Spin-spray device for one-time spray-up forming of long polyurethane pipes and method of use thereof

Abstract

The application relates to the technical field of long-distance pipeline processing, and particularly discloses a rotary spraying device for one-time spray construction forming of a long-distance polyurethane pipe and a use method thereof. The rotary spraying device comprises a rotary cup, a flange sheet and a rotary sheet. The rotary cup is integrally arranged in a circular conical frustum body, is horizontally arranged during spray construction, is open at one end of the bottom of the conical frustum body, and is provided with the flange sheet. The flange sheet is fixed with the rotary sheet, and the rotary sheet is driven by a pneumatic motor. A feeding pipe is arranged on the rotary sheet, the rotary cup is hollow, and one end of the top of the conical frustum body is sealed. A plurality of spray holes are arranged on the side of the conical frustum body of the rotary cup. The spray holes are divided into first spray holes, second spray holes and third spray holes. The first spray holes are arranged close to one end of the flange sheet, the third spray holes are arranged away from the other end of the flange sheet, and the second spray holes are arranged in a V-shaped mode on the side of the conical frustum body. In the use method, the rotary spraying device is used for spray construction.

Description

Technical Field

[0001] This invention relates to the field of long-distance pipeline processing technology, specifically to a rotary spraying device for one-time spraying and forming of long-distance polyurethane pipes and its application method. Background Technology

[0002] Regarding pipeline processing technology, there are some similar technical solutions as follows: A spraying device for pipeline repair and its usage method are disclosed in CN201911297627; A multi-layer spraying rotary cup for inner wall of a pipe is disclosed in CN 205761980 U, in which the coating material in the rotary cup is mixed and dispersed multiple times and then sprayed outward in a mist.

[0003] The disadvantages of the above technology:

[0004] 1. In the patent "Spraying Device for Pipeline Repair and its Usage Method", the top of the rotary cup is not capped. When the paint flow rate is high, incompletely atomized paint will be sprayed through the top of the rotary cup into the original pipeline or the newly sprayed pipeline, affecting the wall quality of the newly sprayed polyurethane pipeline in the original pipeline. Furthermore, the top horizontal height is lower than the tail horizontal height, which increases the flow velocity of the paint. When the paint flow rate is large and the rotary cup orifice cannot completely spray all the paint at one time, incompletely atomized paint will be sprayed through the top of the rotary cup into the original pipeline or the newly sprayed pipeline, which will also affect the wall quality of the newly sprayed polyurethane pipeline in the original pipeline.

[0005] 2. In the patent "Spraying device for pipeline repair and its usage method", since the main spraying position of the coating is set in the middle section of the rotary cup, when the rotary cup rotates at high speed (20,000 rpm), the rotational eccentricity caused by the unavoidable incomplete asymmetry during manufacturing and installation will cause greater vibration in the middle section than in the tail section, resulting in uneven wall thickness of the newly sprayed pipeline.

[0006] 3. The patent "A Multi-Layer Spraying Rotary Cup for Inner Wall of a Pipe" places the spray holes of each rotary cup at the front or rear end of each rotary cup. This arrangement will cause the paint to stick to the wall and accumulate in the areas without spray holes when the paint flow rate and viscosity are high, eventually spreading to the spray holes and preventing the paint from being sprayed out.

[0007] 4. The patent "A Multi-Layer Spray Coating Rotary Cup for Pipe Inner Wall" has a multi-layer structure of 2-5 coaxial rotary cups. The unavoidable asymmetry of each rotary cup during manufacturing and installation will cause the multi-layer rotary cup to generate greater rotational eccentricity and overall vibration than the single-layer rotary cup under high-speed (20,000 rpm) rotation, resulting in uneven pipe wall thickness of the newly sprayed pipe.

[0008] Polyurethane spraying for pipeline renewal is a technological solution for the one-time, complete renewal of long-distance pipelines. Currently available rotary spraying equipment cannot meet the requirements for spraying high-flow-rate, high-viscosity coatings. The technical problem this invention aims to solve is as follows:

[0009] 1. To prevent high-flow, high-viscosity paint from rushing out of the top of the rotary cup before it is atomized and sprayed out, thus affecting the quality of the newly sprayed pipe wall;

[0010] 2. Ensure that high-flow, high-viscosity coatings are atomized and sprayed out by the high-speed rotating cup during the spraying process to prevent material accumulation inside the cup from affecting the spraying process and quality.

[0011] 3. During the high-speed rotation of the rotary cup in the spraying process, the rotational eccentricity and vibration caused by the unavoidable asymmetry of the rotary cup during manufacturing and installation are minimized, so that the wall thickness of the newly sprayed pipe is uniform. Summary of the Invention

[0012] The purpose of this invention is to provide a rotary spraying device for one-time spraying and forming of long-distance polyurethane pipes and its usage method, so as to solve the problems mentioned in the background art.

[0013] To achieve the above objectives, the present invention provides the following technical solution: a rotary spraying device for one-time spraying of long-distance polyurethane pipes, comprising a rotary cup, a flange, and a rotating plate. The rotary cup is configured as a circular truncated cone, and is horizontally positioned during spraying. One end of the bottom of the truncated cone of the rotary cup is open and fitted with a flange. The flange and the rotating plate are fixed to each other, and the rotating plate is driven by a pneumatic motor. A feed pipe is provided on the rotating plate. The rotary cup is hollow inside, and one end of the top of its truncated cone is sealed. Several types of spray holes are provided on the side of the truncated cone of the rotary cup. The spray holes are divided into a first spray hole, a second spray hole, and a third spray hole. The first spray hole is located near one end of the flange, the third spray hole is located away from the flange, and the second spray holes are arranged in a V-shape on the side of the truncated cone.

[0014] Preferably, the overall thickness of the rotating cup is uniform, set to 1.2-1.4 mm, and the top diameter of the truncated cone of the rotating cup is 18-22 mm, the tail diameter is 29-33 mm, and the height is 30-34 mm.

[0015] Preferably, the first injection holes are evenly distributed around the side of the truncated cone, and there are two rows in total; wherein the diameter of the first injection hole in the first row is 1.9 to 2.1 mm, the hole edge is close to the edge of the flange, and there are a total of 24 holes; the center distance between the first injection hole in the second row and the first injection hole in the first row is 3.7 to 3.9 mm, the diameter is 1.7 to 1.9 mm, and there are a total of 24 holes.

[0016] Preferably, there are four sets of the second spray holes, and the included angle of the V-shape formed by each set is 60°; the diameter of the second spray hole is 1.7 to 1.9 mm, the center distance between adjacent second spray holes is 2.7 to 2.9 mm, and the center distance between the outermost second spray hole and the nearest first spray hole is 2.8 to 3.2 mm.

[0017] Preferably, the diameter of the third injection hole is 1.4 to 1.6 mm, and the third injection holes are evenly distributed around the side of the truncated cone; wherein three vertically arranged third injection holes are spaced apart from a single third injection hole, and a total of four sets are arranged, and the center distance between adjacent holes in a vertical set of third injection holes is 2.1 to 2.3 mm.

[0018] Preferably, the central axis of the feed pipe coincides with the central axis of the rotating plate, and fixing holes are provided on both the flange and the rotating plate. The fixing holes of the two are aligned with each other and fixed by bolts.

[0019] This invention also provides a method for using a rotary spraying device for one-time spraying of long-distance polyurethane pipes, comprising the following steps:

[0020] S1. Secure the flange and the rotating plate together with bolts and place them horizontally at one end of a long-distance old pipeline.

[0021] S2. Add polyurethane coating into the rotary cup through the feed pipe and turn on the pneumatic motor to drive the rotary cup to rotate. The polyurethane coating is sprayed out from the spray hole at high speed. The atomized polyurethane coating is sprayed onto the inner wall of the old pipe to form a new polyurethane pipe wall.

[0022] S3. While spraying the rotary cup, drag the rotary spraying device along the longitudinal axis of the pipe towards the direction of the rotating plate, spraying while dragging, until the other end of the old pipe, so that a new polyurethane pipe is sprayed into shape in the long old pipe.

[0023] S4. After the spraying is completed, remove the rotary spraying device.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] 1. This invention uses a method of sealing the top of the rotary cup to prevent the phenomenon of unatomized coating flowing out of the top of the rotary cup due to excessive flow, thus affecting the quality of the new pipe wall;

[0026] 2. In this invention, the rotary cup is set as a single layer and the high-flow, high-viscosity paint spraying section is set at the tail end of the rotary cup closest to the pneumatic motor. This can minimize the rotational eccentricity and overall vibration of the rotary cup caused by the unavoidable asymmetry of the rotary cup during manufacturing and installation at high speed (20,000 rpm), resulting in a uniform wall thickness of the newly sprayed pipe.

[0027] 3. This invention adopts a frustum-shaped rotary cup with a higher front and lower rear in the horizontal direction, and sets V-shaped and annular spray holes at the front end of the rotary cup. This increases the obstruction of the paint entering the front end of the rotary cup, and also allows excess paint to be atomized and sprayed out even when the paint flow rate is too large. This avoids the accumulation of paint inside the rotary cup and ensures the smooth flow of the rotary cup spray nozzle. This makes it possible to use the polyurethane spraying method to spray new pipelines and replace existing pipelines in long-distance old pipelines for a long time. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the present invention;

[0029] Figure 2 This is the front view of the present invention;

[0030] Figure 3 This is a right view of the present invention;

[0031] Labels in the diagram: 1. Rotary cup; 2. First injection hole; 3. Second injection hole; 4. Third injection hole; 5. Flange; 6. Rotating plate; 7. Feed pipe; 8. Fixing hole. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be noted that the terms "vertical," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0034] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] Please see Figure 1-3 The following describes any embodiment of the present invention for further explanation:

[0036] A rotary spraying device for one-time spraying of long-distance polyurethane pipes includes a rotary cup 1, a flange 5, and a rotating blade 6. The rotary cup 1 is integrally shaped as a circular truncated cone. During spraying, the rotary cup 1 is horizontally positioned. The flange 5, with four fixing holes 8 at the tail end of the truncated cone, is 6mm thick and is bolted to the rotating blade 6 driven by a pneumatic motor through the fixing holes 8. The top of the truncated cone is a 1.3mm thick flat cap. The top diameter of the rotary cup 1 is 20mm, the tail diameter is 31mm, and the height is 32mm. The wall thickness of the rotary cup 1 is 1.3mm. By sealing the top of the rotary cup 1, the phenomenon of un-atomized paint overflowing from the top of the rotary cup 1 due to excessive flow, thus affecting the quality of the newly sprayed pipe wall, is prevented. The use of a truncated cone-shaped rotary cup with a higher front and lower rear in the horizontal direction increases the obstruction of the paint entering the front end of the rotary cup 1, so that the paint is sprayed out from the two rows of spray holes at the bottom of the cone as much as possible. This can avoid the rotational eccentricity and overall vibration caused by the unavoidable asymmetry of the rotary cup 1 during manufacturing and installation at high speed (20,000 rpm) during the spraying process, so that the wall thickness of the newly sprayed pipe is uniform.

[0037] Several types of spray holes are provided on the side of the cone-shaped body of the rotary cup 1. The spray holes are divided into a first spray hole 2, a second spray hole 3, and a third spray hole 4. The first spray hole 2 is set at one end of the flange 5, the third spray hole 4 is set at the end away from the flange 5, and the second spray hole 3 is arranged in a V-shape on the side of the cone-shaped body.

[0038] The first spray holes 2 are evenly distributed around the side of the truncated cone, with two rows in total. The first row of spray holes has a diameter of 2mm and its edges are close to the edge of the flange. The center distance between adjacent spray holes is 4mm, with a total of 24 holes. The center distance between the second row of spray holes and the first row of spray holes is 3.8mm, and the diameter is 1.8mm, with a total of 24 holes. These two rows of spray holes serve as the main spraying section for spraying high-flow-rate, high-viscosity coatings from the rotary cup 1. They are located at the tail end of the rotary cup 1, which is closest to the pneumatic motor. This arrangement minimizes the rotational eccentricity and overall vibration caused by the unavoidable asymmetry of the rotary cup 1 during manufacturing and installation at high speed (20,000 rpm) during spraying, resulting in a uniform wall thickness of the newly sprayed pipe.

[0039] Four sets of second spray holes 3, arranged in a V-shape at a 60° angle, are positioned 3mm from the second row of spray holes at the tail of the cone and pointing towards the top of the cone. The diameter of each second spray hole 3 is 1.8mm, and the center-to-center distance between adjacent spray holes is 2.8mm. Four sets of single and three vertically aligned third spray holes 4 are evenly arranged at the top of the cone. All three sets have a diameter of 1.5mm, and the center-to-center distance between adjacent vertically aligned third spray holes 4 is 2.25mm. These spray holes ensure that even with excessive paint flow, excess paint can still be atomized and sprayed out, preventing paint accumulation inside the rotary cup 1 and ensuring unobstructed flow at the spray nozzle of the rotary cup 1.

[0040] To ensure the stability of the rotary cup 1 under high-speed rotation, the rotary cup 1 is a single-layer structure. All parts of the rotary cup 1, such as the flange 5, the cap, and the cup wall, are integrally processed from aluminum alloy or stainless steel. This minimizes the rotational eccentricity and overall vibration caused by the unavoidable asymmetry of multi-layer rotary cup devices during manufacturing and installation at high speed (20,000 rpm), resulting in uniform wall thickness of the newly sprayed pipe.

[0041] The above are the dimensions and styles of the rotary spraying device for spraying new polyurethane pipes with diameters of DN150-DN500. For spraying new pipes with diameters of DN500 and larger wall thicknesses, while enlarging the external dimensions of the rotary cup proportionally, the spray holes at the tail of the rotary cup cone and the V-shaped arrangement of the spray holes can be added to more layers to increase the flow rate of the sprayed coating.

[0042] The method for using a rotary spraying device for one-time spraying of long-distance polyurethane pipes includes the following steps:

[0043] S1. Secure the flange 5 and the rotating plate 6 to each other with bolts, and place them together horizontally at one end of a long-distance old pipeline;

[0044] S2. Add polyurethane coating into rotary cup 1 through feed pipe 7, and turn on pneumatic motor to drive rotary cup 1 to rotate. The polyurethane coating is sprayed out from the spray hole at high speed. The atomized polyurethane coating is sprayed onto the inner wall of the old pipe to form a new polyurethane pipe wall.

[0045] S3. While spraying the rotary cup 1, drag the rotary spraying device along the longitudinal axis of the pipe towards the rotating plate 6, spraying while dragging, until the other end of the old pipe, so that a new polyurethane pipe is sprayed into shape in the long old pipe.

[0046] S4. After the spraying is completed, remove the rotary spraying device.

[0047] This method was applied in the test of replacing a DN300*190m water supply pipeline using polyurethane spraying. A two-component high-viscosity polyurethane coating (20000CP) was used at a flow rate of 8L / min. The results, obtained from testing at two points every 6 meters, are as follows: no un-atomized coating was observed throughout the replaced pipeline; the polyurethane pipeline wall thickness was uniform throughout the replacement process, and the error met quality requirements; throughout the entire spraying process, the rotary cup 1 rotated at high speed and operated normally, with no coating accumulation in the rotary cup 1 at the end of the test.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A spin-spray device for one-off spray-up forming of long lengths of polyurethane pipe, characterised in that: The application relates to a spraying cup (1), a flange piece (5) and a rotating piece (6), the spraying cup (1) is integrally arranged as a circular frustum body, is horizontally arranged during spraying construction, is open at one end of the bottom of the frustum body of the spraying cup (1) and is provided with the flange piece (5), the flange piece (5) is fixed with the rotating piece (6), the rotating piece (6) is driven by a pneumatic motor, a feeding pipe (7) is arranged on the rotating piece (6), the spraying cup (1) is internally hollow, one end of the top of the frustum body is sealingly arranged, a plurality of spraying holes are arranged on the side of the frustum body of the spraying cup (1), the spraying holes are divided into first spraying holes (2), second spraying holes (3) and third spraying holes (4), the first spraying holes (2) are arranged close to one end of the flange piece (5), the third spraying holes (4) are arranged away from one end of the flange piece (5), and the second spraying holes (3) are arranged in a V-shaped mode on the side of the frustum body. The first spraying holes (2) are uniformly distributed around the side of the frustum body and are provided with two rows, the first spraying holes (2) in the first row have a diameter of 1.9-2.1 mm, the hole edges are close to the edges of the flange piece (5), and a total of 24 holes are arranged, the center distance between the first spraying holes (2) in the second row and the first spraying holes (2) in the first row is 3.7-3.9 mm, the diameter is 1.7-1.9 mm, and a total of 24 holes are arranged. The second spraying holes (3) are provided with four groups, the included angle of the V-shaped mode formed by each group is 60 DEG, the diameter of the second spraying holes (3) is 1.7-1.9 mm, the center distance between adjacent second spraying holes (3) is 2.7-2.9 mm, and the center distance between the second spraying hole (3) farthest away and the nearest first spraying hole (2) is 2.8-3.2 mm. The diameter of the third spraying holes (4) is 1.4-1.6 mm, the third spraying holes (4) are uniformly distributed around the side of the frustum body, three vertically-arranged third spraying holes (4) are arranged at intervals with single third spraying holes (4), a total of four groups are arranged, and the center distance between adjacent holes of a vertical group of third spraying holes (4) is 2.1-2.3 mm. The central axis of the feeding pipe (7) coincides with the central axis of the rotating piece (6), fixing holes (8) are arranged on the flange piece (5) and the rotating piece (6), the fixing holes (8) of the two are aligned with each other and are fixed through bolts.

2. The spin-spray device for one-time use to build long distance polyurethane pipe by spray-up according to claim 1, characterized in that: The thickness of the spraying cup (1) is uniform and is 1.2-1.4 mm, the diameter of the top of the frustum of the spraying cup (1) is 18-22 mm, the diameter of the tail is 29-33 mm, and the height is 30-34 mm.

3. The method of using the spin-spray device for one-time use to form a long length polyurethane tube by spray-up molding according to any one of claims 1 to 2, characterized in that: The application further discloses a spraying method of the spraying cup. S1, the flange piece (5) and the rotating piece (6) are fixed with each other through bolts and are horizontally arranged at one end in a long-distance old pipeline; S2, polyurethane paint is added into the spraying cup (1) through the feeding pipe (7), a pneumatic motor is started to drive the spraying cup (1) to rotate, the polyurethane paint is sprayed out from the spraying holes under high speed, the atomized polyurethane paint is sprayed on the inner wall of the old pipeline to form a new polyurethane pipeline wall. S3, while the cup (1) spray built, along the longitudinal axis of the pipeline to the direction of the rotating piece (6) drag rotary spray device, drag side spray, until the other end of the old pipeline, so that in the long distance old pipeline is sprayed into a new polyurethane pipe built into shape; S4, after the completion of the spray built, the rotary spray device is removed.

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