CN217106979U - Optical cable positioning device and casing fracturing system in oil well - Google Patents

Abstract

The utility model discloses an optical cable positioning device and a sleeve fracturing system in an oil well, wherein the positioning device comprises a plurality of positioning arms made of elastic materials and a telescopic mechanism for expanding or stretching the positioning arms and positioning in the oil well, and each positioning arm is provided with a vibration device, a driving circuit for driving the vibration device and a power supply for supplying power to the driving circuit; the two ends of all the positioning arms are fixed on the telescopic mechanism, and the end parts of all the telescopic arms positioned on the same side of the telescopic mechanism are positioned on the same circumferential surface; the heights of the vibration devices on each positioning arm are the same, and the vibration signals sent by the vibration devices are different. The positioning device provided by the scheme solves the problem that the position of the existing optical cable is difficult to determine after the optical cable is lowered into the well, so that the optical cable can be damaged in the sleeve pressing process.

Description

Optical cable positioning device and casing fracturing system in oil well

technical field

The utility model belongs to the technical field of oil and gas exploration, in particular to an optical cable positioning device and a positioning method in an oil well, a casing fracturing system and a method.

Background technique

Oil is an extremely important material, and with the reduction of oil resources in my country, the difficulty of mining increases, the consumption of resources increases, and the degree of dependence on foreign countries increases, all of which have adverse effects on national security. Increasing exploration and development efforts, developing new technologies, reducing traditional exploration costs, and increasing oil production are all important directions for solving the country's lack of energy. The exploitation of oil and gas resources usually adopts the measures of staged fracturing of oil wells to squeeze the casing out of the cracks, so that the oil can flow into the casing more smoothly.

Because optical fiber has the advantages of corrosion resistance, high temperature resistance, strong anti-interference ability, high reliability and low engineering application cost, it can better withstand the harsh environment in oil wells and then enter the line of sight of the oil exploration industry. At present, distributed optical fiber sensors The technology has huge application potential in the field of oil and gas exploitation. Optical fiber is used as a "seismic detector" to act as a proxy for traditional electronic geophones to achieve seamless detection in wells.

When applying distributed optical fiber sensing technology to oil wells, especially mining, one of the basic conditions for collecting high-quality signals is that the optical cable is complete. After the optical cable is laid, the position of the optical cable in the casing is uncertain. If fracturing technology is implemented rashly , may damage the optical cable and affect subsequent data collection.

Utility model content

In view of the above-mentioned deficiencies in the prior art, the optical cable positioning device and positioning method in the oil well, the casing fracturing system and the method provided by the present invention solve the problem that the existing optical cable is difficult to determine the position of the optical cable after it goes down the well, which makes it difficult to determine the position of the optical cable during the casing pressure application process. will damage the fiber optic cable.

In order to achieve the above-mentioned purpose of the invention, the technical scheme adopted by the present utility model is:

In the first aspect, an optical cable positioning device in an oil well is provided, which includes a plurality of positioning arms made of elastic materials and a telescopic mechanism for expanding or stretching the positioning arms and positioning in the oil well, and each positioning arm is provided with a vibration A device, a drive circuit for driving the vibration device, and a power supply for supplying power to the drive circuit;

Both ends of all positioning arms are fixed on the telescopic mechanism, and the ends of all telescopic arms located on the same side of the telescopic mechanism are located on the same circumferential surface; the vibration devices on each positioning arm are at the same height, and the vibration signals sent out are all at the same height. Are not the same.

In a second aspect, a casing fracturing system in an oil well is provided, which includes a plurality of positioning arms made of elastic materials, a telescopic rod for expanding/stretching the positioning arms, and a short shock-absorbing rod fixed to the end of the telescopic rod. For the perforating gun, a vibration device, a drive circuit for driving the vibration device and a power supply for supplying power to the drive circuit are installed on each positioning arm;

Both ends of all positioning arms are fixed on the telescopic rod, and the ends of all telescopic arms located on the same side of the telescopic rod are located on the same circumferential surface; the vibration devices on each positioning arm are at the same height, and the vibration signals sent out are all the same. Are not the same.

The beneficial effects of the present invention are as follows: since the positioning arm of this solution is fixed on the same circumferential surface of the telescopic mechanism, when it enters the casing to position the optical cable, it is equivalent to dividing the casing into several small areas. When the vibrating arm corresponds to the strong vibration signal, the positioning device of the telescopic mechanism can be used to locate the specific area where the positioning arm is located in the casing, that is, find the specific area where the optical cable is close to the casing.

In the process of oil well fracturing, the position of the muzzle of the perforating gun can be adjusted according to the specific area where the optical cable is close to the casing, so that the muzzle avoids the optical cable, so as to avoid damage to the optical cable, reduce the risk of optical cable breakage, and improve the use of the optical cable. The efficiency has laid a foundation for the subsequent use of light sensing technology for oil and gas exploration in oil wells.

When the positioning arm is used in combination with the perforating gun, the optical cable can be positioned at the same time as fracturing, which improves the work efficiency, and does not require a positioning module during the fracturing operation, reducing the cost. In addition, the device, system and method provided by this solution are suitable for various well conditions, including vertical wells, deviated wells, horizontal wells, and the like.

Description of drawings

FIG. 1 is a schematic structural diagram of an embodiment of an optical cable positioning device in an oil well.

Fig. 2 is a schematic structural diagram of the positioning arm in the oil well after the positioning device for the optical cable in the oil well is arranged in the casing in Fig. 1 when the positioning arm is in compression.

FIG. 3 is a flow chart of a method for positioning an optical cable by an optical cable positioning device in an oil well.

FIG. 4 is a schematic structural diagram of a casing fracturing system in an oil well.

Among them, 1, positioning arm; 2, telescopic mechanism; 21, telescopic rod; 22, positioning module; 3, vibration device; 4, optical cable; 5, casing; 6, demodulation device; 7, connecting rod; 8, shooting Hole gun; 9, shock-absorbing short rod.

Detailed ways

The specific embodiments of the present invention are described below to facilitate those skilled in the art to understand the present invention, but it should be clear that the present invention is not limited to the scope of the specific embodiments. Various changes are within the spirit and scope of the present utility model defined and determined by the appended claims, and these changes are obvious, and all utility model creations utilizing the concept of the present utility model are included in the protection list.

As shown in Figures 1 and 2, the optical cable positioning device in the oil well provided by this solution includes several positioning arms 1 made of elastic materials and a telescopic mechanism 2 for expanding or stretching the positioning arms 1 and positioning in the oil well. A vibration device 3 , a drive circuit for driving the vibration device 3 and a power supply for supplying power to the drive circuit are installed on the arm 1 .

Both ends of all positioning arms 1 are fixed on the telescopic mechanism 2, and the ends of all telescopic arms located on the same side of the telescopic mechanism 2 are located on the same circumferential surface; the vibration devices 3 on each positioning arm 1 are at the same height, and The vibration signals sent out are all different.

The way that the vibration signals on all positioning arms 1 are different is that the vibration devices 3 send vibration signals of different frequencies, or the vibration devices 3 on each positioning arm 1 send vibration signals of different codes. The vibration device 3 on each positioning arm 1 sends out vibration signals of different frequencies, or the vibration device 3 on each positioning arm 1 sends out vibration signals with different codes.

After the above-mentioned optical cable positioning device in the oil well is adopted in this scheme, the telescopic arm located on the telescopic mechanism 2 can divide the casing 5 into several areas, and then cooperate with the analysis device connected with the optical cable 4 to determine which place has the strongest vibration signal. Therefore, the position of the optical cable 4 in the sleeve 5 can be accurately determined.

During implementation, preferably, the telescopic mechanism 2 of this solution may include a telescopic rod 21 for installing the positioning arm 1 and a positioning module 22 installed on the telescopic rod 21 not located between the two ends of the positioning arm 1 . The positioning module 22 is a three-axis acceleration sensor.

After the telescopic mechanism 2 adopts the above structure, the optical cables 4 at all the positions of the casing 5 that need to be fracturing can be positioned first, and when all the positions that need fracturing are determined, based on the recorded positions of the optical cables 4, a perforating gun is used. 8. Perform radiation avoidance of the optical cable 4 in the sleeve 5.

When fracturing the casing 5, the optical cable positioning device in the oil well can be used to locate all the optical cables 4 in the casing 5 where fracturing is required, and then the perforating gun 8 can be used for the fracturing operation; The optical cable positioning device in the oil well of this scheme can be fixed to the perforating gun 8. When using, the optical cable is first positioned with the positioning device. After the positioning is completed, the position of the muzzle of the perforating gun 8 can be directly adjusted to perform the fracturing operation. Then enter the next position of the casing that needs fracturing to perform optical cable positioning and casing fracturing operations.

As shown in FIG. 2 , the installation position of the vibration device 3 is the highest point of the radian of the positioning arm 1 when the positioning arm 1 expands to the maximum radian. After the vibration device 3 adopts this installation position, when the positioning arm 1 expands to contact the casing wall, the vibration signal can be most effectively transmitted to the casing wall.

Referring to FIG. 3 , FIG. 3 shows a flowchart of a method for positioning the optical cable 4 by the optical cable positioning device in the oil well; as shown in FIG. 3 , the method includes steps S1 to S4 .

In step S1, the telescopic mechanism 2 of the optical cable positioning device in the oil well is connected to the connecting rod 7, and the optical cable positioning device in the oil well is moved to a preset position through the connecting rod 7;

In step S2, the telescopic mechanism 2 is activated, and the shortened telescopic mechanism 2 expands the positioning arm 1 until the positioning arm 1 contacts the inner wall of the sleeve 5;

During implementation, the following two methods can be used to determine whether the positioning arm 1 is in contact with the inner wall of the sleeve 5. The first method is:

Start the vibration device 3 to send out vibration signals at intervals, and judge whether the number of vibration signals demodulated by the demodulation device 6 is greater than or equal to 1; if so, the positioning arm 1 is in contact with the inner wall of the casing 5; expansion.

The second method is: adjusting the telescopic mechanism 2 to shorten the preset length, so that the positioning arm 1 is at the maximum expansion amount, and at this time, the maximum cross-sectional diameter of the structure formed by all the positioning arms is larger than the diameter of the casing.

In step S3, all the vibration devices 3 are used to send out vibration signals at intervals, and the demodulation device 6 is used to demodulate the vibration information sent by all the positioning arms 1 received by the optical cable 4; the preferred demodulation device in this scheme is a DAS instrument.

When the number n of the positioning arms 1 is less than or equal to 3, the step A3 also includes rotating the connecting rod at the same time when the vibration signal is sent out at intervals. This arrangement can ensure that each position of the casing is detected to find the position information of the positioning arm corresponding to the strongest vibration signal at a certain moment.

Specifically, the optical cable receives the vibration information sent by all the positioning arms 1, and the DAS instrument demodulates the position information of each positioning arm. When the received vibration signal of a positioning arm is the strongest, it is considered that the optical cable is in the vicinity of the positioning arm. , the position information of the optical cable at the specified sleeve position can be determined.

In step S4, the strongest vibration signal obtained by demodulation is acquired, and according to the positioning information of the telescopic mechanism 2 and the relative position between the positioning arms 1, the position information of the positioning arm 1 with the strongest vibration signal is calculated as the position of the optical cable 4 .

When the positioning of the optical cable at the preset position in the casing 5 by the optical cable positioning device in the oil well is completed or the fracturing is completed, the telescopic mechanism 2 is activated to extend, and the positioning arm 1 can be extended to move to the next preset position of the casing 5 . Set the position, and repeat steps S2 to S4 to locate the position of the optical cable 4 .

Specific instructions for calculating the position information of the positioning arm 1 with the strongest vibration signal:

On the telescopic mechanism 2, once the position of the positioning module 22 relative to the positioning arm 1 is determined, and the relative position between each positioning arm 1 is fixed and known, through the position information of the positioning module 22, the The orientation of a certain positioning arm 1 in the oil well can be determined, and the orientations of all positioning arms 1 in the oil well can be calculated according to the relative positional relationship between the positioning arms 1 .

When implemented, the axis of the telescopic mechanism 2 is preferably coincident with the axis of the sleeve 5; after this setting, it can be ensured that all the positioning arms 1 are in contact with the inner wall of the sleeve 5 at the same time, and the pressure between the inner walls is basically the same, This ensures the most efficient transmission of the vibration signal to the casing wall.

To sum up, after the optical cable 4 is laid out, the external connecting rod 7 can be used to move the positioning device of this solution to any position in the well, and the positioning device can be used to obtain the exact position of the optical cable 4 on the casing 5, so as to avoid During the oil well fracturing process, the optical cable 4 is damaged, and the risk of the optical cable 4 breaking is reduced.

As shown in FIG. 4 , the solution also provides a casing fracturing system in an oil well, which includes a plurality of positioning arms 1 made of elastic materials, a telescopic rod 21 for expanding/stretching the positioning arms 1, and a shock absorbing The short rod 9 is fixed to the perforating gun 8 at the end of the telescopic rod 21 , and each positioning arm 1 is provided with a vibration device 3 , a drive circuit for driving the vibration device 3 and a power supply for supplying power to the drive circuit.

After the short shock-absorbing rod 9 is added between the telescopic rod 21 and the perforating gun 8 , the strong vibration caused by the perforating gun 8 during operation can be prevented from damaging all the structural components above the short shock-absorbing rod 9 .

Both ends of all the positioning arms 1 are fixed on the telescopic rod 21, and the ends of all the telescopic arms located on the same side of the telescopic rod 21 are located on the same circumferential surface; the vibration devices 3 on each positioning arm 1 are at the same height, and The vibration signals sent out are all different.

Compared with the optical cable positioning device in the oil well, the casing fracturing system in the oil well has a perforating gun 8 added. Since the perforating gun 8 itself has a positioning module, the fracturing system does not require additional positioning relative to the positioning device. module.

In order to further improve the positioning accuracy of the casing fracturing system in the oil well, in addition to the positioning module of the perforating gun 8 itself, the casing fracturing system in the oil well can also be provided with a positioning module. The additional positioning module is installed on the positioning arm. 1 on either end of the telescopic rod 21.

Except for the differences mentioned above, the structure and function of other parts of the casing fracturing system in the oil well relative to the optical cable positioning device in the oil well are the same, which will not be repeated here.

The method of fracturing the casing by using the casing fracturing system in the oil well includes:

A1. Connect the telescopic rod 21 of the casing fracturing system in the oil well with the connecting rod 7, and move the casing fracturing system in the oil well to a preset position through the connecting rod 7;

A2. Activate the telescopic rod 21, and the shortened telescopic rod 21 expands the positioning arm 1 until the positioning arm 1 is in contact with the inner wall of the casing 5;

A3. Use all the vibration devices 3 to send out vibration signals at intervals, and use the demodulation device 6 to demodulate the vibration information sent by all the positioning arms 1 received by the optical cable;

A4. Obtain the strongest vibration signal obtained by demodulation, and calculate the position information of the positioning arm 1 with the strongest vibration signal as the location of the optical cable according to the positioning information obtained by the perforating gun 8 and the relative position between the positioning arms 1;

A5. According to the position of the optical cable, adjust the muzzle of the perforating gun 8 to avoid the optical cable, and then perform the fracturing operation on the casing 5.

To sum up, when the positioning arm 1 is used in combination with the perforating gun 8, the optical cable can be positioned while fracturing, which improves work efficiency, reduces positioning modules, and reduces costs.

Claims (4)

1. The optical cable positioning device in the oil well is characterized by comprising a plurality of positioning arms made of elastic materials and a telescopic mechanism for expanding or stretching the positioning arms and positioning in the oil well, wherein each positioning arm is provided with a vibration device, a driving circuit for driving the vibration device and a power supply for supplying power to the driving circuit;

the two ends of all the positioning arms are fixed on the telescopic mechanism, and the end parts of all the telescopic arms positioned on the same side of the telescopic mechanism are positioned on the same circumferential surface; the heights of the vibration devices on each positioning arm are the same, and the vibration signals sent by the vibration devices are different; the telescopic mechanism comprises a telescopic rod used for installing a positioning arm and a positioning module which is not arranged on the telescopic rod between the two ends of the positioning arm.

2. The device as claimed in claim 1, wherein the vibration device is mounted at the highest point of the arc of the positioning arm when the positioning arm is expanded to the maximum arc.

3. The in-well cable positioning device of claim 1, wherein the vibration signals on all positioning arms are different in such a way that the vibration devices emit vibration signals of different frequencies, or the vibration devices on each positioning arm emit vibration signals of different codes.

4. The fracturing system for the inner sleeve of the oil well is characterized by comprising a plurality of positioning arms made of elastic materials, telescopic rods used for expanding/stretching the positioning arms and perforating guns fixed at the tail ends of the telescopic rods through damping short rods, wherein each positioning arm is provided with a vibrating device, a driving circuit used for driving the vibrating device and a power supply used for supplying power to the driving circuit;

the two ends of all the positioning arms are fixed on the telescopic rod, and the end parts of all the telescopic arms positioned on the same side of the telescopic rod are positioned on the same circumferential surface; the heights of the vibration devices on each positioning arm are the same, and the vibration signals sent by the vibration devices are different;

the oil well inner casing fracturing system further comprises a positioning module, and the positioning module is installed on the telescopic rod at any one of the two ends of the positioning arm.

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