only reduce cost and the manufacturing cost of material, make the decay of acoustic signals when propagating greatly reduce simultaneously, and the acoustic emission efficiency (transmitting transducer) had or good receiving sensitivity (receiving transducer), be particularly suitable for acoustic logging while drilling field.
Above-described detailed description of the invention; object of the present invention, technical scheme and beneficial effect are further described; be understood that; the foregoing is only the specific embodiment of the present invention; the protection domain be not intended to limit the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (7)
1. an acoustic wave transducer, is characterized in that, described acoustic wave transducer comprises:
Metal substrate, piezoelectric ceramic piece; Wherein:
Described acoustic wave transducer has piezoelectric ceramic piece described in multi-disc, and wherein, the one side of piezoelectric ceramic piece described in each is all fixed on the first surface of described metal substrate, and the second surface of described metal substrate directly contacts with liquid in well;
Also comprise: annular groove, described annular groove to be arranged on described metal substrate and around the periphery of described piezoelectric ceramic piece;
Wherein, described acoustic wave transducer comprises piezoelectric ceramic piece described in two panels; Wherein, the one side of piezoelectric ceramic piece described in a slice is fixed on described metal substrate with contrary polarised direction with the one side of piezoelectric ceramic piece described in another sheet.
2. acoustic wave transducer according to claim 1, is characterized in that, described acoustic wave transducer also comprises: fixing hole, and described fixing hole is arranged on the described metal substrate of described piezoelectric ceramic piece periphery.
3. acoustic wave transducer according to claim 1, is characterized in that, described annular groove is quadrangle, and wherein the degree of depth of at least one two ends, limit groove is not equal to the degree of depth of this limit mid portion groove.
4. acoustic wave transducer according to claim 1, is characterized in that, described acoustic wave transducer is tabular or arc surfaced.
5. a well logging apparatus, is characterized in that, described device comprises:
Acoustic wave transducer group and sonic system pipe nipple;
Described acoustic wave transducer group comprises: at least one any acoustic wave transducer as described in Claims 1 to 4;
The lateral surface of described sonic system pipe nipple has a containing groove, the metal substrate of described acoustic wave transducer group covers and is fixed on described containing groove, and jointly forming a confined space with described containing groove, the piezoelectric ceramic piece of described acoustic wave transducer group is in described containing groove.
6. well logging apparatus according to claim 5, is characterized in that, described acoustic wave transducer group is connected with described sonic system pipe nipple by fixing hole.
7. well logging apparatus according to claim 6, is characterized in that, described device also comprises: sealing ring, is arranged between described metal substrate with the position that described sonic system pipe nipple is combined.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201210382225.9A CN102877839B (en) | 2012-10-10 | 2012-10-10 | Acoustic transducer and logging device thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210382225.9A CN102877839B (en) | 2012-10-10 | 2012-10-10 | Acoustic transducer and logging device thereof |
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| CN102877839A CN102877839A (en) | 2013-01-16 |
| CN102877839B true CN102877839B (en) | 2015-05-20 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| DE112013007551T5 (en) * | 2013-10-31 | 2016-07-21 | Halliburton Energy Services, Inc. | Acoustic signal attenuator for LWD / MWD measurement systems |
| CN106481336B (en) * | 2016-10-31 | 2023-08-11 | 重庆博创声远科技有限公司 | Acoustic wave transmitting transducer and drill collar mounting structure thereof |
| CN111075434B (en) * | 2019-11-29 | 2023-05-26 | 中国石油天然气集团有限公司 | Portable sound source device for acoustic logging instrument array receiving acoustic system field detection and use method thereof |
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| CN201241697Y (en) * | 2008-06-19 | 2009-05-20 | 中国石油天然气集团公司 | Drill-following sound wave dipole transducer |
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| FR2779289B1 (en) * | 1998-05-29 | 2000-09-01 | Thomson Csf | SOUND UNIDIRECTIONAL TRANSDUCER WITH SURFACE ACOUSTIC WAVES |
| CN2428224Y (en) * | 1999-12-30 | 2001-05-02 | 鄞云光 | Strong-anti-corrosion supersonic transducer |
| US6712138B2 (en) * | 2001-08-09 | 2004-03-30 | Halliburton Energy Services, Inc. | Self-calibrated ultrasonic method of in-situ measurement of borehole fluid acoustic properties |
| CN202170793U (en) * | 2011-05-17 | 2012-03-21 | 中国科学院声学研究所 | Logging-while-drilling sound wave logging device and transmitting transducer |
| CN202348264U (en) * | 2011-12-11 | 2012-07-25 | 贵州航天凯山石油仪器有限公司 | Fastening structure of ultrasonic transducer |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201241697Y (en) * | 2008-06-19 | 2009-05-20 | 中国石油天然气集团公司 | Drill-following sound wave dipole transducer |
Non-Patent Citations (1)
| Title |
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| 《从换能器技术的变化看声波测井技术的发展》;乔文孝等;《物理》;20111231;第40卷(第2期);第99-105页 * |
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Inventor after: Lu Junqiang Inventor after: Ju Xiaodong Inventor after: Qiao Wenxiao Inventor after: Zhao Honglin Inventor after: Che Xiaohua Inventor before: Lu Junqiang Inventor before: Ju Xiaodong Inventor before: Qiao Wenxiao Inventor before: Zhao Honglin |
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Free format text: CORRECT: INVENTOR; FROM: LU JUNQIANG JU XIAODONG QIAO WENXIAO ZHAO HONGLIN TO: LU JUNQIANG JU XIAODONG QIAO WENXIAO ZHAO HONGLIN CHE XIAOHUA |
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