A high-expanded-diameter umbrella-shaped supporting tool for layer selection and water plugging process string and its usage method

Abstract

The present invention provides a high-expansion umbrella-shaped support tool for layer selection water plugging process string and its usage method. The tail end of the coiled tubing is connected to the head end of the motor head assembly through a coiled tubing joint. The tail end of the motor head assembly is connected to the head end of the permanent plugging agent injection nipple. The tail end of the permanent plugging agent injection nipple is connected to the head end of the high-expansion umbrella-shaped support tool through a high-viscosity and high-strength temporary plugging agent injection nipple. The high-expansion umbrella-shaped support tool is connected to the head end of the mechanical coupling locator, and the tail end of the mechanical coupling locator is connected to the head end of the guide head. The present invention connects the high-expansion support tool through the coiled tubing, passes through the conventional tubing, and realizes the interlayer isolation of the producing layers by temporarily plugging with the high-viscosity and high-strength temporary plugging agent in the large-diameter casing, then pumps in the permanent plugging agent to realize the plugging of the high-water-producing layer, and finally realizes the purpose of controlling water production and increasing oil and gas production in the oil and gas well.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas development, and more specifically to a layer selection water plugging process string of a high-expanded umbrella-shaped support tool and its usage method. Background Art

[0002] In the later production stage of an oil and gas production well, after the completion string is run in, some water-producing layers have a large water production volume, which seriously affects the normal production of oil and gas. The oil and gas production will be significantly reduced. Therefore, it is necessary to plug the severely water-producing layers to reduce the water content of oil and gas and the formation backpressure, and improve the production of oil and gas wells.

[0003] In some existing oil and gas production wells, a combination of small-diameter upper and large-diameter lower casing is used for cementing (such as: 7" casing in the upper part and 9-5" / 8 casing at the tail). The problem of later water plugging is not considered during the completion stage. Tubing (such as: 2-7" / 8 tubing) is used, and a sliding sleeve and a packer string are not run in. During the later development stage, high water production and high water cut seriously affect the oil and gas production. It is necessary to carry out layer selection water plugging operations, and the maximum effective expansion ratio of the water plugging string needs to reach 3.5 times or more.

[0004] The existing technology plugs water through the following three methods. Method 1: Pull out the original completion string, replace the completion string, and run in a special water plugging string to carry out layer selection water plugging. This method has high costs, a long operation cycle, and must shut down the well for production. The kill well operation will pollute the production formation. Method 2: Without pulling out the completion string, carry an expandable packer or a bridge plug through the completion tubing by cable or coiled tubing. After the expandable packer or the bridge plug is expanded to seal the production formation by means of hydraulic pressure, additional drilling pressure, etc., then pump in the plugging agent to carry out layer selection water plugging. However, after the existing expandable packer or bridge plug passes through the completion string, the maximum effective expansion ratio can only reach 2.5 - 3 times. Method 3: Selectively plug water by pumping chemical plugging agents, but the applicable range of this method is limited and the water plugging effect is poor. Summary of the Invention

[0005] The present invention overcomes the deficiencies in the prior art and provides a layer selection water plugging process string of a high-expanded umbrella-shaped support tool and its usage method. By connecting a high-expanded support tool through coiled tubing, passing through a conventional tubing, in a large-diameter casing, the production layers are sealed by means of temporary plugging with a high-viscosity and high-strength temporary plugging agent, and then a permanent plugging agent is pumped in to plug the high-water production layer, ultimately achieving the purpose of controlling water production and increasing production in oil and gas wells.

[0006] The object of the present invention is achieved by the following technical solutions.

[0007] A layer selection water plugging process string of a high-expanded umbrella-shaped support tool, comprising coiled tubing, a coiled tubing joint, a motor head assembly, a permanent plugging agent injection nipple, a high-viscosity and high-strength temporary plugging agent injection nipple, a high-expanded umbrella-shaped support tool, a mechanical coupling locator, and a guide head;

[0008] A coiled tubing is used to carry an umbrella-shaped support and an injection tool assembly to the packer design depth of the downhole water-producing formation, and at the same time pump high-viscosity, high-strength temporary plugging agents, pump plugs, shear balls, spacer fluids and permanent plugging agents pre-set on the ground into the wellbore;

[0009] A coiled tubing joint is used to connect the coiled tubing to the motor head assembly;

[0010] A motor head assembly is used to achieve the purposes of emergency releasing, disconnecting the work string under the condition of pre-setting and inability to release, and one-way isolation of the pressure system of the lower-end tool of the work string;

[0011] A permanent plugging agent injection nipple is used to achieve the purposes of injecting the permanent plugging agent into the water-producing formation and length matching of the work string depth;

[0012] A high-viscosity, high-strength temporary plugging agent injection nipple is used to achieve the purpose of layer-by-layer isolation after injecting the high-viscosity, high-strength temporary plugging agent in a graded and efficient manner and curing it;

[0013] A high-expansion umbrella-shaped support tool is used to support the casing wall of the work string and the high-viscosity, high-strength temporary plugging agent above the high-expansion umbrella-shaped support tool;

[0014] A mechanical collar locator is used to achieve the purpose of depth positioning and depth calibration of the coiled tubing by lifting the coiled tubing;

[0015] A guide head is used to achieve the purposes of guiding and plugging the work string;

[0016] The tail end of the coiled tubing is connected to the head end of the motor head assembly through the coiled tubing joint. The tail end of the motor head assembly is connected to the head end of the permanent plugging agent injection nipple. The tail end of the permanent plugging agent injection nipple is connected to the head end of the high-expansion umbrella-shaped support tool through the high-viscosity, high-strength temporary plugging agent injection nipple. The high-expansion umbrella-shaped support tool is connected to the head end of the mechanical collar locator. The tail end of the mechanical collar locator is connected to the head end of the guide head.

[0017] The high-viscosity and high-strength temporary plugging agent injection sub-section includes an upper connector, an outer cylinder, a rupture disk, a double-sealing sliding sleeve, an oblate injection hole, and a circular injection hole. The outer wall of the tail end of the upper connector is threadedly connected to the inner wall of the head end of the outer cylinder. A limiting step is formed on the inner wall of the lower part of the outer cylinder. N injection holes are opened on the side wall of the outer cylinder above the limiting step, where N≥3. The first-stage injection hole at the lowermost end of the N injection holes is the circular injection hole. The rupture disk is arranged in the outer cylinder to seal the circular injection hole. N-1 oblate injection holes are opened on the side wall of the outer cylinder above the circular injection hole. The double-sealing sliding sleeve is installed in the outer cylinder at the position of the oblate injection hole. The double-sealing sliding sleeve is fixed in the outer cylinder through a sliding sleeve pin to seal the oblate injection hole. The upper-stage double-sealing sliding sleeve is used to limit the position of the lower-stage double-sealing sliding sleeve. An external thread is formed on the outer wall of the tail end of the outer cylinder for connecting other tools.

[0018] The number of the oblate injection holes is more than 3 groups, the number of the double-sealing sliding sleeves is more than 3, and the number of the sliding sleeve pins is more than 3.

[0019] The oblate injection holes are distributed 2-3 per group along the circumferential direction of the outer cylinder. The edge cone angle of the oblate injection hole is 120-150°. The ratio of the transverse maximum diameter to the longitudinal maximum diameter of the oblate injection hole is 1.5-3. The cumulative area of the oblate injection holes within the same circumferential direction of the outer cylinder accounts for more than 25% of the circumferential area of the outer cylinder.

[0020] The number of the circular injection holes is 1 group, and the circular injection holes are distributed 3-4 per group along the circumferential direction of the outer cylinder.

[0021] Shearing balls with the same number as the double-sealing sliding sleeves are sequentially placed in the coiled tubing, and high-viscosity and high-strength temporary plugging agents are arranged between adjacent shearing balls.

[0022] The high-expanded-diameter umbrella-shaped support tool includes an umbrella-shaped suspension cap, an outer support rod, a central tube, an inner support rod, and a support rod locking component. The central tube has a T-shaped hollow tubular structure in the longitudinal section at the tail end. The support rod locking component passes through the central tube and is located at the T-shaped end of the central tube. The umbrella-shaped suspension cap passes through the central tube and is fixed to the head end of the central tube. An outer support rod rotating shaft is arranged inside the umbrella-shaped suspension cap. The head end of the outer support rod is rotatably connected to the outer support rod rotating shaft. A slip block is rotatably installed at the tail end of the outer support rod. The slip block and the support rod locking component are used to achieve the purpose of the outer support rod contracting at the central tube. An inner support rod lower rotating shaft is arranged in the middle of the central tube. The inner support rod is rotatably connected to the inner wall of the outer support rod through the inner support rod lower rotating shaft and the inner support rod upper rotating shaft. The head end of the outer support rod compression spring is fixedly connected to the upper outer wall of the central tube, and the tail end of the outer support rod compression spring is fixedly connected to the inner wall of the outer support rod. The head end of the inner support rod compression spring is fixedly connected to the middle outer wall of the central tube, and the tail end of the inner support rod compression spring is fixedly connected to the inner wall of the outer support rod. The outer support rod compression spring and the inner support rod compression spring are used to achieve the purpose of opening the outer support rod and the inner support rod. A support cloth is arranged on the outer wall of the outer support rod.

[0023] A slip block rotating shaft is arranged at the tail end of the outer support rod. A connecting rod is rotatably installed on the slip block rotating shaft. The connecting rod is fixedly connected to the lower surface of the slip block. A torsion spring is also arranged on one long side of the connecting rod facing the outer support rod.

[0024] A guiding block is formed at the tail end of the outer support rod. The guiding block is located above the slip block. The guiding block has a trapezoidal cross-section structure.

[0025] There are two inner support rod compression springs, namely the inner support rod upper compression spring and the inner support rod lower compression spring respectively.

[0026] A lower connecting part is arranged at the tail end of the support rod locking component. The outer wall of the head end of the lower connecting part is threadedly connected to the inner wall of the tail end of the support rod locking component. The T-shaped end of the central tube extends into the open head end of the lower connecting part and can move up and down along the lower connecting part.

[0027] A pin hole is formed on the outer wall of the central tube. The lower connecting part is fixed to the central tube through a pin.

[0028] An upper connecting part is arranged at the head end of the central tube. The inner wall of the tail end of the upper connecting part is threadedly connected to the outer wall of the head end of the central tube.

[0029] A method for using a high-expanded-diameter umbrella-shaped support tool for layer selection and water plugging technology string is carried out according to the following steps:

[0030] Step 1, running a production string through the well and conducting a pressure test: Use a production string to carry a wellbore cleaning tool with the maximum outer diameter of the simulated process string to conduct wellbore cleaning operations. It is only necessary to confirm that the high-expanded umbrella support tool of the process string can be smoothly and safely lowered to the target water plugging depth. After the production string is run through the well to the target depth, pump into the annulus between the production string and the casing-tubing at the designed pumping rate to test the wellhead pressure, thereby providing comparison pressure data for verifying the pack-off effect after temporary plugging of the pay zone later.

[0031] Step 2, connecting the process string, pre-setting the pump plug and shear ball, and pre-pumping key working fluids: At the surface, connect the tail end of the production string from top to bottom with a production string joint, motor head assembly, permanent plugging agent injection nipple, high-viscosity and high-strength temporary plugging agent injection nipple, high-expanded umbrella support tool, mechanical collar locator, and guide head to obtain the process string. Pre-set the pump plug and shear ball in the process string, and pre-pump an appropriate amount of high-viscosity and high-strength temporary plugging agent, spacer fluid, and permanent plugging agent into the process string.

[0032] Step 3, running in the process string and depth positioning: Open the well, close the casing outlet, lower the process string obtained after connecting in Step 2 to the end of the tubing, lift the process string, position and depth correct it, and then lower the above process string to a depth below the target water-producing pay zone depth of the selected layer for water plugging.

[0033] Step 4, interlayer pack-off and seal verification: Start the pump to pressurize the production string. After opening and setting the high-expanded umbrella support tool, then pressurize and inject the high-viscosity and high-strength temporary plugging agent into the production string in stages. After standing, wait for the high-viscosity and high-strength temporary plugging agent to solidify to achieve interlayer pack-off of the pay zone. Pump into the annulus between the production string and the casing-tubing at the designed pumping rate to test the wellhead pressure and obtain the wellhead pressure at this time. Compare the above wellhead pressure with the wellhead pressure measured in Step 1 to judge the interlayer pack-off effect of the wellbore. If the seal verification fails, wait for the high-viscosity and high-strength temporary plugging agent to hydrate, pull out the process string, and repeat Steps 2 - 4.

[0034] Step 5, pumping in the permanent plugging agent, plugging the water-producing pay zone, waiting for setting, and pressure testing: Start the pump to continue pressurizing the production string, then open the rupture disk circulation valve of the plugging agent injection nipple, pump the pre-set plugging agent from the production string, squeeze the pre-set plugging agent into the target water plugging zone. After waiting for setting, start the pump to continue pressurizing the production string for pressure testing. If the pressure test is unqualified, repeat Steps 2 - 6.

[0035] Step 6, pulling out the process string: Wait for the high-viscosity and high-strength temporary plugging agent to hydrate, and then pull out the process string.

[0036] In step 1, if the work string encounters resistance at a position above the target depth of water plugging, first use a coiled tubing to carry a milling tool to perform downhole reaming and workover operations. Then, lift the coiled tubing to replace the lower milling tool. After replacing it with a hole opener tool that simulates the maximum outer diameter of the work string, perform the hole opening operation again. If the work string still cannot pass after the above operations, abandon the layer selection and water plugging operation.

[0037] In step 4, pump and test pressure from the casing annulus. After the wellhead pressure increases significantly compared to the wellhead test pressure in step 1 and stabilizes at a certain pressure, keep the pressure stable for 10 minutes. And if the pressure drops by less than 1.5 MPa during the pressure stabilization period, it indicates that the seal verification is successful.

[0038] In step 5, after the wellhead pressure increases significantly compared to the wellhead test pressure in step 1 and stabilizes at a certain pressure, keep the pressure stable for 30 minutes. And if the pressure drops by less than 0.7 MPa during the pressure stabilization period, it indicates that the pressure test is qualified.

[0039] In step 6, the steps to retrieve the work string are as follows: Lift the work string. The high reaming umbrella support tool loses the downward pressing force of the coiled tubing. The slip blocks of the outer support rod retract under the action of the torsion spring and are parallel to the outer support rod, placed under the guide block at the end of the outer support rod. The inner support rod is parallel and closely attached to the surface of the central pipe. After the outer support rod and the support cloth are no longer subjected to the downward force and contract slightly, they contact the inner wall of the casing with a small force under the compression spring of the outer support rod. Lift the high reaming umbrella support tool to the end of the tubing. The guide block at the end of the outer support rod guides the umbrella support tool into the tubing. The compression spring of the outer support rod is compressed by the end of the tubing and contracts. The outer diameter of the outer support rod and the support cloth decreases accordingly, and they enter the tubing by sticking to the inner wall of the tubing with a small force. The work string is retrieved under the effective and safe lifting force of the surface coiled tubing equipment.

[0040] The beneficial effects of the present invention are as follows: This string can realize the functions of layer isolation and layer selection for water plugging with an outer diameter expansion of 2.5 times, 3.5 times or more in the casing after passing through the completion string of the oil and gas well; Using this string does not require moving the existing completion string, greatly reducing the cost of water plugging operations and shortening the production shutdown period; Using the advantages of coiled tubing pressure - controlled operation to complete the operation, does not require well killing and will not pollute the formation in the production area; It is not restricted by formation and wellbore conditions and has a wide range of applications; This string can be completely recovered and retrieved without affecting the wellbore integrity and subsequent operations. Description of the Drawings

[0041] Figure 1 is the structural principle schematic diagram of the present invention;

[0042] Figure 2 is the structural schematic diagram of the high - viscosity and high - strength temporary plugging agent injection sub - section in the present invention;

[0043] Figure 3It is a schematic diagram of the principle structure of the high-expanded-diameter umbrella-shaped support tool in the present invention;

[0044] Figure 4 It is a schematic diagram of the principle structure after the high-expanded-diameter umbrella-shaped support tool in the present invention is opened;

[0045] Figure 5 It is a top view after the high-expanded-diameter umbrella-shaped support tool in the present invention is opened;

[0046] Figure 6 It is a bottom view of the umbrella-shaped suspension cap after the high-expanded-diameter umbrella-shaped support tool in the present invention is opened;

[0047] Figure 7 It is a connection schematic diagram of the outer support rod and the slip block of the high-expanded-diameter umbrella-shaped support tool in the present invention;

[0048] In the figure: 1-1 is a coiled tubing; 1-2 is a coiled tubing joint; 1-3 is a motor head assembly; 1-4 is a permanent plugging agent injection nipple; 1-5 is a high-viscosity and high-strength temporary plugging agent injection nipple; 1-6 is a high-expanded-diameter umbrella-shaped support tool; 1-7 is a mechanical coupling locator; 1-8 is a guide head;

[0049] 2-1 is an upper connector; 2-2 is an outer cylinder; 2-3 is the Nth-stage double-sealing sliding sleeve; 2-4 is the Nth-stage double-sealing sliding sleeve pin; 2-5 is the (N-!)-th stage double-sealing sliding sleeve; 2-6 is the (N-1)-th stage double-sealing sliding sleeve pin; 2-7 is the Nth-stage oval injection hole; 2-8 is the second-stage double-sealing sliding sleeve; 2-9 is the second-stage double-sealing sliding sleeve pin; 2-10 is the second-stage oval injection hole; 2-11 is the first-stage circular injection hole with a rupture disk;

[0050] 3-1 is an upper connector; 3-2 is an umbrella-shaped suspension cap; 3-3 is an outer support rod rotating shaft; 3-4 is an outer support rod compression spring; 3-5 is an outer support rod; 3-6 is a central tube; 3-7 is an inner support rod upper rotating shaft; 3-8 is an inner support rod upper compression spring; 3-9 is an inner support rod; 3-10 is an inner support rod lower compression spring; 3-11 is an inner support rod lower rotating shaft; 3-12 is a guide block; 3-13 is a slip block rotating shaft; 3-14 is a slip block; 3-15 is a support rod locking component; 3-16 is a pin; 3-17 is a lower connector, 3-18 is a support cloth; 3-19 is a torsion spring; 3-20 is a connecting rod.

[0051] For those of ordinary skill in the art, without creative efforts, other related drawings can be obtained based on the above drawings. Detailed implementation manners

[0052] The technical solutions of the present invention will be further described below through specific embodiments.

[0053] Embodiment 1

[0054] As Figure 1 shown, a layer selection and water plugging process string of a high-expanded-diameter umbrella-shaped support tool includes a coiled tubing 1-1, a coiled tubing joint 1-2, a motor head assembly 1-3, a permanent plugging agent injection nipple 1-4, a high-viscosity and high-strength temporary plugging agent injection nipple 1-5, a high-expanded-diameter umbrella-shaped support tool 1-6, a mechanical collar locator 1-7, and a guide head 1-8;

[0055] The coiled tubing 1-1 is used to carry the umbrella-shaped support and injection tool assembly to the designed depth for sealing the water-producing layer in the wellbore, and at the same time pump the pre-set high-viscosity and high-strength temporary plugging agent, pump plug, shear ball, spacer fluid, and permanent plugging agent on the ground into the well;

[0056] The coiled tubing joint 1-2 is used to connect the coiled tubing to the motor head assembly;

[0057] The motor head assembly 1-3 is used to achieve the purpose of emergency releasing, disconnecting in the case of pre-setting and unable to release, and one-way isolation from the lower-end tool pressure system of the process string;

[0058] The permanent plugging agent injection nipple 1-4 is used to achieve the purpose of injecting the permanent plugging agent into the water-producing layer and length matching of the process string;

[0059] The high-viscosity and high-strength temporary plugging agent injection nipple 1-5 is used to inject the high-viscosity and high-strength temporary plugging agent in a graded and efficient manner, and after curing, achieve the purpose of interlayer sealing;

[0060] The high-expanded-diameter umbrella-shaped support tool 1-6 is used to support the casing wall of the process string and the high-viscosity and high-strength temporary plugging agent above the high-expanded-diameter umbrella-shaped support tool;

[0061] The mechanical collar locator 1-7 is used to achieve the purpose of depth positioning and depth calibration of the coiled tubing by lifting the coiled tubing;

[0062] The guide head 1-8 is used to achieve the purpose of guiding and plugging the process string;

[0063] The tail end of the coiled tubing 1-1 is connected to the head end of the motor head assembly 1-3 through the coiled tubing joint 1-2. The tail end of the motor head assembly 1-3 is connected to the head end of the permanent plugging agent injection nipple 1-4. The tail end of the permanent plugging agent injection nipple 1-4 is connected to the head end of the high-expanded-diameter umbrella-shaped support tool 1-6 through the high-viscosity and high-strength temporary plugging agent injection nipple 1-5. The high-expanded-diameter umbrella-shaped support tool 1-6 is connected to the head end of the mechanical collar locator 1-7. The tail end of the mechanical collar locator 1-7 is connected to the head end of the guide head 1-8.

[0064] Embodiment 2

[0065] On the basis of Embodiment 1, as Figure 2 shown, the high-viscosity and high-strength temporary plugging agent injection nipple includes an upper connector 2-1, an outer cylinder 2-2, a rupture disc, a double-seal sliding sleeve, an oblate injection hole, and a circular injection hole. The outer wall of the tail end of the upper connector 2-1 is threadedly connected to the inner wall of the head end of the outer cylinder 2-2. A limiting step is formed on the inner wall of the lower part of the outer cylinder 2-2. N injection holes are provided on the side wall of the outer cylinder above the limiting step, where N≥3. The first-stage injection hole at the lowermost end of the N injection holes is a circular injection hole. A rupture disc is arranged in the outer cylinder 2-2 to seal the circular injection hole. N-1 oblate injection holes are provided on the side wall of the outer cylinder above the circular injection hole. A double-seal sliding sleeve is installed in the outer cylinder 2-2 at the position of the oblate injection hole. The double-seal sliding sleeve is fixed in the outer cylinder 2-2 through a sliding sleeve pin to seal the oblate injection hole. The upper-stage double-seal sliding sleeve is used to limit the position of the lower-stage double-seal sliding sleeve. An external thread is formed on the outer wall of the tail end of the outer cylinder 2-2 for connecting other tools.

[0066] The number of oblate injection holes is more than 3 groups, the number of double-seal sliding sleeves is more than 3, and the number of sliding sleeve pins is more than 3.

[0067] 2-3 oblate injection holes are distributed circumferentially on the outer cylinder per group. The edge cone angle of the oblate injection hole is 120-150°. The ratio of the transverse maximum diameter to the longitudinal maximum diameter of the oblate injection hole is 1.5-3. The cumulative area of the oblate injection holes within the same circumference of the outer cylinder accounts for more than 25% of the circumferential area of the outer cylinder.

[0068] The number of circular injection holes is 1 group, and 3-4 circular injection holes are distributed circumferentially on the outer cylinder per group.

[0069] Embodiment 3

[0070] On the basis of Embodiment 2, as Figures 3 to 7As shown in the figure, the high-expansion-diameter umbrella-shaped support tool includes an umbrella-shaped suspension cap 3-2, an outer support rod 3-5, a central tube 3-6, an inner support rod 3-9, and a support rod locking component 3-15. The central tube 3-6 adopts a T-shaped hollow tubular structure with a longitudinal section at the tail end. The support rod locking component 3-15 passes through the central tube 3-6 and is located at the T-shaped end of the central tube 3-6. The umbrella-shaped suspension cap 3-2 passes through the central tube 3-6 and is fixed to the head end of the central tube 3-6. An outer support rod rotating shaft 3-3 is arranged inside the umbrella-shaped suspension cap 3-2. The head end of the outer support rod 3-5 is rotatably connected to the outer support rod rotating shaft 3-3. A slip block 3-14 is rotatably installed at the tail end of the outer support rod 3-5. The slip block 3-14 and the support rod locking component 3-15 are used to achieve the purpose of contracting the outer support rod 3-5 at the central tube 3-6. An inner support rod lower rotating shaft 3-11 is arranged in the middle of the central tube 3-6. The inner support rod 3-9 is rotatably connected to the inner wall of the outer support rod 3-5 through the inner support rod lower rotating shaft 3-11 and the inner support rod upper rotating shaft 3-7. The head end of the outer support rod compression spring 3-4 is fixedly connected to the upper outer wall of the central tube 3-6, and the tail end of the outer support rod compression spring 3-4 is fixedly connected to the inner wall of the outer support rod 3-5. The head end of the inner support rod compression spring is fixedly connected to the middle outer wall of the central tube 3-6, and the tail end of the inner support rod compression spring is fixedly connected to the inner wall of the outer support rod 3-5. The outer support rod compression spring 3-4 and the inner support rod compression spring are used to achieve the purpose of opening the outer support rod 3-5 and the inner support rod 3-9. A support cloth 3-18 is arranged on the outer wall of the outer support rod 3-5.

[0071] A slip block rotating shaft 3-13 is arranged at the tail end of the outer support rod 3-5. A connecting rod 3-20 is rotatably installed on the slip block rotating shaft 3-13. The connecting rod 3-20 is fixedly connected to the lower surface of the slip block 3-14. A torsion spring 3-19 is also arranged on the long end side of the connecting rod 3-20 facing the outer support rod 3-5.

[0072] A guide block 3-12 is formed at the tail end of the outer support rod 3-5. The guide block 3-12 is located above the slip block 3-14. The guide block 3-12 adopts a trapezoidal cross-sectional structure.

[0073] There are two inner support rod compression springs, namely the inner support rod upper compression spring 3-8 and the inner support rod lower compression spring 3-10.

[0074] A lower connecting piece 3-17 is arranged at the tail end of the support rod locking component 3-15. The outer wall of the head end of the lower connecting piece 3-17 is threadedly connected to the inner wall of the tail end of the support rod locking component 3-15. The T-shaped end of the central tube 3-6 extends into the open head end of the lower connecting piece 3-17 and can move up and down along the lower connecting piece 3-17.

[0075] Pin holes are provided on the outer wall of the central pipe 3-6, and the lower connecting piece 3-17 is fixed to the central pipe 3-6 through a pin 3-16.

[0076] An upper connecting piece 3-1 is provided at the head end of the central pipe 3-6, and the inner wall of the tail end of the upper connecting piece 3-1 is threadedly connected to the outer wall of the head end of the central pipe 3-6.

[0077] Example 4

[0078] A method for using a high-expanded-diameter umbrella-shaped supporting tool for layer-selective water plugging process string is carried out according to the following steps:

[0079] Step 1: Circulate the coiled tubing and conduct a pressure test. The coiled tubing is used to carry out wellbore cleaning with a wellbore cleaning tool simulating the maximum outer diameter of the process string, and it is confirmed whether the high-expanded-diameter umbrella-shaped supporting tool for layer-selective water plugging process string can be smoothly and safely lowered to the water plugging target depth. If there is a blockage at a position above the water plugging target depth, first, the coiled tubing should be used to carry out reaming and well repair operations with a milling tool, and then the wellbore cleaning operation should be carried out again. If it still cannot pass, the layer-selective water plugging operation should be abandoned. After the coiled tubing is circulated to the target depth, according to the designed pumping displacement, pump from the annulus between the coiled tubing and the casing-tubing, and test the wellhead pressure to provide comparison data for verifying the sealing effect after temporary plugging between production layers.

[0080] Step 2: Connect the string, pre-place the pump plug and shear balls, and pre-pump the key working fluid. First, connect the coiled tubing joint 1-2 to the coiled tubing 1-1 (reverse injection end), then connect the coiled tubing joint 1-2 to the manifold at the outlet end of the pumping equipment equipped with a plug valve, and connect the other end (forward injection end) of the coiled tubing joint 1-1 to the pumping equipment. Open the plug valves at both ends, first pump in an appropriate amount of clear water to fill the coiled tubing, and then pump in an appropriate amount of spacer fluid, permanent plugging agent, and spacer fluid in reverse order. Close the reverse injection end plug valve, disconnect the connection between the plug valve and the outlet end of the pumping equipment, place the high-viscosity and high-strength temporary plugging agent pump plug into the manifold connecting the outlet end of the pumping equipment and the plug valve, and then connect again. Open the reverse injection end plug valve, start the pump, and pump in an appropriate amount of high-viscosity and high-strength temporary plugging agent in reverse, and then close the reverse injection end plug valve. Then, in accordance with the aforementioned method of placing the high-viscosity and high-strength temporary plugging agent pump plug, place the high-viscosity and high-strength temporary plugging agent injection nipple slip shear balls 1, 2, and 3 in sequence. An appropriate amount of high-viscosity and high-strength temporary plugging agent is pumped between the shear balls. The outer diameters of the pump plug and shear balls should meet the requirements for effectively and smoothly moving up and down in the coiled tubing 1-1. After the pumping of the high-viscosity and high-strength temporary plugging agent is completed, stop the pump, disconnect the coiled tubing joint 1-2 from the outlet end of the pumping equipment, quickly connect the connected motor head assembly 1-3, permanent plugging agent injection nipple 1-4, high-viscosity and high-strength temporary plugging agent injection nipple 1-5, high-expanded-diameter umbrella-shaped supporting tool 1-6, mechanical collar locator 1-7, and guide head 1-8 to support the injection string to the coiled tubing joint 1-2, and close the forward injection end plug valve.

[0081] Step 3: Lower the string and position and depth-check it. Open the well, lower the high-expanded-diameter umbrella-shaped support tool for layer-selective water plugging process string to a certain depth below the end of the tubing. Lift the process string, and when the positioning block of the mechanical coupling locator 7 touches the end of the tubing, increase the hook load. When the hook load gauge at the wellhead of the coiled tubing equipment shows beyond normal fluctuations, determine the position of the end of the tubing and correct the depth of the coiled tubing to be consistent with the depth of the end of the tubing. Then lower the process string to a depth below the designed depth at the depth position of the target water-producing layer for layer-selective water plugging.

[0082] Step 4: Interlayer isolation and seal checking. Open the positive injection end plug valve of the coiled tubing 1-1, start the pump and pressurize to Pressure 1. Under the action of the pressure difference inside and outside the process string, the shear pins of the high-expanded-diameter umbrella-shaped support tool 1-6 are sheared, the support umbrella locking assembly moves downward, and the support umbrella opens the evenly distributed N groups of support rods and support cloth under the action of multiple groups of springs. A thin, foldable, and high-strength material support cloth is connected between the support rods, and the front support slip blocks at the edge of the support umbrella are in arc contact with the casing wall. Press down the coiled tubing and gradually increase the weight on bit to a certain tonnage to ensure that the process string is stable and seated on the inner wall of the casing. Pressurize the inside of the coiled tubing 1-1 to Pressure 2, open the bypass valve beside the rupture disk at the lowermost end of the high-viscosity and high-strength temporary plugging agent injection sub-section 1-5, and conduct the first-stage high-viscosity and high-strength temporary plugging agent injection. After the pressure inside the coiled tubing 1-1 increases and stabilizes to a certain value, it indicates the end of the first-stage high-viscosity and high-strength temporary plugging agent injection. Then gradually pressurize to Pressure 3, and use the shear ball 1 of the high-viscosity and high-strength temporary plugging agent injection sub-section to shear the pin of the sealing sleeve 1. The pin breaks, the sealing sleeve 1 moves downward, the second-stage high-viscosity and high-strength temporary plugging agent injection port opens, and the first-stage injection port is sealed and closed by the sealing sleeve 1, and the second-stage high-viscosity and high-strength temporary plugging agent injection is carried out. Then, in accordance with the opening injection method of the second-stage high-viscosity and high-strength temporary plugging agent, pressurize the inside of the coiled tubing 1-1 to Pressure 4, use the shear ball 2 to open the third-stage injection port and seal the second-stage injection port, and complete the third-stage high-viscosity and high-strength temporary plugging agent injection. Finally, pressurize the inside of the coiled tubing 1-1 to Pressure 5, use the shear ball 3 to shear the sealing sleeve 3 of the high-viscosity and high-strength temporary plugging agent injection sub-section 1-5, seal the third-stage injection port, realize the full closure of the string, and the high-viscosity and high-strength temporary plugging agent pump plug enters the position before the shearing of the sealing sleeve 3. After the injection of the high-viscosity and high-strength temporary plugging agent into the annulus in three stages is completed, let it stand for a certain period of time until the high-viscosity and high-strength temporary plugging agent solidifies to realize the interlayer isolation. According to the injection displacement of the wellhead pressure test in Step 1, pump and inject the test wellhead pressure from the annulus between the coiled tubing and the tubing-casing. If the wellhead pressure increases significantly and reaches the required pressure for pumping the plugging agent as designed, it indicates that the interlayer temporary plugging and isolation is successful. After the pressure test is completed, open the surface flow path to relieve the pressure to the open-well pressure, and then close the pressure relief process and the annulus between the tubing and the casing. If the seal checking fails, after the high-viscosity and high-strength temporary plugging agent hydrates, pull out the string and repeat Steps 2 to 4.

[0083] Step 5: Pump in the permanent plugging agent to plug the water-producing layer, wait for setting, and conduct pressure testing. Apply pressure from within the coiled tubing 1-1 to a pressure of 6, open the bypass valve of the rupture disc of the permanent plugging agent injection nipple 1-4, and pump in the pre-set permanent plugging agent from within the coiled tubing 1-1 to squeeze the permanent plugging agent into the target water plugging layer. After waiting for setting for a certain period of time, conduct pressure testing. If the pressure testing fails, repeat Steps 2 to 6.

[0084] Step 6: Pull out the tubing string. After the high-viscosity and high-strength temporary plugging agent hydrates, lift the workover tubing string. The high-expansion umbrella support tool 1-6 loses the downward pressing force of the coiled tubing 1-1. The upper slip blocks on the umbrella support rod retract under the action of the spring and are located under the chamfered wedge block assembly provided at the front end of the support rod, parallel to and closely attached to the surface of the support rod. The umbrella support rod and the high-strength support cloth are no longer subject to a large downward force. After a small range of contraction, they contact the inner wall of the casing with a small force under the action of the support rod spring. Lift the high-expansion umbrella support tool to the end of the tubing. The chamfered wedge block at the front end of the support rod guides the umbrella support tool into the tubing. The support rod spring contracts under the extrusion of the end of the tubing, and the outer diameter of the support rod and the support cloth decreases accordingly, and they are attached to the inner wall of the tubing with a small force. The workover tubing string is pulled out under the effective and safe lifting force of the surface coiled tubing equipment.

[0085] For the process method of simultaneous production from two or more layers and plugging the intermediate layer, it needs to be run in three trips. In the first trip, run in to plug the lower part of the intermediate layer. After the temporary plugging is completed, drop a ball to shear and release the high-expansion umbrella support and injection tool from the motor head assembly, and pull out the upper coiled tubing joint and the coiled tubing. The other implementation steps and methods are the same as those of the process method for simultaneous production from two or more layers and plugging the topmost layer. In the second trip, run in to plug the upper part of the intermediate layer. The implementation steps and methods are the same as those of the process method for simultaneous production from two or more layers and plugging the topmost layer. In the third trip, after the high-viscosity and high-strength temporary plugging agent hydrates, use the fishing neck reserved after releasing the motor head assembly 3 to fish and pull out the high-expansion umbrella support and injection tool tubing string. The workover tubing strings in the first and second trips are the same as the workover tubing string for simultaneous production from two or more layers and plugging the topmost layer.

[0086] This workover tubing string and method have the characteristics of not moving the tubing string, not affecting normal production, short construction period, high efficiency, low cost, safety and reliability, strong operability, and wide application range.

[0087] For ease of explanation, spatial relative terms such as "upper", "lower", "left", "right", etc. are used in the embodiments to describe the relationship of one element or feature shown in the figures relative to another element or feature. It should be understood that, in addition to the orientation shown in the figures, the spatial terms are intended to include different orientations of the device during use or operation. For example, if the device in the figures is inverted, an element described as being "below" other elements or features will be positioned "above" the other elements or features. Thus, the exemplary term "below" can encompass both upper and lower orientations. The device may be otherwise positioned (rotated 90 degrees or at other orientations), and the spatial relative descriptions used herein may be interpreted accordingly.

[0088] Moreover, relational terms such as "first" and "second" are used solely to distinguish one component with the same name from another, and do not necessarily require or imply any actual relationship or order between these components.

[0089] The present invention has been described in detail above, but the above content is only the preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. A high-expansion-diameter umbrella-shaped supporting tool for selected-layer water plugging process string, characterized in that: It includes coiled tubing, coiled tubing connector, motor head assembly, permanent plugging agent injection nipple, high-viscosity and high-strength temporary plugging agent injection nipple, high-expansion umbrella support tool, mechanical collar locator and guide head; The coiled tubing is used to carry the umbrella support and injection tool assembly to the designed depth for isolating the water-producing formation downhole, and at the same time pump the pre-set high-viscosity and high-strength temporary plugging agent, pump plug, shear ball, spacer fluid and permanent plugging agent on the ground into the well; The coiled tubing connector is used to connect the coiled tubing with the motor head assembly; The motor head assembly is used to achieve the purposes of emergency releasing, disconnecting in case of non-releasable pre-setting of the process string and one-way isolation of the pressure system of the lower-end tool of the process string; The permanent plugging agent injection nipple is used to achieve the purposes of injecting the permanent plugging agent for the water-producing formation and length matching of the process string depth; The high-viscosity and high-strength temporary plugging agent injection nipple is used to inject the high-viscosity and high-strength temporary plugging agent in a graded and efficient manner, and after curing, achieve the purpose of interlayer isolation; The high-expansion umbrella support tool is used to support the casing wall of the process string and the high-viscosity and high-strength temporary plugging agent above the high-expansion umbrella support tool; The mechanical collar locator is used to achieve the purpose of depth positioning and depth calibration of the coiled tubing by lifting the coiled tubing; The guide head is used to achieve the purposes of guiding and plugging the process string; The tail end of the coiled tubing is connected to the head end of the motor head assembly through the coiled tubing connector. The tail end of the motor head assembly is connected to the head end of the permanent plugging agent injection nipple. The tail end of the permanent plugging agent injection nipple is connected to the head end of the high-expansion umbrella support tool through the high-viscosity and high-strength temporary plugging agent injection nipple. The high-expansion umbrella support tool is connected to the head end of the mechanical collar locator. The tail end of the mechanical collar locator is connected to the head end of the guide head.

2. The selective layer water plugging technology string of a high-expanded-diameter umbrella-shaped support tool according to claim 1, wherein: The high-viscosity and high-strength temporary plugging agent injection nipple includes an upper connector, an outer cylinder, a rupture disk, a double-seal sliding sleeve, an oval injection hole and a circular injection hole. The outer wall of the tail end of the upper connector is threadedly connected to the inner wall of the head end of the outer cylinder. A limiting step is formed on the inner wall of the lower part of the outer cylinder. N injection holes are opened on the side wall of the outer cylinder above the limiting step, where N≥3. The first-stage injection hole at the lowermost end of the N injection holes is the circular injection hole. The rupture disk is arranged in the outer cylinder to seal the circular injection hole. N - 1 oval injection holes are opened on the side wall of the outer cylinder above the circular injection hole. The double-seal sliding sleeve is installed in the outer cylinder at the oval injection hole. The double-seal sliding sleeve is fixed in the outer cylinder through a sliding sleeve pin to seal the oval injection hole. The upper-stage double-seal sliding sleeve is used to limit the position of the lower-stage double-seal sliding sleeve. External threads are formed on the outer wall of the tail end of the outer cylinder for connecting other tools.

3. A layer-selective water plugging process string of a high-expanded-diameter umbrella-shaped support tool according to claim 2, characterized in that: The number of the oval injection holes is more than 3 groups, the number of the double-sealing sliding sleeves is more than 3, and the number of the sliding sleeve pins is more than 3; 2-3 oval injection holes are circumferentially distributed along the outer cylinder per group, the edge cone angle of the oval injection hole is 120-150°, the ratio of the transverse maximum diameter to the longitudinal maximum diameter of the oval injection hole is 1.5-3, and the cumulative area of the oval injection holes along the same circumference of the outer cylinder accounts for more than 25% of the circumferential area of the outer cylinder; the number of the circular injection holes is 1 group, and 3-4 circular injection holes are circumferentially distributed along the outer cylinder per group; Shearing balls with the same number as the double-sealing sliding sleeves are sequentially placed in the coiled tubing, and a high-viscosity and high-strength temporary plugging agent is arranged between adjacent shearing balls.

4. The selective layer water plugging process string of a high-expanded-diameter umbrella-shaped support tool according to claim 1, wherein: The high-diameter-expanding umbrella-shaped supporting tool includes an umbrella-shaped suspension cap, an outer support rod, a central tube, an inner support rod and a support rod locking component. The central tube adopts a T-shaped hollow tubular structure with a longitudinal section at the tail end. The support rod locking component passes through the central tube and is located at the T-shaped end of the central tube. The umbrella-shaped suspension cap passes through the central tube and is fixed to the head end of the central tube. An outer support rod rotating shaft is arranged in the umbrella-shaped suspension cap. The head end of the outer support rod is rotatably connected to the outer support rod rotating shaft. A slip block is rotatably installed at the tail end of the outer support rod. The slip block and the support rod locking component are used to achieve the purpose of the outer support rod shrinking at the central tube. An inner support rod lower rotating shaft is arranged in the middle of the central tube. The inner support rod is rotatably connected to the inner wall of the outer support rod through the inner support rod lower rotating shaft and the inner support rod upper rotating shaft. The head end of the outer support rod compression spring is fixedly connected to the upper outer wall of the central tube, and the tail end of the outer support rod compression spring is fixedly connected to the inner wall of the outer support rod. The head end of the inner support rod compression spring is fixedly connected to the middle outer wall of the central tube, and the tail end of the inner support rod compression spring is fixedly connected to the inner wall of the outer support rod. The outer support rod compression spring and the inner support rod compression spring are used to achieve the purpose of opening the outer support rod and the inner support rod. A support cloth is arranged on the outer wall of the outer support rod.

5. A layer selection and water plugging process string of a high expansion diameter umbrella-shaped support tool according to claim 4, characterized in that: A slip block rotating shaft is arranged at the tail end of the outer support rod. A connecting rod is rotatably installed on the slip block rotating shaft. The connecting rod is fixedly connected to the lower surface of the slip block. A torsion spring is further arranged on the long end side of the connecting rod facing the outer support rod. A guide block is formed at the tail end of the outer support rod. The guide block is located above the slip block. The guide block adopts a trapezoidal cross-section structure. The inner support rod compression spring is two, namely an inner support rod upper compression spring and an inner support rod lower compression spring.

6. The high-expanded umbrella-shaped support tool selected layer water shutoff technology string according to claim 4, characterized in that: A lower connecting piece is arranged at the tail end of the support rod locking component. The outer wall of the head end of the lower connecting piece is threadedly connected to the inner wall of the tail end of the support rod locking component. The T-shaped end of the central tube extends into the open head end of the lower connecting piece and can move up and down along the lower connecting piece. A pin hole is formed in the outer wall of the central tube, and the lower connecting piece is fixed to the central tube through a pin. An upper connecting piece is arranged at the head end of the central tube, and the inner wall of the tail end of the upper connecting piece is threadedly connected to the outer wall of the head end of the central tube.

7. A method for using a high-expanded-diameter umbrella-shaped support tool for layer selection and water plugging process string, characterized in that: The following steps are carried out: Step 1, Circulate the coiled tubing and conduct a pressure test: Use the coiled tubing to carry a well-circulating tool simulating the maximum outer diameter of the process string to conduct a well-circulating operation. It is only necessary to confirm that the high-expanded umbrella-shaped support tool of the process string can be smoothly and safely lowered to the target water plugging depth. After the coiled tubing circulates to the target depth, pump into the annulus between the coiled tubing and the casing-tubing at the designed pumping displacement to test the wellhead pressure, so as to provide comparison pressure data for verifying the packer effect after temporary plugging of the pay zone. Step 2, Connect the process string, preset the pump plug and shear ball, and pre-pump the key working fluid: At the surface, connect the tail end of the coiled tubing from top to bottom with a coiled tubing joint, a motor head assembly, a permanent plugging agent injection nipple, a high-viscosity and high-strength temporary plugging agent injection nipple, a high-expanded umbrella-shaped support tool, a mechanical collar locator, and a guide head to obtain the process string. Preset the pump plug and shear ball in the process string, and pre-pump an appropriate amount of high-viscosity and high-strength temporary plugging agent, spacer fluid, and permanent plugging agent into the process string. Step 3, Lower the process string and position and depth check: Open the well and close the casing outlet. Lower the process string obtained after connecting in Step 2 to the end of the tubing. Lift the process string, position and depth check, and then lower the above process string to a depth below the target water-producing layer depth of the selected layer for water plugging by the designed depth. Step 4, Interlayer sealing and seal verification: Start the pump to pressurize the coiled tubing. After opening and setting the high-expanded umbrella-shaped support tool, then pressurize the coiled tubing in stages to inject a high-viscosity and high-strength temporary plugging agent. After standing, wait for the high-viscosity and high-strength temporary plugging agent to solidify to achieve the sealing between the pay zones. Pump into the annulus between the coiled tubing and the casing-tubing at the designed pumping displacement to test the wellhead pressure and obtain the wellhead pressure at this time. Compare the above wellhead pressure with the wellhead pressure measured in Step 1 to judge the interlayer sealing effect of the wellbore. If the seal verification fails, wait for the high-viscosity and high-strength temporary plugging agent to hydrate, then pull out the process string, and repeat Steps 2 - 4. Step 5, Pump in the permanent plugging agent, plug the water-producing layer, wait for setting, and pressure test: Start the pump to continue pressurize the coiled tubing, and then open the rupture disk circulation valve of the plugging agent injection nipple to pump the preset plugging agent from the coiled tubing and squeeze the preset plugging agent into the target water plugging layer. After waiting for setting, start the pump to continue pressurize the coiled tubing for pressure testing. If the pressure test is unqualified, repeat Steps 2 - 6. Step 6, Pull out the process string: Wait for the high-viscosity and high-strength temporary plugging agent to hydrate, and then pull out the process string.

8. The usage method of a high-expanded-diameter umbrella-shaped support tool for a selective layer water plugging technology string according to claim 7, characterized in that: In step 1, if the work string encounters resistance at a position above the target depth of water plugging, first use coiled tubing to carry a milling tool to perform downhole reaming workover. Then, lift the coiled tubing to replace the milling tool with a lower one. After replacing it with a hole opener that simulates the maximum outer diameter of the work string, perform the hole opening operation again. If the work string still cannot pass after the above operations, abandon the selected layer water plugging operation.

9. The using method of a high-expanded-diameter umbrella-shaped support tool for layer selection and water plugging process string according to claim 7, characterized in that: In step 4, pump pressure test through the casing annulus. After the wellhead pressure increases significantly compared to the wellhead pressure tested in step 1 and stabilizes at a certain pressure, maintain the pressure for 10 minutes. If the pressure drops by less than 1.5 MPa during the pressure stabilization period, it indicates that the seal verification is successful. In step 5, after the wellhead pressure increases significantly compared to the wellhead pressure tested in step 1 and stabilizes at a certain pressure, maintain the pressure for 30 minutes. If the pressure drops by less than 0.7 MPa during the pressure stabilization period, it indicates that the pressure test is qualified.

10. The usage method of a high-expanded-diameter umbrella-shaped support tool selected layer water plugging technology string according to claim 7, characterized in that: In step 6, the steps to retrieve the work string: Lift the work string. The high reaming umbrella support tool loses the downward pressing force of the coiled tubing. The slip blocks of the outer support rod retract under the action of the torsion spring and are parallel to the outer support rod, placed under the guide block at the end of the outer support rod. The inner support rod is parallel and closely attached to the surface of the central pipe. After the outer support rod and the support cloth are no longer subjected to downward forces and contract slightly, they contact the inner wall of the casing with a small force under the compression spring of the outer support rod. Lift the high reaming umbrella support tool to the end of the tubing. The guide block at the end of the outer support rod guides the umbrella support tool into the tubing. The compression spring of the outer support rod contracts under the extrusion of the end of the tubing, and the outer diameter of the outer support rod and the support cloth decreases accordingly, and it enters the tubing by sticking to the inner wall of the tubing with a small force. The work string is retrieved under the effective and safe lifting force of the surface coiled tubing equipment.

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