KR100770315B1 - A inside diameter coating apparatus and method of a small pipe - Google Patents

Abstract

A device and a method for coating an inner diameter of a small-diameter pipe are provided to form a coating film of uniform thickness all the time by depositing powder on the inside of the pipe with passing the powder through a metal pipe by a powder delivering method using a compressor and an electrostatic method. A device for coating an inner diameter of a small-diameter pipe(10) is composed of a power supply unit(2) applying power to metal materials having a predetermined inner diameter; guide units(4,4') installed at both input units of the material to guide the transferring of powder; an electrostatic coating unit(6) connected to the guide unit to spray powder on the inside after making the powder in an electrostatic state; a blowing unit(8) connected to the electrostatic coating unit to supply the air at predetermined pressure; a rotating unit(12) driving the material to be rotated at 360 degrees; and a thermo-curing unit(14) curing the powder deposited on the inner diameter of the pipe by supplying a heat source to the material.

Description

A diameter coating apparatus and method of a small pipe

1 is a block diagram showing an inner diameter deposition apparatus of a pipe according to the prior art.

Figure 2 is a schematic diagram showing an embodiment configuration of the inner diameter coating apparatus of a small diameter pipe according to the present invention.

Figure 3 is a flow chart showing the inner diameter coating method of small diameter pipe according to the present invention.

* Explanation of symbols for main parts of the drawings

2: power supply 4, 4 ': jig

6: blackout machine 8: compressor

10: Hopper 12: Rotator

14: thermosetting device

The present invention relates to an apparatus and a method for coating an inner diameter of a small diameter pipe, and more particularly, to form a coating film having a uniform thickness by using a powder electrostatic method to obtain a standardized product and to increase the corrosion resistance of the pipe and the surface of the coated surface. The present invention relates to an inner diameter coating apparatus and method for small diameter pipes that can obtain characteristics.

In general, metal pipes are used for transporting powder or fluid by being piped to various plant facilities or infrastructure facilities, and are widely used as constituent materials of machines and structures. These pipes are classified into metal or non-metal according to the material. In the case of metal pipes, the pipes are manufactured by bending thin plates and welding or single welding, or by rolling in a bar.

However, since the main function of the metal pipe is to transport the fluid, there is a problem in that the corrosive fluid is transported or the moisture is corroded in the pipe and the life is shortened. In addition, the corroded scale has another problem of solidifying with time and acting as a cause of blocking the inside of the pipe to inhibit the flow of the fluid. Therefore, in the case of metal pipes mainly transporting the corrosion-causing fluid, the corrosion resistance to prevent corrosion on the inner diameter is coated or the pipe itself is made of a galvanized pipe or copper pipe having a high corrosion resistance. In the case of the pipe coated with the former rust preventive material, there is a problem in that it can not be homogeneous, and because the coating thickness is thin and the adhesive strength is weak, peeling easily. Pipes made of the latter copper or galvanized material not only have a disadvantage of being expensive, but also have a high possibility of being exposed to corrosion as the service life increases, and thus, there is a problem of replacing the fuse or coating the inside of the pipe. .

On the other hand, Korean Patent Publication No. 1985-0004408 has proposed a synthetic resin coating method of the inner diameter of the metal pipe. This technique heats the metal pipe P, injects compressed air into the metal pipe P through the compressor C, and drives the piston 104 provided in the cylinder 102 as shown in FIG. This is a method of depositing the synthetic resin powder on the inner diameter of the metal pipe while inserting the ejection nozzle 106 into the metal pipe P.

However, the above technique can adjust the deposition thickness according to the capacity of the compressor (C), the forward and backward movement speed of the jet pipe 108 and the size of the nozzle jet hole (106a), but the jet hole of the jet nozzle 106 ( Since 106a) is not a structure ejected in 360 ° forward, it is not possible to form a coating layer of uniform distribution over the entire inner diameter of the metal pipe.

Since the above method is a deposition method by the forward and backward driving of the piston, it is possible to coat a straight pipe, but in the case of a bent pipe such as a semi-curve pipe or a spiral pipe, it cannot be coated. In particular, in the above method, since the ejection nozzle should be inserted into the inside of the metal pipe, it is difficult to coat the pipe within a small diameter, for example, Φ30, the thickness of the coating film is not uniform, and the operation is impossible at room temperature.

Therefore, the present invention has been proposed to solve the above problems, by using a powder electrostatic method and a blowing method to spread the powder inside a small diameter pipe to deposit at room temperature to form a coating layer having a uniform thickness It is an object of the present invention to provide an inner diameter coating apparatus and a method of a bore pipe.

In addition, the present invention provides an inner diameter coating apparatus and method for small diameter pipes that can be coated with a uniform thickness regardless of the shape of the metal pipe and the shape having various cross sections, that is, straight, curved, spiral, and the like. There is a purpose.

In order to achieve the above object, the present invention provides a power supply means for applying power to a metal material having any inner diameter; Guide means installed at both input portions of the material and for guiding the conveyance of the powder; Electrostatic coating means connected to the guide means, for electrostatically discharging the powder as an adherend therein; Blowing means connected to the electrostatic painting means for providing air blowing at an arbitrary pressure; Rotating means for driving the material to rotate 360 °; And it provides an inner diameter coating device of a small diameter pipe including a heat source for providing a heat source to the material to cure the powder deposited on the inner diameter.

In addition, the present invention comprises a first step of supplying powder to the electrostatic coating through the hopper; Operating a compressor to provide blowing force to the powder nozzle at any pressure; A third step of mounting the material on the rotating device and connecting one side jig to the electrostatic coating device; A fourth step of ejecting the electrostatic powder to one of the jigs provided at both ends of the material having an arbitrary inner diameter from the electrostatic coating machine by using the blowing force; And a fifth step of depositing the powder passing through the material on the inner surface by applying the power to the material and causing (+) and (-) electrification to the inner surface, the powder on the inner surface of one side section of the material. After the deposition is completed, the material is rotated 180 ° and the internal diameter coating method of the small-diameter pipe, characterized in that for performing the ejection process of the electrostatic powder of the fourth step and the charging step of the fifth step again. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings of FIGS. 2 and 3.

Inner diameter coating apparatus and method of small diameter pipe according to the present invention by depositing powder of uniform thickness to the inner diameter of the metal pipe at room temperature using the powder electrostatic method, can be coated inside diameter of small diameter pipe without being bound to various shapes It is implemented.

Embodiment of the present invention, as shown in Figure 2, the power supply unit for applying (+) or (-) power to the material having a certain inner diameter, that is, the metal pipe 100; A jig (4, 4 ') installed at one or both ends of the metal pipe (100) to guide the transfer of the electrostatic powder; An electrostatic sealer (6) installed at the tip of the nozzle for connecting to the jig (4, 4 ') and for injecting the electrostatic powder on the inner surface of the pipe; A compressor (8) connected to the rear end of the electrostatic coating machine (6) to provide air blowing at an arbitrary pressure; A hopper 10 for providing powder to the electrostatic coating machine 6; It includes a rotary device 12 for driving the material to rotate 360 ° and a heat curing device 14 for providing a heat source to the metal pipe 100 to cure the powder deposited on the inner diameter.

In an embodiment of the invention, the jig 4, 4 'utilizes the principle of a venturi tube. In other words, in the fluid flowing through the conduit, Bernoulli's law of incompressible fluid is applied to reduce the pressure and increase the speed when the area of the conduit is reduced. The jig (4, 4 ') is to ensure that the blowing air is uniformly and quickly diffused into the metal pipe 100, and prevent vortex during the diffusion of the powder. If there is no jig (4, 4 '), when the powder is discharged, the vortex is formed by the diffusion pressure of the powder at the outlet side of the metal pipe 100, which causes the uniform deposition thickness can not be formed It will work.

The jig (4, 4 ') and the connecting portion 16 is connected to the hole of the metal pipe 100; It consists of an extension 18 which extends at any angle in the connection 12. The jig 4 has a substantially funnel shape. The length L of the connecting portion 16 is proportional to the length of the metal pipe 100. However, the connection 16 may be removed as necessary. In this case, the jig 4 has a conical cross section.

The preferred slope angle θ of the extension 18 is 3 ° to 8 °. This is to speed up the time for the powder to reach the outlet from the inlet of the metal pipe 100 and at the same time to form the deposition thickness of the powder uniformly. That is, when the inclination of the expansion portion 18 is 3 ° or less, the blowing force should be increased because the powder reaches the outlet of the metal pipe 100 only by the ejection speed from the electrostatic coating machine 6. In addition, when the inclination angle θ of the expansion portion 18 is 8 ° or more, the pressure is increased instead of decreasing the pressure. Therefore, since the powder passes quickly through the metal pipe 100 without a time margin to be deposited, the efficiency of being deposited on the inner surface of the metal pipe 100 can be reduced.

Next, the inner diameter coating method of the small diameter pipe according to the present invention will be described with reference to FIG.

First, the powder is supplied to the electrostatic coating machine 6 through the hopper 10 (S10). Then, the compressor 8 is operated to complete the preparation for providing the blowing force of an arbitrary pressure to the electrostatic coating machine 6 (S20). At this time, the electrostatic coating machine 6 electrostatics the powder.

Next, the material to coat the inner diameter is mounted on the rotating device 12, and the jig 4 is connected to the tip nozzle of the electrostatic coating machine 6 (S30 and S40).

The electrostatic powder is ejected from the electrostatic coating machine 6 to the jig 4 provided at the inlet side of the metal pipe 100 having an arbitrary inner diameter by using the blowing force generated in the compressor 8 (S50). .

The powder is introduced into the metal pipe 100 at any flow rate through the jig (4). At this time, by applying power to the metal pipe 100 to cause the electrostatic powder and the (+), (-) charging the powder passing through the metal pipe 100 is deposited on the inner surface of the metal pipe.

In the embodiment of the present invention, the powder has a size (usually 3 ~ 50㎛ size) that can be injected into the electrostatic sprayer (6). In addition, the blowing force generated in the compressor (8) is 2 to 3kgf / ㎠ based on the case that the length of the metal pipe 100 is 1m, the inner diameter is 25mm, this condition is proportional to the length and inner diameter of the metal pipe do. According to the experimental results of the present applicant, when the inner diameter coating of the metal pipe having a length of 1m and the inner diameter of 25mm, when the blowing pressure is 2kgf / ㎠ or less, the power output of the powder is reduced and the deposition efficiency on the inlet side of the metal pipe is good. However, the outlet side is not deposited, and the powder is deposited on the inner diameter of the metal pipe 100 at the time of transport and falls by its own weight. In addition, when the blowing pressure is 3kgf / ㎠ or more, the powder deposition thickness is thin at the inlet of the metal pipe 100, the powder is discharged quickly from the outlet side of the metal pipe 100 without the time to be deposited is not deposited. Will not.

After the injection of the powder to the inlet side of the metal pipe 100 is completed, the rotary device 12 is driven to rotate the metal pipe 100 by 180 °, and the same process is performed once more (S60). , S70). At this time, the jig 4 'installed on the outlet side of the metal pipe 100 also rotates together. The jig 4 'is connected to the electrostatic coating machine 6, and a blowing force is provided to the electrostatic coating machine 6 through the compressor. The electrostatic powder is introduced into the outlet metal pipe 100, the powder is deposited on the inner surface of the metal pipe 100 by the electrostatic force. At this time, the powder at the time of the first injection and the powder at the time of the second injection are introduced in a 1: 1 ratio. By this process, the inner surface of the metal pipe 100 is deposited with a uniform thickness.

When the deposition of the powder on the inner surface of the metal pipe 100 is completed, the thermosetting device 14 is operated to cure the powder and complete (S80).

According to the metal pipe inner diameter coating method using the above-mentioned powder electrostatic, it can be applied to small-diameter pipe of the inner diameter of φ3 ~ φ70. In addition, since the powder is transported into the metal pipe by the blowing force, the cross section of the metal pipe 100 has a circular, square, honeycomb shape, or the appearance of the metal pipe 100 is a straight pipe as well as elbow. Even if it is formed into any shape such as semi-curved shape or spiral shape, it is possible to deposit uniform thickness. In particular, when the cross-sectional area of the metal pipe 100 is reduced and enlarged, it may be possible to deposit a uniform thickness when the expanded width is within 20% of the diameter.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be apparent to those of ordinary skill in Esau.

As described above, according to the present invention, the metal pipe is deposited while the metal pipe passes through the powder delivery method using the powder electrostatic method and the compressor, thereby having an effect of always forming a film having a uniform thickness.

In addition, the present invention is capable of coating a uniform inner diameter regardless of the shape of the metal pipe and the shape having various cross sections, that is, straight, curved, spiral, etc., and has other effects applicable to small diameter pipes.

Claims (7)

Power supply means for applying power to a metallic material having an arbitrary inner diameter; Guide means installed at both input portions of the material and for guiding the conveyance of the powder; Electrostatic coating means connected to the guide means, for electrostatically discharging the powder as an adherend therein; Blowing means connected to the electrostatic painting means for providing air blowing at an arbitrary pressure; Rotating means for driving the material to rotate 360 °; And Heat curing means for providing a heat source to the material to cure the powder deposited on the inner diameter Inner diameter coating device of a small diameter pipe comprising a. The method of claim 1, The guide means A connection part connected to the hole of the material; And Inner diameter coating device of a small diameter pipe, characterized in that made of a jig including an extension extending by any slope in the connection portion. The method of claim 1, The guide means An inner diameter coating apparatus for small diameter pipes, characterized in that the jig of the conical section is reduced in cross section toward the hole of the material. The method of claim 2 or 3, An inner diameter coating apparatus for small diameter pipes, wherein the inclination angle of the jig is 3 ° to 8 °. A first step of supplying powder to the electrostatic coating machine through a hopper; Operating a compressor to provide blowing force to the powder nozzle at any pressure; A third step of mounting the material on the rotating device and connecting one side jig to the electrostatic coating device; A fourth step of ejecting the electrostatic powder to one of the jigs provided at both ends of the material having an arbitrary inner diameter from the electrostatic coating machine by using the blowing force; A fifth step of depositing the powder passing through the material on the inner surface by applying power to the material to cause electrostatic powder and (+) and (-) charging, After completing the deposition of the powder on the inner surface of the one side section of the material, the material is rotated 180 ° and the ejection process of the electrostatic powder of the fourth step and the recharging step of the fifth step is characterized in that Inner diameter coating method for small diameter pipes. The method of claim 5, The pressure of the blowing force of the first step is the inner diameter coating method of the small diameter pipe, characterized in that 2 ~ 3 kgf / ㎠ on the basis of the length of the metal pipe is 1m, the inner diameter is 25mm. The method of claim 5, The outer diameter of the metal pipe is made of any one selected from straight, semi-curved, spiral, 90 ° curved, small-diameter pipe, characterized in that the cross section is made of a selected one of the rectangular, polygonal or cross-sectional area is reduced and enlarged. Inner diameter coating method.

Images