A plastic coating device applied to the inner wall of a metal pipe

Abstract

The utility model provides a kind of plastic coating device applied to metal tubular product inner wall, it is specifically related to tubular product inner wall plastic coating technical field.The device includes pit, PLC controller and device ontology;The device ontology includes the base of immediate pit rear side ground installation;The base top is close to pit one side and is provided with mounting stand;The mounting stand is rotationally provided with carousel away from the side of base;The carousel is close to pit one side and is fixed with connecting disc;The pit is provided with bunker box;The top of bunker box is provided with fixed platform;The rear end of fixed platform is fixed with the front end bottom of connecting disc;Bunker box is rotated 360 ° clockwise or counterclockwise with carousel by connecting disc.Compared with traditional plastic coating equipment, the utility model is lower for metal tubular product inner surface cleanliness requirement, convenient recovery plastic coating material, plastic coating effect is uniform and can be applied to multiple size, multiple shape tubular product plastic coating process.

Description

Technical Field

[0001] This utility model patent relates to the field of plastic coating technology for the inner wall of pipes, specifically to a plastic coating device applied to the inner wall of metal pipes. Background Technology

[0002] The coating processes performed using traditional metal pipe inner wall coating equipment are mostly of the following four types, each with its own drawbacks: Process 1, manual spraying: relies on operator experience, resulting in uneven coating thickness and a tendency for drips or missed areas; Process 2, electrostatic adsorption: requires high cleanliness of the pipe inner wall, and incomplete pretreatment can lead to poor coating adhesion; Process 3, dip coating: low powder utilization (only 30%-50%), and many limitations on the shape and size of the pipe fittings; Process 4, curing process: traditional hot air curing is energy-intensive and prone to coating embrittlement due to temperature fluctuations. In addition, existing inner wall powder spraying devices also suffer from uneven coating due to pipe rotation eccentricity and difficulties in recovering excess powder.

[0003] Therefore, there is an urgent need for a high-efficiency, energy-saving pipe inner wall coating equipment that can adapt to various pipe diameters and shapes. Utility Model Content

[0004] To overcome the shortcomings of the prior art, this utility model provides a plastic coating device for the inner wall of metal pipes, the specific technical solution of which is as follows:

[0005] A plastic coating device for the inner wall of metal pipes includes a pit, a PLC controller, and a device body. The device body includes a base installed close to the ground behind the pit. A mounting frame is provided on the top of the base near the pit. A turntable is rotatably mounted on the side of the mounting frame away from the base. A connecting plate is fixed on the side of the turntable near the pit. A hopper is provided inside the pit. A fixed platform is provided on the top of the hopper. The rear end of the fixed platform is fixed to the bottom of the front end of the connecting plate. The hopper rotates 360° clockwise or counterclockwise along with the turntable via the connecting plate.

[0006] Preferably, a servo motor is mounted on the top of the base, and the output shaft of the servo motor is connected to the central shaft of the turntable through a reducer.

[0007] Preferably, the fixed platform has a pipe fixing port in the middle; the hopper box has a hopper opening corresponding to the pipe fixing port, and a hopper door is provided at the hopper opening, the hopper door being controlled to open and close by a cylinder or hydraulic cylinder.

[0008] Preferably, at least two independently controlled hydraulic clamps are provided at equal intervals around the pipe fixing opening on the top of the fixing platform.

[0009] Preferably, the servo motor, cylinder, or hydraulic cylinder is electrically connected to the PLC controller.

[0010] Preferably, the connecting plate includes a support frame and an arc-shaped tube frame installed on the edge of the support frame; a counterweight fixing plate is provided on the top of the side of the support frame away from the fixed platform.

[0011] Preferably, a ladder is provided on the left or right side of the mounting frame.

[0012] Preferably, the plastic coating material inside the hopper is one of linear low-density polyethylene powder, high-density polyethylene, polypropylene, or polytetrafluoroethylene.

[0013] More preferably, the device further includes several sealing plates that match the diameter of the metal pipe flange, several pipe fixing port adjustment plates, and several C-clamps.

[0014] The beneficial effects of this utility model are:

[0015] 1. The cleanliness requirements for the inner surface of metal pipes in this invention are lower than those for general coatings; a cleanliness level of Sa2.0 or higher is sufficient.

[0016] 3. This utility model provides uniform coating and avoids problems such as sagging or missed coating;

[0017] 4. This utility model facilitates the recycling of residual coating materials, effectively improving the reuse rate of plastic powder;

[0018] 5. This utility model can be applied to the plastic coating requirements of the inner walls of metal pipes of various shapes and sizes;

[0019] 6. This invention eliminates the need for repeated heating, effectively preventing coating embrittlement caused by temperature fluctuations. Attached Figure Description

[0020] The accompanying drawings constituting this utility model are provided to further understand this application and do not constitute an undue limitation on this application.

[0021] Figure 1 This is a front sectional view of the present invention;

[0022] Figure 2 This is a side sectional view of the present invention;

[0023] Figure 3 This is a top sectional view of the present invention.

[0024] In the diagram, 1-pit; 2-base; 3-servo motor; 4-reducer; 5-turntable; 6-arc-shaped pipe rack; 7-material bin; 701-fixed platform; 7011-pipe fixing port; 8-hydraulic clamp; 9-installation stand; 10-support frame; 1001-counterweight fixing plate; 11-ladder. Detailed Implementation

[0025] The specific implementation of a plastic coating device for the inner wall of metal pipes provided by this utility model will be further described in conjunction with the accompanying drawings and embodiments.

[0026] like Figure 1-3 As shown, a plastic coating device for the inner wall of metal pipes includes a pit 1, a PLC controller, and a device body. The device body includes a base 2 mounted on the ground immediately behind the pit 1; a mounting frame 9 is mounted on the side of the base 2 closest to the pit 1; a turntable 5 is rotatably mounted on the side of the mounting frame 9 closest to the pit 1; a connecting plate is fixed to the side of the turntable 5 furthest from the mounting frame 9. A hopper 7 is installed inside the pit 1; a fixed platform 701 is mounted on the top of the hopper 7; the rear end of the fixed platform 701 is fixed to the front end of the connecting plate near the bottom. In use, the hopper 7 rotates 360° clockwise or counterclockwise along with the turntable 5 via the connecting plate.

[0027] Preferably, a servo motor 3 is installed on the top of the base 2, and the output shaft of the servo motor 3 is connected to the central shaft of the turntable 5 through a reducer 4, thereby realizing the rotation of the turntable 5.

[0028] Preferably, the top wall of the fixed platform 701 has a pipe fixing port 7011 in the middle; the hopper box 7 has a hopper opening corresponding to the position of the pipe fixing port 7011, and a hopper door is provided at the hopper opening, which is controlled to open and close by a cylinder or a hydraulic cylinder (not shown in the figure).

[0029] Preferably, the hopper 7 is filled with one of the following plastic powders: linear low-density polyethylene powder (LLDPE), high-density polyethylene powder (HDPE), polypropylene powder (PP), or polytetrafluoroethylene powder (PTFE), for coating the inner wall of the pipe.

[0030] Preferably, the top wall of the fixing platform 701 is provided with at least two independently controlled hydraulic clamps 8 around the pipe fixing port 7011 (the specific number of hydraulic clamps is determined according to the pipe diameter, and is not considered as a further limitation of this utility model), which are used to firmly fix the metal pipe to be coated on the device.

[0031] Preferably, the servo motor 3, the cylinder or the hydraulic cylinder are all controlled by a PLC controller.

[0032] Preferably, the connecting plate includes a support frame 10 and an arc-shaped pipe rack 6 installed on the edge of the support frame 10. To avoid imbalance during rotation caused by a large mass of pipe, a counterweight fixing plate 1001 is provided on the top of the side of the support frame 10 away from the fixed platform 701. When the weight of the metal pipe is large, a counterweight block needs to be added at the counterweight fixing plate 1001.

[0033] To facilitate operators in sealing the openings of large-sized pipes, a ladder 11 is provided on either the left or right side of the mounting frame 9.

[0034] More preferably, the device further includes several sealing plates that match the diameter of the flange of the metal pipe to be coated, several pipe fixing port adjustment plates, and several C-type clamps for fixing the sealing plates.

[0035] The following is a detailed explanation of the working principle and coating process of this device, including the following steps:

[0036] S1 performs sandblasting on the metal pipe to be coated to remove the oxide layer on its surface and blows away the surface residue with compressed air;

[0037] S2 places the pre-treated metal pipe into a heating furnace and heats it to the melting temperature of the plastic coating material in the hopper (240℃~320℃, depending on the type of plastic coating material), ensuring that the temperature difference does not exceed ±10℃;

[0038] S3 Select a pipe fixing port adjustment plate and a sealing plate that match the pipe diameter of the metal pipe flange, and place the pipe fixing port adjustment plate at the pipe fixing port.

[0039] S4 uses hoisting equipment to align one of the flanges at the pipe end of the heated metal pipe with the pipe fixing adjustment plate and adjusts the hydraulic clamps to firmly fix the metal pipe at the pipe fixing port; at the same time, C-clamps are used to seal the sealing plate with the other flanges at the pipe ends of the metal pipe; depending on the actual weight of the metal pipe, it is determined whether a counterweight needs to be set on the counterweight fixing plate to ensure that there is no imbalance during rotation.

[0040] The S5 opening device (in the initial state, the hopper is located in the pit and the hopper door is closed) connects to the turntable, which rotates clockwise. When the hopper reaches its highest point, the PLC controller stops the servo motor and simultaneously controls the cylinder to open the hopper door. A large amount of coating material enters the inner cavity of the metal pipe. To ensure that the coating material completely fills the inner cavity of the pipe, the hopper door is open for 5-15 seconds (the specific replenishment time is set according to the size, length, and film thickness of the pipe). Then the hopper door automatically closes, and the connecting plate continues to rotate clockwise to coat the inner wall. In each subsequent rotation of the coating process, the hopper door opens when the hopper rotates to a position 10° away from the highest point, and automatically closes when the hopper rotates away from the highest point. This replenishment process is repeated after each rotation to ensure that the inner cavity is always filled with coating material. (It is worth noting that after the first rotation of coating material filling, the rotation does not stop; only the opening and closing state of the hopper door needs to be changed.)

[0041] S6 maintains its current state and rotates clockwise 3 to 5 times (the specific number of fusion turns is set according to the size, length and film thickness of the pipe) until the hopper returns to the initial position at the lowest point in the pit. Using centrifugal force and gravity, the inner wall of the metal pipe is completely covered with the plastic coating material, thus completing the plastic coating of the inner wall surface, and then entering the plastic coating material recycling stage.

[0042] The S7 connecting plate drives the hopper to rotate counterclockwise and then clockwise 2 to 4 times each (the specific number of recycling rotations is set according to the size, length and film thickness of the pipe to ensure that the residual plastic coating material in the inner cavity of the irregularly shaped pipe can be recycled as much as possible). Unlike the plastic coating process, during the recycling process, the hopper door opens whenever the hopper rotates to a position close to the lowest point of 60°, and automatically closes when the hopper rotates away from the lowest point of 60°, so that the plastic coating material in the inner cavity of the metal pipe is recycled back into the hopper.

[0043] S8 removes the metal pipe with the inner wall plastic coating and uses a temperature measuring pen to check its surface temperature. If it is lower than the melting temperature of the plastic coating material, it is heated a second time using a handheld heat gun to further fuse the plastic coating material and the inner wall of the metal pipe.

[0044] S9 performs water cooling treatment on the metal pipe after secondary fusion in S8 to improve the coating's corrosion resistance, wear resistance and impact resistance.

[0045] S10 performs grinding on the end face of the metal pipe that is connected to the pipe fixing port adjustment plate, and measures the thickness of the end face along the circumferential direction, with an allowable error of ±0.5mm.

[0046] S11 performs an electric spark test to check for defects such as welding pores and protrusions in the plastic coating and repairs the defects.

[0047] S12 performs subsequent treatments such as sandblasting, painting, and packaging on the outer surface of metal pipes according to user requirements.

[0048] It is worth noting that the various rotation nodes, durations, control switches, etc. in this utility model can all be achieved using known existing electrical components, control programs, and program instructions. Here, we will not go into too much detail about how the specific known control programs and software work together.

[0049] This invention features a reasonable structure, convenient operation, no need for repeated heating, applicability to multiple pipe diameters, and the coating process does not rely on manual operation experience. The cleanliness requirements for the inner wall of the metal pipe are lower than those for general coating, only requiring Sa2.0 or higher. Compared to traditional coating processes, this invention provides a more uniform coating effect without sagging or missed coating. Furthermore, excess powder material is easy to recycle, effectively improving the reuse rate of powder.

[0050] In this utility model, terms such as "upper," "lower," "bottom," and "top" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are merely used to facilitate the description of the structural relationships of the various components or elements of this utility model and do not specifically refer to any component or element in this utility model, nor should they be construed as limiting the utility model. Terms such as "connected" and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be determined according to the specific circumstances, and they should not be construed as limiting the utility model.

[0051] Of course, the above description is not intended to limit the present utility model, and the present utility model is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present utility model should also fall within the protection scope of the present utility model.

Claims

1. A plastic coating device for the inner wall of metal pipes, characterized in that, Includes the pit, PLC controller, and device body; The device body includes a base installed close to the ground behind the pit; a mounting frame is provided on the top of the base near the pit; a turntable is rotatably provided on the side of the mounting frame away from the base; and a connecting plate is fixed on the side of the turntable near the pit. A hopper is installed inside the pit; a fixed platform is installed on the top of the hopper; the rear end of the fixed platform is fixed to the bottom of the front end of the connecting plate. The hopper is rotated 360° clockwise or counterclockwise along with the turntable via a connecting plate.

2. The plastic coating device for the inner wall of metal pipes according to claim 1, characterized in that, A servo motor is mounted on the top of the base, and the output shaft of the servo motor is connected to the central shaft of the turntable through a reducer.

3. The plastic coating device for the inner wall of metal pipes according to claim 2, characterized in that, The fixing platform has a pipe fixing port in the middle; The hopper box is provided with a hopper opening corresponding to the fixed opening of the pipe, and a hopper door is provided at the hopper opening. The hopper door is controlled to open and close by a cylinder or a hydraulic cylinder.

4. The plastic coating device for the inner wall of metal pipes according to claim 3, characterized in that, At least two independently controlled hydraulic clamps are evenly spaced around the pipe fixing opening on the top of the fixing platform.

5. The plastic coating device for the inner wall of metal pipes according to claim 4, characterized in that, The servo motor, cylinder, or hydraulic cylinder are all electrically connected to the PLC controller.

6. The plastic coating device for the inner wall of a metal pipe according to claim 5, characterized in that, The connecting plate includes a support frame and an arc-shaped tube frame installed on the edge of the support frame; A counterweight fixing plate is provided on the top of the side of the support frame away from the fixed platform.

7. The plastic coating device for the inner wall of metal pipes according to claim 1, characterized in that, A ladder is provided on the left or right side of the mounting frame.

8. The plastic coating device for the inner wall of metal pipes according to claim 1, characterized in that, The plastic coating material inside the hopper is one of linear low-density polyethylene powder, high-density polyethylene, polypropylene, or polytetrafluoroethylene.

9. The plastic coating device for the inner wall of a metal pipe according to claim 6, characterized in that, It also includes several sealing plates that match the diameter of the metal pipe flanges, several pipe fixing adjustment plates, and several C-clamps.

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