Azimuthally acoustic imaging logging while drilling (LWD) apparatus

Patent metadata

Field	Value
Publication number	US-10364670-B1
Application number	US-201816123650-A
Country	US
Kind code	B1
Filing date	Sep 6, 2018
Priority date	May 9, 2018
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

An azimuthally acoustic imaging logging while drilling (LWD) apparatus employs two sets of transmitting transducers to excite multipole mode waves. One set is high-frequency monopole and polarized pole transmitting transducers, and the other set is low-frequency dipole and quadrupole transmitting transducers. Separation of a high-frequency transmitting state from a low-frequency transmitting state is realized by using a dual-row transmission solution. Each set of transmitting transducers operates at transducer resonance points through a matching circuit, thereby greatly increasing the transmitted energy. An operation mode of the azimuthally acoustic imaging LWD apparatus includes four kinds of transmitting modes of monopole, dipole, quadrupole and polarized pole; in terms of a sound insulator, a combined sound insulation mode of inner notch groove and inner reducers and tungsten rods is adopted; and signal reception may be realized by employing a high-sensitivity receiving transducer, which can effectively realize the signal reception.

First claim

What is claimed is:

1. An azimuthally acoustic imaging logging while drilling (LWD) apparatus, comprising:
a drill collar having a first section and a second section,
a low-frequency transmitting transducer, a high-frequency transmitting transducer, and a transmitting integrated circuit unit disposed on the first section of the drill collar;
a receiving transducer and a receiving integrated circuit unit disposed on the second section of the drill collar;
a sound insulator disposed between the first section and the second section;
a trace rod extending through the sound insulator, wherein a first end of the trace rod is connected with the transmitting integrated circuit unit, and a second end of the trace rod is connected with the receiving integrated circuit unit,
wherein, during operation, the low-frequency transmitting transducer and the high-frequency transmitting transducer both operate at their respective transducer resonance points.

2. The azimuthally acoustic imaging LWD apparatus according to claim 1 , wherein the low-frequency transmitting transducer has a resonance point in a range of 2 kHz to 5 kHz, and the high-frequency transmitting transducer has a resonance point in a range of 10 kHz to 15 kHz.

3. The azimuthally acoustic imaging LWD apparatus according to claim 2 , wherein the high-frequency transmitting transducer and the low-frequency transmitting transducer affixed to an outer wall in the first section of the drill collar and are connected with the transmitting integrated circuit unit.

4. The azimuthally acoustic imaging LWD apparatus according to claim 2 , wherein the receiving transducer is affixed to an outer wall in the second section of the drill collar and is connected to the receiving integrated circuit unit.

5. The azimuthally acoustic imaging LWD apparatus according to claim 1 , wherein the receiving transducer comprises a plurality of ceramic tiles encapsulated onto an elongated support, wherein a signal preamplifier circuit module is disposed on the elongated support.

6. The azimuthally acoustic imaging LWD apparatus according to claim 5 , wherein an outer surface of the trace rod has notch grooves.

7. The azimuthally acoustic imaging LWD apparatus according to claim 1 ,
the sound insulator comprises a collar with notch grooves on an inner wall, and a plurality of hard alloy rods embedded in an outer wall of the collar, wherein the notch grooves on the inner wall of the collar comprise inner reducer structure grooves and inner notch grooves with constant diameters and widths, wherein the inner reducer structure grooves are disposed at one end of the sound insulator proximate to the receiving transducer.

8. The azimuthally acoustic imaging LWD apparatus according to claim 7 , wherein the hard alloy rods further include one or more first rods having a larger diameter and one or more second rods having a smaller diameter, wherein the first rods are embedded at non-notch groove positions, and the second rods are embedded at notch groove positions.

9. The azimuthally acoustic imaging LWD apparatus according to claim 8 , wherein the first rod is a tungsten rod having a diameter in a range of 25 mm to 40 mm and a length in a range of 25 mm to 30 mm; and the second tungsten rod having a diameter in a range of 10 mm to 15 mm and a length in a range of 5 mm to 8 mm.

10. The azimuthally acoustic imaging LWD apparatus according to claim 7 , wherein the hard alloy rods are tungsten rods.

Assignees

• Inst Geology & Geophysics Cas

Inventors

• Zheng Jian
• Chen Wenxuan
• Di Qingyun
• Wang Zili
• Sun Yuntao
• Yang Yongyou
• Zhang Wenxiu

Classifications

• G01V1/52 Primary

  Structural details · CPC title

• G01V2200/16

  Measure-while-drilling or logging-while-drilling · CPC title

• G01V1/44

  using generators and receivers in the same well (G01V1/52 takes precedence) · CPC title

• G01V2001/526

  Mounting of transducers · CPC title

• E21B47/14 Primary

  using acoustic waves · CPC title