Composite material electric heating rod body structure for oil field

Abstract

The utility model belongs to the field of oil field application, and relates to a composite material electric heating rod body structure for an oil field, which is composed of a composite material supporting inner core, an inner layer braided copper wire gauze, a carbon fiber electric heating wire layer and an outer layer braided copper wire gauze. According to the heating rod, the flexible carbon fiber woven mesh serves as an electric heating carrier, so that the heating rod has high breaking force. In addition, the heating rod is wrapped by a plurality of insulating layers, so that the insulating property of the heating rod meets the IP58 protection grade requirement, and the sealing performance is excellent.

Description

Technical Field

[0001] The utility model belongs to a sucker rod product in the field of oil field use, and relates to a composite material sucker rod structure with an electric heating function. Background Art

[0002] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the utility model, and shall not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to ordinary technicians in this field.

[0003] The Fuyu oil layer is mainly composed of delta distributary plain subphase deposits, with poor sand body stability and poor oil layer connectivity. According to the analysis of the measured formation temperature data of the Fuyu oil layer, a waxing section is formed within the range of 800 meters to the wellhead, which is deeper than the waxing position of the oil wells in the Sapugao oil layer. It is reported that 25 oil wells in the Fuyu oil layer in a certain well area were put into production. Affected by the "deep well, oil viscosity, and low production" factors of the Fuyu oil layer, some oil wells frequently got stuck, and the pump rate was less than 90% in most months, which seriously affected the production capacity. Because the waxing point of the Fuyu oil well is deep and the water content is low, the conventional hot washing requirements are higher than those of other blocks. The single-well hot washing displacement is 9m 3 / h~12m 3 / h, hot washing time 3h, average hot washing cycle 28 days, there are problems such as short hot washing cycle, poor hot washing effect and long hot washing time. In order to solve the problem of frequent wax sticking in oil wells, 14 wells of oil pipe electric heating technology and 39 wells of oil pipe electric heating belt technology were applied, which played a certain role in wax removal and prevention, but there was inadaptability in the process. The main performance of oil pipe electric heating technology is that when the liquid level is at the wellhead, short circuit conduction is prone to occur, and the equipment has high energy consumption, with a daily power consumption of 480kWh. The heated part is mainly the annular space of the oil casing. The heating effect in the oil pipe is not good. When heated to the same temperature, the energy consumption is high. The main performance of oil pipe electric heating belt technology is that the equipment is easy to be damaged during operation. During operation, tools such as groove protection tie bands need to be removed, which has a large workload and a long time. There is also a problem of high equipment energy consumption, with a daily power consumption of 520kWh. At the same time, there are also problems such as the width of the heating belt is 3cm, only one side can be heated, and the heating area is small.

[0004] Carbon fiber is a flexible electric heating material with good electrical conductivity, which can effectively reduce operating energy consumption. In addition, the carbon fiber continuous electric heating rod can be put in or pulled out at one time during operation, and has good tensile resistance, corrosion resistance, insulation and other properties, which can avoid problems such as cumbersome construction and easy equipment damage, thereby improving the operating efficiency of the oil well and ensuring the efficient development of the Fuyu oil layer. However, the breaking force and insulation performance of the current carbon fiber composite sucker rod still need to be improved. Utility Model Content

[0005] In view of the problems such as the inadaptability of the existing wax cleaning and wax prevention processes, the utility model proposes a carbon fiber composite material continuous electric heating sucker rod structure for oil fields, which includes four parts from the inside to the outside: a composite material support inner core, an inner layer of woven copper wire mesh, a carbon fiber electric heating wire layer, and an outer layer of woven copper wire mesh. The composite material support inner core reinforced with high-strength fibers provides the overall sucker rod strength, and a carbon fiber flexible heating wire is woven on the surface of the composite material support inner core as the heating body. Conductive woven copper wires are twisted on the inner and outer surfaces of the heating wire layer. The interfaces between the support inner core, the inner layer of woven copper wire mesh, the carbon fiber heating wire layer, the outer layer of woven copper wire mesh, and the final sucker rod body surface are all isolated by an insulating coating layer. The twisted copper wire mesh and the carbon fiber heating wire are peeled and connected at the surface position, and the power is provided by the twisted copper wire to achieve power control at different lengths of the concentric cable.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] The first aspect of the utility model provides a composite material electric heating rod structure for oil fields, which comprises, from the inside to the outside: a composite material support inner core, an inner layer of woven copper wire mesh, a carbon fiber electric heating wire layer, and an outer layer of woven copper wire mesh; the composite material support inner core is coated with an inner layer of woven copper wire mesh, the inner layer of woven copper wire mesh is coated with a carbon fiber electric heating wire layer, the carbon fiber electric heating wire layer is coated with an outer layer of woven copper wire mesh, and an insulating layer is arranged between the composite material support inner core, the inner layer of woven copper wire mesh, the carbon fiber electric heating wire layer, the outer layer of woven copper wire mesh, and on the outside of the outer layer of woven copper wire mesh.

[0008] In some embodiments, the composite material support inner core is a solid cylindrical structure with a diameter of 2-10 mm. Preferably, it is prepared by unidirectional pultrusion molding using high-strength glass fiber or high-strength carbon fiber. More preferably, the breaking force is 20-100 KN.

[0009] In some embodiments, the material of the composite material supporting inner core is a carbon fiber resin composite material or a glass fiber resin composite material.

[0010] In some embodiments, in the carbon fiber resin composite material or the glass fiber resin composite material, the glass fiber is high-strength glass fiber, and preferably, the high-strength glass fiber is selected from any one of S1, S2, and S3;

[0011] In some embodiments, the carbon fiber is high-strength carbon fiber, preferably, the high-strength carbon fiber is selected from any one of T300, T700, T800, T1000, and T1200;

[0012] In some embodiments, the resin is selected from any one of thermosetting resins such as unsaturated polyester resin, epoxy resin, phenolic resin, thermosetting polyurethane resin, urea-formaldehyde resin, etc. and is not limited to the above types, and its resin content is controlled within the range of 40-60%.

[0013] In some embodiments, the carbon fiber electric heating wire layer is a single-layer or multi-layer carbon fiber two-dimensional woven mesh structure, wherein the multi-layer carbon fiber two-dimensional woven mesh structure is arranged in a stacked manner, preferably, it is a high-strength or high-modulus carbon fiber two-dimensional woven mesh structure, and more preferably, the carbon fiber two-dimensional woven mesh structure adopts a plain, twill or satin weave.

[0014] In some embodiments, the high-strength carbon fiber is any one of T300, T700, T800, T1000, and T1200;

[0015] In some embodiments, the high modulus carbon fiber may be any type of M40, M40J, M55, M55J, M60, or M60J;

[0016] In some embodiments, high-strength and high-modulus carbon fibers may be used for weaving, or a mixed combination of the two. The mixed ratio may be flexibly adjusted according to design requirements.

[0017] In some embodiments, the heating section length of the carbon fiber electric heating wire layer is 10-50 m, preferably, the power is 20-100 W / m. The heating power of each heating section can be designed by adjusting the parallel length of the carbon fibers.

[0018] In some embodiments, the inner layer braided copper wire mesh and the outer layer braided copper wire mesh each have a coverage area of ​​10-20 mm 2 , thickness is 0.5~1mm.

[0019] In some embodiments, the long-term use temperature of the insulating layer is controlled at 100-150° C., and the material of the insulating layer is EPDM rubber, silicone rubber or fluoroplastic.

[0020] In some embodiments, the thickness of the insulating layer is 0.5-1 mm. Preferably, the breakdown voltage is

[0021] ≥3000V, water and oil resistant.

[0022] Beneficial effects of the utility model

[0023] (1) The utility model adopts a flexible carbon fiber woven mesh as an electric heating carrier, and cooperates with a rigid composite material to support the inner core. The overall sucker rod has a high breaking force that can reach more than 20KN, and the average breaking force can reach about 40KN.

[0024] (2) The utility model adopts a multi-layer insulating coating to effectively isolate the carbon fiber electric heating wire, the inner and outer braided copper wire mesh and the outer surface of the rod, ensuring that the insulation performance meets the IP58 protection level requirements. The sealing performance is tested by boiling water and immersion in water with electric heating, and there is no short circuit.

[0025] (3) The utility model has a simple structure, strong practicability and is easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.

[0027] Figure 1 The utility model is a schematic diagram of the overall structure of the composite material electric heating rod structure for oil fields.

[0028] Among them, 1. composite material supporting inner core, 2. inner layer woven copper wire mesh, 3. carbon fiber electric heating wire layer, 4. outer layer woven copper wire mesh. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0030] Terminology explanation:

[0031] “Carbon fiber two-dimensional woven mesh structure” refers to: a two-dimensional mesh structure woven from carbon fibers.

[0032] “Inner layer braided copper wire mesh” or “outer layer braided copper wire mesh” refers to: a mesh structure woven from copper wires.

[0033] "T300, T700, T800, T1000, T1200" are all specifications and models of high-strength carbon fibers available on the market.

[0034] "M40, M40J, M55, M55J, M60, M60J" are all specifications of commercially available high modulus carbon fibers.

[0035] "S1, S2 or S3" are all specifications of commercially available high-strength glass fibers.

[0036] A carbon fiber composite material continuous electric heating sucker rod structure for oil fields, the structure includes four parts from the inside to the outside: a composite material support inner core, an inner layer of braided copper wire mesh, a carbon fiber electric heating wire layer, and an outer layer of braided copper wire mesh. The composite material support inner core reinforced with high-strength fibers provides the overall sucker rod strength, a carbon fiber flexible heating wire is woven on the surface of the support inner core as the heating body, conductive braided copper wires are twisted on the inner and outer surfaces of the heating wire, and the interfaces between the support inner core, the inner layer of braided copper wire mesh, the carbon fiber heating wire layer, the outer copper wire mesh, and the final sucker rod body are isolated by an insulating coating layer, the twisted copper wire mesh and the carbon fiber heating wire are stripped and connected at the surface, and power is provided by twisted copper wires to achieve power control at different lengths of the concentric cable.

[0037] The high-strength fiber-reinforced composite material support inner core is prepared by unidirectional pultrusion molding using high-strength glass fiber or high-strength carbon fiber. The diameter of the support inner core is controlled within the range of 2-10 mm, and the breaking force is controlled within the range of 20-100 KN.

[0038] The glass fiber used for the high-strength fiber-reinforced composite material supporting inner core may be high-strength type S1, S2 or S3, or any type of T300, T700, T800, T1000, T1200.

[0039] The resin matrix of the supporting inner core can be any type of thermosetting resin such as unsaturated polyester resin, epoxy resin, phenolic resin, thermosetting polyurethane resin, urea-formaldehyde resin, etc. and is not limited to the above types, and its resin content is controlled within the range of 40-60%.

[0040] The carbon fiber flexible heating wire woven on the surface of the supporting inner core can be composed of a two-dimensional woven mesh structure of high-strength or high-modulus carbon fiber, wherein the high-strength carbon fiber can be any type of T300, T700, T800, T1000, and T1200, and the high-modulus carbon fiber can be any type of M40, M40J, M55, M55J, M60, and M60J. The two fibers can be woven in a mixed combination, and the mixing ratio can be flexibly adjusted according to design requirements.

[0041] The high-strength or high-modulus carbon fiber two-dimensional woven mesh structure can be in the form of plain, twill or satin weaving, and the woven mesh can be arranged in a single layer or in a multi-layer stacked arrangement.

[0042] The heating section length of the braided carbon fiber flexible heating wire on the support inner core surface is controlled within the range of 10 to 50 m, and the design power is within the range of 20-100 W / m. The heating power of each heating section can be designed by adjusting the parallel length of the carbon fiber.

[0043] The inner and outer layers of the braided copper wire mesh have a coverage area of ​​10-20 mm per layer. 2 , the thickness is controlled within the range of 0.5 to 1 mm.

[0044] The insulation coating layer has a long-term use temperature controlled at 100-150°C and can be made of any one of EPDM rubber, silicone rubber or fluoroplastics. Its thickness is controlled within the range of 0.5-1mm, meets the breakdown voltage of 3000V, and is water-resistant and oil-resistant.

[0045] The present invention will be further described in detail below in conjunction with specific embodiments. It should be noted that the specific embodiments are intended to explain the present invention rather than to limit it.

[0046] Example 1

[0047] The composite material support core 1 is made of high-strength S1 glass fiber composite epoxy resin through unidirectional pultrusion molding. The diameter of the support core 1 is 5mm, the breaking force is in the range of 20-100KN, and the resin content of the support core 1 is 50%. A carbon fiber flexible heating wire layer 3 is woven on the surface of the support core 1 as the heating body. The carbon fiber flexible heating wire layer 3 is composed of a two-dimensional plain weave mesh structure of T700 high-strength carbon fiber and M55J high-modulus carbon fiber mixed in a ratio of 2:1. The heating section length of the heating wire layer 3 is 30m, and the heating power is in the range of 20-100W / m. The inner and outer surfaces of the heating wire layer 3 are twisted with conductive braided copper wires, and the inner and outer braided copper wire meshes 2 and 4 have a coverage area of ​​15mm 2 , thickness is 0.8mm.

[0048] The interfaces between the supporting inner core 1, the inner braided copper wire mesh 2, the carbon fiber heating wire layer 3, the outer braided copper wire mesh 4 and the surface of the final sucker rod body are all isolated with EPDM as an insulating coating layer, and the long-term use temperature is controlled at 100-150°C, with a thickness of 0.8mm. The above constitutes a specific embodiment 1.

[0049] The test results show that the integral sucker rod has a high breaking force, which can reach more than 20KN, and the average breaking force can reach about 40KN. The insulation performance of the integral sucker rod meets the IP58 protection level requirements, and the sealing performance has passed the water boiling and water immersion and electric heating tests without short circuit.

[0050] Example 2

[0051] Composite material support core 1 The support core 1 is made of T800 high-strength carbon fiber composite unsaturated polyester resin through unidirectional pultrusion molding. The diameter of the support core 1 is 6mm, the breaking force is in the range of 20-100KN, and the resin content of the support core 1 is 40%. A carbon fiber flexible heating wire layer 3 is woven on the surface of the support core 1 as the heating body. The carbon fiber flexible heating wire layer 3 is composed of a two-dimensional twill weave mesh structure of T800 high-strength carbon fiber and M55 high modulus carbon fiber mixed in a ratio of 3:1. The heating section length of the heating wire layer 3 is 40m, and the heating power is in the range of 20-100W / m. Conductive braided copper wires are twisted on the inner and outer surfaces of the heating wire layer 3, and the coverage area of ​​the inner and outer braided copper wire meshes 2 and 4 is 18mm 2 , thickness is 0.8mm.

[0052] Silicon rubber is used as an insulating coating layer for isolation between the supporting inner core 1, the inner braided copper wire mesh 2, the carbon fiber heating wire layer 3, the outer braided copper wire mesh 4 and the surface of the final sucker rod body, and the long-term use temperature is controlled at 100-150°C and the thickness is 0.5mm. The above constitutes a specific embodiment 2.

[0053] The test results show that the integral sucker rod has a high breaking force, which can reach more than 20KN, and the average breaking force can reach about 40KN. The insulation performance of the integral sucker rod meets the IP58 protection level requirements, and the sealing performance has passed the water boiling and water immersion and electric heating tests without short circuit.

[0054] Example 3

[0055] The composite material support core 1 is made of high-strength S2 glass fiber composite epoxy resin through unidirectional pultrusion molding. The diameter of the support core 1 is 5mm, the breaking force is in the range of 20-100KN, and the resin content of the support core 1 is 50%. A carbon fiber flexible heating wire layer 3 is woven on the surface of the support core 1 as the heating body. The carbon fiber flexible heating wire layer 3 is composed of a two-dimensional plain weave mesh structure of T700 high-strength carbon fiber and M55J high modulus carbon fiber mixed in a ratio of 2:1. The heating section length of the heating wire layer 3 is 30m, and the heating power is in the range of 20-100W / m. Conductive braided copper wires are twisted on the inner and outer surfaces of the heating wire layer 3, and the coverage area of ​​the inner and outer braided copper wire meshes 2 and 4 is 10mm 2 , thickness is 0.5mm.

[0056] The interfaces between the supporting inner core 1, the inner braided copper wire mesh 2, the carbon fiber heating wire layer 3, the outer braided copper wire mesh 4 and the surface of the final sucker rod body are all isolated with EPDM rubber as an insulating coating layer, and the long-term use temperature is controlled at 100-150°C, with a thickness of 0.8mm. The above constitutes a specific embodiment 3.

[0057] The test results show that the integral sucker rod has a high breaking force, which can reach more than 20KN, and the average breaking force can reach about 40KN. The insulation performance of the integral sucker rod meets the IP58 protection level requirements, and the sealing performance has passed the water boiling and water immersion and electric heating tests without short circuit.

[0058] Example 4

[0059] The composite material support core 1 is made of T1000 high-strength carbon fiber composite phenolic resin through unidirectional pultrusion molding. The diameter of the support core 1 is 6mm, the breaking force is in the range of 20-100KN, and the resin content of the support core 1 is 40%. A carbon fiber flexible heating wire layer 3 is woven on the surface of the support core 1 as the heating body. The carbon fiber flexible heating wire layer 3 is composed of a two-dimensional satin woven mesh structure made of T1000 high-strength carbon fiber and M40J high modulus carbon fiber mixed in a ratio of 1:1. The heating section length of the heating wire layer 3 is 50m, and the heating power is in the range of 20-100W / m. Conductive braided copper wires are twisted on the inner and outer surfaces of the heating wire layer 3, and the coverage area of ​​the inner and outer braided copper wire meshes 2 and 4 is 20mm 2 , thickness is 1mm.

[0060] Silicon rubber is used as an insulating coating layer for isolation between the supporting inner core 1, the inner braided copper wire mesh 2, the carbon fiber heating wire layer 3, the outer braided copper wire mesh 4 and the surface of the final sucker rod body, and the long-term use temperature is controlled at 100-150°C and the thickness is 1mm. Specific embodiment 4 is constructed by the above.

[0061] The test results show that the integral sucker rod has a high breaking force, which can reach more than 20KN, and the average breaking force can reach about 40KN. The insulation performance of the integral sucker rod meets the IP58 protection level requirements, and the sealing performance has passed the water boiling and water immersion and electric heating tests without short circuit.

[0062] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A composite material electric heating rod structure for oil fields, characterized in that: From the inside to the outside, it includes: a composite material supporting inner core, an inner layer of woven copper wire mesh, a carbon fiber electric heating wire layer, and an outer layer of woven copper wire mesh; the composite material supporting inner core is coated with an inner layer of woven copper wire mesh, the inner layer of woven copper wire mesh is coated with a carbon fiber electric heating wire layer, the carbon fiber electric heating wire layer is coated with an outer layer of woven copper wire mesh, and an insulating layer is arranged between the composite material supporting inner core, the inner layer of woven copper wire mesh, the carbon fiber electric heating wire layer, the outer layer of woven copper wire mesh, and on the outside of the outer layer of woven copper wire mesh.

2. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The composite material support inner core is a solid cylindrical structure with a diameter of 2-10 mm.

3. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The material of the composite material supporting inner core is a carbon fiber resin composite material.

4. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The material of the composite material supporting inner core is glass fiber resin composite material.

5. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The carbon fiber electric heating wire layer is a single-layer or multi-layer carbon fiber two-dimensional woven mesh structure, wherein the multi-layer carbon fiber two-dimensional woven mesh structure is overlapped and arranged.

6. The composite material electric heating rod structure for oil fields according to claim 5, characterized in that: The carbon fiber two-dimensional woven mesh structure adopts a plain, twill or satin weaving form.

7. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The length of the heating section of the carbon fiber electric heating wire layer is 10 to 50 m.

8. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The inner layer braided copper wire mesh and the outer layer braided copper wire mesh each have a coverage area of ​​10-20 mm 2 , thickness is 0.5~1mm.

9. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The material of the insulating layer is EPDM rubber, silicone rubber or fluoroplastic.

10. The composite material electric heating rod structure for oil fields according to claim 1, characterized in that: The thickness of the insulating layer is 0.5-1 mm.

Images