Method for rapid testing of the free fall height of slurry in a filling standpipe

Abstract

The application provides a method for quickly testing the free falling section height of slurry in a filling vertical pipe, a plurality of sensors are arranged at specific positions of the filling pipe, a test ball with a signal transmitter arranged inside and the same density as the slurry is made to freely fall from a discharge port along with the slurry, the time when the test ball passes through each sensor is recorded, and finally the free falling section height of the slurry in the filling vertical pipe is calculated according to the test result and known conditions. The test ball with the same density as the slurry is made to move into the filling vertical pipe at the same time as the slurry, the arrangement positions of the sensors are matched, and the free falling section height of the slurry in the filling vertical pipe is accurately and ingeniously calculated by using the test result, the position of the section of the vertical pipe which is easy to be damaged during filling in different areas is found out, data support for optimizing the pipe network design is provided, the operation and running safety of the filling vertical pipe is ensured, the service life of the filling vertical pipe is prolonged, and the application can be popularized and applied on a large scale in the fields of wear detection of mine filling vertical pipes and optimal design of filling pipe networks.

Description

Technical Field

[0001] This invention relates to the field of mine backfilling technology, and in particular to a method for rapidly testing the height of the free fall section of slurry in a backfilling vertical pipe. Background Technology

[0002] The filling riser is the crucial link between the surface preparation station and the underground void. The cost of a single riser is usually several million yuan. Once the riser is partially worn through or damaged, it is difficult to repair. The usual practice is to re-drill and install the riser nearby, which is not only very costly, but also affects the normal production and operation of the mining company, disrupts the balance between mining and filling, and leaves safety hazards.

[0003] After the filling slurry enters the riser, it first undergoes a free fall for a certain distance. Then, it forms a full-pipe flow within a specific area, transporting the slurry from the riser, elbows, and horizontal pipes to the empty area to complete the filling. The main reason for the rapid wear of the filling riser is the enormous kinetic energy converted from the potential energy of the free-falling slurry. This energy is released at the gas-liquid interface, accompanied by the formation of a vacuum, which impacts the inner wall of the pipe in a small area. As the filling time increases, when the filling volume reaches hundreds of thousands of cubic meters (or the filling time reaches thousands of hours), the inner wall of the riser pipe will be damaged under the frequent impacts of high energy density and heavy loads.

[0004] To address the damage to the riser pipe wall caused by the free fall of slurry and extend its service life, it is necessary to optimize the downhole filling network to minimize the height of the free fall section, ultimately aiming for full flow throughout the riser. However, in actual production, it is essential to continuously measure the position of the gas-liquid interface during free fall to provide a basis for optimized design and to continuously monitor the effects of network optimization. This requires a rapid, efficient, and low-cost device and method for testing the height of the free fall section of the filling riser slurry.

[0005] Currently, the main method for determining the height of the free-fall section of the filling slurry in a vertical pipe is borehole camera technology. This involves suspending a camera and recording video of pipe wall wear to determine the location of the gas-liquid interface. This method has the following drawbacks:

[0006] (1) The testing time is long, requiring 2 to 3 days to test a single vertical pipe, and all filling operations must be stopped, affecting on-site production;

[0007] (2) The testing costs are high, ranging from tens of thousands to hundreds of thousands of yuan for imaging and data analysis of the inner wall of a single vertical pipe;

[0008] (3) The test is delayed and can only test cases that have already caused obvious impact and damage. It cannot play a role in early prevention or early planning.

[0009] In view of this, it is necessary to design an improved method for rapidly testing the height of the free fall section of the slurry in the filling riser to solve the above problems. Summary of the Invention

[0010] The purpose of this invention is to provide a method for rapidly testing the height of the free fall section of slurry in a filling riser. A test ball of the same density enters the filling riser simultaneously with the slurry. By coordinating the placement of sensors, the test results are used to accurately and ingeniously calculate the height of the free fall section of the slurry in the filling riser. This provides data support for optimizing pipeline design, ensuring the safe operation of the filling riser, and extending its service life.

[0011] To achieve the above-mentioned objective, this invention provides a method for rapidly testing the height of the free-fall section of slurry in a filling riser, comprising the following steps:

[0012] S1. Place the first sensor at the discharge port of the filling vertical pipe to be tested, and place the second and third sensors sequentially on the horizontal pipe after the filling vertical pipe turns into a horizontal pipe for the first time along the direction of slurry movement. The horizontal distance between the second sensor and the filling vertical pipe is X1, and the horizontal distance between the third sensor and the second sensor is X2.

[0013] S2. A test ball equipped with a signal transmitter is dropped freely from the feed port along with the slurry. The first sensor records the time T0 when the test ball falls, and the second and third sensors record the time T1 when the test ball passes the second sensor and the time T2 when it passes the third sensor, respectively. The density of the test ball is the same as that of the slurry.

[0014] S3. The vertical height of the filling vertical pipe is H, and the length of the bend of the filling vertical pipe when it first turns into the horizontal pipe is L. Based on the movement path of the slurry in the filling vertical pipe as it successively experiences the free fall section, the full pipe section, and then enters the bend and the horizontal pipe, and combined with the time recorded by each sensor, the height H1 of the free fall section of the slurry in the filling vertical pipe is calculated.

[0015] As a further improvement of the present invention, the specific calculation formula for the height H1 of the free fall segment includes:

[0016]

[0017]

[0018] Where g is the acceleration due to gravity, m / s² 2 .

[0019] As a further improvement of the present invention, in step S1, the horizontal distance X1 between the second sensor and the filling vertical pipe is 50-100m, and the horizontal distance X2 between the third sensor and the second sensor is 30-50m.

[0020] As a further improvement of the present invention, in step S1, the first sensor, the second sensor and the third sensor are arranged in pairs, and the two sensors are symmetrically arranged on the outside of the filling pipe with respect to the axis of the filling pipe.

[0021] As a further improvement of the present invention, in step S2, the test ball is a homogeneous spherical structure with a diameter of 30-45 mm.

[0022] As a further improvement of the present invention, the test ball includes an inner sphere and an outer sphere shell that surrounds the inner sphere, and the signal transmitter is placed inside the inner sphere; an adjustment solution is injected between the inner sphere and the outer sphere shell so that the density of the test ball is the same as that of the slurry.

[0023] As a further improvement of the present invention, a plurality of ribs are provided between the inner spherical chamber and the outer spherical shell to fix the inner spherical chamber, and the ribs divide the space between the inner spherical chamber and the outer spherical shell into a plurality of density regulating cavities.

[0024] As a further improvement of the present invention, the outer side of the density control cavity is provided with an injection hole, through which a control solution of different concentrations is injected into different density control cavities to achieve flexible adjustment of the density of the test ball.

[0025] As a further improvement of the present invention, the conditioning solution is an inorganic solution, including one or more of CaCl2 solution, FeCl3 solution, AlCl3 solution, and FeSO4 solution.

[0026] As a further improvement of the present invention, the inner chamber, outer shell and ribs of the test ball are all made of rubber or polymer plastic.

[0027] As a further improvement of the present invention, after calculating the height H1 of the free fall section of the slurry in the filling riser, the change of the height data guides the downhole pipeline network optimization and technical transformation work. An auxiliary device is installed in the filling riser to adjust the height of the free fall section of the slurry.

[0028] The beneficial effects of this invention are:

[0029] 1. The present invention provides a method for rapidly testing the height of the free fall section of slurry in a filling riser. First, sensors are placed at specific locations within the filling pipeline. Then, a test ball, equipped with an internal signal transmitter and having the same density as the slurry, is dropped freely from the discharge port along with the slurry. The sensors record the time taken for the test ball to travel. Finally, the height of the free fall section of the slurry in the filling riser is calculated based on the test results and known conditions. This invention uses test balls of the same density that enter the filling riser simultaneously with the slurry. Combined with the precise placement of the sensors, the test results accurately and ingeniously calculate the height of the free fall section of the slurry in the filling riser. This method does not affect production, is highly efficient and rapid, and has low cost. It provides data support for optimizing pipeline design, ensures the safe operation of the filling riser, and extends its service life.

[0030] 2. The density of the test ball in this invention is flexibly adjustable. Due to the needs of mining methods, the density of the filling slurry may vary, and the density of the test ball needs to be the same as the real-time slurry density to ensure that the movement state is the same as the slurry. However, prefabricating test balls of various densities in advance is too costly and the procedure is too complicated. This invention, through the design of the test ball structure containing several density adjustment cavities, can quickly and cost-effectively achieve density adjustment. In addition, by using the test ball in conjunction with sensors, potential high-risk areas can be detected before the pipeline is damaged, which has a better pre-monitoring effect. Measures can be taken in advance to reduce risks, significantly slowing down the wear of the vertical pipe and reducing the probability of vertical pipe burst accidents. Unlike existing borehole imaging technology, which requires waiting for obvious wear and damage before detection, it cannot play a role in early prevention and planning.

[0031] 3. This invention enables rapid, efficient, and low-cost repeated testing of the free-fall height of filling slurry in vertical pipes, identifying the locations of easily damaged vertical pipe sections during filling in different areas, i.e., the pipe locations where free fall transforms into full-pipe flow. This process is simple and repeatable, ensuring multiple flexible, efficient, and rapid tests. It provides a convenient and easy-to-implement method for on-site testing of the free-fall height of filling slurry in vertical pipes and can be widely promoted and applied in the fields of wear detection of filling vertical pipes in mines and optimization design of filling pipeline networks. Attached Figure Description

[0032] Figure 1 A schematic diagram of a method for quickly testing the height of the free fall section of slurry in a filling vertical pipe.

[0033] Figure 2 This is a structural diagram of the test ball used in the method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to the present invention.

[0034] Figure Labels

[0035] 100-Test ball; 110-Inner sphere chamber; 120-Outer sphere shell; 130-Rib plate; 140-Density control cavity; 150-Injection hole; 200-Signal transmitter; 300-First sensor; 400-Second sensor; 500-Third sensor. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0038] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0039] Please see Figure 1 As shown, a method for rapidly testing the height of the free fall section of slurry in a filling riser includes the following steps:

[0040] S1. Place the first sensor 300 at the discharge port of the filling vertical pipe to be tested. Along the direction of slurry movement, place the second sensor 400 and the third sensor 500 on the horizontal pipe after the filling vertical pipe turns into a horizontal pipe for the first time. The horizontal distance between the second sensor 400 and the filling vertical pipe is X1, and the horizontal distance between the third sensor 500 and the second sensor 400 is X2.

[0041] S2. The test ball 100, which has a signal transmitter 200 inside, is dropped freely from the feed port along with the slurry. The first sensor 300 records the time T0 when the test ball 100 falls. The second sensor 400 and the third sensor 500 record the time T1 when the test ball 100 passes through the second sensor 400 and the time T2 when it passes through the third sensor 500, respectively. The density of the test ball 100 is the same as that of the slurry.

[0042] S3. The vertical height of the filling riser is H, and the length of the bend in the filling riser when it first turns into the horizontal pipe is L. Based on the movement path of the slurry in the filling riser as it goes through the free fall section, the full pipe section, and then enters the bend and the horizontal pipe, combined with the time recorded by each sensor, the height H1 of the free fall section of the slurry in the filling riser is calculated.

[0043] As a further improvement of the present invention, the specific calculation formula for the height H1 of the free fall segment includes:

[0044]

[0045]

[0046] Where g is the acceleration due to gravity, m / s² 2 .

[0047] In particular, this invention uses test balls 100 of the same density to enter the filling riser at the same time as the slurry. With the arrangement of sensors, the height of the free fall section of the slurry in the filling riser is accurately and ingeniously calculated using the test results. This method does not affect production, is highly efficient and fast, and has low cost. It provides data support for optimizing pipeline design, ensures the safe operation of the filling riser, and extends its service life.

[0048] Specifically, in step S1, the horizontal distance X1 between the second sensor 400 and the filling riser is 50-100m, and the horizontal distance X2 between the third sensor 500 and the second sensor 400 is 30-50m. In the actual filling process, the filling slurry prepared on the surface enters the empty area through the riser, bend, and horizontal pipe to complete the filling operation. Due to reasons such as insufficient filling ratio, the filling slurry in the riser will experience a free fall section and a full pipe section before entering the bend and horizontal pipe. At the gas-liquid interface (… Figure 1 The interface marked in the image is an area on the inner wall of the pipe that is highly susceptible to damage. The second sensor 400 and the third sensor 500 are positioned to ensure sufficient distance for effective and accurate flow velocity testing.

[0049] In step S1, the first sensor 300, the second sensor 400 and the third sensor 500 are arranged in pairs. The two sensors are symmetrically arranged on the outside of the filling pipe with respect to the axis of the filling pipe. The paired sensors are conducive to accurately monitoring the transit time of the test ball 100 and reducing test errors.

[0050] Specifically, in step S2, the test ball 100 is a homogeneous spherical structure with a diameter of 30-45 mm. The homogeneous spherical structure with a diameter close to the particle size of the filling aggregate avoids the test ball 100 being subjected to resistance or other forces that interfere with the test results during the falling process.

[0051] Please see Figure 2As shown, the test sphere 100 includes an inner chamber 110 and an outer shell 120 that surrounds the inner chamber. The signal transmitter 200 is placed inside the inner chamber. A conditioning solution is poured between the inner chamber 110 and the outer shell 120 to make the density of the test sphere 100 the same as that of the slurry. Several ribs 130 are provided between the inner chamber 110 and the outer shell 120 to fix the inner chamber. The ribs 130 divide the space between the inner chamber 110 and the outer shell 120 into several density control cavities 140. A filling hole 150 is provided on the outside of the density control cavity 140. Different concentrations of conditioning solution are poured into different density control cavities 140 through the filling hole 150 to flexibly adjust the density of the test sphere 100.

[0052] The density of the test ball 100 in this invention is flexibly adjustable. Due to the needs of mining methods, the density of the filling slurry may vary, and the density of the test ball 100 needs to be the same as the real-time slurry density to achieve seamless mixing with the slurry and to match its movement. However, prefabricating test balls 100 of various densities in advance is too costly and the process is too complex. This invention, by designing the structure of the test ball 100 to include several density adjustment cavities 140, can quickly and cost-effectively achieve density adjustment. In addition, by using the test ball 100 in conjunction with sensors, potential high-risk areas can be detected before pipeline damage occurs, providing a better pre-monitoring effect. This allows for proactive measures to reduce risks, significantly slowing down the wear of vertical pipes and reducing the probability of vertical pipe bursts. Unlike existing borehole imaging technology, which requires waiting for significant wear and damage before detection and cannot provide early prevention or planning, this invention addresses these issues.

[0053] In some specific embodiments, the solution is adjusted to be an inorganic solution, including one or more of CaCl2 solution, FeCl3 solution, AlCl3 solution, and FeSO4 solution.

[0054] In some specific embodiments, the inner chamber 110, outer shell 120, and rib 130 of the test ball 100 are all made of rubber or polymer plastic. As the main consumable material of the testing method of this invention, the test ball 100, made of rubber or polymer plastic, is of low cost and is manufactured using a molding process, which is simple and reliable. Compared with borehole imaging detection methods, its cost is significantly reduced.

[0055] It should be noted that the testing method of the present invention can be repeated multiple times at low cost and quickly to accumulate a large amount of data, avoid the influence of interference factors, and calculate the height H1 of the free fall section of the slurry in the filling riser. The changes in the height data can be used to guide the optimization and technical transformation of the downhole pipeline network. For example, a resistance-increasing device can be set in the filling riser to adjust the height of the free fall section of the slurry and shorten the free fall section. Furthermore, during this optimization and debugging process, the optimization effect can be continuously verified through the testing method of the present invention.

[0056] This invention enables rapid, efficient, and low-cost repeated testing of the free-fall height of filling slurry in vertical pipes, identifying the locations of easily damaged vertical pipe sections during filling in different areas, i.e., the pipe locations where free fall transforms into full-pipe flow. The process is simple and repeatable, ensuring multiple flexible, efficient, and rapid tests. It provides a convenient and easy-to-implement method for on-site testing of the free-fall height of filling slurry in vertical pipes and can be widely promoted and applied in the fields of wear detection of filling vertical pipes in mines and optimization design of filling pipeline networks.

[0057] Example 1

[0058] This embodiment provides a method for rapidly testing the free fall height of slurry in a filling riser. The method for testing the free fall height of slurry in a filling riser in a mine includes the following steps:

[0059] S1. Place the first sensor 300 at the discharge port of the filling vertical pipe to be tested. Along the direction of slurry movement, place the second sensor 400 and the third sensor in sequence on the horizontal pipe after the filling vertical pipe turns into a horizontal pipe for the first time. The horizontal distance between the second sensor 400 and the filling vertical pipe is 100m, and the horizontal distance between the third sensor 500 and the second sensor 400 is 50m.

[0060] S2. A test ball 100, equipped with an internal signal transmitter 200, is allowed to fall freely from the feed inlet along with the slurry. The first sensor 300 records the time T0 when the test ball 100 falls, and the second sensor 400 and the third sensor 500 record the time T1 when the test ball 100 passes the second sensor 400 and the time T2 when it passes the third sensor 500, respectively. The density of the test ball 100 is the same as that of the slurry, which is 1.825 g / cm³. 3 ;

[0061] The test sphere 100 is a homogeneous sphere with a diameter of 35 mm. The main material of the test sphere 100 is rubber, comprising an inner chamber 110 and an outer shell 120 enclosing the inner chamber. The signal transmitter 200 is placed inside the inner chamber 110. Four ribs 130 are provided between the inner chamber 110 and the outer shell 120 to fix the inner chamber, dividing the space between the inner chamber 110 and the outer shell 120 into four density control cavities 140. An injection port 150 is provided on the outside of each density control cavity 140. CaCl2 adjustment solutions of different concentrations are injected into different density control cavities 140 through the injection ports 150 until a density of 1.825 g / cm³ is obtained. 3 The test ball is 100;

[0062] S3. The vertical height H of the filling riser is 240m, and the length L of the bend when the filling riser first turns into the horizontal pipe is 0.71m. Based on the movement path of the slurry in the filling riser through the free fall section, the full pipe section, and then into the bend and the horizontal pipe, combined with the time recorded by each sensor, as shown in Table 1 below, the height H1 of the free fall section of the slurry in the filling riser is calculated according to the following formula.

[0063]

[0064]

[0065] Where g is the acceleration due to gravity, m / s² 2 .

[0066] After five consecutive measurements under a certain working condition, the recording time of each sensor was obtained, and the results of T1-T0 and T2-T1 were calculated as shown in Table 1.

[0067] Table 1 shows the time parameters obtained from the five tests in Example 1.

[0068] <![CDATA[T1-T0(s)]]> <![CDATA[T2-T1(s)]]> first 180.12 31.27 The second 180.15 31.22 The third 180.14 31.24 Fourth 180.13 31.23 Fifth 180.16 31.23

[0069] Based on formulas (1) and (2) and the data in Table 1, the height of the free fall section of the slurry in the filling vertical pipe of Example 1 is calculated as shown in the table below.

[0070] Table 2 Results of the test on the free fall height of slurry in the filling vertical pipe in Example 1

[0071]

[0072] As shown in Table 2, the five test results obtained by using the rapid testing method of the present invention to test the height of the free fall section of the slurry in the filling vertical pipe are similar, indicating that the method can quickly and efficiently test the height of the free fall section of the slurry, and has good accuracy and small error.

[0073] In summary, the present invention provides a method for rapidly testing the height of the free fall section of slurry in a filling riser. First, sensors are arranged at specific locations in the filling pipeline. Then, a test ball with a signal transmitter inside and the same density as the slurry is dropped freely from the discharge port along with the slurry. The time taken for the test ball to pass through the pipeline is recorded by each sensor. Finally, the height of the free fall section of slurry in the filling riser is calculated based on the test results and known conditions. This invention employs a test ball of the same density to simultaneously enter the filling riser with the slurry. By carefully positioning the sensors, the height of the slurry's free-fall section within the filling riser is accurately and ingeniously calculated using the test results. This method allows for rapid, efficient, and low-cost repeated testing, identifying the locations of sections of the riser prone to damage during filling in different areas—specifically, the locations where free fall transforms into full-pipe flow. This provides data support for optimizing pipeline network design, ensuring the safe operation of filling risers, and extending their service life. Furthermore, the process is simple and easily repeatable, ensuring multiple, flexible, efficient, and rapid tests. This method does not affect production, is highly efficient, fast, and low-cost, providing a convenient and easy-to-implement means for on-site testing of the slurry's free-fall height in filling risers. It can be widely applied in the fields of mine filling riser wear detection and filling pipeline network optimization design.

[0074] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe, characterized in that, Includes the following steps: S1. Place the first sensor at the discharge port of the filling vertical pipe to be tested, and place the second and third sensors sequentially on the horizontal pipe after the filling vertical pipe turns into a horizontal pipe for the first time along the direction of slurry movement. The horizontal distance between the second sensor and the filling vertical pipe is X1, and the horizontal distance between the third sensor and the second sensor is X2. S2. A test ball equipped with a signal transmitter is dropped freely from the feed port along with the slurry. The first sensor records the time T0 when the test ball falls, and the second and third sensors record the time T1 when the test ball passes the second sensor and the time T2 when it passes the third sensor, respectively. The density of the test ball is the same as that of the slurry. S3. The vertical height of the filling vertical pipe is H, and the length of the bend of the filling vertical pipe when it first turns into the horizontal pipe is L. Based on the movement path of the slurry in the filling vertical pipe as it successively experiences the free fall section, the full pipe section, and then enters the bend and the horizontal pipe, and combined with the time recorded by each sensor, the height H1 of the free fall section of the slurry in the filling vertical pipe is calculated.

2. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 1, characterized in that, The specific formula for calculating the height H1 of the free fall segment includes: Where g is the acceleration due to gravity, m / s² 2 .

3. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 1, characterized in that, In step S1, the horizontal distance X1 between the second sensor and the filling vertical pipe is 50-100m, and the horizontal distance X2 between the third sensor and the second sensor is 30-50m.

4. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 1, characterized in that, In step S1, the first sensor, the second sensor, and the third sensor are arranged in pairs, with the two sensors symmetrically positioned on the outside of the filling pipe along its axis.

5. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 1, characterized in that, In step S2, the test ball is a homogeneous spherical structure with a diameter of 30-45 mm.

6. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 5, characterized in that, The test sphere includes an inner chamber and an outer shell that surrounds the inner chamber. The signal transmitter is placed inside the inner chamber. An adjusting solution is poured between the inner chamber and the outer shell to make the density of the test sphere the same as that of the slurry.

7. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 6, characterized in that, A number of ribs are provided between the inner spherical chamber and the outer spherical shell to fix the inner spherical chamber, and the ribs divide the space between the inner spherical chamber and the outer spherical shell into a number of density regulating cavities.

8. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 7, characterized in that, The density control cavity is provided with an injection hole on its outer side. Different concentrations of adjustment solutions are injected into different density control cavities through the injection hole to flexibly adjust the density of the test ball.

9. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 6, characterized in that, The conditioning solution is an inorganic solution, including one or more of CaCl2 solution, FeCl3 solution, AlCl3 solution, and FeSO4 solution.

10. The method for rapidly testing the height of the free fall section of slurry in a filling vertical pipe according to claim 7, characterized in that, The inner chamber, outer shell, and ribs of the test ball are all made of rubber or polymer plastic.

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