Downhole television logging process method for quantitative analysis

Abstract

The invention discloses an underground television logging process method for quantitative analysis, which comprises the following steps of: 1, placing and mounting coiled tubing operation equipment, testing a four-ram blowout preventer, performing coiled tubing penetration operation, assembling a well control device, and mounting a connector at the tail end of a coiled tubing; 2, a well dredging and flushing tool string is installed at the tail end of the connector, and a well control device is connected with a well mouth device; 3, a continuous pipe is put into the well to conduct well washing operation; 4, after well washing is completed, the well control device and the well mouth device are disconnected, the continuous pipe is pulled out, and a well logging tool string with an underground camera is installed at the tail end of the continuous pipe; 5, the well control device is connected with the well head device, and a well logging tool string is put into the well to conduct underground upper measurement and lower measurement operation; 6, the well control device is detached from the well head device, the continuous pipe is pulled out, and the well logging tool string is detached; the well shaft can be kept clean, the operation efficiency is improved, and repeated operation caused by too fuzzy pictures after well logging is completed is avoided.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of well logging, and particularly relates to a downhole television logging process method for quantitative analysis. BACKGROUND

[0002] Large-scale, high-sand ratio, strong temporary plugging and other fracturing technologies are currently applied to the process of shale gas development, but the transformation effect is generally poor, and the single well EUR production does not reach the planning level, so post-fracturing evaluation technology needs to be used to evaluate the transformation effect to provide a basis for repeated transformation. The post-fracturing evaluation technology commonly used at present includes direct diagnosis technology and indirect diagnosis technology, the former includes downhole television, microseismic measurement, radioactive tracer, well temperature test, surface and bottom hole inclinometer and the like (a series of methods for fracture monitoring), and the main feature is high cost and intuitive results; the indirect measurement includes real-time monitoring and interpretation of fracturing, post-fracturing pressure drop analysis, well test analysis, production history matching and the like, and the main feature is relatively low cost but complex technology.

[0003] The post-fracturing evaluation technology based on downhole television is based on the following principle: a downhole camera is lowered into the well to obtain dynamic / static images in the well, image processing technology is used to enhance, split, transform and extract the obtained image data, and finally the geometric data of the perforation on the casing wall is obtained, including area, shape, perimeter and the like, and according to the positive relationship between the perforation geometric shape and area and the perforation sand amount, the transformation effect of the well, section and cluster can be evaluated.

[0004] Currently available coiled tubing downhole television logging techniques include document number CN111022038A, "A Nitrogen Lift Downhole Visual Casing Breach Water Point Monitoring Method." The method disclosed involves injecting nitrogen into the annulus to reduce wellbore pressure, allowing formation gas at the casing breach point to enter the wellbore. Downhole television monitoring allows for real-time visualization of gas leakage, identifying the casing breach location. Before entering the well, the wellbore is flushed until the clarity of the inflow and outflow fluids is consistent before running the tool to ensure effective downhole television logging. Document number CN115387783A, "A Comprehensive Leak Detection Method for Coiled Tubing Horizontal Wells," discloses a method that includes using a coiled tubing flushing tool to flush and salvage debris within the wellbore. A splitter is used to seal the annulus and inject pressure, combined with a dichotomy method, to initially determine the casing leak location. The wellbore is then flushed until the clarity of the return fluid at the wellhead is consistent with that of the pumped fluid. Finally, a downhole television tool is run through the coiled tubing to log the casing leak interval and confirm the extent of the leak. The above methods all use continuous tubing and downhole television logging technology to assist conventional operations. In both methods, the wellbore is flushed before the downhole television tool is put into the well to ensure the clarity of the downhole television video image. The standard for the successful flushing operation is that the clarity of the inflowing fluid and the outflowing fluid are consistent. This flushing method has low operating difficulty, but has great limitations. It cannot guarantee that the wellbore clarity will be maintained at a high level for a long time under sand production and oil well conditions. Therefore, it is not suitable for post-pressure evaluation technology based on downhole television with long logging time. Summary of the Invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a downhole television logging process method that can maintain high clarity for a long time under sand and oil well conditions and can be used for quantitative analysis.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows: A downhole television logging process for quantitative analysis comprises the following steps:

[0007] Step 1: First, place and install the coiled tubing equipment and test the opening and closing functions of the four-ram BOP. Then, perform the coiled tubing threading operation, assemble the well control device, and install the connector at the end of the coiled tubing. Finally, perform the tensile load and pressure resistance tests on the connector.

[0008] Step 2: After the load and pressure tests in step 1 are passed, install the well cleaning tool string at the end of the connector, connect the well control device to the wellhead device, and conduct an overall pressure test;

[0009] Step 3: After the pressure test is passed in step 2, the coiled tubing is lowered into the well to perform well cleaning operations;

[0010] Step 4: after the well washing is completed, disconnect the well control device from the wellhead device, pull out the coiled tubing, and install the logging tool string with the downhole camera at the end of the coiled tubing;

[0011] Step 5: connect the well control device with the wellhead device, pump clean water into the coiled tubing to test the pressure of the logging tool string, and after the pressure test is qualified, lower the logging tool string into the well to perform the uphole and downhole logging operation;

[0012] Step 6: disconnect the well control device from the wellhead device, pull out the coiled tubing, and disassemble the logging tool string, download and view the logging data.

[0013] The beneficial effects of the above technical solution are that the well washing is performed in advance, the clarity is higher when the imaging detection is performed in the well later, the wellbore can be kept clean, the operation efficiency is improved, and the repeated operation caused by too blurred picture after the logging is completed is avoided.

[0014] The specific operation of the opening and closing function test of the four-blade blowout preventer in step 1 in the above technical solution is to connect the four-blade blowout preventer with the hydraulic station first, then test whether each blade of the four-blade blowout preventer can be normally opened and closed under the hydraulic drive, open each blade of the four-blade blowout preventer to the full open state after the test is qualified, perform the coiled tubing pipe-through operation, connect the injection head, the blowout preventer box, the blowout preventer pipe and the four-blade blowout preventer in sequence to complete the assembly of the well control device after the pipe-through operation is completed, and then install the connector at the end of the coiled tubing.

[0015] The beneficial effects of the above technical solution are that the opening and closing function of the four-blade blowout preventer is tested in advance, so that it can be ensured that it can normally operate in an emergency, and the connector provided at the end of the coiled tubing is connected with the well washing tool string or the logging tool string later.

[0016] The specific operation of the pull load and pressure resistance test of the connector in step 1 in the above technical solution is to install a pull / pressure test disc at the end of the connector, the pull load experiment is to lift the coiled tubing by using the self pulling force of the injection head, and the pressure resistance test is to close the pressure relief valve on the pull / pressure test disc and pump clean water into the coiled tubing.

[0017] The beneficial effects of the above technical solution are that the pull load and pressure resistance test can ensure that the connector is firmly installed at the end of the coiled tubing.

[0018] In the pull load test process in the above technical solution, the pulling force of the injection head is slowly increased, and the step pull load is 20t, after each test, it is checked whether the connector slips, and if the total slip amount is not more than mm, the installation of the connector is qualified, otherwise the connector needs to be reinstalled.

[0019] The beneficial effects of the above technical solution are that the operation is simple, and the pull load test requirement is strict.

[0020] The first single-flow valve, the first release hand, and the flushing head are sequentially connected from top to bottom in the step 2 of the technical solution, the wellhead main valve of the blowout preventer and the wellhead device are closed for the whole pressure test, and the liquid injection port of the wellhead device is used to inject liquid for pressure test operation.

[0021] The technical solution has the beneficial effect of simple structure.

[0022] The pressure test in the step 1, the whole pressure test in the step 2, and the pressure test operation in the step 5 are gradually increased to 60 MPa by 10%, 50%, and 100%, respectively, and the pressure drop is less than 0.7 MPa for 10 minutes of stable pressure.

[0023] The technical solution has the beneficial effect of strict pressure test standard, which can ensure good sealing of the connector at the end of the coiled tubing, and good sealing of the through-washing tool string and the logging tool string at the end of the connector.

[0024] The specific steps of the well washing operation in the step 3 are as follows: the wellhead main valve of the wellhead device is opened, the coiled tubing is lowered into the well, the pump is started to circulate and degas after the coiled tubing is lowered to the build-up point, the fluid circulation is maintained after the circulation and degassing is completed, the coiled tubing is continuously lowered to the bottom of the logging section, the fluid circulation is performed at the fixed point at the bottom of the logging section, the coiled tubing is pulled out after the ground return fluid meets the construction requirements, the wellhead is flushed at a large flow rate, then the pump is stopped and the through-washing tool string is pulled out into the blowout pipe, and the wellhead main valve is closed.

[0025] The technical solution has the beneficial effect of good well washing effect, and the well is in a clean water environment after well washing treatment, which is beneficial to subsequent visual logging.

[0026] The logging tool string is sequentially connected from top to bottom in the technical solution, and includes a second single-flow valve, a second release hand, a circulation short section, a conversion joint, a first spring centralizer, a battery short section, a second spring centralizer, a storage communication short section, and a downhole camera.

[0027] The technical solution has the beneficial effect that the entire logging tool string can operate independently, can store data in real time, and can be kept centered in the well by the two spring centralizers.

[0028] The well control device, the coiled tubing operation equipment and the wellhead device are connected, and the wellhead main valve is opened to continue the logging tool string into the well for logging operation.

[0029] The beneficial effects of the above technical scheme are that the logging camera is first lowered into the well for 15m to test the cleanliness of the well, and when the cleanliness of the well meets the needs of visual detection, the logging camera can be formally lowered into the well for detection again, and if it does not meet the requirements, the well is washed again until the needs are met.

[0030] In the step 5 of the above technical scheme, when the logging tool string is performing logging operation, the logging tool string is slowly lowered into the well, and clean water is injected into the well through the wellhead device and the coiled tubing, the clean water injection and discharge capacity of the wellhead device is 300-400L / min, the pump injection capacity in the coiled tubing is 200-300L / min, the lens is flushed for 5min after reaching the top of the logging section, and then the lowering speed is reduced until the bottom of the logging section is reached and the logging operation is completed.

[0031] The beneficial effects of the above technical scheme are that clean water can be continuously injected into the well for well washing while the well is visually tested, so that the well can be kept in a clear state, and the operation time of the downhole camera in the well can be prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a docking schematic view of the well control device and the coiled tubing operation equipment in the embodiment of the present application.

[0033] Figure 2 It is a structural schematic view of the wellhead device and the coiled tubing in the well in the embodiment of the present application.

[0034] Figure 3 It is a structural schematic view of the well control device and the variable diameter joint in the embodiment of the present application.

[0035] Figure 4 It is a structural schematic view of the variable diameter joint and the pulling / pressure testing disc in the embodiment of the present application.

[0036] Figure 5 It is a structural schematic view of the well washing tool string in the embodiment of the present application.

[0037] Figure 6Schematic diagram of the structure of the logging tool string in an embodiment of the present invention.

[0038] Figure: 1. Well control unit; 11. Injection head; 12. BOP; 13. Lubricant pipe; 14. Four-gate blowout preventer; 2. Coiled tubing equipment; 21. Coiled tubing; 22. Connector; 23. Hose reel; 3. Well cleaning tool string; 31. First check valve; 32. First release handle; 33. Flushing head; 4. Wellhead assembly; 41. Wellhead main valve; 42. Injection port; 43. Mud outlet; 5. Well logging Tool string; 51. Second check valve; 52. Second release handle; 53. Circulation nipple; 54. Adapter; 55a. First spring centralizer; 56. Battery nipple; 55b. Second spring centralizer; 57. Storage and communication nipple; 58. Downhole camera; 6. Test pull / test pressure plate; 7. Reducer; 8a. Bottom of logging section; 8b. Top of logging section; 91. Pump truck; 92. Water tank; 93. Mud tank. DETAILED DESCRIPTION

[0039] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention. The following paragraphs describe the present invention in more detail by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the drawings are all in a very simplified form and are not in exact proportions. They are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention.

[0040] like Figures 1-6 As shown, this embodiment provides a downhole television logging process method for quantitative analysis, comprising the following steps:

[0041] Step 1: First, place and install the coiled tubing equipment 2 (must comply with recommended practices for coiled tubing operations in oil and gas wells) and test the opening and closing functions of the four-ram blowout preventer 14. Then, thread the coiled tubing 21, assemble the well control unit 1, and install the connector 22 at the end of the coiled tubing 21. Then, perform a load and pressure test on the connector 22 (only proceed to the next step after the load and pressure tests are passed; otherwise, reinstallation is required).

[0042] Step 2: After the load and pressure tests in step 1 are passed, the well cleaning tool string 3 is installed at the end of the connector 22, and the well control device 1 is connected to the wellhead device 4 for an overall pressure test (the next step can only be carried out after the overall pressure test is passed; otherwise, reinstallation is required);

[0043] Step 3: After the pressure test in step 2 is passed, the coiled tubing 21 is lowered into the well to perform well cleaning operations;

[0044] Step 4: After the well washing is completed, disconnect the well control device 1 from the wellhead device 4, pull out the coiled tubing 21, and install the logging tool string 5 with the downhole camera 58 at the end of the coiled tubing 21;

[0045] Step 5: Connect the well control device 1 with the wellhead device 4, pump clean water into the coiled tubing 21 to test the pressure of the logging tool string 5 (if the pressure test is qualified, the next step can be performed, otherwise it needs to be reinstalled), and after the pressure test is qualified, lower the logging tool string 5 into the well to perform the uphole and downhole logging operations;

[0046] Step 6: Disconnect the well control device 1 from the wellhead device 4, pull out the coiled tubing 21, and disassemble the logging tool string 5, download and view the logging data. By pre-washing the well, the clarity of the imaging detection in the well can be higher, and the wellbore can be kept clean, improving the operation efficiency and avoiding repeated operations due to too blurred pictures after logging.

[0047] The specific operation of the opening and closing function test of the four-blade blowout preventer 14 in step 1 of the above technical solution is to first connect the four-blade blowout preventer 14 with the hydraulic station, then test whether each blade of the four-blade blowout preventer 14 can normally open and close under hydraulic drive, open each blade of the four-blade blowout preventer 14 to the fully open state after the test is qualified, and perform the coiled tubing 21 threading operation, then sequentially connect the injection head 11, the blowout preventer box 12, the blowout preventer pipe 13, and the four-blade blowout preventer 14 to complete the assembly of the well control device 1, and then install the connector 22 at the end of the coiled tubing 21. By pre-testing the opening and closing function of the four-blade blowout preventer, it can be ensured that it can normally operate in an emergency. The connector provided at the end of the coiled tubing is connected with the washing or logging tool string in the later stage.

[0048] The specific operation of the connector 22 for load pulling and pressure resistance test in step 1 of the above technical solution is to install a pull / pressure test disc 6 at the end of the connector 22. The load pulling experiment is to use the self-pulling force of the injection head 11 to lift the coiled tubing 21, and the pressure resistance test is to close the pressure relief valve on the pull / pressure test disc 6 and pump clean water into the coiled tubing 21. If the load pulling and pressure resistance tests can ensure that the connector is firmly installed at the end of the coiled tubing.

[0049] In the load pulling test process of the above technical solution, the pulling force of the injection head 11 is slowly increased, and the load pulling is stepped to 20t. After each test, it is checked whether the connector 22 slips, and if the total slip amount is not more than 5mm, the connector 22 is installed qualified, otherwise the connector 22 needs to be reinstalled. The operation is simple, and the load pulling test is strict.

[0050] The first single-flow valve 31, the first release 32 and the flushing head 33 are sequentially connected from top to bottom in the well washing tool string 3 in step 2, the whole pressure test in step 2 is to close the blowout preventer 12 and the wellhead main valve 41 of the wellhead device 4, and the liquid injection through the liquid injection port 42 of the wellhead device 4 is used to perform the pressure test operation, and the structure is simple.

[0051] The pressure test in step 1, the whole pressure test in step 2 and the pressure test operation in step 5 are all gradually increased to 60 MPa by 10%, 50% and 100% of the pump pressure, and the pressure is stabilized for 10 minutes, and the pressure drop is less than 0.7 MPa, which is qualified, the pressure test standard is strict, and the sealing performance of the connector installed at the end of the coiled tubing can be ensured, and the sealing performance of the well washing tool string and the logging tool string installed at the end of the connector can be ensured.

[0052] The specific steps of the well washing operation in step 3 are as follows: the wellhead main valve 41 of the wellhead device 4 is opened, the coiled tubing 21 is lowered into the well, the pump is started to circulate and degas after the coiled tubing 21 is lowered to the build-up point, the fluid circulation is maintained after the circulation and degassing is completed, the coiled tubing 21 is continuously lowered to the bottom 8a of the logging section, the fluid circulation is performed at the fixed point of the bottom 8a of the logging section, the coiled tubing 21 is started to be pulled out when the ground return liquid meets the construction requirements, and the well washing tool string 3 is pulled out to the blowout preventer 13 after a large amount of flushing at the wellhead, and the wellhead main valve 41 is closed, the well washing effect is good, and the well is in a clean water environment after the well washing treatment, which is beneficial to subsequent visual logging.

[0053] The depth counter on the coiled tubing needs to be cleared during the well washing operation in step 3, and the position of the well washing tool string 3 at the time of clearing is recorded, then the coiled tubing is lowered, the speed through the wellhead is <5 m / min, the speed in the straight section is controlled within 20 m / min, and the coiled tubing is tested every 500 m. After the coiled tubing is lowered to the build-up point, the pump is started to circulate and degas, the ground uses a choke pressure control to spray after the pump is started to circulate, the wellhead back pressure and the shut-in pressure are basically consistent, the coiled tubing is intermittently moved up and down during the circulation and degassing, the coiled tubing is continuously lowered to 100 m below the bottom 8a of the logging section after the circulation and degassing is completed, and the position of the coiled tubing is marked, the coiled tubing is continuously circulated to the ground return liquid with a turbidity of less than 10 NTU, and then the coiled tubing is started to be pulled out, and the channel between the wellhead device (the wellhead device is a liquid discharge cross) and the blowout preventer is repeatedly flushed with a large amount of liquid for 2-3 times.

[0054] The logging tool string 5 from top to bottom is respectively a second single valve 51, a second releasing valve 52, a circulating short section 53, a conversion joint 54, a first spring centralizer 55a, a battery short section 56, a second spring centralizer 55b, a storage communication short section 57 and a downhole camera 58, so that the whole logging tool string can run independently, and the data can be stored in real time, and the logging tool string can be kept centered in the well through the two spring centralizers.

[0055] In step 5, after the pressure test is qualified, the wellhead main valve 41 is slowly opened, and the logging tool string 5 is lowered into the well, and is retracted into the blowout preventer 13 after entering the well for 15 m, and the wellhead main valve 41 is closed, the variable diameter joint 7 is disconnected with the wellhead device 4, and the logging tool string 5 is extended downward to outside the well control device 1 to visually observe the downhole camera 58, if there is no grease on the downhole camera 58, the variable diameter joint 7 and the wellhead device 4 are connected, and the wellhead main valve 41 is opened to continue to lower the logging tool string 5 into the well for logging operation; if the downhole camera 58 is not clean, step 3 is performed, the logging camera is first lowered into the well for 15 m to test the cleanliness of the well, when the cleanliness of the well meets the needs of visual detection, the downhole camera can be formally lowered into the well for detection again, if it does not meet the requirements, the well is washed again until the needs are met.

[0056] In step 5, when the logging tool string 5 is performing logging operation, the logging tool string 5 is slowly lowered into the well, and clean water is injected into the well through the wellhead device 4 and the coiled tubing 21, the clean water injection and discharge capacity of the wellhead device 4 is 300-400 L / min, the pump injection capacity in the coiled tubing 21 is 200-300 L / min, the lens is flushed for 5 min after reaching the top 8b of the logging section, then the lowering speed is reduced until the bottom 8a of the logging section is reached and the logging operation is completed, when the coiled tubing 21 reaches the marked position, the coiled tubing 21 is pulled up to the top 8b of the logging section to complete the uplogging operation, so that the clean water can be continuously injected into the well during the visual testing in the well to ensure that the well is in a clear state, which can prolong the operation time of the downhole camera in the well.

[0057] In step 5, the surface of the downhole camera needs to be coated with an active agent, and the time and depth information of the downhole camera and the coiled tubing equipment are synchronized, and the starting time of the logging tool string 5 is set according to the estimated time required for the logging tool string 5 to reach the top of the logging section.

[0058] The coiled tubing operation equipment 2 in the embodiment further comprises a pipe winding drum 23 for winding or unwinding the coiled tubing outside the well control device, and further comprises a water pool 92, a mud pool 93 and two pump trucks 91, the water inlets of the two pump trucks are communicated with the water pool, the water outlet of one of the pump trucks is communicated with the first section of the coiled tubing, so as to pump clean water into the coiled tubing, the water outlet of the other pump truck is communicated with the liquid injection port of the well head device, so as to pump clean water into the well, and the mud outlet of the well head device is communicated with the mud pool.

[0059] As shown in Figure 4 The connector in the embodiment can install the reducing joint 7 at the lower end of the four-blade blowout preventer 14 in advance before the tension test and the pressure test, at this time, the coiled tubing can be driven upward by the power of the injection head 11 to abut against the lower end of the reducing joint on the tension test / pressure test disc, and the corresponding test can be carried out.

[0060] The second single-flow valve 51 and the second releasing hand 52 in the logging tool string in the embodiment can be shared with the first single-flow valve 31 and the first releasing hand 32 in the well washing tool string.

[0061] After the video quality is confirmed to meet the requirements in the step 6, the operation is ended, and the video data depth correction operation is carried out, and after completion, the logging data is submitted, specifically, the depth correction method is that when the short sleeve lower end collar appears to the video central position, the length of the short sleeve is taken as the depth at this time, the time point is an initial time point, and then the depth of each time point is the length of the short sleeve plus the depth difference value corresponding to the current time and the initial time point on the continuous tubing depth time axis.

[0062] It should be noted that the above detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0063] It should be noted that the terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and furthermore, it should be understood that when the terms "comprise" and / or "include" are used in the specification, there is a feature, step, operation, device, component and / or combination thereof.

[0064] It has to be noted that the terms "first", "second", etc. as used in the description and the claims and the above figures of the present application are used to describe different objects, not to describe a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and embodiments of the application described herein are capable of operating in other sequences than the one described or other than suggested by the above text.

[0065] Also, the use of "adapted to", "configured to", "arranged to", "capable of" or "configured for" herein is meant to open up the possibility that the object in question is not only "adapted to", "configured to", "arranged to", "capable of" or "configured for" the specific purpose stated, but is also "adapted to", "configured to", "arranged to", "capable of" or "configured for" some other purpose or purposes.

[0066] Furthermore, the terms "comprise" and "comprising" and any variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of steps or units does not necessarily comprise only those steps or units but can include other steps or units not expressly listed or inherent to such process, method, article, or apparatus.

[0067] For the purposes of the description, a spatial relative term, such as "above", "below", "top", "bottom", and the like, can be used herein for ease of description to describe one device or feature's spatial position relation to another device or feature as illustrated in the figures. It is to be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures.

[0068] For example, if a device in the figures is turned over, elements described as "above" other elements or "below" other elements will then be oriented "below" other elements or "above" other elements. Accordingly, the exemplary term "above" can encompass both an orientation of above and below. The devices can be oriented in other ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0069] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application in any form; any person skilled in the art can easily implement the present application according to the drawings and the above description; however, any person skilled in the art can make some changes, modifications and equivalent changes of the above disclosed technical contents without departing from the technical solution of the present application, and the equivalent embodiments of the present application are still within the protection scope of the present application.

Claims

1. A process method for quantitative analysis of downhole video logging, characterized by, The method comprises the following steps: Step 1: first, place and install the coiled tubing operation equipment (2), and test the opening and closing function of the four-blade blowout preventer (14), then perform the coiled tubing (21) threading operation, assemble the well control device (1), and install the connector (22) at the end of the coiled tubing (21), and then perform the load test and pressure test on the connector (22); Step 2: after the load test and pressure test in step 1 are qualified, install the well flushing tool string (3) at the end of the connector (22), connect the well control device (1) with the wellhead device (4), and perform the overall pressure test; Step 3: after the pressure test in step 2 is qualified, lower the coiled tubing (21) into the well to perform the well flushing operation; Step 4: after the well flushing is completed, disconnect the well control device (1) from the wellhead device (4), pull out the coiled tubing (21), and install the logging tool string (5) with the downhole camera (58) at the end of the coiled tubing (21); Step 5: connect the well control device (1) with the wellhead device (4), pump clean water into the coiled tubing (21) to perform the pressure test on the logging tool string (5), and after the pressure test is qualified, lower the logging tool string (5) into the well to perform the uphole and downhole logging operation; Step 6: disconnect the well control device (1) from the wellhead device (4), pull out the coiled tubing (21), disassemble the logging tool string (5), and download and view the logging data.

2. The process method of downhole video logging for quantitative analysis of claim 1, wherein, The specific operation of the opening and closing function test of the four-blade blowout preventer (14) in step 1 is to first connect the four-blade blowout preventer (14) with the hydraulic station, then test whether each blade of the four-blade blowout preventer (14) can normally open and close under hydraulic drive, after the test is qualified, open each blade of the four-blade blowout preventer (14) to the fully open state, perform the coiled tubing (21) threading operation, after the threading is completed, sequentially connect the injection head (11), the blowout preventer box (12), the blowout preventer pipe (13) and the four-blade blowout preventer (14) to complete the assembly of the well control device (1), and then install the connector (22) at the end of the coiled tubing (21).

3. The process method of downhole video logging for quantitative analysis of claim 1, wherein, The specific operation of the load test and pressure test of the connector (22) in step 1 is to install the load test / pressure test disc (6) at the end of the connector (22), the load test is to lift the coiled tubing (21) by using the self-lifting force of the injection head (11), and the pressure test is to close the pressure relief valve on the load test / pressure test disc (6) and pump clean water into the coiled tubing (21).

4. The process method of downhole video logging for quantitative analysis according to claim 3, characterized in that, During the load test, the lifting force of the injection head (11) is slowly increased, and the step load test is performed to 20t, after each test, check whether the connector (22) slips, and if the total slip amount is not more than 5mm, the connector (22) is qualified, otherwise the connector (22) needs to be reinstalled.

5. The process method of downhole video logging for quantitative analysis of claim 1, wherein, The well flushing tool string (3) in step 2 is sequentially connected from top to bottom by the first check valve (31), the first release (32) and the flushing head (33), and the overall pressure test in step 2 is to close the wellhead main valve (41) of the blowout preventer box (12) and the wellhead device (4), and to perform the pressure test by injecting liquid through the liquid injection port (42) of the wellhead device (4).

6. The process method of downhole video logging for quantitative analysis of claim 5, wherein, The step 1 pressure test, the step 2 overall pressure test and the step 5 pressure test are all gradually increased to 60 MPa by 10%, 50% and 100% of the pump pressure, and the pressure is stable for 10 min, and the pressure drop is less than 0.7 MPa.

7. The process method of downhole video logging for quantitative analysis of claim 1, wherein, The specific steps of the step 3 well washing operation are: opening the wellhead main valve (41) of the wellhead device (4), lowering the coiled tubing (21) into the well, and pumping and circulating degassing after the coiled tubing (21) is lowered to the build-up point, and then keeping fluid circulation, and continuing to lower the coiled tubing (21) to the logging section bottom (8a), and performing fluid circulation at the logging section bottom (8a), and then starting to pull out the coiled tubing (21) when the ground backflow liquid meets the construction requirements, and then flushing at a large flow rate at the wellhead, and then stopping the pump and pulling out the well washing tool string (3) into the blowout preventer (13), and closing the wellhead main valve (41).

8. The process method of downhole video logging for quantitative analysis of claim 1, wherein, The logging tool string (5) is composed of a second check valve (51), a second release (52), a circulating short section (53), a conversion joint (54), a first spring centralizer (55a), a battery short section (56), a second spring centralizer (55b), a storage communication short section (57) and a downhole camera (58) from top to bottom.

9. The process method of downhole video logging for quantitative analysis of claim 1, wherein, After the step 5 pressure test is qualified, the wellhead main valve (41) is slowly opened, and the logging tool string (5) is lowered into the well, and then it is retreated into the blowout preventer (13) after 15 m, and the wellhead main valve (41) is closed, the variable diameter joint (7) is disconnected from the wellhead device (4), and the logging tool string (5) is extended downward to outside the well control device (1) to visually observe the downhole camera (58), if the downhole camera (58) is not clean, the variable diameter joint (7) and the wellhead device (4) are connected, and the wellhead main valve (41) is opened to continue to lower the logging tool string (5) into the well for logging operation; if the downhole camera (58) is not clean, the step 3 is performed.

10. The process method of downhole video logging for quantitative analysis of claim 9, wherein, When the logging tool string (5) is performing logging operation in the step 5, the logging tool string (5) is slowly lowered, and at the same time, clean water is injected into the well through the wellhead device (4) and the coiled tubing (21), the clean water injection and discharge capacity of the wellhead device (4) is 300-400 L / min, the pump injection capacity in the coiled tubing (21) is 200-300 L / min, the lens is flushed for 5 min after being lowered to the logging section top (8b), and then the lowering speed is reduced until the logging section bottom (8a) is reached and the logging operation is completed, and when the coiled tubing (21) reaches the marked position, the coiled tubing (21) is pulled up to the logging section top (8b) to complete the uplogging operation.

Images