Drillable sand control screen pipe and deep gravel packing sand control method adopting same

Abstract

The invention discloses a drillable sand control screen pipe and a deep gravel packing sand control method adopting the screen pipe. Wherein the drillable sand control screen pipe is a glass fiber reinforced plastic composite material pipe with vertical screen seams, which is prepared by taking epoxy resin as a matrix, taking glass fiber as a reinforcing material and adding an improver at the same time. The drillable sand control screen pipe has the advantages that the drillable sand control screen pipe has the characteristics of being light in self weight, not prone to scaling, capable of being completely drilled and broken and the like, the problem that fishing is difficult after sand control of a long well section machine is effectively solved, the overall operation efficiency is improved, and after the drillable sand control screen pipe is adopted, the single well fishing time is shortened to 5-8 days from 28 days.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field underground construction equipment and application, and particularly relates to a drillable sand control screen pipe and a deep gravel filling sand control method using the screen pipe. Background Art

[0002] At present, the sand control technology for conventional oil wells is relatively mature. The deep gravel packing sand control method is to use large-scale sand addition and variable displacement construction to establish a compacted, large-scale, continuous sand barrier in the near-well area, perforation holes, screen annulus and other areas to meet the sand control needs of conventional wells. However, with the continuous deepening of oil field development, the number of sand-producing oil wells with complex well conditions (wells with a diameter of ﹤100mm, long well sections, and high-mineralization wells) has increased year by year. Therefore, the current mechanical sand control method mainly has the following problems when applied:

[0003] Sand-producing oil wells with variable casing, long well sections, and multiple layers have difficulty in salvaging the sand-proof screen after sand control. For example, the M7-X1 oil well has three sand-proof layers, and the total length of the sand-proof layer section is more than 50 meters. During the later salvage, the steel sand-proof screen is easy to break and difficult to drill, so the salvage time can be as long as 28 days.

[0004] (1) Chinese invention patent application CN201510752899.7 discloses a method for completing a coalbed methane horizontal well using a glass fiber reinforced plastic screen. The method uses a glass fiber reinforced plastic sand control screen for completion and is suitable for lowering a glass fiber reinforced plastic screen into a horizontal well with a large water-to-vertical ratio.

[0005] (2) Chinese invention patent application CN201610755016.2 discloses a variable diameter sand screen. In the natural state, there is a certain gap between two adjacent sand screen segments, and the sand retaining steel plate is located on the inner side of the two adjacent sand screen segments to block the gap. In the variable diameter state, the hinge mechanism expands outward, supporting the split sand screen segments and the sand retaining steel plate to expand radially at the same time, so that the split sand screen segments and the sand retaining steel plates just form a full circle. Adding sand retaining steel plates and hinge mechanisms inside is suitable for multi-layer oil testing technology.

[0006] (3) Chinese invention patent application CN202210285297.5 discloses a sand-proof screen pipe and sand-proof injection and production method for gas wells in gas storage facilities. This method provides a first one-way valve at the lower end of the sand-proof screen pipe body, so that the sand-proof screen pipe has the function of flushing sand and removing blockage. This method is applicable to gas wells. When using the sand-proof screen pipe for production, high-speed flowing gas will not be formed, so it is not applicable to oil wells.

[0007] In summary, the sand control screens that are easy to salvage in the existing technologies are all realized by changing the screen structure. However, due to the complex structure of the sand control screen, the difficulty of on-site operation and the high production cost, they are not suitable for complex sand-producing oil wells. Summary of the invention

[0008] In order to solve the above problems, the object of the present invention is to provide a drillable sand control screen and a deep gravel packing sand control method using the screen.

[0009] In order to achieve the above-mentioned purpose, the drillable sand control screen pipe provided by the present invention is a glass fiber reinforced plastic composite material pipe with vertical screen slots, which is made of epoxy resin as a matrix, glass fiber as a reinforcing material, and an improver. The preparation method is: the surface of the glass fiber is pretreated including degreasing, and then immersed in a mixed solution of epoxy resin and improver, and then evenly wound on the outer surface of the core mold in a spiral manner, and finally cured and demolded to obtain a drillable sand control screen pipe base pipe; then a sheet milling cutter is used to mill a plurality of vertical screen slots set at intervals on the circumferential wall of the above-mentioned drillable sand control screen pipe base pipe, thereby making the drillable sand control screen pipe.

[0010] The mass ratio of the epoxy resin, the glass fiber and the improver is: 30-40: 50-60: 5-10.

[0011] The improver is composed of a diluent, a leveling agent and an anti-settling agent, wherein the diluent is prepared by compounding butyl acetate and cyclohexanone in a ratio of 1:1; the leveling agent is modified acrylate, and the amount used accounts for 0.1-1% of the total amount of the improver; the anti-settling agent is polyolefin, and the amount used accounts for 0.1-1% of the total amount of the improver.

[0012] The winding angle of the glass fiber is 45°.

[0013] The vertical sieve slits have a width of 0.2-0.4 mm, a length of 50-60 mm, and a density of 150-250 slits / m.

[0014] The deep gravel packing sand control method using the drillable sand control screen of the present invention comprises the following steps performed in sequence:

[0015] 1) On the ground, the staff uses a band clamp to connect the drillable sand control screen pipes together in an end-to-end manner to form a sand control pipe string; then install the sand control hand-release tool and the thread plug at the upper and lower ends of the sand control pipe string respectively;

[0016] 2) Slowly lower the sand control pipe string together with the sand control hand-release tool and the screw plug into the casing of the sand-producing oil well until the middle position of the sand control pipe string is aligned with the oil layer, and the upper end of the sand control pipe string is more than 3 meters above the top of the oil layer, and the lower end is more than 3 meters below the bottom of the oil layer;

[0017] 3) Use a pump truck to pump sand-carrying fluid into the tubing for gravel packing. During this process, the pump pressure should be paid attention to in real time. The gravel is filled in the near-wellbore area and the screen annulus by adjusting the pump truck displacement and the filling sand ratio to form a near-wellbore area filling zone and a screen annulus filling zone, and ensure that the top surface of the screen annulus filling zone is located 30 meters above the upper end of the sand prevention tool; then pump in clean water to push the sand-carrying fluid out of the tubing; thus completing the gravel packing process;

[0018] 4) If the sand control pipe column needs to be salvaged in the later stage of oil production, a drill pipe connected to a drill bit is lowered into the casing, and the drill bit is used to drill and grind the sand control pipe column lowered into the sand-producing oil well. The screen pipe debris after drilling will be salvaged with the well repair protection fluid.

[0019] In step 2), the downward movement speed of the sand control pipe string is less than 0.5 m / min.

[0020] The drillable sand control screen and the deep gravel filling sand control method using the screen provided by the present invention have the following beneficial effects: the drillable sand control screen has the characteristics of light weight, not easy to scale, and can be completely drilled and broken, which effectively solves the problem of difficult salvage after mechanical sand control in long well sections and improves the overall operation efficiency. After using the drillable sand control screen, the salvage time of a single well is reduced from 28 days to 5-8 days. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the drillable sand control screen structure provided by the present invention.

[0022] Figure 2 A schematic diagram of the construction process of a deep gravel packing sand control method using a drillable sand control screen provided by the present invention. DETAILED DESCRIPTION

[0023] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Embodiment 1:

[0025] like Figure 1 As shown, the drillable sand control screen provided in this embodiment is a glass fiber reinforced plastic composite material pipe with vertical screen slots, which is made of epoxy resin as a matrix, glass fiber as a reinforcing material, and an improver; the mass ratio of the epoxy resin, glass fiber and improver is 37:55:8. The improver is composed of a diluent, a leveling agent and an anti-settling agent, wherein the diluent is compounded with butyl acetate and cyclohexanone in a ratio of 1:1; the leveling agent is modified acrylate, and the amount is 0.1% of the total amount of the improver; the anti-settling agent is polyolefin, and the amount is 0.2% of the total amount of the improver.

[0026] The preparation method is as follows: pre-treat the surface of the glass fiber including degreasing, then immerse it in a mixture of epoxy resin and improver, and then evenly wind it on the outer surface of the core mold in a spiral manner. The winding angle of the glass fiber is 45°. When the thickness reaches 8mm, solidify and demould to obtain a drillable sand screen base pipe; then use a sheet milling cutter to mill a plurality of vertical screen slots set at intervals on the circumferential wall of the drillable sand screen base pipe, thereby making a drillable sand screen. The drillable sand screen has a length of 4m, an outer diameter of 78mm, and an inner diameter of 62mm; the width of the vertical screen slot is 0.3mm, the length is 56mm, and the density is 200 per meter.

[0027] like Figure 2 As shown, the deep gravel packing sand control method using the drillable sand control screen comprises the following steps performed in sequence:

[0028] 1) On the ground, the staff uses a band clamp to connect the drillable sand control screen pipes together in an end-to-end manner to form a sand control pipe column 3; then install the sand control hand-release tool 2 and the wire plug 4 at the upper and lower ends of the sand control pipe column 3 respectively;

[0029] 2) Slowly lower the sand control pipe string 3 together with the sand control hand-release tool 2 and the wire plug 4 into the casing 5 in the sand-producing oil well at a lowering speed of 0.2 m / min to prevent the sand control pipe string 3 from colliding with the casing 5 due to excessive lowering speed, thereby causing breakage, until the middle position of the sand control pipe string 3 is aligned with the oil layer 6, and the upper end of the sand control pipe string 3 is 3.5 meters higher than the top of the oil layer 6, and the lower end is 3.5 meters lower than the bottom of the oil layer 6;

[0030] 3) Use a pump truck to pump sand-carrying fluid into the oil pipe 1 for gravel packing. During this process, the pump pressure should be paid attention to in real time. By adjusting the pump truck displacement and the filling sand ratio, the gravel is filled in the near-wellbore area and the screen annulus to form a near-wellbore area filling zone A and a screen annulus filling zone B. In this embodiment, the pump truck displacement is required to be 1.6m 3 / min or less, the filling sand ratio is set to 5%. If the pump pressure remains stable for a period of time, the sand ratio is increased step by step, and 4-6m3 of sand is added in each stage. 3 , the total amount of sand added is 20m 3 and ensure that the top surface of the screen annulus filling zone B is located 30 meters above the upper end of the sand control tool; then pump in clean water to push the sand-carrying liquid out of the oil pipe 1; thus completing the gravel filling process;

[0031] 4) If the sand control pipe column 3 needs to be salvaged in the later stage of oil production, a drill pipe connected with a drill bit is lowered into the casing 5, and the drill bit is used to drill and grind the sand control pipe column 3 lowered into the sand-producing oil well, and the screen pipe debris after drilling will be salvaged with the well repair protection fluid.

[0032] The drillable sand control screen provided by the embodiment of the present invention is used to carry out sand control operations on the sand-producing oil well XX-1 in the GX operating area of ​​a certain oil field by adopting the deep gravel filling sand control method of the drillable sand control screen. After 18 months, salvage operations are required. The drillable sand control screen lowered into the sand-producing oil well is drilled, ground and salvaged using a Ф89mm drill rod + a Ф100mm drill bit. After 5 days of operation, the drillable sand control screen is completely salvaged.

[0033] Embodiment 2:

[0034] The drillable sand control screen provided in this embodiment is a glass fiber reinforced plastic composite material pipe with vertical screen slots, which is made of epoxy resin as a matrix, glass fiber as a reinforcing material, and an improver; the mass ratio of the epoxy resin, glass fiber and improver is 36:59:7. The improver is composed of a diluent, a leveling agent and an anti-settling agent, wherein the diluent is compounded with butyl acetate and cyclohexanone in a ratio of 1:1; the leveling agent adopts modified acrylate, and the amount thereof accounts for 0.5% of the total amount of the improver; the anti-settling agent adopts polyolefin, and the amount thereof accounts for 0.5% of the total amount of the improver.

[0035] The preparation method is as follows: pre-treat the surface of the glass fiber including degreasing, then immerse it in a mixture of epoxy resin and improver, and then evenly wind it on the outer surface of the core mold in a spiral manner. The winding angle of the glass fiber is 45°. When the thickness reaches 9.5mm, solidify and demould to obtain a drillable sand screen base pipe; then use a sheet milling cutter to mill a plurality of vertical screen slots set at intervals on the circumferential wall of the drillable sand screen base pipe, thereby making a drillable sand screen. The drillable sand screen has a length of 4.5m, an outer diameter of 95mm, and an inner diameter of 76mm; the width of the vertical screen slot is 0.3mm, the length is 56mm, and the density is 250 per meter.

[0036] like Figure 2 As shown, the deep gravel packing sand control method using the drillable sand control screen comprises the following steps performed in sequence:

[0037] 1) On the ground, the staff uses a band clamp to connect the drillable sand control screen pipes together in an end-to-end manner to form a sand control pipe column 3; then install the sand control hand-release tool 2 and the wire plug 4 at the upper and lower ends of the sand control pipe column 3 respectively;

[0038] 2) Slowly lower the sand control pipe string 3 together with the sand control hand-release tool 2 and the wire plug 4 into the casing 5 in the sand-producing oil well at a lowering speed of 0.4 m / min to prevent the sand control pipe string 3 from colliding with the casing 5 due to excessive lowering speed, thereby causing breakage, until the middle position of the sand control pipe string 3 is aligned with the oil layer 6, and the upper end of the sand control pipe string 3 is 3 meters higher than the top of the oil layer 6, and the lower end is 3.5 meters lower than the bottom of the oil layer 6;

[0039] 3) Use a pump truck to pump sand-carrying fluid into the oil pipe 1 for gravel packing. During this process, the pump pressure should be paid attention to in real time. By adjusting the pump truck displacement and the filling sand ratio, the gravel is filled in the near-wellbore area and the screen annulus to form a near-wellbore area filling zone A and a screen annulus filling zone B. In this embodiment, the pump truck displacement is required to be 1.8m 3 / min or less, the filling sand ratio is set to 6%. If the pump pressure remains stable for a period of time, the sand ratio is increased step by step, and 4-6m3 of sand is added in each stage. 3 , the total amount of sand added is 30m 3 and ensure that the top surface of the screen annulus filling zone B is located 30 meters above the upper end of the sand control tool; then pump in clean water to push the sand-carrying liquid out of the oil pipe 1; thus completing the gravel filling process;

[0040] 4) If the sand control pipe column 3 needs to be salvaged in the later stage of oil production, a drill pipe connected with a drill bit is lowered into the casing 5, and the drill bit is used to drill and grind the sand control pipe column 3 lowered into the sand-producing oil well, and the screen pipe debris after drilling will be salvaged with the well repair protection fluid.

[0041] The drillable sand control screen provided by the embodiment of the present invention is used to carry out sand control operations on the XX-2 sand-producing oil well in the GX operating area of ​​a certain oil field by adopting the deep gravel filling sand control method of the drillable sand control screen. After 20 months, salvage operations are required. The drillable sand control screen lowered into the sand-producing oil well is drilled, ground and salvaged using a Ф89mm drill rod + a Ф100mm drill bit. After 7 days of operation, the drillable sand control screen is completely salvaged.

Claims

1. A drillable sand control screen, characterized in that: The drillable sand control screen pipe is a glass fiber reinforced plastic composite material pipe with vertical screen slots, which is made of epoxy resin as a matrix, glass fiber as a reinforcing material, and an improving agent. The preparation method is as follows: pre-treating the surface of the glass fiber including degreasing, then immersing it in a mixture of epoxy resin and improver, then spirally winding it evenly on the outer surface of the core mold, and finally curing and demolding it to obtain a drillable sand control screen pipe base pipe; then using a sheet milling cutter to mill a plurality of vertical screen slots set at intervals on the circumferential wall of the drillable sand control screen pipe base pipe, thereby making the drillable sand control screen pipe.

2. The drillable sand control screen according to claim 1, characterized in that: The mass ratio of the epoxy resin, the glass fiber and the improver is: 30-40: 50-60: 5-10.

3. The drillable sand control screen according to claim 1, characterized in that: The improver consists of a diluent, a leveling agent and an anti-settling agent, wherein the diluent is prepared by compounding butyl acetate and cyclohexanone in a ratio of 1:1; the leveling agent is modified acrylate, and its usage accounts for 0.1-1% of the total improver; the anti-settling agent is polyolefin, and its usage accounts for 0.1-1% of the total improver.

4. The drillable sand control screen according to claim 1, characterized in that: The winding angle of the glass fiber is 45°.

5. The drillable sand control screen according to claim 1, characterized in that: The vertical sieve slits have a width of 0.2-0.4 mm, a length of 50-60 mm, and a density of 150-250 slits / m.

6. A deep gravel packing sand control method using the drillable sand control screen according to any one of claims 1 to 5, characterized in that: The method comprises the following steps performed in sequence: 1) On the ground, a worker uses a band clamp to connect the drillable sand control screen pipes end to end to form a sand control pipe column (3); then install a sand control hand-release tool (2) and a thread plug (4) at the upper and lower ends of the sand control pipe column (3); 2) Slowly lower the sand control pipe column (3) together with the sand control hand-release tool (2) and the wire plug (4) into the casing (5) in the sand-producing oil well until the middle position of the sand control pipe column (3) is aligned with the oil layer (6), and the upper end of the sand control pipe column (3) is more than 3 meters higher than the top of the oil layer (6), and the lower end is more than 3 meters lower than the bottom of the oil layer (6); 3) Use a pump truck to pump sand-carrying fluid into the oil pipe (1) for gravel packing. During this process, the pump pressure should be paid attention to in real time. By adjusting the displacement of the pump truck and the filling sand ratio, the gravel is filled in the near-wellbore area and the screen annulus to form a near-wellbore area filling zone (A) and a screen annulus filling zone (B), and ensure that the top surface of the screen annulus filling zone (B) is located 30 meters above the upper end of the sand prevention tool (2); then pump clean water to push the sand-carrying fluid out of the oil pipe (1); thereby completing the gravel packing process; 4) If the sand control pipe column (3) needs to be salvaged in the later stage of oil production, a drill rod connected with a drill bit is lowered into the casing (5), and the sand control pipe column (3) lowered into the sand producing oil well is drilled and ground by the drill bit, and the screen pipe debris after drilling will be salvaged with the well repair protection fluid.

7. The deep gravel packing sand control method of the drillable sand control screen according to claim 6, characterized in that: In step 2), the downward movement speed of the sand control pipe column (3) is less than 0.5 m / min.

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