Continuous optical fiber for overflow detection

Abstract

The invention relates to the field of well drilling overflow detection, in particular to a continuous optical fiber for overflow detection, which comprises a continuous pipe and an optical fiber, the optical fiber is arranged along the axial direction of the continuous pipe, and a plurality of hoops for fixing the optical fiber are arranged in the axial direction of the continuous pipe; the outer side of the optical fiber is sleeved with a protective sleeve used for protecting the optical fiber. The hoop comprises a first protection piece and a second protection piece, and the first protection piece and the second protection piece are connected through a bolt. The first protection piece and the second protection piece are the same in structure, the first protection piece comprises a first protection block and a second protection block, an embedded sliding block is arranged between the first protection block and the second protection block, and the two sides of the embedded sliding block are connected with the first protection block and the second protection block respectively. All positions in the well can be comprehensively detected, the phenomenon of well kick or blowout is completely eradicated, and precious time is gained for follow-up well shut-in and control measures.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of drilling overflow detection, in particular to a continuous optical fiber for overflow detection. BACKGROUND

[0002] Overflow detection is the core link of well control in drilling operation, and its purpose is to timely and accurately find the invasion of formation fluid, such as oil, gas and water, into the wellbore when it just begins to develop into a serious well kick or blowout, so as to win valuable time for subsequent well shut-in and control measures. However, the current overflow detection device for drilling operation has a detection blind area, and cannot comprehensively detect the overflow risk of all positions in the well, but can only provide data of a single point, which is easy to cause well kick or blowout accidents in undetected positions. SUMMARY

[0003] The purpose of the present application is to provide a continuous optical fiber for overflow detection, which solves the problem of detection blind spot in the current overflow detection in the well.

[0004] In order to achieve the above purpose, the technical solution adopted by the present application is: A continuous optical fiber for overflow detection, comprising a continuous pipe and an optical fiber, the optical fiber is arranged along the axial direction of the continuous pipe, and a plurality of clamps for fixing the optical fiber are arranged in the axial direction of the continuous pipe; a protective sleeve for protecting the optical fiber is sleeved outside the optical fiber.

[0005] Further, the clamp comprises a first protection member and a second protection member, and the first protection member and the second protection member are connected by bolts.

[0006] Further, the first protection member and the second protection member are structurally identical, the first protection member comprises a first protection block and a second protection block, and an embedded sliding block is arranged between the first protection block and the second protection block, and the embedded sliding block is detachably connected with the first protection block and the second protection block.

[0007] Further, the first protection block and the second protection block jointly form a connecting hole.

[0008] Further, a limiting groove is arranged on the connecting hole, a first fixing hole for fixing the embedded sliding block is opened on the limiting groove, a second fixing hole is arranged on the embedded sliding block, and the bolts pass through the first fixing hole and the second fixing hole in sequence to connect the embedded sliding block on the first protection block and the second protection block.

[0009] Further, the embedded sliding block comprises a limiting block, and the second fixing hole is arranged on the limiting block, and the limiting block is arranged in the limiting groove.

[0010] Further, the first protection piece and the second protection piece are provided with mounting holes, and bolts pass through the first protection piece and the second protection piece in sequence to connect the first protection piece and the second protection piece.

[0011] Further, the optical fiber is provided with a distributed temperature sensor and a distributed acoustic sensor.

[0012] Compared with the prior art, the present application has the following advantages and beneficial effects: The present application can fix the optical fiber on the coiled tubing through the hoop, can lower the coiled tubing with the optical fiber into the production string or drill pipe to reach the position of the well bottom, can detect overflow of all positions from the well bottom to the well head, and can prevent well kick or blowout. The present application can comprehensively detect all positions in the well, can prevent well kick or blowout, and can win valuable time for subsequent shut-in and control measures. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a schematic diagram of a continuous optical fiber for overflow detection.

[0014] Figure 2 It is a profile view of a continuous optical fiber for overflow detection.

[0015] Figure 3 It is a schematic diagram of a hoop.

[0016] Figure 4 It is a schematic diagram of a first protection block and a second protection block.

[0017] Figure 5 It is a schematic diagram of an embedded slider. DETAILED DESCRIPTION

[0018] As shown in Figure 1 and 2 , a continuous optical fiber for overflow detection comprises a coiled tubing 1, a plurality of optical fibers 2 are placed outside the coiled tubing 1 and are fixed on the coiled tubing 1 through a hoop 3, the optical fiber 2 is arranged between the hoop 3 and the coiled tubing 1; the optical fiber 2 is provided with a distributed temperature sensor and a distributed acoustic sensor. The optical fiber 2 is fixed on the coiled tubing 1 through the hoop 3, two hoops 3 are fixed on the coiled tubing 1 through mounting holes 4, and a protection sleeve for protecting the optical fiber 2 is sleeved outside the optical fiber 2. The coiled tubing 1 with the optical fiber 2 is lowered into the production string or drill pipe, and can be lowered to the position of the well bottom. One end of the coiled tubing 1 is connected to a ground interrogation unit. The interrogation unit emits a laser pulse and receives a returned scattered signal. Finally, a computer software processes massive acoustic sensor and temperature sensor data in real time, and converts the data into an acoustic spectrum graph and a temperature profile along the well depth.

[0019] Distributed acoustic sensing technology works by utilizing the backscattering Rayleigh effect generated when laser light propagates in optical fiber 2. When vibrations or acoustic events in the environment surrounding optical fiber 2 (such as fluid flow or gas leakage) induce minute stress or strain on the fiber 2, they alter the phase and amplitude of the scattered light. Distributed acoustic sensors can then "hear" sounds within the wellbore. Overflow, especially in the initial stages of gas overflow, produces unique sound frequencies. Inflow / outflow sounds, bubble sounds, and other similar noises can be captured and located by the distributed acoustic sensors.

[0020] Distributed temperature sensing technology operates on the principle of Raman scattering. Raman scattering is extremely sensitive to temperature; by measuring the intensity ratio of the anti-Stokes light to the Stokes light, the temperature along fiber optic cable 2 can be calculated. Distributed temperature sensors can "sense" temperature. When formation fluids (especially gases) flow into the wellbore, they can cause temperature anomalies.

[0021] This device secures the sensing fiber 2 to the outer wall of the continuous tube 1 by bundling it with a clamp 3, and using a protective sleeve, adhesive, and embedding method. The clamp 3 fixes the fiber 2 and the protective sleeve to the continuous tube 1, enabling the fiber 2 to detect overflow. The protective sleeve is typically a flexible sleeve specifically designed to protect the fragile fiber 2. It primarily serves as a mechanical protective layer, providing additional, robust external protection for the fiber 2 during or after cabling. It effectively prevents the fiber 2 from being squeezed, stepped on, scratched, or worn, avoiding breakage or performance degradation due to external impact. It also possesses certain waterproof, moisture-proof, dustproof, and chemical corrosion-resistant capabilities, protecting the fiber 2 from harsh environments. The main material of the fiber 2 protective sleeve in this invention is a high-strength metal armor layer wrapped under a high-density polyethylene outer layer.

[0022] like Figures 3 to 5As shown, the clamp 3 includes a first protective member 31 and a second protective member 32, which are connected by bolts. The first protective member 31 and the second protective member 32 have the same structure. The first protective member 31 includes a first protective block 311 and a second protective block 312. An embedded slider 313 is provided between the first protective block 311 and the second protective block 312, with its two sides connected to the first protective block 311 and the second protective block 312 respectively. The first protective block 311 and the second protective block 312 together form a connecting hole. A limiting groove 314 is provided on the connecting hole. The limiting groove 314 has a first fixing hole for fixing the embedded slider 313, and a second fixing hole is provided on the embedded slider 313. Bolts pass through the first fixing hole and the second fixing hole in sequence to connect the embedded slider 313 to the first protective block 311 and the second protective block 312. The embedded slider 313 includes a limiting block, with the second fixing hole located on the limiting block, which is placed in the limiting groove 314. Both the first protective component 31 and the second protective component 32 are provided with mounting holes 4. Bolts pass through the first protective component 31 and the second protective component 32 in sequence to connect the first protective component 31 and the second protective component 32. The first protective component 31 and the second protective component 32 can be disassembled, so that the optical fiber 2 can be repaired and replaced at any time.

[0023] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A continuous optical fiber for overflow detection, characterized by, The continuous tube and the optical fiber are arranged along the axial direction of the continuous tube, and a plurality of hoops for fixing the optical fiber are arranged in the axial direction of the continuous tube; the optical fiber is sleeved with a protective sleeve for protecting the optical fiber.

2. A continuous optical fiber for overflow detection according to claim 1, wherein, Each of the hoops comprises a first protection member and a second protection member, and the first protection member and the second protection member are connected by bolts.

3. A continuous optical fiber for overflow detection according to claim 2, wherein, The first protection member and the second protection member are identical in structure, the first protection member comprises a first protection block and a second protection block, and an embedded sliding block is arranged between the first protection block and the second protection block, and the embedded sliding block is detachably connected with the first protection block and the second protection block.

4. A continuous optical fiber for overflow detection according to claim 3, wherein, The first protection block and the second protection block jointly form a connecting hole.

5. A continuous optical fiber for overflow detection according to claim 4, wherein, A limiting groove is arranged on the connecting hole, a first fixing hole for fixing the embedded sliding block is formed in the limiting groove, a second fixing hole is arranged on the embedded sliding block, and the embedded sliding block is connected to the first protection block and the second protection block by the bolts passing through the first fixing hole and the second fixing hole in sequence.

6. A continuous optical fiber for overflow detection according to claim 5, wherein, The embedded sliding block comprises a limiting block, and the second fixing hole is arranged on the limiting block, and the limiting block is arranged in the limiting groove.

7. A continuous optical fiber for overflow detection according to claim 2, wherein, Mounting holes are arranged on the first protection member and the second protection member, and the first protection member and the second protection member are connected by the bolts passing through the first protection member and the second protection member in sequence.

8. A continuous optical fiber for overflow detection according to claim 1, wherein, The optical fiber is provided with a distributed temperature sensor and a distributed acoustic sensor.

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