A device and method for coating inner walls of narrow and long spaces

Abstract

The present invention discloses a device and method for painting the inner wall of a narrow and long space. The device includes a paint spray gun device with multiple compressed air chambers, the paint spray gun device is connected to a suspendable delivery nested hose group, the delivery nested hose group is respectively connected to the nozzle of each compressed air chamber; the outlet of the delivery nested hose group is provided with a paint atomization guide assembly. When in use, the delivery nested hose group is assembled, and the multiple starting ends of the delivery nested hose group are respectively connected to the nozzles of multiple compressed air chambers; the paint atomization guide assembly is installed at the outlet of the delivery nested hose group; one of the compressed air chambers ventilates the outermost hose of the delivery nested hose group, so that the other end of the delivery nested hose group floats; the remaining compressed air chambers ventilate the inner hose of the delivery nested hose group, and spray paint through the paint atomization guide assembly at the other end. It can eliminate the quality problem of uneven coating thickness caused by the paint filling process of the oil mist sealing component of the main pump motor.

Description

Technical Field

[0001] The invention relates to a device and method for coating the inner wall of a narrow and long space, belonging to the technical field of coating. Background Art

[0002] The main pump motor is a critical component in the reactor coolant pump. It is the only continuously operating device in a nuclear power plant's main circuit system and the heart of the plant, playing a vital role in ensuring the safe circulation of the main coolant. The oil mist seal in the bearing chamber is a crucial component. The stability of its sealing function directly determines the lubricating oil level within the main pump motor's bearing chamber, significantly impacting the long-term safe operation of the main pump motor. Therefore, the inner cavity of the oil mist seal requires rust-proof coating, applying an oil mist-repellent coating to maintain a good oil mist seal. However, to achieve a good seal, the oil mist seal is typically designed with a narrow channel to increase sealing pressure, which poses significant challenges in its manufacturing, especially in the inner cavity coating process. Conventional coating methods use a pouring paint process, but this process cannot ensure good paint film uniformity, resulting in uneven adhesion. Paint film droplets can clog critical pores and negatively impact the oil mist seal's function. Therefore, it is necessary to develop suitable coating equipment and an effective method for the oil mist seal structure.

[0003] In order to solve the problem of coating the inner wall of the oil mist seal of the main pump motor, the existing coating process method usually adopts the paint filling method. Although it can obtain a coating that meets the coating technical specifications, it brings new problems in many aspects: First, the required paint usually needs to be selected as a single-component paint for painting. If two-component or multi-component paint is used, it is easy to solidify during the paint filling process, which is not conducive to the formation of a paint film with uniform thickness, and it is easy to cause blockage of the voids; second, the paint filling process requires the workpiece to be rotated and the position to be changed, which requires many operating hours and high labor intensity. Otherwise, it needs to be equipped with an electric positioner, which will also increase the cost of coating; third, the procurement cost of single-component paint is relatively high. Therefore, the present invention takes into account the adverse effects of the existing paint filling process and single-component paint, and explores a suitable new coating device and its use method. Summary of the Invention

[0004] The purpose of the present invention is to provide a device and method for coating the inner wall of a narrow and long space in response to the above-mentioned problems, which can eliminate the quality problem of uneven coating thickness caused by the painting process of the oil mist sealing component of the main pump motor, improve the service life of the oil mist sealing component, and maintain the lubricating oil level in the bearing chamber of the main pump motor.

[0005] The technical solution adopted in the present invention is as follows:

[0006] A device for painting the inner walls of narrow and long spaces includes a paint spray gun device with multiple compressed air chambers. The paint spray gun device is connected to a suspendable delivery nested hose group, and the delivery nested hose group is respectively connected to the nozzle of each compressed air chamber; the outlet of the delivery nested hose group is provided with a paint atomization guide component.

[0007] Optionally, the paint spray gun device is provided with an air intake channel and multiple compressed air chambers, the air intake channel is connected to each compressed air chamber, each compressed air chamber is cylindrical, and a joint is provided at one end of each compressed air chamber, and a control rod is connected to the other end through a thread, the outer end of the control rod is provided with a knob, and the control rod can move along the compressed air chamber through the knob and the thread; the inner end of the control rod is provided with a tapered end, and the tapered end acts on the joint.

[0008] Optionally, the delivery nested hose group includes a paint spray hose, the paint atomization guide assembly is arranged at the front end of the paint spray hose, the paint spray hose is outer-circuited with an external hose, a first head is provided between the interior of the external hose and the paint spray hose, and the first head is located at the front end of the external hose; the front periphery of the external hose is also provided with an air jet hole, and the air jet hole is arranged circumferentially around the external hose.

[0009] Optionally, the paint spray hose includes a core hose, and the paint atomization guide assembly includes an annular support member arranged in the core hose, the front side of the annular support member has an inverted slope, the annular support member has a first center member, the front side of the first center member has a conical surface that increases forward, and a paint mist flow gap is provided between the annular support member and the first center member.

[0010] Optionally, the first center piece and the annular support piece are connected by threads, and the threads between the first center piece and the annular support piece have at least two sections separated along the circumferential direction, and there is a gap between each section of the threads, which is the paint mist flow gap.

[0011] Optionally, the first center piece can be moved and adjusted along the axial direction of the core hose.

[0012] Optionally, the paint spray hose includes a core hose and a middle hose nested outside the core hose.

[0013] Optionally, the paint atomization guide assembly includes a second center piece arranged in the core hose, the second center piece has an atomization hole, and the front end of the second center piece has an arc-shaped surface; a second head is also provided in the middle hose, and the rear end of the second head is provided with an arc-shaped surface matching the front end of the second center piece; an adjustment screw is provided in the second head, and a paint mist flow gap is provided between the second head and the adjustment screw.

[0014] A method for coating the inner wall of a narrow and long space, comprising the following steps:

[0015] S1, assembling a nested delivery hose assembly, and connecting multiple starting ends of the nested delivery hose assembly to nozzles of multiple compressed air chambers of a paint spray gun device;

[0016] S2. Install the paint atomization guide assembly at the outlet of the delivery nested hose group;

[0017] S3, one of the compressed air chambers ventilates the outermost hose of the nested delivery hose group, so that the other end of the nested delivery hose group floats;

[0018] S4. The remaining compressed air chambers ventilate the inner hoses of the nested hose group and realize paint spraying through the paint atomization guide assembly at the other end.

[0019] Alternatively, in S4, the delivery nested hose group realizes a siphon effect through the paint atomization guide component, and the paint is sucked out from the small holes of the paint atomization guide component to generate atomization and spray out.

[0020] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0021] 1. The present invention provides a device and method for coating the inner wall of a narrow and long space, which meets the needs of the coating process of the surface of a narrow and long inner cavity, has a wide range of applicability, and can be used to repair coatings on space areas that cannot be reached by conventional coating tools, especially the inner cavity surfaces of large equipment that cannot be disassembled for inspection.

[0022] 2. The present invention provides a device and method for coating the inner wall of a narrow and long space, which can adjust key coating parameters such as inner cavity spaces of different sizes, paints of different components, and different temperatures until they fully meet the coating process requirements.

[0023] 3. The present invention provides a device and method for painting the inner wall of a narrow space, which can ensure that the paint spray nozzle is suspended on the center line of the narrow inner cavity, and the sprayed paint mist can cover the 360° side in front of the nozzle, ensuring the uniformity of the paint film on the surface of each inner cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0025] Figure 2 It is a schematic diagram of the connection between the delivery nested hose group and the paint atomization guide component.

[0026] Figure 3 It is a schematic diagram of the spraying of the device of the present invention in a narrow and long inner cavity.

[0027] Figure 4 It is a schematic diagram of embodiment 1.

[0028] Figure 5 This is a schematic diagram of Example 2.

[0029] Markings in the figure: 1-paint spray gun device, 11-air inlet channel, 12-compressed air chamber, 13-connector, 14-control lever, 15-knob, 16-air valve, 17-spring, 2-delivery nested hose group, 21-paint spray hose, 211-core hose, 212-middle hose, 22-external hose, 221-injection hole, 23-first head, 3-paint atomization guide assembly, 31-annular support, 32-first center piece, 33-second center piece, 34-second head, 35-adjustment screw, 4-narrow inner cavity, 5-paint film. DETAILED DESCRIPTION

[0030] The present invention will be described in detail below with reference to the accompanying drawings.

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] A coating device for the inner wall of a narrow and long space, such as Figure 1-5 As shown, it includes a paint spray gun device 1 with multiple compressed air chambers 12, and the paint spray gun device 1 is connected to a suspendable delivery nested hose group 2, and the delivery nested hose group 2 is respectively connected to the nozzle of each compressed air chamber 12; the outlet of the delivery nested hose group 2 is provided with a paint atomization guide component 3.

[0033] The paint spray gun assembly 1 serves as the control center, utilizing multiple independent compressed air chambers 12 to achieve precise airflow distribution. Some airflow is delivered directly to the end of the hose, suspending the spray head and positioning it. Other airflow propels liquid paint from the paint tank into the delivery hose or assists in paint atomization. The delivery nested hose assembly 2 utilizes a multi-layered, flexible hose structure. The airflow from the outer layer creates an air cushion effect, propels the atomizer assembly to suspend the spray head over the central axis of the inner cavity. The inner layer delivers paint to the end atomizer assembly. The flexible nested hoses extend into deep cavities inaccessible to conventional tools, allowing the spray head to automatically suspend and center, ensuring a uniform paint film thickness. The paint atomization guide assembly 3, comprised of a set of wear-resistant metal components, is mounted on the end face of the delivery nested hose assembly 2. This atomization mechanism shears the paint liquid into a uniform mist, directing it toward the inner cavity wall at a specific angle. This highly efficient atomization mechanism is suitable for high-viscosity two-component paints, reducing reliance on specialized paints. It also avoids the uneven paint film and the risk of paint shedding associated with traditional paint filling processes, ensuring the long-term safe operation of the nuclear power plant's main pumps.

[0034] This solution addresses the difficulty of painting within the existing narrow, long inner cavity. Through rational design, a flexible hose extends the spray nozzle of a conventional spray gun into the narrow inner cavity. An atomizer is installed at the end of the flexible hose, ensuring a uniform atomization effect and forming a uniform coating on the inner cavity surface. Furthermore, the flexible hose is configured as a nested, multi-layer composite tube, with the prepared paint liquid transported internally and compressed air connected to the external starting end. An exhaust hole is provided at the end of the hose, ensuring that the end of the composite tube, along with the atomizer assembly, is suspended on the axis of the narrow, long space under the propulsion of compressed air, ensuring that the paint mist sprayed from the end atomizer assembly travels the same distance to reach the inner cavity surface.

[0035] As another specific embodiment, the paint spray gun device 1 is provided with an air intake channel 11 and a plurality of compressed air chambers 12. The air intake channel 11 is connected to each compressed air chamber 12. Each compressed air chamber 12 is cylindrical, and a joint 13 is provided at one section of each compressed air chamber 12. The other end is connected to a control rod 14 by a thread. The outer end of the control rod 14 is provided with a knob 15. The control rod 14 can move along the compressed air chamber 12 through the knob 15 and the thread; the inner end of the control rod 14 is provided with a tapered end, and the tapered end acts on the joint 13.

[0036] Each compressed air chamber 12 independently controls the airflow of different functions. Each air chamber corresponds to an independent knob 15, which can adjust the on-off and flow of different air paths respectively. When the knob 15 is rotated, the conical tip of the control rod 14 approaches or moves away from the outlet of the joint 13. When the conical tip presses the outlet of the joint 13, the air path is closed, and when the conical tip moves away from the outlet of the joint 13, the air path is opened. The size of the gap determines the compressed air flow rate. By precisely controlling the suspended airflow, it is ensured that the nozzle is always located on the axis of the inner cavity, so that the paint mist evenly covers the inner wall 360°, solving the problem of uneven coating in narrow and long spaces. Furthermore, a trigger is also provided on the paint spray gun device 1, and the trigger is linked to the air inlet channel 11 through the air valve 16. When the trigger is pressed, the air valve opens and the air inlet channel 11 starts to take in air. A spring 17 is provided on the control rod 14 to push the threads to fit tightly together and reduce air leakage between the threads.

[0037] As another specific embodiment, the conveying nested hose group 2 includes a paint spray hose 21, the paint atomization guide assembly 3 is arranged at the front end of the paint spray hose 21, and an external hose 22 is provided on the outer shell of the paint spray hose 21. A first head 23 is provided between the inside of the external hose 22 and the paint spray hose 21, and the first head 23 is located at the front end of the external hose 22; an air jet hole 221 is also provided on the front outer periphery of the external hose 22, and the air jet hole 221 is arranged around the circumference of the external hose 22.

[0038] The paint spray hose 21 serves as the core channel for delivering paint. Its flexible design allows it to penetrate into the narrow and curved path of the cavity. The smooth inner wall reduces paint residue and ensures that the paint liquid is efficiently delivered to the front atomization component. The paint atomization guide component 3 shears the paint liquid into uniform droplets. The external hose 22 forms an annular compressed air channel to deliver the suspended and positioned airflow to the front jet hole 221; at the same time, it physically isolates the paint spray hose 21 to prevent friction damage to the cavity or paint contamination of the air path. The first head 23 seals the annular air path, forcing the compressed air to be ejected only in a directional manner from the jet hole 221; it cooperates with the jet hole 221 to form a high-pressure air cushion base to provide stable suspension thrust. The circumferential jet hole 221 has a multi-hole uniformly distributed design that ejects an annular uniform air curtain, generating a symmetrical reverse thrust to suspend and position the atomization component on the axis of the cavity. The jet hole 221 has multiple fine holes for ejecting compressed air. The air jet holes 221 and the first end cap 23 work together to generate a directional high-pressure air cushion, automatically adjusting the atomizing assembly to the centerline of the cavity, fundamentally preventing uneven thickness of the paint film 5 caused by eccentricity. The first end cap 23 has a central opening and a flanged circumference. The flange of the first end cap 23 is embedded between the paint spray hose 21 and the outer air hose, forming a seal against the outer air hose. Preferably, a hoop is added to the outer surface of the outer hose end to increase the strength of the first end cap 23 and improve its resistance to compressed air impact.

[0039] As another specific embodiment, the paint spray hose 21 includes a core hose 211, and the paint atomization guide assembly 3 includes an annular support 31 disposed within the core hose 211. The front side of the annular support 31 has an inverted bevel. The annular support 31 includes a first center piece 32. The front side of the first center piece 32 has a tapered surface that increases forward. A paint mist flow gap is defined between the annular support 31 and the first center piece 32. The inner surfaces of both ends of the annular support 31 are provided with a certain taper angle to reduce the flow resistance of the paint liquid and the wear of the annular support 31, and to form a spray angle for the paint mist. The inverted bevel on the front side of the annular support 31 cooperates with the tapered surface of the first center piece 32 to form a gradually converging and diverging flow channel, accelerating the shear atomization of the paint liquid. The flow channel is continuous 360° around the axis of the support and the center piece, enabling 360° spraying of the nozzle without dead angles. The paint mist flow gap allows paint particles to pass through. Among them, a paint pot is provided between the input end of the core hose 211 and the compressed air chamber 12. The paint pot has a short inlet and a long outlet. The airflow flows to the paint liquid tank, and then pushes the paint liquid into the core hose 211 to avoid bubbles mixing in and causing the paint film 5 to fail to seal.

[0040] In another specific embodiment, the first center piece 32 and the annular support member 31 are connected by threads. The threads between the first center piece 32 and the annular support member 31 have at least two circumferentially spaced segments, each segment having a gap between them, which represents the paint mist flow gap. The multiple segments of threads provide uniform locking force, ensuring strict coaxiality between the first center piece 32 and the support member, and preventing uneven paint film 5 caused by a skewed atomization gap. The physical gap between the threads creates a pre-mixing chamber for the paint liquid and compressed air, allowing airflow to penetrate the paint liquid flow in advance, improving subsequent atomization efficiency.

[0041] As another specific embodiment, the first centerpiece 32 is adjustable along the axial direction of the core hose 211. By axially moving the first centerpiece 32, the gap between its tapered surface and the inverted bevel of the support member can be precisely adjusted. For high-viscosity paints, a smaller gap enhances shear force, while for low-viscosity paints, a larger gap prevents dry spray defects caused by excessive atomization. The first centerpiece 32 has a slotted groove, which allows for axial adjustment of the assembly without the need for removal of the device.

[0042] In another specific embodiment, the paint spray hose 21 includes a core hose 211 and a middle hose 212 nested outside the core hose 211. Unlike the previous embodiment, the middle hose 212 in this embodiment creates a secondary gas-liquid isolation layer between the core hose 211 and the outer hose 22, forming an annular paint buffer channel with the core hose 211, reducing the resistance to transporting high-viscosity paint.

[0043] As another specific embodiment, the paint atomization guide assembly 3 includes a second center piece 33 arranged in the core hose 211, the second center piece 33 has an atomization hole, and the front end of the second center piece 33 has an arc surface; the middle hose 212 is also provided with a second head 34, and the rear end of the second head 34 is provided with an arc surface matching the front end of the second center piece 33; the second head 34 has an adjustment screw 35, and there is a paint mist flow gap between the second head 34 and the adjustment screw 35. The second centerpiece 33 is designed for high-viscosity two-component coatings. Its small aperture shear force forces initial atomization of the paint liquid. The rear curved surface precisely matches the curved surface of the second centerpiece 33, forming a tapered airflow gap. The adjustment screw 35, similar to the first centerpiece 32, features symmetrical external threads that engage the intermittent internal threads of the second end cap 34, allowing for clearance adjustment by screwing in and out. The conical guide and the inner conical surface of the second end cap 34 form an annular atomization gap, shearing the paint liquid into micron-sized particles. Compressed air is ejected at high speed through the gap between the second end cap 34 and the adjustment screw 35, drawing in the paint liquid flowing out of the atomization hole. The second end cap 34 and the adjustment screw 35 are also connected by a threaded connection. The threads between the second end cap 34 and the adjustment screw 35 have at least two circumferentially separated segments, each separated by a gap that represents the paint mist flow gap. The adjustment screw 35 is adjustable and movable along the axial direction of the core hose 211.

[0044] A method for coating the inner wall of a narrow and long space, comprising the following steps:

[0045] S1, connecting the multiple starting ends of the delivery nested hose group 2 to the nozzles of the multiple compressed air chambers 12 of the paint spray gun device 1 respectively;

[0046] S2, installing the paint atomization guide assembly 3 at the outlet of the delivery nested hose assembly 2;

[0047] S3, one of the compressed air chambers 12 ventilates the outermost hose of the nested transport hose group 2, so that the other end of the nested transport hose group 2 floats;

[0048] S4. The remaining compressed air chambers 12 ventilate the inner hoses of the nested conveying hose group 2 and realize paint spraying through the paint atomization guide assembly 3 at the other end.

[0049] A controlled airflow is injected into the outermost hose via a dedicated compressed air chamber 12, creating a directional jet at the end of the nested hose. This creates reverse thrust, keeping the nozzle assembly stably suspended at the center of the inner axis. Independent compressed air chambers 12 control different functional airflows, enabling precise adjustment of key parameters. Multiple airflow paths prevent interference, significantly reducing reliance on single-component paints and enabling the use of stronger, two-component paints to extend equipment life. The nozzle is suspended by airflow, ensuring no risk of scratching the inner wall during retraction, protecting the integrity of the finished paint film. Precise adjustment of nozzle position before application avoids paint waste from repeated test sprays.

[0050] As another specific embodiment, in S4, the nested delivery hose assembly 2 creates a siphon effect through the paint atomization guide assembly 3, drawing paint from the small holes in the paint atomization guide assembly 3, atomizing and spraying the paint. When the trigger is pulled, compressed air from the middle hose is ejected at high speed through the conical gap between the adjustment screw 35 and the second end cap 34, creating a local vacuum at the atomization orifice outlet of the second centerpiece 33. A significant pressure differential between the normal pressure of the paint tank and the negative pressure zone of the atomization orifice creates a pressure differential, forcing the paint liquid to move from the core hose 211 to the atomization orifice, achieving self-priming delivery without the need for a mechanical pump.

[0051] Example 1

[0052] For low viscosity, one-component paints or paints that are easy to dilute:

[0053] Step 1:

[0054] Step 1.1, pass the core hose 211 with an inner diameter of Ø5 and an outer diameter of Ø6 through the outer hose 22 with an inner diameter of Ø6 and an outer diameter of Ø8 to form a composite hose of nested sizes;

[0055] Step 1.2: Connect the starting ends of the core hose 211 and the outer hose 22 to the nozzles of the two compressed air chambers 12 of the paint spray gun device 1 respectively.

[0056] Step 2:

[0057] Step 2.1: The annular support member 31 has an M5.2 thread on its outer circumference and an M3.6 internal thread on its inner circumference. The annular support member 31 is installed on the end face of the core hose 211, and the threads on the outer circumference of the annular support member 31 are connected to the inner circumference of the core hose 211.

[0058] Step 2.2: Install the first center piece 32 onto the internal threads of the annular support member 31. The external threads of the first center piece 32 form a tight fit with the internal threads of the annular support member 31. A straight groove is provided on the end surface of the first center piece 32 to adjust the relative relationship between the first center piece 32 and the annular support member 31, particularly the gap formed therebetween. Optionally, the external threads of the first center piece 32 are not continuous along the circumference, but rather comprise four intermittent segments symmetrically arranged around the axis of the first center piece 32.

[0059] Step 3

[0060] Step 3.1: Place the outlet end of the delivery nested hose assembly 2 into the narrow inner cavity 4 through the reserved screw hole of the narrow inner cavity 4, and simultaneously place the endoscope into the narrow inner cavity 4;

[0061] Step 3.2: Push the endoscope to the position where the paint atomization guide assembly 3 is located to facilitate observation of the paint atomization guide assembly 3;

[0062] Step 3.3: Introduce compressed air into the pipeline of the external hose 22 and adjust the air flow of the compressed air to adjust the position of the paint atomizing guide component 3 in the narrow inner cavity 4;

[0063] Step 3.4: When the position of the paint atomization guide component 3 is adjusted to the axis of the narrow inner cavity, fix the air flow rate and slowly withdraw the endoscope.

[0064] Step 4

[0065] Step 4.1: Open the compressed air in the core hose 211 through the paint spray gun device 1. The airflow goes to the paint pot, pushing the paint liquid into the core hose 211 and forming a large pressure near the atomizing assembly at the end, so that the paint liquid is atomized and sprayed out to form a uniform paint film 5;

[0066] Step 4.2: Slowly withdraw the pipeline, and the paint mist follows the paint atomization guide component 3 and is continuously sprayed on the surface of the inner cavity through which it passes, forming a uniform paint film 5 until the pipeline is completely withdrawn from the inner cavity.

[0067] Example 2

[0068] For high viscosity, two-component or multi-component paints or paints that are difficult to dilute:

[0069] In order to adapt to high-viscosity two-component paints or multi-component paints, reduce the use of organic solvents and improve the environmental protection effect of coating construction, the coating device in the present invention needs to add an intermediate layer sleeve in the middle of the core hose 211 and the outer layer hose, and install a paint atomization guide component 3 with a siphon effect at the end of the core sleeve.

[0070] Step 1

[0071] 1.1. Pass the core hose 211 with an inner diameter of Ø5 and an outer diameter of Ø6 through the middle hose 212 with an inner diameter of Ø6 and an outer diameter of Ø8, and then pass the double-layer sleeve through the outer hose 22 with an inner diameter of Ø8 and an outer diameter of Ø10, forming a nested hose containing three types of hoses;

[0072] 1.2. Connect the starting ends of the core hose 211, the middle hose 212, and the outer hose 22 to the nozzles of the three compressed air chambers 12 of the paint spray gun device 1 respectively;

[0073] Step 2

[0074] 2.1. Install the second center piece 33 on the end face of the core hose 211. A small hole of Ø1.2 is provided in the center of the second center piece 33, and waist-shaped small holes are evenly arranged around the small hole.

[0075] 2.2. The outer surface of the core hose 211 is installed in the middle hose;

[0076] 2.3. Install the second end cap 34 inside the middle hose. The middle of the second end cap 34 is provided with a tapered hole.

[0077] 2.4. Install the adjusting screw 35 on the tapered hole. The tapered surface is provided with symmetrically distributed intermittent threads.

[0078] 2.5. Install the first sealing head 23 in the outer hose. A circular light hole is provided in the middle of the first sealing head 23.

[0079] Step 3

[0080] Step 3.1: Place the outlet end of the delivery nested hose assembly 2 into the narrow inner cavity 4 through the reserved screw hole of the narrow inner cavity 4, and simultaneously place the endoscope into the narrow inner cavity 4;

[0081] Step 3.2: Push the endoscope to the position where the paint atomization guide assembly 3 is located to facilitate observation of the paint atomization guide assembly 3;

[0082] Step 3.3: Introduce compressed air into the pipeline of the external hose 22 and adjust the air flow of the compressed air to adjust the position of the paint atomizing guide component 3 in the narrow inner cavity 4;

[0083] Step 3.4: When the position of the paint atomization guide component 3 is adjusted to the axis of the narrow inner cavity, fix the air flow rate and slowly withdraw the endoscope.

[0084] Step 4

[0085] Step 4.1: Use a paint spray gun to open the compressed air in the middle layer hose, creating a siphon effect near the second center piece 33 of the core hose 211. The paint is sucked out of the hole to produce atomization, and then sprayed out from the paint mist flow gap in the center hole of the second end cap 34 on the middle hose, forming a uniform paint film 5.

[0086] Step 4.2: Slowly withdraw the pipeline, and the paint mist follows the paint atomization guide component 3 and is continuously sprayed on the surface of the inner cavity through which it passes, forming a uniform paint film 5 until the pipeline is completely withdrawn from the inner cavity.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The present invention extends to any new features or any new combinations disclosed in this specification, and any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the detailed technical features not disclosed in this embodiment, such as the specific structure, are all prior art, and those skilled in the art can obtain them from the prior art; the connection method can be a fixed connection, a detachable connection, or an integrated connection; it can be a fixed connection, a movable connection or a hinged connection, and can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific manner of the above terms in the embodiments of the present invention can be understood according to the specific circumstances, and the embodiments disclosed herein do not make specific limitations on this.

Claims

1. A coating device for the inner wall of a narrow and long space, characterized by: The invention comprises a paint spray gun device (1) with a plurality of compressed air chambers (12), wherein the paint spray gun device (1) is connected to a suspendable delivery nested hose group (2), wherein the delivery nested hose group (2) is respectively connected to the nozzle of each compressed air chamber (12); and a paint atomization guide assembly (3) is provided at the outlet of the delivery nested hose group (2); The delivery nested hose group (2) comprises a paint spray hose (21), the paint atomization guide assembly (3) is arranged at the front end of the paint spray hose (21), an outer hose (22) is provided on the outer shell of the paint spray hose (21), a first seal (23) is provided between the interior of the outer hose (22) and the paint spray hose (21), and the first seal (23) is located at the front end of the outer hose (22); an air injection hole (221) is further provided on the outer periphery of the front portion of the outer hose (22), and the air injection hole (221) is arranged around the circumference of the outer hose (22); The paint spray hose (21) comprises a core hose (211) and a middle hose (212) nested outside the core hose (211); The paint atomization guide assembly (3) includes a second center piece (33) arranged in a core hose (211), the second center piece (33) has an atomization hole, and the front end of the second center piece (33) has an arc surface; a second head (34) is also provided in the middle hose (212), and the rear end of the second head (34) is provided with an arc surface matching the front end of the second center piece (33); an adjustment screw (35) is provided in the second head (34), and a paint mist flow gap is provided between the second head (34) and the adjustment screw (35).

2. The coating device for the inner wall of a narrow and long space according to claim 1, characterized in that: The paint spray gun device (1) is provided with an air inlet channel (11) and a plurality of compressed air chambers (12). The air inlet channel (11) is connected to each compressed air chamber (12). Each compressed air chamber (12) is cylindrical, and one end of each compressed air chamber (12) is provided with a joint (13), and the other end is connected to a control rod (14) through a thread. The outer end of the control rod (14) is provided with a knob (15), and the control rod (14) can move along the compressed air chamber (12) through the knob (15) and the thread; the inner end of the control rod (14) is provided with a tapered end, and the tapered end acts on the joint (13).

3. A method for coating the inner wall of a narrow and long space, characterized by: Using the device according to any one of claims 1-2, comprising the following steps: S1, assembling the delivery nested hose group (2), and connecting the multiple starting ends of the delivery nested hose group (2) to the nozzles of the multiple compressed air chambers (12) of the paint spray gun device (1); S2, installing the paint atomizing guide assembly (3) at the outlet of the delivery nested hose assembly (2); S3, one of the compressed air chambers (12) ventilates the outermost hose of the transport nested hose group (2), so that the other end of the transport nested hose group (2) floats; S4, the remaining compressed air chamber (12) ventilates the inner layer hose of the delivery nested hose group (2), and realizes paint spraying through the paint atomization guide component (3) at the other end.

4. The method for coating the inner wall of a narrow and long space according to claim 3, characterized in that: In S4, the delivery nested hose group (2) realizes a siphon effect through the paint atomization guide component (3), and the paint is sucked out from the small holes of the paint atomization guide component (3) to generate atomization and spray out.

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