CN111337983B

CN111337983B - Optical fiber hydrophone

Info

Publication number: CN111337983B
Application number: CN201811551107.XA
Authority: CN
Inventors: 潘勇; 段胜男; 游红娟; 王宁博; 陈森; 汪志; 芦志伟; 努尔买买提·吾买尔江; 李士建; 黄勇
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2018-12-18
Filing date: 2018-12-18
Publication date: 2022-03-29
Anticipated expiration: 2038-12-18
Also published as: CN111337983A

Abstract

The invention provides an optical fiber hydrophone, which is used for monitoring a steam cavity and comprises: an acoustically transparent sleeve, which is acoustically transparent; the hydrophone unit penetrates through the sound-transmitting sleeve; the support shaft is connected with the hydrophone element, and the first end of the sound-transmitting sleeve is sleeved on the support shaft; the second end of the sound-transmitting sleeve is sleeved on the supporting seat. Therefore, the hydrophone elements can be protected and supported by the transparent sleeve, the support shaft and the support seat, and the optical fiber hydrophone can be applied to monitoring a steam cavity in an oil reservoir environment. Therefore, the fiber optic hydrophone can be used for monitoring the micro seismic waves in the reservoir, and the steam cavity can be accurately monitored so as to obtain the development rule of the steam cavity.

Description

Optical fiber hydrophone

Technical Field

The invention relates to the technical field of oil and gas field exploration and development, in particular to an optical fiber hydrophone.

Background

In the development process of SAGD (steam assisted gravity drainage), the understanding of the development rule of the steam cavity and the accurate mastering of the spreading form and speed of the front edge of the steam cavity are important foundations for the successful development of SAGD. At present, four-dimensional earthquake, inclinometer or potential method, numerical simulation and other methods are generally adopted at home to know the development rule of the steam cavity, the defects of high cost, poor continuity, model limitation and the like exist, the monitoring on the steam cavity is not accurate enough, and the production requirement cannot be met. In the process of steam injection in SAGD development, along with the rise of bottom hole pressure, the front edge of flowing pressure in a reservoir stratum moves and the fluid pressure in pores is transmitted, micro cracks are induced to be generated, and then a series of micro seismic waves which propagate to the periphery are generated.

Disclosure of Invention

The invention provides an optical fiber hydrophone, which aims to solve the problem that the monitoring of a steam cavity is inaccurate in the prior art.

In order to solve the above problems, the present invention provides an optical fiber hydrophone for vapor cavity monitoring, including: an acoustically transparent sleeve, which is acoustically transparent; the hydrophone unit penetrates through the sound-transmitting sleeve; the support shaft is connected with the hydrophone element, and the first end of the sound-transmitting sleeve is sleeved on the support shaft; the second end of the sound-transmitting sleeve is sleeved on the supporting seat.

Furthermore, the support shaft is of a hollow structure, the cavity of the support shaft is used for penetrating the optical fibers, the side wall of the support shaft is provided with an injection hole, and the injection hole is used for injecting liquid into the cavity between the support shaft and the sound transmission sleeve.

Further, have first spacing protruding muscle on the outer circumference of back shaft, first spacing protruding muscle is used for carrying on spacingly to the sound-transparent sleeve, and optic fibre hydrophone still includes: the first winding wire is wound on the first end of the sound-transmitting sleeve so as to fixedly connect the first end of the sound-transmitting sleeve with the support shaft.

Furthermore, the support shaft comprises a first shaft section and a second shaft section, the diameter of the first shaft section is larger than that of the second shaft section, the first end of the sound-transmitting sleeve is sleeved on the first shaft section, and the second shaft section penetrates through the hydrophone element and the support seat.

Further, the support shaft further includes: and the limiting ring is arranged on the outer circumference of the second shaft section and is used for being abutted against one end of the hydrophone element.

Further, the fiber optic hydrophone further comprises: and the fastener is connected to the second shaft section and used for limiting the other end of the hydrophone element.

Further, have annular groove in the supporting seat, the optic fibre hydrophone still includes: and the sealing ring is sleeved on the second shaft section and matched with the annular groove.

Further, the outer circumference of supporting seat has the spacing protruding muscle of second, and the spacing protruding muscle of second is used for carrying on spacingly to the sound-transparent sleeve, and optic fibre hydrophone still includes: and the second winding wire is wound at the second end of the sound-transmitting sleeve so as to fixedly connect the second end of the sound-transmitting sleeve with the supporting seat.

Further, the acoustically transparent sleeve is made of neoprene or butyl rubber.

Further, the fiber optic hydrophone further comprises: and the protective cap is arranged on the support shaft and positioned in the sound-transmitting sleeve, and the optical fiber led out from the hydrophone element is connected with the optical fiber led out from the support shaft in the protective cap.

By applying the technical scheme of the invention, the sound-transmitting sleeve, the hydrophone elements, the supporting shaft and the supporting seat are arranged in the optical fiber hydrophone, so that the optical fiber hydrophone can play a role in protecting and supporting the hydrophone elements through the sound-transmitting sleeve, the supporting shaft and the supporting seat, and can be applied to monitoring a steam cavity in an oil reservoir environment. Therefore, the fiber optic hydrophone can be used for monitoring the micro seismic waves in the reservoir, and the steam cavity can be accurately monitored so as to obtain the development rule of the steam cavity.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a fiber optic hydrophone provided by an embodiment of the invention;

FIG. 2 shows a cross-sectional view of FIG. 1;

fig. 3 shows a schematic structural view of the support shaft of fig. 1.

Wherein the figures include the following reference numerals:

210. an acoustically transparent sleeve; 220. a hydrophone element; 230. a support shaft; 231. an injection hole; 232. a first limit convex rib; 233. a first shaft section; 234. a second shaft section; 235. a limiting ring; 240. a supporting seat; 241. a second limit convex rib; 251. a first winding wire; 252. a second winding wire; 260. a fastener; 270. a seal ring; 280. a protective cap.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1 to 3, an embodiment of the present invention provides a fiber optic hydrophone for vapor cavity monitoring, including: an acoustically transparent sleeve 210 that is acoustically transparent; a hydrophone element 220 inserted into the acoustically transparent sleeve 210; a support shaft 230 connected to the hydrophone unit 220, wherein a first end of the acoustically transparent sleeve 210 is sleeved on the support shaft 230; the support base 240 and the second end of the acoustically transparent sleeve 210 are fitted over the support base 240. Therein, the hydrophone elements 220 are sensors capable of detecting microseismic waves. An acoustic-transparent sleeve 210, a hydrophone element 220, a supporting shaft 230 and a supporting seat 240 are arranged in the optical fiber hydrophone, so that the hydrophone element 220 can be protected and supported by the acoustic-transparent sleeve 210, the supporting shaft 230 and the supporting seat 240, and the optical fiber hydrophone can be applied to an oil reservoir environment to monitor a steam cavity. Therefore, the fiber optic hydrophone can be used for monitoring the micro seismic waves in the reservoir, and the steam cavity can be accurately monitored so as to obtain the development rule of the steam cavity.

Specifically, the support shaft 230 is a hollow structure, the cavity of the support shaft 230 is used for the optical fiber to pass through, the sidewall of the support shaft 230 is provided with an injection hole 231, and the injection hole 231 is used for injecting liquid into the cavity between the support shaft 230 and the sound-transmitting sleeve 210. In the using process, because the fiber optic hydrophone needs to be placed underground at different depths, the environmental pressure is different, so that the pressure in the sound-transmitting sleeve 210 of the fiber optic hydrophone needs to be adjusted to balance with the external pressure, otherwise, the performance of the fiber optic hydrophone is affected. At this time, a pressure balance medium such as acoustically transparent silicone oil may be injected into the acoustically transparent sleeve 210 by connecting the hollow support shaft 230 through a specific hydraulic control system, and a balance pressure may be set in advance. Therefore, the internal pressure of the optical fiber hydrophone can be adjusted as required, and the underground environmental pressure is balanced after the optical fiber hydrophone enters the well, so that the sensitivity of the hydrophone element 220 is not influenced by the environmental pressure.

As shown in fig. 1, the supporting shaft 230 has a first limiting rib 232 on the outer circumference thereof, the first limiting rib 232 is used for limiting the sound-transparent sleeve 210, and the optical fiber hydrophone further includes: and a first winding wire 251 wound around the first end of the acoustic sleeve 210 to fixedly connect the first end of the acoustic sleeve 210 with the support shaft 230. Such that the first limiting rib 232 limits the position of the sound-transmitting sleeve 210. Moreover, the first limiting convex rib 232 may be provided in plurality, and the first winding wire 251 may be wound in the groove between two adjacent first limiting convex ribs 232 to improve the fixing effect.

In this embodiment, the supporting shaft 230 includes a first shaft section 233 and a second shaft section 234, the diameter of the first shaft section 233 is greater than the diameter of the second shaft section 234, the first end of the sound-transmitting sleeve 210 is sleeved on the first shaft section 233, and the second shaft section 234 is inserted through the hydrophone element 220 and the supporting seat 240. This allows the support shaft 230, the hydrophone elements 220 and the support base 240 to be connected together, which improves the structural strength of the fiber optic hydrophone.

In the present embodiment, the support shaft 230 further includes: and a limiting ring 235 arranged on the outer circumference of the second shaft section 234, wherein the limiting ring 235 is used for abutting against one end of the hydrophone element 220. The hydrophone elements 220 may be restrained by a restraint ring 235.

In this embodiment, the fiber optic hydrophone further includes: and a fastener 260 attached to the second shaft section 234, the fastener 260 being used to retain the other end of the hydrophone element 220. This secures the hydrophone element 220 to the second shaft section 234 by the cooperation of the fasteners 260 and the stop collar 235. In particular, the fastener 260 may be provided as a nut.

In this embodiment, the supporting base 240 has an annular groove therein, and the optical fiber hydrophone further includes: and a seal ring 270 fitted over the second shaft section 234 and engaging the annular groove. The sealing effect of the second shaft section 234 and the supporting seat 240 can be improved by providing the sealing ring 270.

In this embodiment, the outer circumference of the supporting base 240 has a second limiting rib 241, the second limiting rib 241 is used for limiting the sound-transmitting sleeve 210, and the optical fiber hydrophone further includes: a second wrapping wire 252 is wrapped around the second end of the acoustically transparent sleeve 210 to fixedly couple the second end of the acoustically transparent sleeve 210 to the support base 240. Such that the second limiting rib 241 limits the position of the sound-transmitting sleeve 210. Moreover, the second limit beads 241 may be provided in plurality, and the second winding wire 252 may be wound in the groove between two adjacent second limit beads 241 to improve the fixing effect.

In the present embodiment, the sound-transmitting sleeve 210 is made of neoprene or butyl rubber, and has acoustic impedance characteristics well matched with water, good water tightness, extremely low water absorption and water permeability, and a long service life.

In this embodiment, the fiber optic hydrophone further includes: and a protective cap 280 disposed on the support shaft 230 within the acoustically transparent sleeve 210, the optical fibers exiting from the hydrophone cell 220 being connected to the optical fibers exiting from the support shaft 230 within the protective cap 280. The protective cap 280 may provide attachment and protection to the structure.

The optical fiber hydrophone is an underwater acoustic signal sensor established on the basis of optical fiber and photoelectron technologies, converts underwater acoustic vibration into optical signals through high-sensitivity optical coherent detection, and transmits the optical signals to a signal processing system through optical fibers to extract the acoustic signals. At present, the optical fiber hydrophone is mainly used for marine underwater monitoring and is not suitable for microseism monitoring of oil and gas field exploration and development. Through the technical scheme, the optical fiber hydrophone can be applied to monitoring the micro seismic waves caused by the steam cavity, so that the development rule of the steam cavity and the front edge distribution form and speed of the steam cavity can be better known and predicted.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

Claims

1. A fiber optic hydrophone for vapor cavity monitoring, comprising:

an acoustically transparent sleeve (210) that is acoustically transparent;

a hydrophone element (220) disposed through the acoustically transparent sleeve (210);

a support shaft (230) connected with the hydrophone element (220), wherein the first end of the sound-transmitting sleeve (210) is sleeved on the support shaft (230);

a support base (240), wherein the second end of the sound-transmitting sleeve (210) is sleeved on the support base (240);

the support shaft (230) is of a hollow structure, a cavity of the support shaft (230) is used for allowing an optical fiber to penetrate through, an injection hole (231) is formed in the side wall of the support shaft (230), and the injection hole (231) is used for injecting liquid into the cavity between the support shaft (230) and the sound-transmitting sleeve (210).

2. The fiber optic hydrophone of claim 1, wherein the support shaft (230) has a first limit rib (232) on an outer circumference thereof, the first limit rib (232) being configured to limit the position of the acoustically transparent sleeve (210), the fiber optic hydrophone further comprising:

a first winding wire (251) wound around the first end of the acoustically transparent sleeve (210) to fixedly connect the first end of the acoustically transparent sleeve (210) to the support shaft (230).

3. The fiber optic hydrophone of claim 1, wherein the support shaft (230) comprises a first shaft segment (233) and a second shaft segment (234), the first shaft segment (233) having a diameter greater than a diameter of the second shaft segment (234), the first end of the acoustically transparent sleeve (210) fitting over the first shaft segment (233), the second shaft segment (234) passing through the hydrophone element (220) and the support base (240).

4. The fiber optic hydrophone of claim 3, wherein the support shaft (230) further comprises:

a stop collar (235) disposed on an outer circumference of the second shaft section (234), the stop collar (235) for abutting one end of the hydrophone element (220).

5. The fiber optic hydrophone of claim 4, further comprising:

a fastener (260) attached to the second shaft section (234), the fastener (260) for restraining the other end of the hydrophone element (220).

6. The fiber optic hydrophone of claim 3, wherein the support block (240) has an annular groove therein, the fiber optic hydrophone further comprising:

and the sealing ring (270) is sleeved on the second shaft section (234) and is matched with the annular groove.

7. The fiber optic hydrophone of claim 1, wherein the support base (240) has a second limiting rib (241) on an outer circumference thereof, the second limiting rib (241) being configured to limit the position of the acoustically transparent sleeve (210), the fiber optic hydrophone further comprising:

a second winding wire (252) wound around the second end of the acoustically transparent sleeve (210) to fixedly connect the second end of the acoustically transparent sleeve (210) to the support base (240).

8. The fiber optic hydrophone of claim 1, wherein the acoustically transparent sleeve (210) is made of neoprene or butyl rubber.

9. The fiber optic hydrophone of claim 1, further comprising:

a protective cap (280) disposed on the support shaft (230) and located within the acoustically transparent sleeve (210), the optical fibers exiting from the hydrophone cell (220) being connected with the optical fibers exiting from the support shaft (230) within the protective cap (280).