Segmented sand proppant flow conductivity test device and method

Abstract

The present application relates to the technical fields of proppant conductivity test experiment, and is a sectional sand proppant conductivity test device and test method, which comprises a conductivity chamber, a liquid inlet on the left side wall of the conductivity chamber and communicated with a proppant laying space, a liquid outlet on the right side wall of the conductivity chamber and communicated with the proppant laying space, an upper metal cover plate, a flexible rubber plate and a metal split layer stacked together from top to bottom on the upper side of the proppant laying space, a lower metal cover plate on the lower side of the proppant laying space, and three pressure measuring holes evenly and spacedly distributed on the front side wall of the conductivity chamber corresponding to the position of the proppant laying space. The present application has a reasonable structure, and can realize the purpose of sectional laying of different types of proppants with a certain volume ratio through the setting of four single section areas. The purpose of testing the conductivity values of each section of proppants when different types of proppants are combined and sectionally laid can be realized through the control of the opening and closing of the five pressure measuring holes.

Description

Technical Field

[0001] This invention relates to the field of experimental technology for testing the flowability of proppant, and is a test device and method for testing the flowability of segmented sand-laying proppant. Background Technology

[0002] With the continuous utilization and development of low-permeability, ultra-low-permeability, and other unconventional reservoirs, hydraulic fracturing plays an increasingly important role as a crucial technology for the efficient stimulation of such reservoirs. In hydraulic fracturing, forming propped fractures with sufficient permeability is a key indicator for achieving efficient stimulation. The fracture conductivity is a critical parameter used in fracturing operation design and effect prediction. Large-scale proppant fracturing operations are frequently employed in the stimulation of low-permeability, ultra-low-permeability, and tight oil and gas reservoirs, with proppant additions often reaching thousands of tons. To reduce costs and increase efficiency, the combination of high-performance, high-cost ceramsite with medium-to-low-performance, lower-cost quartz sand has become common. When different types of proppant are combined, their conductivity changes compared to a single proppant, making calculations based on the conductivity of a single proppant impossible. Therefore, it is necessary to conduct conductivity experiments with different proppant combinations in segmented placement to explore the influence of proppant combinations on conductivity, ultimately providing important basic parameters and guidance for predicting the conductivity of hydraulically fractured propped fractures and fracturing effects. Therefore, indoor experimental studies on the effect of segmented placement of different types of proppant on the flow conductivity of propped cracks are of great significance. Summary of the Invention

[0003] This invention provides a segmented sand-laying proppant flow testing device and method, which overcomes the shortcomings of the prior art. It can effectively solve the problem that existing proppant flow testing devices cannot test the flow capacity of each segment of proppant when different types of proppant combinations are used in segmented sand laying.

[0004] One of the technical solutions of this invention is achieved through the following measures: a segmented sand-laying proppant flow guiding test device, comprising a flow guiding chamber, in which a cuboid proppant laying space is formed; an inlet communicating with the proppant laying space is provided on the left side wall of the flow guiding chamber; an outlet communicating with the proppant laying space is provided on the right side wall of the flow guiding chamber; an upper metal cover plate, a flexible rubber plate, and a metal split layer are stacked sequentially from top to bottom on the upper side of the proppant laying space; a lower metal cover plate is provided on the lower side of the proppant laying space, corresponding to the proppant... Three pressure measuring holes are evenly spaced from left to right on the front wall of the proppant placement chamber. These three holes, each corresponding to a vertical plane passing through their central axes, divide the proppant placement space into four equal-volume single-segment regions arranged from left to right. The metal split layer includes four metal plates corresponding to the four single-segment regions. An upper piston is located above the upper metal cover plate, and a lower piston is located below the lower metal cover plate. The proppant placement space is also located on the left side wall of the proppant chamber corresponding to the inlet position and the right side wall of the proppant chamber corresponding to the outlet position. Each of the five pressure measuring ports is defined as follows: from left to right, they are: first pressure measuring port, second pressure measuring port, third pressure measuring port, fourth pressure measuring port, and fifth pressure measuring port. The first and second pressure measuring ports are connected through a first pressure measuring pipe. A first differential pressure sensor is installed on the first pressure measuring pipe. A first three-way valve is installed on the first pressure measuring pipe at the position between the first differential pressure sensor and the second pressure measuring port. The remaining port of the first three-way valve is connected to the third pressure measuring port through a second pressure measuring pipe. A second differential pressure sensor is installed on the second pressure measuring pipe. A second three-way valve is installed on the second pressure measuring pipe at the position between the second differential pressure sensor and the third pressure measuring port. The remaining port of the second three-way valve is connected to the fourth pressure measuring port through a third pressure measuring pipe. A third differential pressure sensor is installed on the third pressure measuring pipe. A third three-way valve is installed on the third pressure measuring pipe at the position between the third differential pressure sensor and the fourth pressure measuring port. The remaining port of the third three-way valve is connected to the fifth pressure measuring port through a fourth pressure measuring pipe. A fourth differential pressure sensor is installed on the fourth pressure measuring pipe.

[0005] The following are further optimizations and / or improvements to one of the above-mentioned inventive solutions:

[0006] The aforementioned segmented sand proppant flow testing device may also include a horizontal flow pump, a vacuum pump, a back pressure controller, and a measuring cylinder. The outlet and inlet of the horizontal flow pump are connected by an inlet pipe, and the outlet is connected to the measuring cylinder through a first outlet pipe. A back pressure controller is installed on the first outlet pipe. A second outlet pipe is connected to the first outlet pipe at the position between the outlet and the back pressure controller through a three-way control valve. A vacuum pump is installed at the outlet of the second outlet pipe. Control valves are provided on the inlet pipe, the second outlet pipe, and the first inlet pipe at the position between the three-way control valve and the back pressure controller.

[0007] A filter screen can be installed at the liquid inlet, liquid outlet, and each pressure measuring hole.

[0008] The thickness of the aforementioned flexible rubber sheet can be from 1 mm to 3 mm.

[0009] The second technical solution of the present invention is achieved through the following measures: the testing method of the segmented sand proppant flow guiding test device includes the following steps:

[0010] S1: Select various different types of proppant according to the experimental design;

[0011] S2: Multiple different types of proppant are laid in segments with a certain volume ratio in the proppant laying space to form a proppant filling layer. The top of the proppant filling layer is scraped flat, and then an initial pressure of 10kN is applied to the upper and lower pistons in the flow chamber through a pressure testing machine.

[0012] S3: Adjust the back pressure controller to set the back pressure value. The back pressure value is the pore pressure that the proppant bears under formation conditions.

[0013] S4: Pump liquid into the flow chamber using a horizontal flow pump. The liquid is distilled water or a 2wt% KCl aqueous solution. Test the flow conductivity of the proppant-filled layer and calculate its permeability and flow conductivity values.

[0014] The following are further optimizations and / or improvements to the second invention solution described above:

[0015] In step S1 above, two different types of proppant can be selected, one of which is ceramsite proppant and the other is quartz sand proppant, with a volume ratio of 1:1 between the two proppants.

[0016] The different types of proppant selected in step S1 above can be three: 70 / 140 mesh quartz sand proppant, 40 / 70 mesh ceramsite proppant, and 30 / 50 mesh quartz sand proppant, with a volume ratio of 1:1:1.

[0017] This invention has a reasonable structure. By setting up four single-segment areas, it can achieve the purpose of laying various types of proppant in segments with a certain volume ratio. By controlling the opening and closing of five pressure testing holes, it can test the flow conductivity of each segment of proppant when laying sand in segments with different types of proppant combinations, which is of great significance for on-site construction. By setting up a flexible rubber plate, it can solve the problem of uneven stress when laying different types of proppant in segments, and improve the accuracy of the tested flow conductivity values ​​of each segment of proppant. By setting up a metal split layer, it can effectively avoid the problem of proppant embedding into the flexible rubber plate. Attached Figure Description

[0018] Appendix Figure 1 These are schematic diagrams of the structures of Embodiment 1 and Embodiment 2 of the present invention.

[0019] Appendix Figure 2 This is a schematic diagram of a partial cross-sectional view of the main structure when two different types of proppant are laid in the diversion chamber in Embodiment 1 and Embodiment 2 of the present invention.

[0020] Appendix Figure 3 This is a partial sectional view of the main structure of the diversion chamber in Embodiments 1 and 2 of the present invention, where three different types of proppant are laid.

[0021] The codes in the attached diagram are as follows: 1 is the flow guide chamber, 2 is the upper metal cover plate, 3 is the flexible rubber plate, 4 is the lower metal cover plate, 5 is the single-segment area, 6 is the metal plate, 7 is the upper piston, 8 is the lower piston, 9 is the first pressure measuring pipe, 10 is the second pressure measuring pipe, 11 is the third pressure measuring pipe, 12 is the fourth pressure measuring pipe, 13 is the first differential pressure sensor, 14 is the second differential pressure sensor, 15 is the third differential pressure sensor, 16 is the fourth differential pressure sensor, 17 is the first three-way valve, 18 is the second three-way valve, 19 is the third three-way valve, 20 is the horizontal flow pump, 21 is the vacuum pump, 22 is the back pressure controller, 23 is the measuring cylinder, 24 is the first liquid outlet pipe, 25 is the three-way control valve, 26 is the second liquid outlet pipe, 27 is the control valve, 28 is the first pressure measuring port, 29 is the second pressure measuring port, 30 is the third pressure measuring port, 31 is the fourth pressure measuring port, and 32 is the fifth pressure measuring port. Detailed Implementation

[0022] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0023] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 2 The layout is described using a diagrammatic method, such as front, back, top, bottom, left, right, etc. The positional relationships are determined based on the layout direction of the attached diagram in the instruction manual.

[0024] The present invention will be further described below with reference to embodiments and accompanying drawings:

[0025] Example 1: As shown in the attached document Figure 1-3As shown, the segmented sand-laying proppant diversion test device and test method includes a diversion chamber 1, within which a cuboid proppant laying space is formed. An inlet communicating with the proppant laying space is located on the left side wall of the diversion chamber 1, and an outlet communicating with the proppant laying space is located on the right side wall of the diversion chamber 1. Above the proppant laying space, an upper metal cover plate 2, a flexible rubber plate 3, and a metal split layer are stacked sequentially from top to bottom. Below the proppant laying space, a lower metal cover plate 4 is located. On the front side wall of the diversion chamber 1 corresponding to the proppant laying space, proppant layers are evenly distributed from left to right. Three pressure measuring holes, each corresponding to a vertical plane passing through the central axis of the three pressure measuring holes, divide the proppant placement space into four equal-volume single-segment regions 5 arranged from left to right. The metal split layer includes four metal plates 6 corresponding to the four single-segment regions 5. An upper piston 7 is provided above the upper metal cover plate 2, and a lower piston 8 is provided below the lower metal cover plate 4. A pressure measuring hole is provided on the left side wall of the guide chamber 1 corresponding to the liquid inlet position and on the right side wall of the guide chamber 1 corresponding to the liquid outlet position. The five pressure measuring holes are defined as the first pressure measuring hole 28 from left to right. The second pressure measuring port 29, the third pressure measuring port 30, the fourth pressure measuring port 31, and the fifth pressure measuring port 32 are connected by the first pressure measuring port 28 and the second pressure measuring port 29 via a first pressure measuring pipe 9. A first differential pressure sensor 13 is installed on the first pressure measuring pipe 9. A first three-way valve 17 is installed on the first pressure measuring pipe 9 at the position between the first differential pressure sensor 13 and the second pressure measuring port 29. The remaining port of the first three-way valve 17 is connected to the third pressure measuring port 30 via the second pressure measuring pipe 10. A second differential pressure sensor 14 is installed on the second pressure measuring pipe 10. A second three-way valve 18 is installed on the second pressure measuring pipe 10 located between the third pressure measuring port 30 and the third pressure measuring port 30. The remaining port of the second three-way valve 18 is connected to the fourth pressure measuring port 31 through the third pressure measuring pipe 11. A third differential pressure sensor 15 is installed on the third pressure measuring pipe 11 located between the third differential pressure sensor 15 and the fourth pressure measuring port 31. A third three-way valve 19 is installed on the third pressure measuring pipe 11 located between the third differential pressure sensor 15 and the fourth pressure measuring port 31. The remaining port of the third three-way valve 19 is connected to the fifth pressure measuring port 32 through the fourth pressure measuring pipe 12. A fourth differential pressure sensor 16 is installed on the fourth pressure measuring pipe 12.

[0026] This application divides the proppant placement space into four equal-volume, sequentially arranged single-segment regions 5, thereby enabling the segmented placement of two to four different types of proppant in a specific volume ratio. For example, when two different types of proppant are combined for segmented placement, the two types of proppant can be laid in segments within the proppant placement space at a volume ratio of 1:1, 1:2, or 1:3. Specifically, when the two types of proppant are laid in segments at a 1:1 volume ratio, the two single-segment regions 5 on the left are used to lay one type of proppant, and the two single-segment regions 5 on the right are used to lay the other type of proppant. When the two types of proppant are laid in segments at a 1:2 volume ratio, the leftmost single-segment region 5 is used to lay one type of proppant, the two middle single-segment regions 5 are used to lay the other type of proppant, and the rightmost single-segment region 5 is left empty. When the two types of proppant are laid in segments at a 1:3 volume ratio, as shown in the attached... Figure 2 As shown, the leftmost single-segment area 5 is used to lay one type of proppant, and the three single-segment areas 5 on the right are used to lay another type of proppant. When three different types of proppant are combined and laid in segments, the two types of proppant can be laid in segments with a volume ratio of 1:1:1 or 1:2:1 within the proppant laying space. Specifically, when the three types of proppant are laid in segments with a volume ratio of 1:1:1, as shown in the attached diagram... Figure 3 As shown, the three single-segment areas 5 on the left are each used to lay one type of proppant individually, while the rightmost single-segment area 5 is empty. When the three types of proppant are laid in a 1:2:1 volume ratio, the leftmost single-segment area 5 is used to lay one type of proppant, the two middle single-segment areas 5 are used to lay one type of proppant, and the rightmost single-segment area 5 is used to lay another type of proppant. When four different types of proppant are combined and laid in segments, two types of proppant can be laid in segments in a 1:1:1:1 volume ratio within the proppant laying space, meaning each single-segment area 5 is used to lay one type of proppant individually. Furthermore, this application can, based on the specific situation of different types of proppant being laid in segments according to a certain volume ratio, control the opening and closing of the corresponding pressure testing holes to achieve...

[0027] The flow conductivity of each proppant segment was tested when different types of proppant combinations were used for segmented sand laying.

[0028] Furthermore, since different types of proppant are non-uniform and discontinuous materials, their mechanical parameters vary at different points. Under external load, the forces between blocks or particles in some areas are large, while other areas experience very little or no force. Therefore, if a rigid boundary loading testing machine is used to conduct mechanical tests on crushed stone materials, the non-uniformity of force will be reflected at the boundary, leading to uneven and uncertain force distribution at the boundary. This affects the accuracy of studying the effect of segmented placement of different types of proppant on the propping crack conductivity. If the upper metal cover plate 2 and lower metal cover plate 4 in the existing propping conductivity testing device are used to apply closing stress to the propping filling layer formed by segmented placement of different types of proppant, the loading method is rigid. This loading method will lead to uneven force distribution between different types of proppant. A certain type of proppant with higher strength will have already compressed and deformed into place under a smaller closing stress, forming a support platform, causing the upper metal cover plate 2 to... The lower metal cover plate 4 is mainly supported by this, while a certain type of proppant with lower strength is difficult to compress and deform as required. In this application, a flexible rubber plate 3 and a metal split layer are set below the upper metal cover plate 2. The flexible rubber plate 3 has the characteristics of low hardness (softness), easy deformation (superelasticity), and ability to withstand high pressure. At the same time, the Poisson's ratio of the rubber material is close to 0.5, and its volume is almost incompressible. The super-flexible rubber can be like a liquid loading capsule, which can uniformly transfer the closing stress to the surface of the proppant filling layer and deform with the deformation of the surface of the proppant filling layer, thereby achieving flexible and uniform pressure loading. The metal split layer is set below the flexible rubber plate 3, which can effectively avoid the problem of proppant embedding into the flexible rubber plate 3. Flexible uniform pressure loading is significantly more effective than rigid loading. For proppant with uneven surfaces, the flexible rubber sheet 3 can better transmit uniform pressure. The uniformity of the stress field in the proppant laying area increases with the decrease of the Shore hardness of the flexible rubber sheet 3 and the increase of the loading pressure and the depth from the surface. The flexible rubber sheet 3 can realistically simulate stress boundary conditions, which is beneficial to improving the accuracy of the proppant crack conductivity value when testing different types of proppant segmented laying.

[0029] The above embodiment one can be further optimized and / or improved according to actual needs:

[0030] As attached Figure 1As shown, the system also includes a horizontal flow pump 20, a vacuum pump 21, a back pressure controller 22, and a measuring cylinder 23. The outlet and inlet of the horizontal flow pump 20 are connected by an inlet pipe, and the outlet is connected to the measuring cylinder 23 through a first outlet pipe 24. A back pressure controller 22 is installed on the first outlet pipe 24. A second outlet pipe 26 is connected to the first outlet pipe 24 at the position between the outlet and the back pressure controller 22 through a three-way control valve 2725. The vacuum pump 21 is installed at the outlet of the second outlet pipe 26. Control valves 27 are provided on the inlet pipe, the second outlet pipe 26, and the first inlet pipe at the position between the three-way control valve 2725 and the back pressure controller 22. Thus, liquid is pumped into the flow chamber 1 by the horizontal flow pump 20, and the back pressure value is set by the back pressure controller 22. The back pressure value is the pore pressure that the proppant withstands in the formation state. The vacuum pump 21 can evacuate the flow chamber 1.

[0031] Specifically, filters are installed at the inlet, outlet, and each pressure test hole. This is to prevent the crushed proppant from flowing out.

[0032] Specifically, the thickness of the flexible rubber sheet 3 is 1mm to 3mm. The thickness of the flexible rubber sheet 3 can be adjusted according to specific needs; in this embodiment, the thickness of the flexible rubber sheet 3 is 1mm.

[0033] Example 2: The testing method for this segmented sand proppant flow guiding test device includes the following steps:

[0034] S1: Select various different types of proppant according to the experimental design;

[0035] S2: Multiple different types of proppant are laid in segments with a certain volume ratio in the proppant laying space to form a proppant filling layer. The top of the proppant filling layer is scraped flat, and then an initial pressure of 10kN is applied to the upper piston 7 and lower piston 8 in the flow chamber 1 by a pressure testing machine.

[0036] S3: Adjust the back pressure controller 22 to set the back pressure value. The back pressure value is the pore pressure that the proppant bears under formation conditions.

[0037] S4: Liquid, which is distilled water or 2wt% KCl aqueous solution, is pumped into the flow chamber 1 through the horizontal flow pump 20 to test the flow conductivity of the proppant filling layer and calculate its permeability and flow conductivity values.

[0038] Specifically, the different types of proppant in step S1 include proppants with different compositions, as well as proppants with the same composition but different particle sizes. That is, if two proppants have different compositions, they are considered two different types of proppants as described in this application. If two proppants have the same composition but different particle sizes, such as 70 / 140 mesh quartz sand and 30 / 50 mesh quartz sand, they are also considered two different types of proppants as described in this application. In step S4 above, the vacuum pump 21 can be turned on to evacuate the air first. After 30 minutes, the liquid can be pumped into the flow chamber 1 by the horizontal flow pump 20, and the evacuation can continue until the evacuation is completed.

[0039] This application allows for the testing of the conductivity of each proppant segment by controlling the opening and closing of corresponding pressure testing holes, based on the specific situation of segmented sand laying with different types of proppant at a certain volume ratio. For example, when testing the conductivity of each proppant segment when quartz sand and ceramsite are laid in a 1:3 volume ratio, the two types of proppant are laid in sections according to the attached... Figure 2 The proppant is laid in the following manner: quartz sand proppant is laid in the leftmost single-segment area 5, and ceramsite proppant is laid in the three single-segment areas 5 on the right. The first, second, and fifth pressure measuring holes 32 are kept open, while the third and fourth pressure measuring holes 31 are closed. Then, pressure is applied to the upper piston 7 and lower piston 8 in the flow chamber 1 using a pressure testing machine. Liquid, which is a 2wt% KCl aqueous solution, is pumped into the flow chamber 1 through a horizontal flow pump 20. Then, the conductivity value of each proppant segment is calculated according to the formula in the industry standard SY / T6302-2009 "Evaluation Method for Short-Term Conductivity of Fracturing Proppant Filling Layer". The formula is as follows:

[0040] kW f1 =μQL1 / (99.998wΔp1) (1)

[0041] kW f2 =μQL2 / (99.998wΔp2) (2)

[0042] In the above formulas (1) and (2), KW f1 To improve the fracture conductivity of the quartz sand-filled layer, KW f2 The conductivity of the cracks in the ceramsite-filled layer is expressed in square micrometers per centimeter (μm). 2 K is the permeability of the proppant-filled layer, in square micrometers (μm). 2 );W f1 W f2 , respectively, represent the thickness of the quartz sand and ceramsite filling layers, in centimeters (cm); μ is the viscosity of the test liquid at the test temperature, in millipascal-seconds (mPa·s); Q is the liquid flow rate, in cubic centimeters per minute (cm³). 3 / min); L1 is the distance between the first pressure measuring hole 28 and the second pressure measuring hole 29, and L2 is the distance between the second pressure measuring hole 29 and the fifth pressure measuring hole 32, in centimeters (cm); w is the width of the flow guide chamber 1, in centimeters (cm); ΔP1 is the pressure drop between the first pressure measuring hole 28 and the second pressure measuring hole 29, and ΔP2 is the pressure drop between the second pressure measuring hole 29 and the fifth pressure measuring hole 32, in kilopascals (kPa).

[0043] When testing the flow conductivity of proppant in segments of 70 / 140 mesh quartz sand, 40 / 70 mesh ceramsite, and 30 / 50 mesh quartz sand at a volume ratio of 1:1:1, the three types of proppant are arranged as follows: Figure 3 The proppant is laid in the following manner: the three types of proppant are laid sequentially from left to right in the three single-segment regions 5 on the left, with the rightmost single-segment region 5 left empty. The fifth pressure measuring hole 32 is closed, and the first, second, third, and fourth pressure measuring holes 31 are opened. At this time, the conductivity value of each proppant segment can be calculated by the following formula:

[0044] kW f3 =μQL / (99.998wΔp3) (3)

[0045] kW f4 =μQL / (99.998wΔp4) (4)

[0046] kW f5 =μQL / (99.998wΔp5) (5)

[0047] In the above formulas (3), (4), and (5), KW f3 For the crack conductivity of the 70 / 140 mesh quartz sand filling layer, KW f4 For the crack conductivity of the 40 / 70 mesh ceramsite filling layer, KW f5 The crack conductivity of a 30 / 50 mesh quartz sand-filled layer is expressed in square micrometers per centimeter (μm). 2 K is the permeability of the proppant-filled layer, in square micrometers (μm). 2 );W f3 W f4 W f5 The thicknesses of the filling layers are 70 / 140 mesh quartz sand, 40 / 70 mesh ceramsite, and 30 / 50 mesh quartz sand, respectively, in centimeters (cm); μ is the viscosity of the test liquid at the test temperature, in millipascal-seconds (mPa·s); Q is the liquid flow rate, in cubic centimeters per minute (cm³). 3 / min); L is the distance between two adjacent pressure measuring holes, in centimeters (cm); w is the width of the flow guide chamber 1, in centimeters (cm); ΔP3 is the pressure drop between the first pressure measuring hole 28 and the second pressure measuring hole 29, ΔP4 is the pressure drop between the second pressure measuring hole 29 and the third pressure measuring hole 30, and ΔP5 is the pressure drop between the third pressure measuring hole 30 and the fourth pressure measuring hole 31, in kilopascals (kPa).

[0048] The above technical features constitute the preferred embodiment of the present invention, which has strong adaptability and optimal implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the requirements of different situations.

Claims

1. A segmented sand-laying proppant flow guiding test device, characterized in that... The system includes a flow guide chamber, within which a rectangular proppant placement space is formed. An inlet communicating with the proppant placement space is located on the left side wall of the flow guide chamber, and an outlet communicating with the proppant placement space is located on the right side wall. Above the proppant placement space, an upper metal cover plate, a flexible rubber plate, and a metal split layer are stacked sequentially from top to bottom. Below the proppant placement space, a lower metal cover plate is located. Three pressure measuring holes are evenly distributed from left to right on the front wall of the flow guide chamber corresponding to the proppant placement space. A vertical plane passing through the central axis of these three pressure measuring holes divides the proppant placement space into four equal-volume single-segment regions arranged sequentially from left to right. The metal split layer includes four metal plates corresponding to the four single-segment regions. An upper piston is located above the upper metal cover plate, and a lower piston is located below the lower metal cover plate. A pressure measuring hole is located on the left side wall of the flow guide chamber corresponding to the inlet position and on the right side wall of the flow guide chamber corresponding to the outlet position, defining five pressure measuring holes. From left to right, the components are: first pressure measuring hole, second pressure measuring hole, third pressure measuring hole, fourth pressure measuring hole, and fifth pressure measuring hole. The first and second pressure measuring holes are connected through a first pressure measuring pipe. A first differential pressure sensor is installed on the first pressure measuring pipe. A first three-way valve is installed on the first pressure measuring pipe at the position between the first differential pressure sensor and the second pressure measuring hole. The remaining port of the first three-way valve is connected to the third pressure measuring hole through the second pressure measuring pipe. A second differential pressure sensor is installed on the second pressure measuring pipe. A second three-way valve is installed on the second pressure measuring pipe at the position between the second differential pressure sensor and the third pressure measuring hole. The remaining port of the second three-way valve is connected to the fourth pressure measuring hole through the third pressure measuring pipe. A third differential pressure sensor is installed on the third pressure measuring pipe. A third three-way valve is installed on the third pressure measuring pipe at the position between the third differential pressure sensor and the fourth pressure measuring hole. The remaining port of the third three-way valve is connected to the fifth pressure measuring hole through the fourth pressure measuring pipe. A fourth differential pressure sensor is installed on the fourth pressure measuring pipe.

2. The segmented sand-laying proppant flow guiding test device according to claim 1, characterized in that... It also includes a horizontal flow pump, a vacuum pump, a back pressure controller, and a measuring cylinder. The outlet and inlet of the horizontal flow pump are connected by an inlet pipe, and the outlet is connected to the measuring cylinder through a first outlet pipe. A back pressure controller is installed on the first outlet pipe. A second outlet pipe is connected to the first outlet pipe at the position between the outlet and the back pressure controller through a three-way control valve. A vacuum pump is installed at the outlet of the second outlet pipe. Control valves are provided on the inlet pipe, the second outlet pipe, and the first inlet pipe at the position between the three-way control valve and the back pressure controller.

3. The segmented sand-laying proppant flow guiding test device according to claim 1 or 2, characterized in that... A filter screen is installed at the inlet, outlet, and each pressure test hole.

4. The segmented sand-laying proppant flow guiding test device according to claim 1 or 2, characterized in that... The thickness of the flexible rubber sheet ranges from 1mm to 3mm.

5. A test method for the segmented sand-laying proppant flow guiding test device as described in claim 2, characterized in that... Includes the following steps: S1: Select various different types of proppant according to the experimental design; S2: Multiple different types of proppant are laid in segments with a certain volume ratio in the proppant laying space to form a proppant filling layer. The top of the proppant filling layer is scraped flat, and then an initial pressure of 10kN is applied to the upper and lower pistons in the flow chamber through a pressure testing machine. S3: Adjust the back pressure controller to set the back pressure value. The back pressure value is the pore pressure that the proppant bears under formation conditions. S4: Pump liquid into the flow chamber using a horizontal flow pump. The liquid is distilled water or a 2wt% KCl aqueous solution. Test the flow conductivity of the proppant-filled layer and calculate its permeability and flow conductivity values.

6. The test method of the segmented sand proppant flow guiding test device according to claim 5, characterized in that... Two different types of proppant are selected in step S1: one is ceramsite proppant and the other is quartz sand proppant, with a volume ratio of 1:

1.

7. The test method of the segmented sand proppant flow guiding test device according to claim 5, characterized in that... Three different types of proppant are selected in step S1: 70 / 140 mesh quartz sand proppant, 40 / 70 mesh ceramsite proppant, and 30 / 50 mesh quartz sand proppant. The volume ratio of the three proppants is 1:1:1.

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