Open hole segmented well completion soluble fracturing ball and production equipment thereof

Abstract

The utility model discloses an open hole segmented well completion soluble fracturing ball and production equipment thereof, and relates to the technical field of petroleum engineering well completion, and the open hole segmented well completion soluble fracturing ball is characterized in that the open hole segmented well completion soluble fracturing ball adopts a structure of a soluble ball core and an outer protective layer. The soluble ball core is made of a high-pressure-resistant, high-temperature-resistant and easy-to-corrode material, the outer protection layer is made of a high-temperature-resistant, high-pressure-resistant and corrosion-resistant polytetrafluoroethylene nano particle modified phenolic resin material, and by limiting the thickness of the outer protection layer, the pressure stabilization duration of the open hole segmented well completion soluble fracturing ball under the given temperature, pressure and acid environment is limited, so that the open hole segmented well completion soluble fracturing ball is stable in pressure stability. The soluble fracturing ball for open hole segmented well completion can be quickly dissolved after meeting the fracturing requirement.

Description

Technical Field

[0001] The utility model relates to the technical field of well completion in petroleum engineering, and more specifically, to a soluble fracturing ball for open-hole segmented well completion and production equipment thereof. Background Art

[0002] Shunbei Oilfield is an ultra-deep (>7500m), high-temperature (160-180℃), high-pressure (90-140MPa), and highly heterogeneous fault-karst oil and gas reservoir. In the early stage of development, the completion technology was single, and the conventional leakage well induced blowout production or general acid fracturing completion technology did not fully utilize the reservoir, resulting in low single well production and poor development efficiency; this was mainly manifested in the weak correlation of fault zone distribution, acid loss to weak points, ineffective transformation of favorable sweet spots, and only 70% success rate of sliding sleeves. In view of the heterogeneous characteristics of the reservoir, the ultra-deep horizontal well open hole segmented completion technology currently used can effectively release the production capacity of ultra-deep large fault zones, meet the needs of reservoir development, and achieve the goal of long-term stable production. Soluble fracturing balls play a key role in open hole staged completion technology. They need to be placed into the well at a predetermined time or depth to block the pipeline or wellbore. Since their dissolution requires certain conditions and time, during the dissolution process of the soluble fracturing balls, high-pressure fluid can be pumped to accumulate pressure at specific locations in the well to form cracks.

[0003] The soluble fracturing balls used in staged fracturing in the current open-hole staged completion technology can withstand a pressure of 70 MPa at 80°C, but their general dissolution time is 10 days or even longer, and their dissolution efficiency is relatively low.

[0004] Based on the above reasons, the utility model provides a soluble fracturing ball for open hole staged completion and its production equipment, which improves the dissolution efficiency of the soluble fracturing ball on the basis of meeting the downhole pressure requirements, so that the soluble fracturing ball can be quickly dissolved after the cracks are formed, so as to facilitate subsequent operations. Utility Model Content

[0005] To achieve the above purpose, the utility model provides the following technical solution: a soluble fracturing ball for open hole staged completion, comprising a soluble ball core and an outer protective layer, wherein the soluble ball core is any one of a wooden ball core, a plastic ball core, a fiber ball core, a porous ceramic ball core, an aluminum ball core, an aluminum alloy ball core, a magnesium ball core, and a magnesium alloy ball core. The outer protective layer is uniformly attached to the surface of the soluble ball core, and the outer protective layer is a polytetrafluoroethylene nanoparticle modified phenolic resin material layer.

[0006] The utility model is further configured as follows: corrosion-resistant and high-temperature-resistant rubber particles are evenly distributed in the outer protective layer.

[0007] The utility model is further configured as follows: the particle size of the rubber particles is smaller than or equal to the particle size of the polytetrafluoroethylene nanoparticles in the polytetrafluoroethylene nanoparticle-modified phenolic resin material layer.

[0008] The utility model is further configured as follows: the rubber particles are any one of fluororubber particles, silicone rubber particles, and polytetrafluoroethylene rubber particles.

[0009] The utility model is further configured as follows: the thickness of the outer protective layer is 0.4-0.6mm.

[0010] The utility model is further configured as follows: the soluble ball core is any one of an aluminum ball core, an aluminum alloy ball core, a magnesium ball core, and a magnesium alloy ball core.

[0011] The utility model is further configured to include an inner protective layer, which is uniformly attached between the outer protective layer and the soluble ball core, and is used to improve the corrosion resistance of the soluble ball core. The inner protective layer is any one of a chemical conversion layer, an anodized layer, a metal coating, and a diffusion coating.

[0012] The utility model is further configured as follows: the chemical conversion layer is any one of a chromate conversion layer, a phosphate conversion layer, a phosphate-permanganate conversion layer, and a rare earth conversion layer.

[0013] The utility model is further configured as follows: the anodized layer is a micro-arc anodized layer.

[0014] The utility model is further configured as follows: the soluble ball core is a magnesium alloy ball core.

[0015] The utility model is further configured as follows: the soluble ball core is a magnesium-aluminum alloy ball core.

[0016] The utility model is further configured as follows: the inner protective layer is a chemical conversion layer.

[0017] The utility model is further configured as follows: the thickness of the inner protective layer is 1 μm-5 μm.

[0018] The utility model is further configured as follows: the open hole segmented completion soluble fracturing balls are divided into different grades according to diameter from large to small.

[0019] The utility model also provides an open hole segmented well completion soluble fracturing ball production device: it is used to produce the above-mentioned open hole segmented well completion soluble fracturing ball, including a device for coating polytetrafluoroethylene nanoparticle modified phenolic resin material on the surface of the soluble ball core.

[0020] In summary, compared with the prior art, the utility model has the following beneficial effects: the open-hole staged completion soluble fracturing ball in the utility model adopts a "soluble ball core + outer protective layer" structure. The soluble ball core is made of a high-pressure, high-temperature, and easily corrosive material, and the outer protective layer is made of a high-temperature, high-pressure, and corrosion-resistant polytetrafluoroethylene nanoparticle-modified phenolic resin material. By limiting the thickness of the outer protective layer, the pressure stability time of the open-hole staged completion soluble fracturing ball under a given temperature, pressure, and acidic environment is limited, so that the open-hole staged completion soluble fracturing ball can be quickly dissolved after meeting the fracturing requirements. At the same time, the utility model also adds rubber particles to the outer protective layer, which increases the toughness of the outer protective layer and further improves the protective effect of the outer protective layer on the soluble ball core during entering the well and bearing pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of a soluble fracturing ball for open hole staged completion;

[0022] Figure 2 for Figure 1 A magnified schematic diagram of area A in the middle.

[0023] In the figure: 1. soluble core; 2. inner protective layer; 3. outer protective layer. DETAILED DESCRIPTION

[0024] The technical solution of the utility model will be clearly described below in conjunction with the accompanying drawings. Obviously, the described embodiments are not all embodiments of the utility model. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0025] It should be noted that the terms "center", "up", "down", "horizontal", "left", "right", "front", "back", "lateral", "longitudinal", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0026] Example

[0027] like Figure 1-2As shown, it is a schematic diagram of the structure of the open-hole staged completion soluble fracturing ball in a preferred embodiment of the utility model, and the open-hole staged completion soluble fracturing ball includes a soluble ball core 1 and an outer protective layer 3. The soluble ball core 1 has the performance of high temperature resistance and high pressure resistance, and is any one of a wooden ball core, a plastic ball core, a fiber ball core, a porous ceramic ball core, an aluminum ball core, an aluminum alloy ball core, a magnesium ball core, and a magnesium alloy ball core. The outer protective layer 3 is uniformly attached to the surface of the soluble ball core 1, and the outer protective layer 3 is a polytetrafluoroethylene nanoparticle modified phenolic resin material layer, which has the performance of high pressure resistance and high temperature resistance, and can also effectively improve the corrosion resistance of the soluble ball core 1. By controlling the thickness of the polytetrafluoroethylene nanoparticle modified phenolic resin material layer, the pressure stability time of the open-hole staged completion soluble fracturing ball under a given temperature, pressure, and acidic environment can be controlled.

[0028] Specifically, corrosion-resistant and high-temperature-resistant rubber particles are evenly distributed in the outer protective layer 3. The rubber particles can effectively enhance the toughness of the outer protective layer 3, and can further improve the protective effect of the outer protective layer 3 on the soluble ball core during the well entry and pressure-bearing process. In this embodiment, the rubber particles are any one of fluororubber particles, silicone rubber particles, and polytetrafluoroethylene rubber particles.

[0029] Specifically, the particle size of the rubber particles is smaller than or equal to the particle size of the polytetrafluoroethylene nanoparticles in the polytetrafluoroethylene nanoparticle modified phenolic resin material layer, so as to reduce the influence of the rubber particles on the surface roughness of the polytetrafluoroethylene nanoparticle modified phenolic resin material layer.

[0030] Specifically, the outer protective layer 3 has a thickness of 0.4-0.6 mm, and will age, bulge, and peel off after 6-10 hours in a high temperature environment.

[0031] Specifically, the soluble ball core 1 is any one of an aluminum ball core, an aluminum alloy ball core, a magnesium ball core, and a magnesium alloy ball core. The metal ball core is easily corroded, and the metal ball core has a low bonding strength with the polytetrafluoroethylene nanoparticle modified phenolic resin material layer, and is easily detached under the combined action of a high temperature environment and the impact of a strong corrosive medium, which helps to accelerate the dissolution of the soluble fracturing ball for open hole staged completion. The soluble ball core 1 is preferably a magnesium alloy ball core, which generates less pollution during the dissolution process and meets environmental protection requirements, and the magnesium alloy ball core has a low density and is easy to transport. On this basis, this embodiment selects a magnesium-aluminum alloy ball core from the magnesium alloy ball core as the soluble ball core 1 from a comprehensive consideration of temperature resistance, material strength, processing performance, and degradation ability.

[0032] This embodiment further includes an inner protective layer 2, which is uniformly attached between the outer protective layer 3 and the soluble core 1. The inner protective layer 2 is used to improve the corrosion resistance of the soluble core 1 and reduce the possibility of the soluble core 1 being dissolved during the period when the open hole staged completion soluble fracturing ball maintains a stable pressure in a given temperature environment, pressure environment and acidic environment. The inner protective layer 2 is any one of a chemical conversion layer, an anodic oxide layer, a metal coating, and a diffusion coating.

[0033] The chemical conversion layer is a layer of oxide or metal compound passivation film formed on the surface of the metal ball core after the metal ball core is immersed in a chemical treatment solution. The chemical conversion layer is preferably any one of a chromate conversion layer, a phosphate conversion layer, a phosphate-permanganate conversion layer, and a rare earth conversion layer. The anodic oxide layer is an oxide film formed on the surface of the metal ball core by electrochemical oxidation. The anodic oxide layer is preferably a micro-arc anodic oxide layer. The metal coating is a layer of metal or alloy film coated on the surface of the metal ball core by a physical method. The diffusion coating is a coating with a porous structure formed on the surface of the metal ball core. The inner protective layer 2 in this embodiment is a chemical conversion layer, and the thickness of the inner protective layer 2 is 1μm-5μm.

[0034] Specifically, the open hole staged completion soluble fracturing balls are classified into different grades according to diameter from large to small. The open hole staged completion soluble fracturing balls of different diameters can better control the expansion direction and range of the cracks in the well, thereby forming a more complex branched fracture network. At the same time, the operation of grading by diameter also contributes to the standardized production of open hole staged completion soluble fracturing balls.

[0035] This embodiment also provides an open hole staged completion soluble fracturing ball production device, which is used to produce the above-mentioned open hole staged completion soluble fracturing ball, and includes a device for coating a polytetrafluoroethylene nanoparticle modified phenolic resin material on the surface of the soluble ball core 1.

[0036] Taking a well in ultra-deep carbonate rock fracture and dissolution pore reservoir as an example, the well was completed using the above-mentioned open hole segmented completion soluble fracturing ball. The construction well section was 7564.0m-8659.11m, and fracturing was carried out in three sections. The diameter of the open hole segmented completion soluble fracturing ball used in each section was different. The diameter of the open hole segmented completion soluble fracturing ball gradually decreased along the well section from small to large distance from the wellhead. The difference of the open hole segmented completion soluble fracturing ball in adjacent sections was 6.35mm. The total fluid volume after the well was completed was 2535m 3 , maximum displacement 10.3m 3 / min, the maximum pump pressure is 134.8MPa, and the pump stop pressure is 11.5MPa. After using a 13mm oil nozzle to calculate the production of this well, it is known that the natural gas test production of this well is 99.87×104m3 under the condition of oil pressure of 52.83MPa 3 / d, daily oil production is 288m3 , converted into oil and gas equivalent of 1017t / d.

[0037] In summary, the present embodiment provides a soluble fracturing ball for open-hole staged well completion and its production equipment, wherein the soluble fracturing ball for open-hole staged well completion adopts the structure of "soluble ball core 1 + outer protective layer 3". The soluble ball core 1 is made of a high-pressure, high-temperature and easily corrosive material, and the outer protective layer 3 is made of a polytetrafluoroethylene nanoparticle-modified phenolic resin material that is resistant to high temperature, high pressure and corrosion. By limiting the thickness of the outer protective layer 3, the pressure stability time of the soluble fracturing ball for open-hole staged well completion under a given temperature, pressure and acidic environment is limited, so that the soluble fracturing ball for open-hole staged well completion can be quickly dissolved after meeting the fracturing requirements. At the same time, the present embodiment also adds rubber particles to the outer protective layer 3, which increases the toughness of the outer protective layer 3 and further improves the protective effect of the outer protective layer 3 on the soluble ball core during entering the well and bearing pressure.

[0038] 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 soluble fracturing ball for open hole staged completion, characterized by: The invention comprises a soluble ball core (1) and an outer protective layer (3), wherein the soluble ball core (1) is any one of a plastic ball core, a porous ceramic ball core, an aluminum ball core, an aluminum alloy ball core, a magnesium ball core, and a magnesium alloy ball core; the outer protective layer (3) is uniformly attached to the surface of the soluble ball core (1), and the outer protective layer (3) is a polytetrafluoroethylene nanoparticle modified phenolic resin material layer; the thickness of the outer protective layer (3) is 0.4-0.6 mm; and the invention also comprises an inner protective layer (2), wherein the inner protective layer (2) is uniformly attached between the outer protective layer (3) and the soluble ball core (1), and the inner protective layer (2) is used to improve the corrosion resistance of the soluble ball core (1), and the inner protective layer (2) is any one of a chemical conversion layer, an anodic oxidation layer, a metal coating, and a diffusion coating.

2. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The chemical conversion layer is any one of a chromate conversion layer, a phosphate conversion layer, a phosphate-permanganate conversion layer, and a rare earth conversion layer.

3. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The anodized layer is a micro-arc anodized layer.

4. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The soluble ball core (1) is a magnesium alloy ball core.

5. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The soluble ball core (1) is a magnesium-aluminum alloy ball core.

6. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The inner protective layer (2) is a chemical conversion layer.

7. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The inner protective layer (2) has a thickness of 1 μm-5 μm.

8. The open hole staged completion soluble fracturing ball according to claim 1, characterized in that: The open hole staged completion soluble fracturing balls are divided into different grades according to diameter from large to small.

9. An open hole staged completion soluble fracturing ball production device, characterized by: The open hole staged completion soluble fracturing ball production equipment is used to produce the open hole staged completion soluble fracturing ball as claimed in claim 1, and comprises a device for coating a polytetrafluoroethylene nanoparticle modified phenolic resin material on the surface of the soluble ball core (1).

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