Offshore oilfield multilayer real-time separate layer measurement and control safety production pipe string and use method

Abstract

The present application relates to a production string for oil development and a use method, in particular to a multi-layer real-time separate layer measurement and control safety production string for offshore oilfield. The production string comprises an electric pump overhang cylinder, an electric pump unit, an electric pump cable, a signal cable, a safety valve, a cable through packer, a hydraulic transmission joint, a check valve, a hydraulic drainage device, a plurality of compression type packers, a plurality of measurement and control devices, a tubing, a plug, and a pressure transmission pipeline. The production string has the advantages of realizing the multi-layer real-time separate layer measurement and control function of the electric pump lifting well in the offshore oilfield, improving the utilization efficiency of the oil well, overcoming the problem that the large-scale electric pump lifting well in the offshore application cannot realize the hanging of the separate layer string and the setting of the compression type packer to realize the separate layer, and has a wide application range.

Description

TECHNICAL FIELD

[0001] The present application relates to a production string for oil development, in particular to a real-time multi-layer separate layer measurement and control safety production string for offshore oilfield and a use method thereof. BACKGROUND

[0002] At present, the development of offshore oilfield is affected by high drilling and workover operation cost, limited number of wellbores arranged in the same oil production platform, and the need to equip a considerable number of oil production platforms to complete the injection-production well configuration, and the like, and the imperfect injection-production well pattern has become one of the important factors restricting the improvement of recovery efficiency, which seriously affects the development efficiency of offshore oilfield. Although the injection wells in offshore have realized the separate layer supplemental formation energy injection according to the required water injection amount of each layer, due to the fact that the offshore oil wells still mostly adopt the development mode of electric pump lifting and full-well combination production, the injection time and water breakthrough time of each layer section of the multi-layer well with large interlayer difference are different, the interlayer contradiction of low injection-production correspondence rate and low reserve producing rate of non-main layer still exists, which directly affects the oil production rate and the improvement of oilfield development benefit, which is a technical problem to be solved for the electric pump lifting oil production of offshore multi-layer well. Reasonable real-time multi-layer separate layer measurement and control technology and its integrated application can effectively alleviate the influence of interlayer contradiction on oil production, improve the interlayer producing condition, and achieve the purpose of high-efficiency tapping of remaining oil reservoir.

[0003] Chinese utility model patent CN 204492776 U discloses an online adjustment separate layer production string, which can realize oil well layer switching without moving the string, effectively control the communication or closing state of the production layer, and solve the separate layer production problem of multi-layer long well section oil well, but the string adopts the separate layer mode of sealing plug cooperation, and this kind of string still needs to first lower the sealing cylinder with a matched sealing plug before lowering the separate layer adjustment string, which has many field construction procedures and complex process, can only realize the separate layer regulation and control of two to three layers, and when the separate layer number needs to be changed due to the change of geological development plan in the later period, the working cylinder needs to be fished out and reset, which is time-consuming and laborious.

[0004] Chinese utility model patent CN 203685147 U discloses an offshore separate layer sand prevention separate layer oil production and separate layer test integrated string, which realizes selective production of oil layer and effectively alleviates the influence of interlayer contradiction on oil well productivity. The integrated string uses the mode of three pressure transmission pipelines and one signal optical fiber to transmit signals, needs more cables lowered into the well, has high cost and large construction risk, and the downhole switch controlled by the pressure transmission pipeline can only realize the change between open and closed states, cannot realize real-time regulation and control according to the change of production dynamics, and has low automation degree.

[0005] The Chinese invention patent CN107420084B discloses a real-time regulation and control downhole gas-liquid separation combined lifting system which can be hung, comprising a tubing, the tubing is connected with a hanging tee joint assembly, a jet pump lifting system is arranged in the hanging tee joint assembly, an electric pump lifting system assembly is hung at a first port of a lower end of the hanging tee joint assembly, and a gas-liquid separation system assembly is connected to the second port of the lower end of the hanging tee joint assembly through the gas gathering tubing; further comprising a flow control valve and a visual control device on the ground; the visual control device is connected with the electric pump lifting system assembly, the gas-liquid separation system assembly and the flow control valve. The invention establishes an electric pump + jet pump combined lifting system without external high-pressure power liquid, and uses the high-pressure rich liquid flow through the electric pump as power liquid to pump the separated rich gas flow and lift it to the wellhead. However, the invention only realizes downhole gas-liquid separation, widens the application range of conventional electric pumps in high-gas-content oil well conditions, and does not solve the problem of interlayer differences in offshore oilfield sanding oil wells.

[0006] Therefore, in view of the above problems, a kind of offshore oilfield multilayer real-time layering safety production pipe column with reasonable design and effective improvement is provided to solve the above problems, slow down the influence of interlayer contradiction of offshore oilfield on oil production and improve development effect. SUMMARY

[0007] The main purpose of the present application is a kind of offshore oilfield multilayer real-time layering safety production pipe column and use method, the pipe column can realize the multilayer section layering of offshore oilfield electric pump lifting well, and carry out real-time measurement and control, slow down the influence of interlayer contradiction of offshore oilfield on oil production, overcome the shortcomings and deficiencies in the prior art.

[0008] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0009] The application provides a multi-layer real-time separated layer measurement and control safety production pipe string for offshore oil fields, which comprises an electric pump load-bearing cylinder, an electric pump unit, an electric pump cable, a signal cable, a safety valve, a cable-passing packer, a hydraulic transmission joint, a check valve, a hydraulic flow guiding device, a plurality of compression type packers, a plurality of measurement and control devices, a tubing, a plug and a pressure transmission pipeline; the safety valve, the cable-passing packer, the hydraulic transmission joint, the check valve, the electric pump load-bearing cylinder, the hydraulic transmission joint, the hydraulic flow guiding device, the compression type packer, the measurement and control device and the plug are sequentially connected from top to bottom; the electric pump unit is arranged in the electric pump load-bearing cylinder, the electric pump cable is connected to the outside of the electric pump unit, and the plurality of measurement and control devices are connected in series through the signal cable; the two hydraulic transmission joints are connected through the pressure transmission pipeline, and the pressure transmission pipeline is arranged on the outside of the electric pump load-bearing cylinder. The hydraulic transmission of the compression type packer at the lower end of the electric pump unit is completed through the pressure transmission pipeline, and the overall compression type packer of the pipe string is separated and sealed by one-time pressurization.

[0010] Further, the electric pump load-bearing cylinder has a double-layer structure of an inner tube and an outer tube, the electric pump unit is arranged on the inner tube, and the outer tube of the electric pump load-bearing cylinder is provided with symmetrical liquid inlet grooves to provide a liquid flow channel for the electric pump unit.

[0011] Further, the electric pump load-bearing cylinder is provided with a cable passing hole at the upper end, and the electric pump cable led out of the electric pump unit can be led out of the cable passing hole.

[0012] Further, the outer side of the hydraulic transmission joint is further provided with a cable protection groove and a communication hole, and the pressure transmission pipeline is sealingly connected through the sealing nails and the communication hole of the hydraulic transmission joint.

[0013] Further, the hydraulic flow guiding device comprises a valve seat, a valve ball, an intermediate sleeve, a sealing rubber ring, a sealing plunger, a constant pressure shear pin, a lower joint and a load-bearing rod; the valve seat, the intermediate sleeve and the lower joint are sequentially connected through threads to form an external combination; the valve ball, the sealing rubber ring, the sealing plunger and the load-bearing rod are sequentially arranged in the external combination; the constant pressure shear pin is fixed in the lower joint through a threaded hole, and the constant pressure shear pin simultaneously fixes the valve ball, the sealing rubber ring, the sealing plunger and the load-bearing rod arranged in the external combination. The constant pressure shear pin is sheared when the internal pressure reaches 20 MPa, the sealing rubber ring, the sealing plunger and the load-bearing rod move downward, the valve seat and the valve ball restore cooperation to prevent liquid above the valve seat and the valve ball from flowing downward, and the sealing plunger loses sealing cooperation with the intermediate sleeve.

[0014] Further, the intermediate sleeve is provided with symmetrically distributed balance holes. The balance holes can realize internal and external communication.

[0015] Further, the measuring and controlling device comprises an upper joint, a bridging cable, an outer sleeve, a circuit board, a protection tube, a motor, a speed reducer, a sealed shaft, a switch sleeve and a lower joint; the upper joint is fixed on the upper end of the outer sleeve, the protection tube is placed in the sleeve, the circuit board, the motor, the speed reducer and the sealed shaft are sequentially placed in the protection tube, and the switch sleeve is arranged at the lower end of the sealed shaft; the lower joint is fixed on the lower end of the outer sleeve; the bridging cable is bridged to the upper joint through a sealed dowel. The bridging cable transmits signal instructions to the circuit board, the circuit board controls the motor to reverse, the rotary motion output by the motor is converted into the axial linear motion of the sealed shaft, and the axial linear motion of the sealed shaft drives the opening and closing of the switch sleeve.

[0016] To achieve the above object, the present application adopts the following technical solutions:

[0017] A use method of a multi-layer real-time separate layer measuring and controlling safety production pipe string for offshore oilfield, comprising the following steps:

[0018] The built-in switch sleeve of the measuring and controlling device of each layer section is controlled to be in an open state through a signal cable, the pressure inside and outside the oil pipe is kept in the same pressure system, and the compression type packer is prevented from being accidentally and prematurely set due to pressure influence;

[0019] After the pipe string is completely lowered to the designed position in the well, the built-in switch sleeve of the measuring and controlling device of each layer section is controlled to be in a closed state, the pressure of the oil pipe at the wellhead is pressed, the liquid pressure acts on the cable packer, and the compression type packer is simultaneously acted on through the hydraulic transmission connector and the pressure transmission pipeline, so that all the packers of the pipe string are set; the pressure continues to rise, the built-in pressure setting shear pin of the hydraulic flow guiding device is sheared, the sealing plunger and the load rod move downward, the valve seat and the valve ball restore cooperation so that the liquid above cannot continue to flow downward, and the sealing rubber ring, the sealing plunger and the middle sleeve lose the sealing cooperation of the balance hole and the communication inside and outside the balance hole;

[0020] During normal production, the built-in switch sleeve of the measuring and controlling device of each layer section is controlled to be in an open state through a signal cable, the produced liquid of the formation enters the oil pipe through the measuring and controlling device, flows upward to the hydraulic flow guiding device and then flows out to the outside of the pipe string from the balance hole, and then enters the electric pump suspension cylinder of the electric pump unit, is lifted to the ground and is lifted to the ground.

[0021] Compared with the prior art, the present application has the following advantages:

[0022] 1) The pipe string of the present application has the functions of multi-layer separate layer real-time measuring and controlling of the electric pump lifting well of offshore oilfield, and improves the utilization efficiency of the oil well;

[0023] 2) The pipe string of the present application can overcome the problem that the compression type packer cannot be set for the suspended separate layer pipe string of the electric pump lifting well with a large scale of offshore application, and has a wide application range;

[0024] 3) The tubing of this invention can connect multiple measurement and control devices in series with a single signal cable, enabling control of multiple layers, high efficiency, convenient construction, reliability, safety, and high success rate.

[0025] In summary, the tubing string described in this invention fills the current gap in offshore oilfields where there is no multi-layer real-time stratified monitoring and control tubing string for real-time monitoring and control of multiple sections in electric pump lift wells. It offers significant technical and economic benefits. Using this invention for real-time stratified monitoring and control of multiple oil layers in offshore oilfields can mitigate the impact of inter-layer conflicts on oil production, maximize the productivity of medium and low permeability layers, increase oil production speed, and improve development results. Real-time monitoring and control of oil production is achieved by transmitting electrical energy and data signals through a single signal cable. Operation is simple and convenient, allowing for real-time remote monitoring and control, reducing the number of operations and saving operating costs. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the hydraulic transmission joint of the present invention;

[0028] Figure 3 This is a schematic diagram of the hydraulic drainage device according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the measurement and control device according to an embodiment of the present invention.

[0030] In the diagram: 1. Safety valve, 2. Cable packer, 3. Signal cable, 4. Electric pump cable, 5. Hydraulic transmission connector, 6. Check valve, 7. Electric pump suspension cylinder, 8. Pressure transmission pipeline, 9. Electric pump unit, 10. Hydraulic drainage device, 11. Compression packer, 12. Monitoring and control device, 13. Oil pipe, 14. Plug, 501. Cable protection groove, 502. Connecting hole, 503. Sealing pin, 504. Hydraulic transmission body, 1001. Valve seat, 1002. Valve ball, 1003. Intermediate sleeve, 1004. Sealing ring, 1005. Balance hole, 1006. Sealing plunger, 1007. Constant pressure shear pin, 1008. Lower connector, 1009. Load-bearing rod; 1201. Upper connector, 1202. Bridging cable, 1203. Outer sleeve, 1204. Circuit board, 1205. Protective tube, 1206. Motor, 1207. Reducer, 1208. Sealing shaft, 1209. Switch sleeve, 1210. Lower connector. Detailed Implementation

[0031] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. 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 this invention pertains.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0033] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0034] Example 1

[0035] like Figure 2 As shown, a hydraulic transmission connector includes a cable protection groove 501, a connecting hole 502, a sealing pin 503, and a hydraulic transmission body 504. The cable protection groove 501 is provided on one side of the hydraulic transmission body 504, and the connecting hole 502 is provided on the other side. The sealing pin 503 is provided below the connecting hole, and the pressure transmission cable 8 is sealed to the connecting hole 502 through the sealing pin 503.

[0036] Example 2

[0037] like Figure 3 As shown, a hydraulic drainage device includes a one-way valve seat 1001, a valve ball 1002, an intermediate sleeve 1003, a sealing ring 1004, a balance hole 1005, a sealing plunger 1006, a pressure-regulating shear pin 1007, a lower connector 1008, and a load-bearing rod 1009. The valve seat 1001, intermediate sleeve 1003, and lower connector 1008 are sequentially connected by threads to form an external assembly. The valve ball 1002, sealing ring 1004, sealing plunger 1006, and load-bearing rod 1009 are sequentially placed within the external assembly. The pressure-regulating shear pin 1007 is fixed to the lower connector 1008 through a threaded hole, and the pressure-regulating shear pin 1007 also fixes the valve ball 1002, sealing ring 1004, sealing plunger 1006, and load-bearing rod 1008 placed within the external assembly. The intermediate sleeve 1003 is provided with symmetrically distributed balance holes 1005.

[0038] When the internal pressure reaches 20MPa, the constant pressure shear pin 1007 cuts off, the sealing plunger 1006 and the load-bearing rod 1008 move down, the valve seat 1001 and the valve ball 1002 resume their fit so that the liquid above them can no longer flow down, and at the same time the sealing ring 1004, the sealing plunger 1006 and the intermediate sleeve 1003 lose their sealing fit and the balance hole 1005 is connected inside and outside.

[0039] Example 3

[0040] like Figure 4As shown, the control device 12 includes an upper joint 1201, a bridge cable 1202, an outer sleeve 1203, a circuit board 1204, a protective tube 1205, a motor 1206, a speed reducer 1207, a sealed shaft 1208, a switch sleeve 1209 and a lower joint 1210. The circuit board 1204, the motor 1206, the speed reducer 1207 and the sealed shaft 1208 are sequentially placed in the protective tube 1205, the bridge cable 1202 is sealed from the protective tube 1205 by a compression cap and bridges the upper joint 1201, the bridge cable 1202 transmits signal instructions to the circuit 1204 board, the circuit board 1204 controls the forward and reverse rotation of the motor 1206, the rotational motion output by the motor 1206 is converted into axial linear motion of the sealed shaft, and the axial linear motion of the sealed shaft drives the opening and closing of the switch sleeve 1209.

[0041] Embodiment 4

[0042] As Figure 1 shown, the offshore oilfield multilayer real-time separate layer control safety production pipe string includes a safety valve 1, a cable passing packer 2, a signal cable 3, an electric pump cable 4, a hydraulic transmission joint 5, a check valve 6, an electric pump hanging weight cylinder 7, a pressure transmission pipeline 8, an electric pump unit 9, a hydraulic drainage device 10, a compression type packer 11, a control device 12, a tubing 13 and a thread plug 14. The electric pump hanging weight cylinder 7 is provided with the electric pump unit 9, and the electric pump unit 9 is connected to the electric pump cable 4 on the outside; the upper end of the electric pump hanging weight cylinder 7 is sequentially provided with the safety valve 1, the cable passing packer 2, the hydraulic transmission joint 5 and the check valve 6 from top to bottom through the tubing 13; the lower end of the electric pump hanging weight cylinder is sequentially provided with the hydraulic transmission joint 5, the hydraulic drainage device 10, the compression type packer 11, the control device 12 and the thread plug 14 from top to bottom through the tubing 13; the control device 12 is connected in series through the signal cable 3 on the outside; the upper hydraulic transmission joint 5 and the lower hydraulic transmission joint 5 are connected through the pressure transmission pipeline 8, and the pressure transmission pipeline 8 is arranged on the outside of the electric pump hanging weight cylinder 7, thereby completing the hydraulic transmission of the compression type packer 11 below the electric pump unit through the pressure transmission pipeline 8 and realizing the complete setting and separation of the once-pressurized separate layer control safety production pipe string packer.

[0043] The hydraulic transmission joint 5, the hydraulic drainage device 10 and the control device 12 are respectively shown in Embodiment 1, Embodiment 2 and Embodiment 3.

[0044] The working principle of the offshore oilfield multilayer real-time separate layer control safety production pipe string, i.e., the use method, is as follows:

[0045] In field use, the Figure 1The multi-layer real-time separated layer control production safety string of offshore oilfield is connected in sequence on the ground, the built-in switch sleeve 1209 of the control and measurement device 12 of each layer is controlled to be in the open state through the signal cable 3, the internal and external pressures of the oil pipe 13 are kept in the same pressure system, and the compression type packer 11 is prevented from being accidentally set early due to pressure influence. After the string is completely lowered to the designed position in the well, the built-in switch sleeve 1209 of the control and measurement device 12 of each layer is controlled to be in the closed state through the signal cable 3, the oil pipe is pressed from the wellhead, the liquid pressure acts on the cable packer 2, and the liquid pressure acts on the compression type packer 11 through the hydraulic transmission connector 5 and the pressure transmission pipeline 8, so that all the packers of the string are set. When the pressure continues to rise to 20 MPa, the built-in pressure shear pin 1007 of the hydraulic flow guiding device 10 is sheared, the sealing plunger 1006 and the load rod 1009 move downward, the valve seat 1001 and the valve ball 1002 restore cooperation so that the liquid above cannot continue to flow downward, and the sealing rubber ring 1004, the sealing plunger 1006 and the middle sleeve 1003 lose the sealing cooperation of the balance hole 1005.

[0046] During normal production, the built-in switch sleeve 1209 of the control and measurement device 12 of each layer is controlled to be in the open state through the signal cable 3, the formation produced liquid enters the oil pipe 13 through the control and measurement device 12, flows upward to the hydraulic flow guiding device 10 and then flows out to the outside of the string from the balance hole 1005, and then enters the electric pump unit 9 through the electric pump suspension cylinder 7 and is lifted to the ground, and according to the geological development plan, the real-time control of each control and measurement device 12 can also be carried out. Thus, the problem of real-time control of multi-layer section of the suspended separated layer string of the electric pump lifting well with large scale used in offshore is solved, a plurality of control and measurement devices are connected in series by using one signal cable, the number of layers is controlled, the efficiency is high, the construction is convenient, the method is reliable, safe, has high success rate and wide application prospect.

[0047] The above embodiment is a preferred embodiment of the present application, but the embodiment of the present application is not limited to the above embodiment, and any change, modification, replacement, combination and simplification without departing from the spirit and principle of the present application should be equivalent replacement method and should be included in the protection scope of the present application.

Claims

1. A kind of offshore oilfield multilayer real-time separate layer safety production control pipe column, it is characterized in that, The electric pump hanging weight cylinder, the electric pump unit, the electric pump cable, the signal cable, the safety valve, the cable passing packer, the hydraulic transmission connector, the one-way valve, the hydraulic drainage device, the compression type packer, the control device, the oil pipe, the plug, and the pressure transmission pipeline are sequentially connected from top to bottom. The electric pump unit is placed in the electric pump hanging weight cylinder, the electric pump cable is connected to the outside of the electric pump unit, and the control devices are connected in series through the signal cable. The electric pump hanging weight cylinder has a double-layer structure of an inner tube and an outer tube, the electric pump unit is arranged on the inner tube, and the outer tube of the electric pump hanging weight cylinder is provided with symmetrical liquid inlet grooves to provide a liquid flow channel for the electric pump unit. The hydraulic transmission connector comprises a cable protection groove, a communication hole, a sealing press nail and a hydraulic transmission body. The hydraulic drainage device comprises a valve seat, a valve ball, an intermediate sleeve, a sealing rubber ring, a sealing plunger, a constant pressure shear nail, a lower connector and a bearing rod.

2. The safety production control string for offshore oilfield multilayer real-time separate layer measurement according to claim 1, characterized in that, The cable passing hole is arranged at the upper end of the electric pump hanging weight cylinder.

3. The safety production control pipe column for offshore oilfield multilayer real-time separate layer measurement according to claim 1, characterized in that, The intermediate sleeve is provided with symmetrically distributed balance holes.

4. The safety production control string for offshore oilfield multilayer real-time separate layer measurement according to claim 1, characterized in that, The control device comprises an upper connector, a bridging cable, an outer sleeve, a circuit board, a protection tube, a motor, a speed reduction device, a sealing shaft, a switch sleeve and a lower connector.

5. The use of the offshore oilfield multilayer real-time separate layer safety production string of claim 4, characterized in that, The following steps are included: The built-in switch sleeve of the control device of each layer is controlled to be in an open state through the signal cable to keep the pressure inside and outside the oil pipe in the same pressure system and prevent the compression type packer from being prematurely set due to pressure. After the pipe string is completely lowered to the designed position in the well, the built-in switch sleeve of the control device of each layer is controlled to be in a closed state through the signal cable, the oil pipe is pressurized from the wellhead, the liquid pressure acts on the cable passing packer, and the compression type packer is acted on through the hydraulic transmission connector and the pressure transmission pipeline, so that all the packers of the pipe string are set. The pressure continues to rise, the built-in constant pressure shear nail of the hydraulic drainage device is sheared, the sealing plunger and the bearing rod move downward, the valve seat and the valve ball restore cooperation to prevent the liquid above from continuing to flow downward, and the sealing rubber ring, the sealing plunger and the intermediate sleeve lose the sealing cooperation of the balance hole to communicate the inside and outside of the balance hole. In normal production, the built-in switch of the measuring and controlling device of each layer section is in the open state through the signal cable control, the formation produced liquid enters the oil pipe through the measuring and controlling device, flows up to the hydraulic flow guiding device and then flows out to the pipe column from the balance hole, and then enters the electric pump unit through the electric pump suspension cylinder and is lifted to the ground.

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