1. A method of continuous run in of a fiber optic downhole cable, the method comprising:

the optical cable penetrates through the packer and the monitoring part in advance, and when the optical cable needs to be lowered into the production well, the optical cable is lowered to the production well in a rotating mode through the rotating drum; the packer and the monitoring piece are fixed and lowered to a required position through a fixing and feeding mechanism.

2. A method of continuously running a downhole fiber optic cable according to claim 1, further comprising pre-connecting the fiber optic cable to the monitor in advance; preferably, the method further comprises controlling the running speed of the optical cable, the packer and the monitoring element through a control system, and reading the running depth of the optical cable, the packer and the monitoring element through a depth recording mechanism.

3. A method of continuous downhole wireline running according to claim 1 or 2, further comprising: and sealing two ends of the packer after the optical cable pre-penetrates the packer, and then carrying out a packer penetrating hole sealing pressure test.

4. A method of continuously running a downhole cable according to claim 3, further comprising skid mounting the packer, monitoring member, securing and running mechanism.

5. A method of continuous downhole wireline running according to claim 1, 2 or 4, further comprising: and the lower chassis drives the fixing and feeding mechanism to lower the packer and the monitoring piece.

6. A downhole wireline continuous-running apparatus for performing the method of any of claims 1 to 5, the apparatus comprising:

a drum configured to rotate the fiber optic cable down to the production well by rotation;

and the fixing and sending mechanism is configured to fix and adjust the packer and the monitoring piece to the required positions.

7. The apparatus of claim 6, wherein the fixing and feeding mechanism is a rotatable and extendable arm assembly, and the arm assembly comprises a lower arm portion and an upper arm portion, the lower arm portion and the upper arm portion are rotatably connected, the lower arm portion is connected to the lower turntable and can extend and retract, and the upper arm portion can drive the packer or the monitoring member to rotate by a certain angle.

8. The apparatus of claim 7, further comprising a lower plate configured to drive the setting and running mechanism to lower the packer and the monitoring element.

9. A downhole wireline continuous run in apparatus as described in claim 8, further comprising a skid mounted support within which the drum, securing and running mechanism, and lower chassis are skid mounted.

10. A downhole wireline continuous running apparatus according to claim 9, further comprising a sensor cartridge for mounting a fixed monitoring member and mechanically protecting the monitoring member mounted thereon during the downhole operation and during the downhole working operation; preferably, the device further comprises a depth recording mechanism, and the depth recording mechanism is used for reading the running depths of the optical cable, the packer and the monitoring element; preferably, the device further comprises a control system for controlling the running speed of the optical cable, the packer and the monitoring element; preferably, the apparatus further comprises a seal assembly for effecting a high pressure seal of the cable after it has traversed from the packer or from the wellhead.

Background

Accurate oil well parameters and reservoir dynamics are often required to be obtained in the ocean oil and gas exploitation process, and the intelligent well technology provides a more intelligent, more flexible and variable management mode for oil resources, is receiving more and more attention, and becomes an important technology of the oil industry in the 21 st century. In the whole production process, the intelligent well can be used for dynamic prediction of the production process through pressure, temperature, flow and other data obtained by the underground monitoring system, and has the great advantage of providing accurate and reliable information for oil deposit dynamic analysis and oil well production optimization control. However, the smart well is mostly used for the layered production of single well and multiple oil reservoirs or multilateral wells, and is a method for interpreting downhole pressure and temperature data while producing and testing (without shutting down the well and stopping pumping), and the interpretation method of the obtained downhole pressure and temperature data is different from the pressure and temperature interpretation of a conventional production well. Therefore, the effectiveness of collected data processing and the reasonability and accuracy of data interpretation directly relate to the success or failure of production optimization control of the intelligent well, and finally, the dynamic simulation and analysis results of the oil reservoir are influenced. The optical cable is used as a sensing and transmission channel of underground monitoring data and needs to be put into a production well along with an oil pipe, if a packer needs to be installed, the optical cable needs to penetrate through the packer, the optical cable needs to be cut off, the optical cable at the lower part penetrates through the packer to be installed and pressure tested, then fusion splicing operation is carried out on the optical cable and the optical cable at the upper part, optical signal loss possibly occurs at the breakpoint of the optical cable, the accuracy of the monitoring data and the service life of a monitoring system are influenced, the fusion splicing requirement of field operation is high, and the operation time is long.

Therefore, it is urgently needed to design a new technical scheme for continuously putting a simple and efficient underground optical cable and related monitoring sensors in combination with the difficulty of actual operation so as to solve the related problems caused by cutting and re-welding the optical cable.

Disclosure of Invention

In view of the above-mentioned deficiencies of the prior art, the present invention is directed to a method and apparatus for continuously lowering an optical cable downhole to overcome some or all of the deficiencies of the prior art.

The invention firstly provides a method for continuously putting down an underground optical cable, which comprises the following steps:

the optical cable penetrates through the packer and the monitoring part in advance, and is conveyed to the wellhead of the production well in a rotating mode through the rotating drum when the optical cable needs to be put into the production well; the packer and the monitoring piece are fixed and lowered to a required position through a fixing and feeding mechanism.

According to an embodiment of the invention, the method further comprises pre-connecting the optical cable with the monitoring element in advance; preferably, the method further comprises controlling the running speed of the optical cable, the packer and the monitoring element through a control system, and reading the running depth of the optical cable, the packer and the monitoring element through a depth recording mechanism.

According to an embodiment of the invention, the method further comprises: and sealing two ends of the packer after the optical cable pre-penetrates the packer, and then carrying out a packer penetrating hole sealing pressure test.

According to one embodiment of the invention, the method further comprises skid mounting the packer, monitoring element, securing and running mechanism.

According to an embodiment of the invention, the method further comprises: and the lower chassis drives the fixing and feeding mechanism to lower the packer and the monitoring piece.

The invention also provides a device for continuously descending the underground optical cable, which is used for executing the method for continuously descending the underground optical cable, and the device comprises:

a drum configured to lower the fiber optic cable to the wellhead by rotating;

and the fixing and sending mechanism is configured to fix and send the packer and the monitoring piece to a required position.

According to one embodiment of the invention, the fixing and feeding mechanism is a rotatable and extensible mechanical arm assembly, and comprises a lower mechanical arm part and an upper mechanical arm part, the lower mechanical arm part and the upper mechanical arm part are rotatably connected, the lower mechanical arm part is connected with the lower turntable and can extend and retract, and the upper mechanical arm part can drive the packer or the monitoring piece to rotate for a certain angle.

According to one embodiment of the invention, the device further comprises a lower chassis configured to drive the setting and running mechanism to lower the packer and the monitoring element.

According to an embodiment of the invention, the device further comprises a skid-mounted support, and the rotating drum, the fixing and feeding mechanism and the lower chassis are skid-mounted in the skid-mounted support.

According to one embodiment of the invention, the device further comprises a sensor support cylinder, which is used for installing and fixing the monitoring piece and mechanically protecting the monitoring piece installed on the sensor support cylinder during the process of going down the well and the process of working in the well; preferably, the device further comprises a depth recording mechanism, and the depth recording mechanism is used for reading the running depths of the optical cable, the packer and the monitoring element; preferably, the device further comprises a control system for controlling the running speed of the optical cable, the packer and the monitoring element; preferably, the apparatus further comprises a seal assembly for effecting a high pressure seal of the cable after it has traversed from the packer or from the wellhead.

The method and the device for continuously descending the underground optical cable can realize the continuous descending of the optical cables in different packer sections and monitoring devices such as optical fiber sensors and the like so as to avoid the shearing and fusion of the underground optical fiber, effectively reduce the error caused by optical signal loss due to splicing, improve the measurement precision of temperature and pressure parameters and the descending installation efficiency of the sensors and reduce the operation time.

Drawings

FIG. 1 is a schematic front view of a continuous drop device for an optical cable downhole according to an embodiment of the present invention;

FIG. 2 is a schematic top view of a device for continuously lowering a fiber optic cable downhole according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of a device for continuously running a fiber optic downhole cable to rotate a packer to an inclined direction at a wellhead according to an embodiment of the invention;

reference numerals:

1. a rotating drum; 2. a lower turntable; 3. a packer; 4. a sensor support cylinder; 5. a fixing and feeding mechanism; 6. an optical cable; 7. a support is skid-mounted; 8. the lower part of the mechanical arm; 9. the upper part of the mechanical arm; 10. a claw is provided.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the objects, features and advantages of the invention can be more clearly understood. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely intended to illustrate the spirit of the technical solution of the present invention.

Unless otherwise indicated, all references to up and down directions herein are to the same extent as the references to up and down directions in FIG. 1 shown in the present application and described herein.

The invention aims to provide a method and a device for continuously descending an underground optical cable, which can realize the continuous descending of optical cables in different packer sections and monitoring devices such as an optical fiber sensor and the like so as to avoid the shearing and fusion of the underground optical fiber, effectively reduce the error caused by the optical signal loss caused by the splicing, improve the measurement precision of temperature and pressure parameters and the descending installation efficiency of the sensor, reduce the operation time and record the descending depth of the optical cable.

The invention firstly provides a method for continuously putting down an underground optical cable, which comprises the following steps:

the optical cable penetrates through the packer and the monitoring part in advance, and when the optical cable needs to be put into the production well, the optical cable is rotationally put down to the wellhead of the production well through the rotary drum; the packer and the monitoring piece are fixed and lowered to a required position through a fixing and feeding mechanism.

The invention also provides a device for continuously descending the underground optical cable, which is used for executing the method for continuously descending the underground optical cable, and the device comprises:

a drum configured to rotate the fiber optic cable down to the production well;

and the fixing and sending mechanism is configured to fix and send the packer and the monitoring piece to a required position.

According to the technical scheme, the optical cable does not need to be cut off, but passes through equipment such as a packer in advance, and then the optical cable, the packer, a monitoring piece and the like are respectively lowered to the required depth, so that a different technical concept and solution are provided for monitoring the intelligent well through the underground monitoring system.

According to one embodiment of the invention, the device for continuously descending the underground optical cable mainly comprises a skid-mounted support, a rotary drum, a lower rotary table, a packer group, an optical fiber sensor support cylinder, a fixing and feeding mechanism, a descending length automatic reading mechanism, an oil pipe matching connecting tool and the like.

As shown in fig. 1 and 2, the rotary drum 1 is connected with the lower rotary disk 2 through a rotary piece, and the rotary drum 1 and the lower rotary disk 2 can rotate relatively. The control system installed in the device can control the rotating speed of the rotating drum 1 or the lower rotating drum 2 and read the length of the optical cable 6 to record the depth. The inner part of the packer 3 penetrates through the optical cable 6 in advance and is sealed, the packer is arranged in a skid-mounted support 7 of the continuous running device, the optical fiber sensor is fixed on the sensor support cylinder 4 in advance, is well connected with the optical cable 6, is sealed and is mechanically protected, and the optical fiber sensor is arranged in the skid-mounted support 7 of the device. And an optical cable 6 connected with the packer 3 and the sensor is wound on the rotary drum 1. The wound cable can be released by rotating the drum 1. When the required packer 3 or sensor is lowered to the designed depth, the fixing and sending mechanism 5 sends the packer or sensor to the wellhead. So can realize that different packer section optical cables and optical fiber sensor go into in succession, it has avoided the butt fusion of cutting of optical cable in the operation scene in the pit, can effectively reduce because of the optical signal loss that the butt fusion leads to, improve optical cable measurement accuracy in the pit, life to and the optical cable goes into installation effectiveness down, and processing is convenient, and investment cost is low, and application prospect is good.

The skid-mounted device is a form of integrally combining the device frame and the device, and a group of devices are fixed on the chassis and can be used after being moved integrally. Simply, each part of the unit is arranged on a large-scale integral base, namely skid-mounted installation. The whole transportation is enough during the transportation. The skid-mounted structure is convenient to transport, marine operation needs to be carried to a platform by a ship, and the skid-mounted structure is convenient to manufacture.

The embodiment solves the error problem caused by optical signal loss due to shearing and welding of the underground optical fiber, and improves the measurement precision of parameters such as temperature and pressure and the efficiency of sensor installation.

According to one embodiment of the invention, the drum 1 is light and is wrapped with armored cables, the lower turntable 2 is heavy as a chassis and is connected with the fixing and feeding mechanism 5, and the drum 1 and the lower turntable 2 are connected through a rotating bearing and can rotate relatively during the feeding process to release the cables wrapped on the drum. The cable 6 and packer 3 etc. may not be run downhole at the same time. The installation control system can control the rotational speed in the device, and possesses the optical cable length and reads the function, can take notes the concrete degree of depth of going into when the optical cable goes into in succession, can also guarantee to avoid the optical cable not receive too big moment of torsion and take place the performance impaired.

According to one embodiment of the invention, the seal assembly is used to effect a high pressure seal after the downhole armored cable has traversed the packer or from the wellhead. When the device is installed, the underground armored optical cable penetrates through the packer 3, the sealing components used at two ends of the packer 3 are installed on the underground armored optical cable, then the sealing components are installed at NPT threads at two ends of the packer, the penetrating positions have mechanical protection design, and sealing pressure test of penetrating holes is completed. For example, the cable through hole is designed to pass through the cable with a cross section of 11mm x 11mm, the outer package is removed at the seal, and the sealing ferrule of the sealing assembly is designed to have a connection caliber of 1/4 ″.

According to one embodiment of the invention, the sensor support cylinder 4 is used for installing and fixing a downhole optical fiber sensor and plays a role of mechanical protection for the optical fiber sensor installed on the sensor support cylinder in the downhole process and the downhole working process, the sensor support cylinder 4 can be a tubular fixing device, produced oil gas can flow inside the sensor support cylinder, a groove is formed in the outer wall of the sensor support cylinder, the sensor support cylinder can be used for placing the sensor in the groove and can be clamped and fixed in the circumferential direction through a clamping jaw, and a cover can cover the sensor outside the groove to protect the sensor. The sensor support cylinder 4 can be connected with an oil pipe up and down. The front and the back of the sensor can be connected with the optical cable.

During installation, the optical cable and the optical fiber sensor are connected in advance, and the optical fiber sensor can be fixed by the sensor support cylinder 4, so that relative rotation and relative movement between the armored optical cable and the sensor in a well descending process are prevented, and the safety and reliability of signal transmission of the sensor are guaranteed.

According to one embodiment of the invention, the fixing and feeding mechanism 5 is connected to the body of the lower rotary table 2 and serves as a fixing mechanism for placing the packers and sensor cartridges to be fed in when not in operation, and the number of sets can be adjusted according to the number of the packers and sensor cartridges required in practice. When the running operation is needed, the packer or the sensor can be sent to the wellhead as a mechanical sending mechanism.

Specifically, the fixing and feeding mechanism 5 is a rotatable and extensible mechanical arm assembly and mainly comprises a lower mechanical arm part 8 and an upper mechanical arm part 9, the lower mechanical arm part 8 is rotatably connected with the upper mechanical arm part 9, the lower mechanical arm part 8 is connected with the lower rotary table 2, and the upper mechanical arm part 9 can be matched with the connecting claw 10 to fix the packer 3 or the monitoring part and can drive the packer 3 or the monitoring part to rotate for a certain angle. When the packer or monitoring part is used, the packer or monitoring part is fixed on the lower base plate, the periphery of the optical cable rotary drum is provided, the optical cable is penetrated in advance, when the packer or monitoring part is required to be put down, the lower base plate 2 rotates to drive the lower part 8 of the mechanical arm to rotate, so that the packer or monitoring part to be put down rotates to the direction of a wellhead, the lower part 8 of the mechanical arm radially extends along the direction of the wellhead, the upper part 9 of the mechanical arm inclines towards the direction of the wellhead (the inclination angle is not more than 45 degrees), the packer is lifted from the fixing and feeding mechanism 5 by matching with a lifting appliance, the lifting appliance is put down into the wellhead, and therefore the operation of sending the packer or monitoring part to the wellhead can be achieved.

The optical cable is used for transmitting underground monitoring data optical signals, and in consideration of the fact that the optical fiber is damaged due to possible accidents in construction and long-period operation processes of the intelligent well, multi-core spare optical fibers are specially designed, for example, each spare 2-core optical fiber of a distribution sensor assembly selects a multi-core single-mode optical fiber armored optical cable, the outer diameter of a metal armor of the optical cable is 1/4 ″, and the outer part of the metal armor of the optical cable is 11mm × 11mm for protection and encapsulation. During installation of the underground optical cable, the underground optical cable needs to pass through a wellhead device and various stratum packers, and suspension installation and protection outside a tubing string and an underground ICV string need to be realized.

According to one embodiment of the invention, the depth recording mechanism can record the running depth of an optical cable, a packer and the like in real time during the running process.

All mechanisms and elements related to the above can be integrated in the skid-mounted support 7, so that the offshore transportation and platform hoisting are facilitated, and the continuous lowering system is protected.

Supporting oil pipe connecting means for being connected of packer and oil pipe, screw thread opposite direction about the connecting means, for example, it is used for connecting the packer to go up the screw thread, and lower screw thread is used for connecting oil pipe, can realize under the not pivoted condition of packer and oil pipe, only rotates supporting connecting means and can realize being connected of packer and oil pipe, satisfies the requirement of the torque of detaining on.

The invention can realize the continuous running of the underground optical cable through the following specific embodiments:

a continuous descending device for underground optical cables comprises the following use steps:

s1: pre-connecting an optical cable and an optical fiber sensor in a factory to pre-penetrate and seal the packer by the optical cable, and then performing a packer penetrating hole sealing pressure test;

s2: skid-mounting the device to a specified position of a platform wellhead;

s3: during operation, the first group of sensor supporting cylinders are conveyed to a wellhead through a conveying mechanism at the wellhead of the platform and are connected with an oil pipe;

s4: rotating the rotary drum to release the optical cable along with the running-in process, ensuring the stress of the optical cable to be constant, recording the running-in depth, and sending the packer and the sensor support cylinder to a wellhead through a fixing and sending mechanism at the wellhead of the platform when the specified depth is reached;

s5: and repeating the steps to realize continuous running of the optical cable without cutting off the optical cable on site.

It should be noted that, in this document, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention; relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

In addition, in the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The foregoing embodiments are merely illustrative of the present invention, and various components and devices of the embodiments may be changed or eliminated as desired, not all components shown in the drawings are necessarily required, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments described herein, and all equivalent changes and modifications based on the technical solutions of the present invention should not be excluded from the scope of the present invention.