Pumping and spraying device for pipe die coating of centrifugal casting pipe

Abstract

The utility model discloses a centrifugal casting pipe die coating pumping and spraying device, and belongs to the field of centrifugal casting, the centrifugal casting pipe die coating pumping and spraying device comprises a stirring mechanism, a pumping mechanism and a spray head mechanism, the pumping mechanism comprises a screw feeding device arranged below a feeding port and a mechanical pump for conveying material liquid to the spray head mechanism through a material pipe, a discharging port of the stirring mechanism is connected with a feeding port of the pumping mechanism, the spray head mechanism comprises a fan-shaped nozzle connected with a material pipe through a spray head rotating device, and the fan-shaped nozzle is connected with high-pressure air through an air pipe. According to the device, paint is sprayed to the bellmouth position of the inner wall of the pipe die in the casting gap, drying is conducted through waste heat of the pipe die, the paint serves as an isolation layer of the pipe die and a bulb pipe, and high-temperature strain and mechanical stress borne by the position are reduced. The use time of the cold mold method pipe mold is prolonged, and the pipe mold cost is reduced.

Description

Technical Field

[0001] The present application belongs to the technical field of centrifugal casting, and in particular to a pumping and spraying device for coating of centrifugal casting pipe molds, which prolongs the life of cold molds of ductile iron pipes. Background Art

[0002] Ductile iron pipes are formed by centrifugal casting, and small and medium-sized ductile iron pipes are formed by the cold mold method. During the cold mold process of centrifugal casting of ductile iron pipes, molten iron is directly poured into the pipe mold, the outer wall of the pipe mold is sprayed and cooled, the cast pipe is pulled out after forming, and the next one is cast. The inner wall of the cold mold pipe mold is in direct contact with the molten iron, and the outer surface is in direct contact with the cooling water. The inner wall of the pipe mold is cyclically subjected to high temperature stress and mechanical stress, and the inner wall of the pipe mold is prone to cracking, especially the socket position of the inner wall of the pipe mold. The pipe mold cracks, the cast pipe is embedded in the gap, and it is difficult to pull the pipe, which affects the continuity of production; replacing the pipe mold affects the output of the shift; the accumulation of fatigue damage will also reduce the total life of the pipe mold. Therefore, there is an urgent need for a pumping spray device to extend the life of the cold mold pipe mold of ductile iron pipes. Summary of the invention

[0003] The purpose of this application is to provide a pumping spraying device for coating of centrifugal cast pipe molds, aiming to solve the above problems. In the casting gap of ductile iron pipes, the device is used to spray coating on the socket end of the pipe mold, and the coating is dried with the help of the residual heat of the pipe mold. The coating serves as an isolation layer between the pipe mold and the spherical tube, reducing the thermal stress and mechanical stress of the inner wall of the pipe mold. The use of this device prolongs the service life of cold mold pipe molds, reduces the replacement frequency, improves production efficiency, increases the total life of cold mold pipe molds, and reduces production costs.

[0004] In order to achieve the above technical objectives, this application adopts the following technical solutions:

[0005] A pumping spraying device for coating of a centrifugal casting pipe mold comprises a stirring mechanism, a pumping mechanism and a nozzle mechanism, wherein the pumping mechanism comprises a spiral feeding device arranged below a feed port and a mechanical pump for conveying liquid to the nozzle mechanism through a feed pipe, the discharge port of the stirring mechanism is connected to the feed port of the pumping mechanism, the nozzle mechanism comprises a fan-shaped nozzle connected to the feed pipe through a nozzle rotating device, and the fan-shaped nozzle is connected to high-pressure air through an air pipe.

[0006] A further improvement of the technical solution of the utility model is that the stirring mechanism comprises a stirring box provided with a stirring paddle, a discharge port and a baffle are provided on the side of the stirring box, and a stirring motor connected to the stirring paddle is provided at the bottom of the stirring box.

[0007] A further improvement of the technical solution of the utility model is that the pumping mechanism also includes a pumping box and a motor arranged on one side of the pumping box for driving a spiral feeding device, a feed port is arranged at the top of the pumping box, and spiral blades and a spiral shaft are arranged at the bottom, the bottom of the pumping box is connected to the material pipe and a mechanical pump is arranged to transport the material liquid in the pumping box to the nozzle mechanism through the material pipe.

[0008] A further improvement of the technical solution of the utility model is that the mechanical pump can be selected from one of a screw pump, a diaphragm pump, a plunger pump, a slurry pump, a centrifugal pump or a gear pump.

[0009] A further improvement of the technical solution of the utility model is that: the nozzle mechanism further includes a nozzle baffle plate arranged on the nozzle rotating device, and the fan-shaped nozzle is in an arc shape.

[0010] A further improvement of the technical solution of the utility model is that the nozzle rotating device can rotate 30°-90° clockwise and counterclockwise, while driving the fan-shaped nozzle and the nozzle baffle to rotate, and the heat insulation material is wound around the fan-shaped nozzle.

[0011] A further improvement of the technical solution of the utility model is that: the mixing box is a cylindrical box with an open upper end, and a cover is arranged on the mixing box.

[0012] A further improvement of the technical solution of the utility model is that a discharge hole is arranged at the bottom of the pumping box.

[0013] A further improvement of the technical solution of the utility model is that the pumping spraying device is installed on one side of the centrifugal casting machine, and in the process of waiting for spraying, the nozzle baffle is located between the fan-shaped nozzle and the pipe mold of the centrifugal casting machine.

[0014] A further improvement of the technical solution of the utility model is that an electric valve is arranged on the air pipe, and the electric valve, the stirring motor, the mechanical pump and the nozzle rotating device are uniformly controlled by a control system.

[0015] Due to the adoption of the above technical solution, the technical effects achieved by this application are as follows:

[0016] The pumping spray device of the present application sprays paint on the socket position of the pipe mold during the casting gap, and uses the residual heat of the pipe mold to dry it. The paint serves as an isolation layer between the pipe mold and the ball tube, reducing the high temperature strain and mechanical stress at this position, extending the use time of the cold mold pipe mold, improving production efficiency, increasing the overall life of the cold mold pipe mold, and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of the pumping spraying device of the utility model;

[0018] Figure 2This is a schematic diagram of the assembly of the pumping spraying device of the utility model on a centrifuge;

[0019] Wherein: 1. stirring mechanism, 101. stirring box, 102. discharge port, 103. stirring paddle, 104. stirring motor, 2. pumping mechanism, 201. pumping box, 202. feed port, 203. electric valve, 204. air pipe, 205. discharge hole, 206. material pipe, 207. motor, 208. spiral feeding device, 209. mechanical pump, 3. nozzle mechanism, 301. fan-shaped nozzle, 302. nozzle rotating device, 303. nozzle baffle, 4. pipe mold driving motor, 6. pipe mold, 7. upper core frame. DETAILED DESCRIPTION

[0020] The technical solution of the present application is described in detail below in conjunction with specific implementation methods.

[0021] See also Figure 1 In this embodiment, a pumping spraying device for coating of a centrifugal casting pipe mold includes a stirring mechanism 1, a pumping mechanism 2 and a nozzle mechanism 3. The pumping mechanism 2 includes a spiral feeding device 208 arranged below a feed port 202 and a mechanical pump 209 for conveying liquid to the nozzle mechanism 3 through a feed pipe 206. The discharge port 102 of the stirring mechanism 1 is connected to the feed port 202 of the pumping mechanism 2. The nozzle mechanism 3 includes a fan-shaped nozzle 301 connected to the feed pipe 206 through a nozzle rotating device 302. The fan-shaped nozzle 301 is connected to high-pressure air through an air pipe 204.

[0022] The stirring mechanism 1 comprises a stirring box 101 provided with a stirring paddle 103, a discharge port 102 and a baffle are provided on the side of the stirring box 101, and a stirring motor 104 is provided at the bottom of the stirring box 101 and connected to the stirring paddle 103. The stirring mechanism 1 is used to stir and mix the coating, and the discharge port of the stirring mechanism is connected to the pumping mechanism 2. In addition to the spiral feeding device 208 and the mechanical pump 209, the pumping mechanism 2 also comprises a pumping box 201 and a motor 207 provided at one side of the pumping box 201 for driving the spiral feeding device. The top of the pumping box 201 is provided with a feed port 202, and the bottom is a spiral blade and a spiral shaft of the spiral feeding device 208. The bottom of the pumping box 201 is connected to the material pipe 206 and a mechanical pump 209 is provided to transport the material liquid in the pumping box 201 to the nozzle mechanism 3 through the material pipe 206.

[0023] The nozzle mechanism includes a nozzle rotating device 302 and a fan-shaped nozzle 301, and also includes a nozzle baffle 303 arranged on the nozzle rotating device 302. The fan-shaped nozzle 301 is in an arc shape. The nozzle mechanism can be turned over and connected to high-pressure air to further disperse the paint and improve the uniformity of the coating. The spiral spray is used at the pipe mold socket to increase the cooling strength of the pipe mold socket.

[0024] The mixing box 101 is arranged horizontally, a cylindrical box, driven by a mixing motor 104 at the bottom, with a discharge port and a baffle on the side. A lid is provided on the mixing box 101, and coating raw materials and water are put into the mixing box 101 from the top, and the lid is covered for mixing. After the mixing is completed, the discharge port baffle is opened to discharge the materials, and the discharge port is connected to the pumping box 201.

[0025] The pumping box 201 is a paint storage box, and a spiral feeding device is provided at the bottom to prevent the paint from settling and stratifying. The left bottom of the pumping box is connected to a mechanical pump 209. The mechanical pump 209 can be a screw pump, a diaphragm pump, a plunger pump, a slurry pump, etc. The mechanical pump and the spiral feeding device are controlled by a motor. The mechanical pump 209 is used as a paint delivery power to deliver the paint to the nozzle mechanism 3 through the material pipe 206. Preferably, a discharge hole 205 is provided at the bottom of the pumping box 201.

[0026] The nozzle mechanism 3 includes a fan-shaped nozzle 301, a nozzle rotating device 302, and a nozzle baffle 303. The fan-shaped nozzle 301 is in an arc shape and is connected to a high-pressure air pipe. The nozzle is wrapped with a heat-insulating material to isolate heat radiation, reduce the nozzle temperature, and prevent the internal residual paint from drying. Before spraying, the nozzle rotating device 302 rotates clockwise by 30°-90°, and the fan-shaped nozzle 301 faces the pipe mold 6. First, the electric valve 203 on the air pipe is opened to purge the residual paint, and then the mechanical pump 209 is opened for spraying. After the spraying is completed, only the mechanical pump 209 is closed to purge the dust on the surface of the paint layer, and then the electric valve 203 is closed. The nozzle rotating device 302 rotates counterclockwise by 30°-90°, and the fan-shaped nozzle 301 faces downward. The nozzle baffle is located between the fan-shaped nozzle and the pipe mold 6 to block the splashing molten iron during the centrifugal production process, reduce heat radiation, and reduce the temperature of the fan-shaped nozzle 301.

[0027] The centrifugal casting pipe mold is equipped with a system spray, which is a conventional technology. A spiral spray is used at the socket end of the pipe mold, a spiral water spray pipe is arranged at the socket end of the centrifuge, and spray holes are added to increase the cooling speed of the socket by increasing the amount of water sprayed. Deionized water, softened water, and distilled water are preferred for system spraying.

[0028] The electric valve, stirring motor, mechanical pump and nozzle rotating device are centrally controlled by the control system to achieve semi-automatic control and automatic control.

[0029] The equipment installation is completed. The specific implementation steps are as follows:

[0030] S0, mixing, putting various raw materials of the coating into the stirring box 101, turning on the stirring motor 104 for stirring, testing the coating viscosity, opening the discharge port 102 after passing the test, and placing the coating into the pumping box 201;

[0031] S1. Purge before spraying. After the ductile iron pipe is pulled out, the centrifuge moves upward, the nozzle rotating device 302 rotates 90° clockwise, the fan-shaped nozzle 301 faces the position 100-1000mm of the pipe mold socket, the electric valve 203 is opened, and the air is blown to purge the residual paint in the pipe mold 6 for 3 seconds, while keeping the pipe mold 6 rotating at a low speed;

[0032] S2, spraying, start the mechanical pump 209, and spray the paint with the fan-shaped nozzle 301 toward the socket 100-1000mm of the pipe mold 6 for 4 seconds, and keep the pipe mold 6 rotating at a low speed;

[0033] S3, purge after spraying, only close the mechanical pump 209, keep the electric valve 203 open, purge the dust on the surface of the coating layer, 3 seconds, close the electric valve 203, the nozzle rotating device 302 rotates 90° counterclockwise, the fan-shaped nozzle 301 faces downward, the nozzle baffle 303 is located between the fan-shaped nozzle 301 and the tube mold 6, and the tube mold 6 is kept rotating at a low speed;

[0034] S4, core mounting, the core rack 7 installs the sand core, and gradually increases the speed of the tube mold driving motor 4, thereby increasing the speed of the tube mold 6;

[0035] S5, casting, the centrifuge is in place, the speed of the tube mold 6 is in place, the fan-shaped bag is turned over, the molten iron flows into the socket of the tube mold 6 through the flow channel, the centrifuge moves downward, and the flow channel exits;

[0036] S6, pipe drawing, molten iron solidifies, the temperature of the ductile iron pipe drops to 500-800°C, the upper core frame 7 withdraws, the pipe drawing tongs draw the pipe, the next pipe is cast, and S2-S6 are repeated;

[0037] During the above process, the spray system on the outer wall of the pipe mold is kept open normally.

[0038] The device of the present application sprays paint on the socket position of the pipe mold during the casting gap, and uses the residual heat of the pipe mold to dry it. The paint serves as an isolation layer between the pipe mold and the ball tube, reducing the high-temperature strain and mechanical stress at this position, extending the service life of the cold mold pipe mold, improving production efficiency, increasing the total life of the cold mold pipe mold, and reducing production costs.

[0039] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0040] Although embodiments of the present invention have been proposed and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A pumping spraying device for centrifugal casting pipe mold coating, characterized in that: The invention comprises a stirring mechanism (1), a pumping mechanism (2) and a nozzle mechanism (3); the pumping mechanism (2) comprises a spiral feeding device (208) arranged below a feed port (202) and a mechanical pump (209) for conveying liquid material to the nozzle mechanism (3) through a material pipe (206); the discharge port (102) of the stirring mechanism (1) is connected to the feed port (202) of the pumping mechanism (2); the nozzle mechanism (3) comprises a fan-shaped nozzle (301) connected to the material pipe (206) through a nozzle rotating device (302); and the fan-shaped nozzle (301) is connected to high-pressure air through an air pipe (204).

2. A pumping and spraying device for centrifugal casting pipe mold coating according to claim 1, characterized in that: The stirring mechanism (1) comprises a stirring box (101) provided with a stirring paddle (103), a material discharge port (102) and a baffle plate are provided on the side of the stirring box (101), and a stirring motor (104) connected to the stirring paddle (103) is provided at the bottom of the stirring box (101).

3. A pumping and spraying device for centrifugal casting pipe mold coating according to claim 2, characterized in that: The pumping mechanism (2) further comprises a pumping box (201) and a motor (207) arranged on one side of the pumping box (201) for driving a spiral feeding device; a feed port (202) is arranged on the top of the pumping box (201), and spiral blades and a spiral shaft are arranged on the bottom; the bottom of the pumping box (201) is connected to a material pipe (206) and a mechanical pump (209) is arranged to transport the material liquid in the pumping box (201) to the nozzle mechanism (3) through the material pipe (206).

4. The pumping and spraying device for centrifugal casting pipe mold coating according to claim 1 is characterized in that: The mechanical pump (209) may be selected from one of a screw pump, a diaphragm pump, a plunger pump, a slurry pump, a centrifugal pump or a gear pump.

5. The pumping and spraying device for centrifugal casting pipe mold coating according to claim 1, characterized in that: The nozzle mechanism further comprises a nozzle baffle (303) arranged on the nozzle rotating device (302), and the fan-shaped nozzle (301) is in an arc shape.

6. A pumping and spraying device for centrifugal casting pipe mold coating according to claim 5, characterized in that: The nozzle rotating device (302) can rotate 30°-90° clockwise and counterclockwise, and simultaneously drive the fan-shaped nozzle (301) and the nozzle baffle (303) to rotate, and the heat insulation material is wound around the fan-shaped nozzle (301).

7. The pumping and spraying device for centrifugal casting pipe mold coating according to claim 2, characterized in that: The mixing box (101) is a cylindrical box with an open top, and a cover is provided on the mixing box (101).

8. The pumping and spraying device for centrifugal casting pipe mold coating according to claim 3, characterized in that: A discharge hole (205) is provided at the bottom of the pumping box (201).

9. The pumping and spraying device for centrifugal casting pipe mold coating according to claim 1, characterized in that: The pumping spraying device is installed on one side of the centrifugal casting machine. During the process of waiting for spraying, the nozzle baffle (303) is located between the fan-shaped nozzle (301) and the pipe mold (6) of the centrifugal casting machine.

10. The pumping and spraying device for centrifugal casting pipe mold coating according to claim 3, characterized in that: The air pipe (204) is provided with an electric valve (203), and the electric valve, the stirring motor (104), the mechanical pump (209) and the nozzle rotating device (302) are uniformly controlled by a control system.

Images