A shotcrete uniformity control nozzle and method

Abstract

The application discloses a kind of shotcrete uniformity control spray head and method, the spray head includes spray head main pipe, concrete channel and inside and outside two-stage gas channel, second atomizing nozzle is provided on spray head main pipe, conical structure gas distribution device is provided in horn pipe, there is annular discharge port between horn pipe and concrete channel outlet end, multiple direct-flow air injection holes are uniformly provided on spray head end face;The method includes the following steps: one, gas cyclone acceleration is sprayed with quick-setting agent;Two, direct-flow uniform spraying of gas with quick-setting agent;Three, access concrete;Four, the first uniform mixing of quick-setting agent and concrete;Five, the second uniform mixing of quick-setting agent and concrete and uniformly sprayed to working face.The application is reasonably combined by gas material quick-setting agent, and cyclone wind is used for concrete rotation to scatter in the inside of spray head end face, and multiple direct-flow air is used for spraying, so that concrete is more effectively dispersed at the outlet of spray head, and the sprayed discharge is more uniform.

Description

Technical Field

[0001] This invention belongs to the field of shotcrete spraying technology, specifically relating to a spray nozzle and method for controlling the uniformity of shotcrete. Background Technology

[0002] Shotcrete has advantages such as fast setting and hardening speed, high early strength, high construction efficiency and simple process, and is widely used in various engineering projects.

[0003] In current shotcrete construction, due to the unsmooth air-material combination of the nozzle, there are problems such as jamming, intermittent material discharge, and more material in the center of the pipe than at the edge. This results in uneven material discharge, causing uneven thickness and uneven surface after spraying, which seriously affects the construction quality.

[0004] In addition, existing liquid quick-setting agents are generally added at the nozzle and mixed with the concrete inside the nozzle before being sprayed out. If the quick-setting agent and the concrete at the nozzle are not properly controlled, the concrete at the nozzle will harden, causing blockage of the nozzle and pump pipe, poor material discharge, and making it impossible to carry out construction continuously, which seriously affects the efficiency of shotcrete construction.

[0005] Therefore, it is necessary to optimize the design of shotcrete nozzles to make the combination of air, material, and accelerator more reasonable and meet the requirements of continuous and stable construction. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the shortcomings of the prior art by providing a sprayed concrete uniformity control nozzle. Its design is novel and reasonable. By combining air, material, and accelerator in a reasonable way, the concrete is more effectively dispersed at the nozzle outlet, resulting in more uniform spraying. It also solves the technical problem of accelerator hardening and clogging of the nozzle, effectively improving the quality and efficiency of sprayed concrete construction. It can adapt to the needs of various sprayed concrete construction projects and is suitable for large-scale promotion and use in engineering.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a sprayed concrete uniformity control nozzle, characterized in that: it includes a nozzle main pipe and a concrete channel with a frustum-shaped structure disposed within the nozzle main pipe, the inlet end size of the concrete channel being larger than the outlet end size of the concrete channel, the inlet end of the nozzle main pipe and the concrete channel being connected as one unit by a first connecting flange, the outlet end of the nozzle main pipe and the concrete channel being connected by a nozzle end face, a primary gas channel passing through the inlet end sidewall of the nozzle main pipe and the concrete channel and disposed within the concrete channel, and the nozzle main pipe being provided with multiple secondary gas channels, each communicating with the gap between the nozzle main pipe and the concrete channel. The gas channel includes a horizontal pipe installed horizontally within a concrete channel. A horn-shaped pipe is installed at the outlet end of the horizontal pipe near the concrete channel, and a connecting pipe is installed at the inlet end of the horizontal pipe near the concrete channel. One end of the connecting pipe extends outward from the nozzle main pipe and is connected to an air inlet hose, on which a first atomizing nozzle is installed. Multiple second atomizing nozzles extending into the gap between the nozzle main pipe and the concrete channel are installed on the nozzle main pipe. A conical gas distribution device is installed inside the horn-shaped pipe. The end plane of the gas distribution device is connected to the end wall of the horn-shaped pipe through multiple connecting plates. An annular discharge port is located between the horn-shaped pipe and the outlet end of the concrete channel. Multiple direct-flow jet holes are evenly arranged on the nozzle end face.

[0008] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: the section of the horizontal pipe near the outlet end of the concrete channel is connected to the inner wall of the concrete channel via a connecting rod.

[0009] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: a second connecting flange is provided at the inlet end of the secondary gas channel.

[0010] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: the secondary gas channel is located outside the nozzle main pipe, and the angle between the central axis of the secondary gas channel and the central axis of the nozzle main pipe is 20° to 35°; the number of secondary gas channels is three, and two adjacent secondary gas channels are evenly arranged at 120° around the nozzle main pipe.

[0011] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: the apex angle of the concrete channel is 10° to 20°.

[0012] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: the number of the second atomizing nozzles is 4 to 6, the 4 to 6 second atomizing nozzles are evenly arranged at equal angles around the nozzle main pipe, and the 4 to 6 second atomizing nozzles are located at the point where the cross-sectional area of ​​the secondary gas channel is the smallest.

[0013] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: the connecting plate is arranged at an angle, and a swirling jet hole is formed between two adjacent connecting plates. Multiple swirling jet holes are evenly distributed at equal angles around the end plane of the air distribution device and the end wall of the trumpet tube. The air outlet direction of each swirling jet hole is a straight line tangent to the corresponding arc segment. The air outlet direction of multiple swirling jet holes is clockwise or counterclockwise. The number of swirling jet holes is 8 to 12.

[0014] The above-mentioned sprayed concrete uniformity control nozzle is characterized in that: three rings of DC air jet holes are evenly arranged on the end face of the nozzle, and multiple DC air jet holes in each ring are evenly distributed at equal angles on the end face of the nozzle. The number of DC air jet holes in each ring is 15 to 18, and the DC air jet holes in adjacent rings are staggered. The air outlet direction of the DC air jet holes is a horizontal straight line.

[0015] Meanwhile, this invention also discloses a method for controlling the uniformity of shotcrete, characterized by the following steps:

[0016] Step 1: The gas carrying the accelerator is accelerated and ejected in a swirling stream, as follows:

[0017] Step 101: Connect the inlet hose at the primary gas channel inlet to the compressed air to complete the gas access;

[0018] Step 102: Open the first atomizing nozzle connected to the inlet on the outside of the primary gas channel, and spray the liquid quick-setting agent into the primary gas channel in a mist evenly. The atomized quick-setting agent is fully mixed with the gas, and the dispersion effect of the atomized quick-setting agent is good.

[0019] Step 103: The gas carrying the accelerator flows to the outlet of the primary gas channel. After being impacted by the cone of the conical gas distributor, the gas is further dispersed and flows evenly to the annular gas outlet channel around the gas distributor. As the cross-sectional area of ​​the annular gas outlet channel becomes smaller, the gas flow velocity gradually increases. The accelerated gas carrying the accelerator is then ejected through the swirling jet nozzle to complete the gas swirling acceleration.

[0020] Step 2: The gas carrying the accelerator is sprayed out evenly in a straight line, as follows:

[0021] Step 201: Connect the multiple secondary gas channels to compressed air through the second connecting flange at the inlet to complete the gas access;

[0022] Step 202: Open the second atomizing nozzles that are evenly arranged around the outer side of the secondary gas channel, and spray the liquid quick-setting agent into the secondary gas channel in a mist. The quick-setting agent is added at the smallest diameter of the secondary gas channel to achieve the best dispersion in a small area. The atomized quick-setting agent is fully and evenly mixed with the gas, and the dispersion effect of the atomized quick-setting agent is good.

[0023] Step 203: The gas carrying the quick-setting agent flows to the outlet of the secondary gas channel. Here, due to the increased pipe diameter, the gas flow rate is slower, and the gas can flow evenly to multiple DC jet holes located on the nozzle end face. Thus, the gas is evenly distributed by multiple evenly arranged DC jet holes and the gas is uniformly ejected in DC direction.

[0024] Step 3: Connecting Concrete: Connect the concrete channel to the concrete pump pipe through the first connecting flange. Concrete enters the concrete channel through the pump pipe. Since the diameter of the concrete channel gradually decreases, it accelerates the concrete delivery. The concrete in the channel is squeezed and flows towards the annular discharge port. When the concrete flows out of the annular discharge port, the initial velocity of the concrete is relatively small.

[0025] Step 4: Uniform Mixing of Accelerator and Concrete in One Step: The gas carrying the accelerator is accelerated and sprayed out in a swirling motion. The tangential swirling air comes into contact with the concrete flowing out through the annular outlet. The concrete is dispersed by the tangential swirling air. While the accelerator in the gas and the concrete are uniformly mixed, the swirling air blown in their respective tangential directions rotates the concrete in the annular channel evenly to the outer ring of the nozzle end face, bringing the concrete into the direct current spraying area. Because the initial velocity of the concrete is relatively small when it flows out of the annular outlet, the gas carrying the accelerator has enough time to mix with the concrete. And due to the swirling air's dispersing effect, the gas can come into more uniform contact with the dispersed concrete, achieving uniform mixing of the accelerator and concrete in one step.

[0026] Step 5: Secondary uniform mixing of accelerator and concrete and uniform spraying onto the working surface: The gas carrying the accelerator is sprayed out evenly in a direct current to the direct current spraying area, making full and uniform contact with the concrete entering this area. This allows the accelerator in the gas to be fully mixed with the dispersed concrete, completing the secondary uniform mixing of the accelerator and concrete. The horizontal direct current blown out can push the secondary uniformly mixed sprayed concrete onto the spraying working surface, completing the long-distance spraying operation of concrete.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] 1. The nozzle used in this invention changes the traditional mixing mode of accelerator and concrete inside the nozzle. The mixing process is moved to the outside of the nozzle, and the accelerator and concrete do not come into contact inside the nozzle. This solves the problem of nozzle blockage caused by the accelerator hardening with the concrete at the nozzle due to air pressure decay or poor material discharge. It also changes the traditional method of pneumatically conveying concrete inside the nozzle. There is no gas inside the nozzle to accelerate the spraying of concrete. The concrete flows forward only by the gradually decreasing diameter of the concrete pipe and the residual pressure of the front-end delivery pump. That is, the air and material do not come into contact inside the nozzle, but are combined outside the nozzle, which is convenient for widespread use.

[0029] 2. The nozzle used in this invention achieves uniform mixing of gas and accelerator inside the nozzle through an atomizing nozzle for accelerator. Through primary gas mixing, secondary gas mixing, and concrete-accelerator mixing, the accelerator and gas, and gas and concrete are thoroughly and uniformly mixed respectively. At the same time as the concrete is discharged from the nozzle, the accelerator and concrete are uniformly mixed, ensuring the construction effect after construction.

[0030] 3. The method adopted in this invention is simple in steps. Since the initial velocity of the concrete flowing out of the annular outlet is relatively small, the swirling air carrying the accelerator has sufficient time to mix and contact with the concrete. In addition, due to the rotational and dispersing effect of the swirling air, the gas can contact the dispersed concrete more evenly, achieving a first uniform mixing of the accelerator and the concrete. Due to the large number of direct jet nozzles, the dozens of direct jets blown out can fully and evenly contact the concrete entering this area, allowing the accelerator in the gas to fully mix with the dispersed concrete, completing a second uniform mixing of the accelerator and the concrete. By rationally combining the gas-material-accelerator, setting the innermost swirling air on the nozzle end face for rotating and dispersing the concrete, and using multiple staggered direct jets for spraying, the concrete is more effectively dispersed at the nozzle outlet, making the sprayed material more uniform and easy to promote and use.

[0031] In summary, this invention is novel and reasonable in design. By rationally combining air, material, and accelerator, it enables concrete to be more effectively dispersed at the nozzle outlet, resulting in more uniform spraying. It also solves the technical problem of accelerator hardening and clogging the nozzle, effectively improving the quality and efficiency of shotcrete construction. Furthermore, it can adapt to various shotcrete construction needs and is suitable for large-scale promotion and use in engineering projects, making it easy to promote and apply.

[0032] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure and connection of the nozzle of the present invention.

[0034] Figure 2 This is a schematic diagram showing the structural connection between the secondary gas channel and the nozzle main pipe of the present invention.

[0035] Figure 3 This is a schematic diagram showing the structural connection of the gas distribution device, the annular outlet, and the nozzle end face of the present invention.

[0036] Figure 4 This is a schematic diagram of the structural connection of the primary gas channel of the present invention.

[0037] Figure 5 This is a flowchart of the method of the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1—Connecting rod; 2—Nozzle main pipe; 3—Primary gas passage;

[0040] 4—Secondary gas channel; 5—Nozzle end face; 6—Concrete channel;

[0041] 7—First connecting flange; 8—Annular discharge port; 9—Air inlet hose;

[0042] 10—Gas distribution device; 11—Swirl jet nozzle; 12—First atomizing nozzle;

[0043] 13—Second connecting flange; 14—DC jet nozzle; 15—Connecting plate;

[0044] 16—Connecting pipe; 17—Horizontal pipe; 18—Bell-shaped pipe;

[0045] 19—Second atomizing nozzle. Detailed Implementation

[0046] like Figures 1 to 4As shown, the sprayed concrete uniformity control nozzle of the present invention includes a nozzle main pipe 2 and a concrete channel 6 with a frustum-shaped structure disposed within the nozzle main pipe 2. The inlet end size of the concrete channel 6 is larger than the outlet end size of the concrete channel 6. The nozzle main pipe 2 and the inlet end of the concrete channel 6 are connected as one unit by a first connecting flange 7. The outlet end of the nozzle main pipe 2 and the concrete channel 6 are connected by a nozzle end face 5. A primary gas channel 3 is disposed within the concrete channel 6, passing through the inlet end sidewall of the nozzle main pipe 2 and the concrete channel 6. The nozzle main pipe 2 is provided with a plurality of secondary gas channels 4, each communicating with the gap between the nozzle main pipe 2 and the concrete channel 6. The primary gas channel 3 includes a horizontally disposed section within the concrete channel 6. A horizontal pipe 17 is provided with a horn pipe 18 at the outlet end of the horizontal pipe 17 near the concrete channel 6, and a connecting pipe 16 is provided at the inlet end of the horizontal pipe 17 near the concrete channel 6. One end of the connecting pipe 16 extends outward from the nozzle main pipe 2 and is connected to an air inlet hose 9, on which a first atomizing nozzle 12 is provided. Multiple second atomizing nozzles 19 are provided on the nozzle main pipe 2, extending into the gap between the nozzle main pipe 2 and the concrete channel 6. A conical air distribution device 10 is provided inside the horn pipe 18. The end plane of the air distribution device 10 is connected to the end wall of the horn pipe 18 through multiple connecting plates 15. There is an annular discharge port 8 between the horn pipe 18 and the outlet end of the concrete channel 6. Multiple direct jet holes 14 are evenly provided on the nozzle end face 5.

[0047] It should be noted that the shotcrete uniformity control nozzle changes the traditional method of mixing the accelerator and concrete inside the nozzle. The mixing process is moved to the outside of the nozzle, where the accelerator and concrete do not come into contact inside. This solves the problem of nozzle blockage caused by the accelerator hardening and solidifying with the concrete at the nozzle due to air pressure decay or poor discharge. It also changes the traditional method of pneumatically conveying concrete inside the nozzle. Instead of using gas to accelerate the spraying of concrete, the concrete flows forward solely due to the gradually decreasing diameter of the concrete pipe and the residual pressure of the front-end pump. In other words, the air and material do not come into contact inside the nozzle, but rather the air-material combination is placed outside. The uniform mixing of gas and accelerator inside the nozzle is achieved through an atomizing nozzle. Furthermore, through primary gas mixing, secondary gas mixing, and concrete-accelerator mixing, thorough and uniform mixing of the accelerator and gas, and gas and concrete is achieved respectively. The uniform mixing of the accelerator and concrete is completed simultaneously with the concrete discharge from the nozzle, ensuring the best post-construction results.

[0048] In this embodiment, the section of the horizontal pipe 17 near the outlet end of the concrete channel 6 is connected to the inner wall of the concrete channel 6 via a connecting rod 1.

[0049] In practical use, the concrete passage 6 is made of wear-resistant steel plate or wear-resistant plastic material, which can effectively reduce the wear of concrete on it.

[0050] The concrete channel 6 is equipped with a first connecting flange 7 at the inlet end. When feeding, the first connecting flange 7 is connected to the concrete pump pipe. When discharging, the material is discharged through the annular discharge port 8 located on the nozzle end face 5.

[0051] Specifically, when cleaning the concrete channel 6, the first connecting flange 7 is connected to the water pipe, and after cleaning the concrete channel 6, the water is discharged through the annular outlet 8 on the nozzle end face 5.

[0052] In this embodiment, a second connecting flange 13 is provided at the inlet end of the secondary gas channel 4.

[0053] In this embodiment, the secondary gas channel 4 is located outside the nozzle main pipe 2, and the angle between the central axis of the secondary gas channel 4 and the central axis of the nozzle main pipe 2 is 20° to 35°. There are three secondary gas channels 4, and two adjacent secondary gas channels 4 are evenly arranged at 120° around the nozzle main pipe 2.

[0054] The air inlet of the secondary gas channel 4 is connected to compressed air through the second connecting flange 13, and the gas is ejected through the DC jet hole 14 located on the nozzle end face 5.

[0055] Specifically, the diameter of the secondary gas channel 4 first decreases and then increases, with the largest diameter at the inlet, then gradually decreasing, and gradually increasing again at the outlet of the DC jet hole 14.

[0056] In this embodiment, the apex angle of the concrete channel 6 is 10° to 20°.

[0057] In this embodiment, the number of the second atomizing nozzles 19 is 4 to 6. The 4 to 6 second atomizing nozzles 19 are evenly arranged at equal angles around the nozzle main tube 2, and the 4 to 6 second atomizing nozzles 19 are located at the point where the cross-sectional area of ​​the secondary gas channel 4 is the smallest.

[0058] In this embodiment, the connecting plate 15 is arranged at an angle, and a swirling jet hole 11 is formed between two adjacent connecting plates 15. Multiple swirling jet holes 11 are evenly distributed at equal angles around the end plane of the air distribution device 10 and the end wall of the horn tube 18. The air outlet direction of each swirling jet hole 11 is a straight line direction tangent to the corresponding arc segment. The air outlet direction of multiple swirling jet holes 11 is clockwise or counterclockwise. The number of swirling jet holes 11 is 8 to 12.

[0059] It should be noted that a gas distributor 10 is provided at the outlet of the primary gas channel 3. The gas distributor 10 is conical, with its bottom fixed to the nozzle end face 5 and its top arranged opposite to the air inlet direction. The gas exiting the primary gas channel 3 passes through the annular outlet channel surrounding the gas distributor 10 and is finally ejected through the swirling jet nozzle 11 located on the nozzle end face 5. Specifically, the diameter of the primary gas channel 3 first increases and then decreases, with a smaller diameter at the vertical inlet and a larger diameter at the horizontal pipe, gradually decreasing as it passes through the annular outlet channel surrounding the gas distributor 10.

[0060] In this embodiment, three rings of DC jet holes 14 are evenly arranged on the nozzle end face 5. In each ring, multiple DC jet holes 14 are evenly distributed at equal angles on the nozzle end face 5. The number of DC jet holes 14 in each ring is 15 to 18. The DC jet holes 14 in adjacent rings are staggered. The air outlet direction of the DC jet holes 14 is a horizontal straight line.

[0061] like Figure 5 The method for controlling the uniformity of shotcrete, as shown, includes the following steps:

[0062] Step 1: The gas carrying the accelerator is accelerated and ejected in a swirling stream, as follows:

[0063] Step 101: Connect the air inlet hose 9 at the inlet of the primary gas channel 3 to compressed air to complete the gas access;

[0064] Step 102: Open the first atomizing nozzle 12 connected to the outer inlet of the primary gas channel 3, and spray the liquid quick-setting agent into the primary gas channel 3 in a mist evenly. The atomized quick-setting agent is fully mixed with the gas, and the dispersion effect of the atomized quick-setting agent is good.

[0065] Step 103: The gas carrying the quick-setting agent flows to the outlet of the primary gas channel 3. After the gas is impacted by the cone of the conical gas distributor 10, it becomes more dispersed and flows evenly to the annular gas outlet channel around the gas distributor 10. As the cross-sectional area of ​​the annular gas outlet channel becomes smaller, the gas flow rate gradually increases. The accelerated gas carrying the quick-setting agent is then ejected through the swirling jet hole 11 to complete the gas swirling acceleration.

[0066] Because the inlet diameter at the front end of the primary gas channel 3 is small, the quick-setting agent can achieve the best dispersion in a small area, which is conducive to the uniform combination of the quick-setting agent and the gas. The quick-setting agent is uniformly added into the primary gas channel 3 through the first atomizing nozzle 12, and completes the uniform mixing with the gas in the inlet channel.

[0067] Step 2: The gas carrying the accelerator is sprayed out evenly in a straight line, as follows:

[0068] Step 201: Connect the multiple secondary gas channels 4 to compressed air through the second connecting flange 13 at the inlet to complete the gas access;

[0069] Step 202: Open the second atomizing nozzles 19 that are evenly arranged around the outer side of the secondary gas channel 4, and spray the liquid quick-setting agent into the secondary gas channel 4 in a mist. The quick-setting agent is added at the smallest diameter of the secondary gas channel 4 to achieve the best dispersion in a small area. The atomized quick-setting agent is fully and evenly mixed with the gas, and the dispersion effect of the atomized quick-setting agent is good.

[0070] Step 203: The gas carrying the quick-setting agent flows to the outlet of the secondary gas channel 4. Here, due to the increased pipe diameter, the gas flow rate is slower, and the gas can flow evenly to the multiple DC jet holes 14 located on the nozzle end face 5. Thus, the gas is evenly distributed by the multiple evenly arranged DC jet holes 14 and the gas is evenly ejected in DC direction.

[0071] Step 3, Introducing Concrete: Connect the concrete channel 6 to the concrete pump pipe through the first connecting flange 7. Concrete enters the concrete channel 6 through the pump pipe. Since the diameter of the concrete channel 6 gradually decreases, it accelerates the concrete delivery. The concrete in the channel is squeezed and flows towards the annular discharge port 8. When the concrete flows out of the annular discharge port 8, the initial velocity of the concrete is relatively small.

[0072] Step 4: Uniform mixing of accelerator and concrete in one step: The gas carrying the accelerator is accelerated and sprayed out in a swirling stream. The tangential swirling air comes into contact with the concrete flowing out through the annular outlet 8. The concrete is dispersed by the tangential swirling air. While the accelerator in the gas and the concrete are uniformly mixed, the swirling air blown in their respective tangential directions rotates the concrete in the annular channel evenly to the outer ring of the nozzle end face 5, bringing the concrete into the direct current spraying area. Since the initial velocity of the concrete is relatively small when it flows out of the annular outlet 8, the gas carrying the accelerator has enough time to mix with the concrete. And due to the swirling air's dispersing effect, the gas can come into more uniform contact with the dispersed concrete, achieving uniform mixing of the accelerator and concrete in one step.

[0073] Step 5: Secondary uniform mixing of accelerator and concrete and uniform spraying onto the working surface: The gas carrying the accelerator is sprayed out evenly in a direct current to the direct current spraying area, making full and uniform contact with the concrete entering this area. This allows the accelerator in the gas to be fully mixed with the dispersed concrete, completing the secondary uniform mixing of the accelerator and concrete. The horizontal direct current blown out can push the secondary uniformly mixed sprayed concrete onto the spraying working surface, completing the long-distance spraying operation of concrete.

[0074] When this invention is used, the initial velocity of the concrete flowing out of the annular outlet is relatively low, allowing the swirling air carrying the accelerator sufficient time to mix and contact with the concrete. Furthermore, the rotating and dispersing effect of the swirling air ensures more uniform contact between the gas and the dispersed concrete, achieving a primary uniform mixing of the accelerator and concrete. Due to the large number of direct-flow jet nozzles, dozens of streams of direct-flow air make full and uniform contact with the concrete entering this area, ensuring thorough mixing of the accelerator in the gas with the dispersed concrete, completing a secondary uniform mixing. By rationally combining the gas, material, and accelerator, and by setting a swirling airflow at the innermost side of the nozzle end face for rotating and dispersing the concrete, and multiple staggered direct-flow airflows for spraying, the concrete is more effectively dispersed at the nozzle outlet, resulting in more uniform spraying and improving the quality and efficiency of shotcrete construction. This also adapts to various shotcrete construction needs.

[0075] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A spray nozzle for controlling the uniformity of shotcrete, characterized in that: The system includes a nozzle main pipe (2) and a truncated cone-shaped concrete channel (6) located inside the nozzle main pipe (2). The inlet size of the concrete channel (6) is larger than the outlet size. The inlet ends of the nozzle main pipe (2) and the concrete channel (6) are connected as one unit by a first connecting flange (7). The outlet ends of the nozzle main pipe (2) and the concrete channel (6) are connected by a nozzle end face (5). A primary gas channel (3) passes through the inlet sidewall of the nozzle main pipe (2) and the concrete channel (6) and is located inside the concrete channel (6). The nozzle main pipe (2) is provided with multiple secondary gas channels (4) that are connected to the gap between the nozzle main pipe (2) and the concrete channel (6). The primary gas channel (3) includes a horizontal pipe (17) horizontally located inside the concrete channel (6). The horizontal pipe (17) is located near the... A horn tube (18) is provided at the outlet end of the concrete channel (6). A connecting pipe (16) is provided at the inlet end of the horizontal pipe (17) near the concrete channel (6). The connecting pipe (16) extends out of the outside of the nozzle main pipe (2) and is connected to an air inlet hose (9) and a first atomizing nozzle (12) is provided on it. Multiple second atomizing nozzles (19) are provided on the nozzle main pipe (2) and extend into the gap between the nozzle main pipe (2) and the concrete channel (6). A conical air distribution device (10) is provided inside the horn tube (18). The end plane of the air distribution device (10) is connected to the end wall of the horn tube (18) through multiple connecting plates (15). There is an annular discharge port (8) between the horn tube (18) and the outlet end of the concrete channel (6). Multiple direct jet holes (14) are evenly provided on the nozzle end face (5). The connecting plate (15) is arranged at an angle, and a swirling jet hole (11) is formed between two adjacent connecting plates (15). Multiple swirling jet holes (11) are evenly distributed at equal angles around the end plane of the gas distribution device (10) and the end wall of the horn tube (18). The air outlet direction of each swirling jet hole (11) is a straight line tangent to the corresponding arc segment. The air outlet direction of multiple swirling jet holes (11) is clockwise or counterclockwise. The number of swirling jet holes (11) is 8 to 12.

2. A sprayed concrete uniformity control nozzle according to claim 1, characterized in that: The section of the horizontal pipe (17) near the outlet end of the concrete channel (6) is connected to the inner wall of the concrete channel (6) via a connecting rod (1).

3. A sprayed concrete uniformity control nozzle according to claim 1, characterized in that: The inlet end of the secondary gas channel (4) is provided with a second connecting flange (13).

4. A sprayed concrete uniformity control nozzle according to claim 1, characterized in that: The secondary gas channel (4) is located outside the nozzle main pipe (2), and the angle between the central axis of the secondary gas channel (4) and the central axis of the nozzle main pipe (2) is 20° to 35°. There are three secondary gas channels (4), and two adjacent secondary gas channels (4) are evenly arranged at 120° around the nozzle main pipe (2).

5. A sprayed concrete uniformity control nozzle according to claim 1, characterized in that: The apex angle of the concrete channel (6) is 10° to 20°.

6. A sprayed concrete uniformity control nozzle according to claim 1, characterized in that: The number of the second atomizing nozzles (19) is 4 to 6. The 4 to 6 second atomizing nozzles (19) are evenly arranged at equal angles around the nozzle main tube (2), and the 4 to 6 second atomizing nozzles (19) are located at the point where the cross-sectional area of ​​the secondary gas channel (4) is the smallest.

7. A sprayed concrete uniformity control nozzle according to claim 1, characterized in that: Three rings of DC jet holes (14) are evenly arranged on the nozzle end face (5). Multiple DC jet holes (14) in each ring are evenly distributed at equal angles on the nozzle end face (5). The number of DC jet holes (14) in each ring is 15 to 18. The DC jet holes (14) in adjacent rings are staggered. The air outlet direction of the DC jet holes (14) is a horizontal straight line.

8. A method for controlling the uniformity of shotcrete using the nozzle as described in claim 1, characterized in that: The method includes the following steps: Step 1: The gas carrying the accelerator is accelerated and ejected in a swirling stream, as follows: Step 101: Connect the air inlet hose (9) at the inlet of the primary gas channel (3) to compressed air to complete the gas access; Step 102: Open the first atomizing nozzle (12) connected to the outer inlet of the primary gas channel (3) and spray the liquid quick-setting agent into the primary gas channel (3) in a mist form. The atomized quick-setting agent is fully mixed with the gas. Step 103: The gas carrying the quick-setting agent flows to the outlet of the primary gas channel (3). After the gas is impacted by the cone of the conical gas distributor (10), it becomes more dispersed and flows evenly to the annular gas outlet channel around the gas distributor (10). As the cross-sectional area of ​​the annular gas outlet channel becomes smaller, the gas flow rate gradually increases. The accelerated gas carrying the quick-setting agent is then accelerated and ejected through the swirling jet hole (11). Step 2: The gas carrying the accelerator is sprayed out evenly in a straight line, as follows: Step 201: Connect the multiple secondary gas channels (4) to compressed air through the second connecting flange (13) at the inlet to complete the gas access; Step 202: Open the second atomizing nozzles (19) evenly arranged around the outer side of the secondary gas channel (4) and spray the liquid quick-setting agent into the secondary gas channel (4) in a mist. The quick-setting agent is added at the smallest diameter of the secondary gas channel (4). Step 203: The gas carrying the quick-setting agent flows to the outlet of the secondary gas channel (4). Due to the increased pipe diameter, the gas flow rate is slower here. The gas can flow evenly to the multiple DC jet holes (14) located on the nozzle end face (5). Thus, the gas is evenly distributed by the multiple evenly arranged DC jet holes (14) and the gas is evenly ejected in DC direction. Step 3, Introduce Concrete: Connect the concrete channel (6) to the concrete pump pipe through the first connecting flange (7), and the concrete enters the concrete channel (6) through the pump pipe; Step 4: Uniform mixing of quick-setting agent and concrete: The gas carrying quick-setting agent is accelerated and sprayed out in a swirling stream. The tangential swirling air blown out comes into contact with the concrete flowing out through the annular outlet (8). The concrete is rotated and dispersed by the tangential swirling air. While the quick-setting agent and concrete in the gas are uniformly mixed, the swirling air blown out in their respective tangential directions rotates the concrete in the annular channel uniformly to the outer ring of the nozzle end face (5), bringing the concrete into the direct current air blowing area, thus realizing a uniform mixing of quick-setting agent and concrete in one step. Step 5: Secondary uniform mixing of accelerator and concrete and uniform spraying onto the working surface: The gas carrying the accelerator is sprayed out evenly in a direct current to the direct current spraying area, making full and uniform contact with the concrete entering this area. This allows the accelerator in the gas to be fully mixed with the dispersed concrete, completing the secondary uniform mixing of the accelerator and concrete. The horizontal direct current blown out can push the secondary uniformly mixed sprayed concrete onto the spraying working surface, completing the long-distance spraying operation of concrete.

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