KR101740703B1 - Enamel coating device for fin tube and its coating method - Google Patents

Abstract

The present invention relates to an enamel coating apparatus and a coating method for a fin tube, and more particularly, to an enamel coating apparatus for a fin tube for enamelling a fin tube efficiently. According to an aspect of the present invention, there is provided a method of manufacturing a magnetic resonance imaging apparatus including a hollow tube-shaped tube, a transfer unit for transferring a fin tube having a pin formed in a spiral shape on an outer circumferential surface of the tube, A coating unit for coating the glaze powder toward the fin tube charged by the transfer unit; And a heating unit disposed on both sides of the application unit to apply heat to the fin tube, wherein the glaze powder is pure frit. The apparatus for coating an enamel for a fin tube for a short distance which does not deform at a high temperature, to provide.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an enamel coating apparatus for fin tubes,

The present invention relates to an enamel coating apparatus and a coating method for a fin tube, and more particularly, to an enamel coating apparatus and a coating method for a fin tube for enameling a fin tube efficiently.

Generally, a fin tube made of a metal is mainly used in a high temperature and high humidity environment, so a coating for improving durability is required. The enamel coating is one of such coating methods and has an advantage of excellent heat resistance and acid resistance, but it has a disadvantage that a coating process is difficult because a high-temperature calcination is required and a large chamber is required.

Therefore, in the past, researches have been made on a method for solving the above problem and for coating an enamel. For example, Korean Patent Registration No. 0174438 (hereinafter referred to as prior art) discloses an enamel coating method of a metal tube. Specifically, the prior art discloses a technique of pretreating a metal tube, coating it with an enamel glaze, and then firing it.

However, in the case of the enamel glaze in the liquid state disclosed in the above-mentioned prior art, additives such as clay and other oxides must be added inevitably so as not to flow when coating the fin tube. Thus, these additives can cause corrosion problems when the enamel glaze is coated on the fin tube, thereby reducing the acid resistance and easily corroding in environments with high corrosion potential, such as power plants. Further, the additive can make the surface of the fin tube coated with enamel glaze roughened.

In addition, although the prior art has a brush to uniformly apply the enamel glaze, it is possible to uniformly apply the enamel glaze in a liquid state by such a configuration, but it is also possible to adjust the thickness of the enamel coating layer It is impossible. In other words, there is a problem that it is impossible to protect the enamel coating layer by thickening the area where corrosion potential is high.

In addition, since the above-described prior art requires a drying process to form a coating layer in a state in which a liquid enamel glaze is applied, it takes a lot of time to produce fin tubes.

In addition, in the above-mentioned prior art, the enamel glaze is applied to the fin tube, and the roller for conveying the fin tube is also provided in the section where the firing is performed. Therefore, the enamel coated fin tube is frictioned with the roller before the firing is completed. As described above, the outer surface of the fin tube where friction occurs before the firing is peeled off the enamel coating layer, thereby increasing the possibility of corrosion, shortening the operation period, and requiring a lot of replacement and maintenance.

Conventional enamel has a separate process for pre-treatment, sintering, drying, and firing, and it is a process of moving and connecting each process. However, in the case of a fin tube, since the length of the fin tube is long, It has a disadvantage in that it has a large size and a large number of movements per process, and accordingly, many management factors are included in each process.

Korean Patent No. 0174438 (Oct. 11, 2011)

It is an object of the present invention to solve the above problems and provide an enamel coating apparatus and a coating method for fin tubes for enamel coating fin tubes efficiently.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not intended to limit the invention to the precise form disclosed. There will be.

According to an aspect of the present invention, there is provided a method of manufacturing a magnetic resonance imaging apparatus including a hollow tube-shaped tube, a transfer unit for transferring a fin tube having a pin formed in a spiral shape on an outer circumferential surface of the tube, A coating unit for coating the glaze powder toward the fin tube charged by the transfer unit; And a heating unit positioned on both sides of the application unit to apply heat to the fin tube, wherein the glaze powder is a pure frit.

In an embodiment of the present invention, the heating unit may include a preheating unit positioned at one side of the application unit and applying heat to the fin tube charged by the transfer unit; And a firing unit located on the other side of the application unit and applying heat to the fin tube coated with the glaze powder.

In the embodiment of the present invention, the application unit and the preheating unit are spaced apart from each other by a predetermined first interval, and the application unit and the sintering unit are spaced apart from each other by a predetermined second interval, May be different from the second gap.

In an embodiment of the present invention, the first interval may be 0.04 to 0.06 m, and the second interval may be 0.09 to 0.11 m.

In the embodiment of the present invention, the feeder may include: a feeder unit for loading the fin tube into the preheating unit; And an unfeder unit for recovering the fin tube passed through the firing unit.

In the embodiment of the present invention, the feeder unit and the unfederal unit include a plurality of rollers on which the fin tubes are mounted, the first and second wheels being in pairs; A rotating shaft for connecting the center of the plurality of first wheels through; And a motor for providing a rotational power to the rotating shaft, wherein the first wheel is rotated in contact with the outer surface of the pin, thereby moving the pin tube in the forward and backward directions in accordance with the rotating direction of the rotating shaft can do.

According to an embodiment of the present invention, the second wheel supports the fin tube in a rotatable manner, and extends in parallel to the formation direction of the pin formed in a spiral shape.

In the embodiment of the present invention, the distance between the roller provided on the inlet side of the preheating unit and the roller provided on the outlet side of the firing unit is 1 m or more and 1.2 m or less, Thereby preventing deflection of the fin tube.

According to an embodiment of the present invention, the roller may be provided such that a pair of adjacent intervals corresponding to the diameter of the fin tube is adjusted.

In an embodiment of the present invention, the feeder unit further comprises a loader for providing the fin tube on the roller, wherein the unfederal unit further comprises an unloader for retrieving the fin tube located on the roller . ≪ / RTI >

According to another aspect of the present invention, there is provided a method of coating an enamel coating apparatus for a fin tube, comprising the steps of: a) preheating the fin tube; b) applying the glaze powder to the preheated fin tube; And c) firing the fin tube to which the glaze powder is applied. In the step b), the glaze powder is pure frit.

The effect of the present invention according to the above construction is that the glaze powder which is a pure frit in the form of a solid powder is applied to enamel coating on the fin tube, thereby improving the acid resistance of the fin tube.

In addition, the glaze powder is partially fused and adhered to the fin tube preheated by the preheating unit, and the remaining glaze powder is attached to the surface of the fin tube in a powder state. Then, it is completely fused while being charged into the firing unit, and an enamel coating having a very rigid structure is formed.

In addition, the preheating unit removes oil and other impurities existing on the surface of the fin tube, and the enamel layer is formed only by the fine particles by the pure frit, so that the acid resistance is improved and the surface is smooth. It is possible to have better performance than the existing enamel structure.

Further, since the rollers are not provided in the preheating unit, the coating unit, and the baking unit, it is possible to prevent the outer surface of the fin tube, which has not been baked, from being rubbed by the rollers and peeling off the enamel coating layer.

Further, since the heating unit heats the rotating fin tube by using high frequency induction heating, the heat loss is small and the heat loss is small as compared with the conventional electric heating method.

Further, the fin tube is heat-treated twice by the preheating unit and the baking unit, and the elongation is improved.

Further, an air curtain is provided at the outlet of the application portion, and the problem that the glaze powder applied in the application portion is discharged together with the fin tube to the outlet can be prevented.

Further, the recovery unit provided in the application unit is economical by allowing the applied glaze powder not fused to the fin tube to be recycled.

It should be understood that the effects of the present invention are not limited to the above effects and include all effects that can be deduced from the detailed description of the present invention or the configuration of the invention described in the claims.

1 is a side view of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
FIG. 2 is a top view illustrating a transfer portion of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
3 is an exemplary view of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
4 is an exemplary view showing a heating chamber of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
5 is an exemplary view showing an application portion of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
6 (a) is a photograph showing a fin tube before enamel coating by an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
6 (b) is a photograph showing an enamel coated fin tube by an enamel coating apparatus for a fin tube according to an embodiment of the present invention.
7 is a flowchart showing a coating method of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" (connected, connected, coupled) with another part, it is not only the case where it is "directly connected" "Is included. Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

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

FIG. 1 is a side view of an enamel coating apparatus for a fin tube according to an embodiment of the present invention, and FIG. 2 is a top view illustrating a transferring unit of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.

1 and 2, the enamel coating apparatus 1000 for a fin tube includes a transfer section 1100, a heating section 1200, and a dispensing section 1300. The transfer unit 1100 is provided to transfer the fin tube 10 and the heating unit 1200 is disposed on both sides of the application unit 1300 to heat the fin tube 10, And includes a preheating unit 1210 and a firing unit 1220. The application unit 1300 is provided to apply the glaze powder to the fin tube 10 charged by the transfer unit 1100. Here, the fin tube 10 has a hollow tube-shaped tube 11 and a pin 12 formed in a spiral shape on the outer peripheral surface of the tube 11.

Hereinafter, each configuration of the enamel coating apparatus 1000 for fin tubes will be described in more detail.

First, the feeding unit 1100 includes a feeder unit 1110 and an unfeeder unit 1120.

The feeder unit 1110 can load the fin tube 10 into the preheating unit 1210 and includes a roller 1111, a motor 1114, and a rotating shaft 1115.

The roller 1111 includes a first wheel 1112 and a second wheel 1113. The first wheel 1112 and the second wheel 1113 form a pair, (10). The plurality of rollers 1111 may be provided.

The rotating shaft 1115 may be connected to the center of the plurality of first wheels 1112.

The motor 1114 may provide rotational power to the first wheel 1112 by rotating the rotational shaft 1115.

The first wheel 1112 is rotated in contact with the outer surface of the pin 12 so that the pinion tube 10 is rotated in the direction in which the motor 1114 rotates the rotation shaft 1115. [ Can be moved in the forward and backward directions. For example, when the motor 1114 rotates the rotation shaft 1115 in the clockwise direction, the first wheel 1112 rotates clockwise in the counterclockwise direction with respect to the pin tube 10 having the spiral fin 12, And can be moved forward. Conversely, when the first wheel 1112 is rotated counterclockwise by the motor 1114, the pin tube 10 can be moved backward while rotating clockwise.

The second wheel 1113 is provided so as to rotatably support the fin tube 10 while being in contact with the outer surface of the fin tube 10, May be formed so as to extend in parallel to the forming direction of the substrate (12). The second wheel 1113 thus provided can prevent the pin tube 10 from being separated from the roller 1111 or idle.

Further, the roller 1111 may be provided such that a pair of adjacent intervals corresponding to the diameter of the fin tube 10 is adjusted. Specifically, the roller 1111 may be formed such that the interval between the first wheel 1112 and the second wheel 1113 forming the pair is changed according to the diameter of the fin tube 10. Therefore, the enamel coating apparatus 1000 for a fin tube can adjust the interval between the first wheel 1112 and the second wheel 1113 to correspond to many kinds of fin tubes having various diameters such as 38 mm to 75 mm Therefore, the enamel coating for the fin tube 10 having various diameters can be efficiently and economically performed.

The unfuser unit 1120 may be provided to recover the fin tube 10 that has passed through the firing unit 1220. The unfuser unit 1120 is provided downstream of the firing unit 1220 and includes a roller 1121 and a motor 1124 to move the fin tube 10 passed through the firing unit 1220 in the forward and backward directions. And a rotating shaft 1125. [ The roller 1121 includes a first wheel 1122 and a second wheel (not shown). The detailed configuration of the unfederal unit 1120 is substantially the same as the detailed configuration of the feeder unit 1110, and a detailed description thereof will be omitted.

The roller 1111 of the feeder unit 1110 provided at the inlet side of the preheating unit 1210 and the roller 1121 of the unfeeder unit 1120 provided at the outlet side of the firing unit 1220 Is formed to be equal to or greater than 1 m and equal to or less than 1.2 m so as to prevent the pin tube 10 located in the heating unit 1200 and the applying unit 1300 from sagging.

More specifically, the heated fin tube 10 is relatively weak in rigidity as it passes through the heating unit 1200 at a high temperature. Therefore, when the distance between the roller 1111 of the feeder unit 1110 supporting the lower portion of the fin tube 10 and the roller 1121 of the unfederal unit 1120 exceeds 1.2 m, Deflection occurs in the fin tube 10, and bending deformation may occur. The gap between the roller 1111 of the feeder unit 1110 and the roller 1121 of the unfeeder unit 1120 may be positioned between the heating unit 1200 and the application unit 1300, It is preferable that the fin tube 10 is formed to be 1.2 m or less so as not to cause sag in the fin tube 10.

Since the rollers are not located in the heating unit 1200 and the application unit 1300, the outer surface of the fin tube 10, which is not yet fired, is rubbed by the rollers to peel off the enamel coating layer .

The feeder unit 1110 further includes a loader (not shown) for providing the fin tube 10 on the roller 1111 and the unfeder unit 1120 is disposed on the roller 1111, And an unloader (not shown) for recovering the fin tube 10.

FIG. 3 is an exemplary view of an enamel coating apparatus for a fin tube according to an embodiment of the present invention, and FIG. 4 is an exemplary view illustrating a heating chamber of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.

As shown in Figs. 3 and 4, the heating unit 1200 includes a preheating unit 1210, a firing unit 1220, and the like.

The preheating unit 1210 is located at one side of the application unit 1300 and can apply heat to the fin tube 10 charged by the transfer unit 1100. The firing unit 1220 is located on the other side of the application unit 1300 and can apply heat to the fin tube 10 coated with the glaze powder.

The application unit 1300 and the firing unit 1220 are spaced apart from each other by a predetermined first interval and the firing unit 1220 is spaced apart from the application unit 1300 by a predetermined second interval And the first interval is narrower than the second interval. Specifically, the fin tube 10 is heated to a temperature of 800 ° C or higher and 860 ° C or lower in order to achieve a high-quality enamel coating when the fin tube 10 is charged into the application unit 1300 through the preheating unit 1210 State. That is, the fin tube 10 that has passed through the preheating unit 1210 needs to be quickly cooled into the inside of the application unit 1300 before being cooled by heat. Accordingly, the first gap may be formed to be narrower than the second gap, so that the fin tube 10 having passed through the preheating unit 1210 can be quickly charged into the applying unit 1300. Preferably, the first interval is 0.04 to 0.06 m, and the second interval is 0.09 to 0.11 m. The length from the end of the preheating unit 1210 to the end of the firing unit 1220 may be less than 1.2 m.

The preheating unit 1210 and the firing unit 1220 can be induction-heated by movement of the fin tube 10 in a high frequency magnetic field. Specifically, the high frequency induction heating utilizes the principle that an eddy current is generated which interferes with the change of the magnetic field when the magnetic field applied to the metal conductor inside the magnetic field is changed. The eddy current is a current that is resistant to changes in the magnetic field, which interferes with the movement of the metallic conductor moving within the magnetic field, and the metal conductor is heated as the eddy current is lost.

Since the heating unit 1200 heats the fin tube 10 through the high-frequency induction heating of the above-described principle, there is an advantage that the heat loss is small and the lenticularity is small as compared with the conventional electric heating system. Specifically, since the heating unit 1200 is heated from the inside of the fin tube 10 to be rotated and transferred, the laminating gap is small, and the bonding structure of the enamel coating is further strengthened. The eddy current is generated only when the metal conductor moves inside the magnetic field to change the magnetic field applied to the metal conductor. Therefore, only when the fin tube 10 is located inside the preheating unit 1210 or the firing unit 1220, the fin tube 10 is heated while being rotated, and other power is not used. As a result, the operation energy and operation cost of the heating unit 1200 are reduced, and safe and efficient operation is possible.

The heating unit 1200 can heat the fin tube 10 to 800 ° C to 860 ° C.

Specifically, the preheating unit 1210 may include a heating chamber 1211 and a heating module 1214.

4 (a) is an exemplary view showing a heating chamber according to the first embodiment.

4A, the heating chamber 1211a according to the first embodiment forms the body of the preheating unit 1210 and includes a first vertical frame 1212a and a first horizontal frame 1213a .

The first vertical frame 1212a is located at one side of the fin tube 10 and may extend vertically from the ground. The first horizontal frame 1213a may extend parallel to the upper and lower ends of the fin tube 10 from the upper and lower ends of the first vertical frame 1212a, respectively.

4 (b) is an exemplary view showing a heating chamber according to the second embodiment.

4B, the heating chamber 1211b according to the second embodiment forms the body of the preheating unit 1210, and the second vertical frame 1212b and the second horizontal frame 1213b form a body of the preheating unit 1210. [ .

The second vertical frame 1212b is located at one side of the fin tube 10 and may extend vertically from the ground. The second horizontal frame 1213b extends from the upper end and the lower end of the second vertical frame 1212b toward the upper and lower ends of the fin tube 10, And may be curved so as to have a curvature corresponding to the circumference of the fin tube 10, as shown in FIG. The second vertical frame 1212b thus provided can reduce the thermal deviation of the fin tube 10 and reduce the leakage of heat to the outside, thereby increasing the thermal efficiency.

FIG. 4C is an exemplary view showing a heating chamber according to the third embodiment. FIG.

As shown in FIG. 4C, the heating chamber 1211c according to the third embodiment may be provided in a tube shape in which the fin tube 10 can be received therein. The heating chamber 1211c thus provided can further prevent the heat applied to the fin tube 10 from flowing to the outside, thereby improving the thermal efficiency.

The heating module 1214 may be provided in the heating chambers 1211a, 1211b, and 1213c described in the first to third embodiments. The heating module 1214 may form a high frequency magnetic field so that the fin tube 10 is induction heated as the fin tube 10 moves in the high frequency magnetic field.

The firing unit 1220 may perform firing heating on the enamel coated fin tube 10 through the application unit 1200. The firing unit 1220 includes the heating chamber 1221 and a heating module (not shown). The heating chamber 1221 of the firing unit 1220 and the heating module are substantially the same in configuration as the preheating unit 1210, so a detailed description of the configuration will be omitted.

The firing unit 1220 can completely fuse the glaze powder attached to the surface of the fin tube 10 in a powder state to the fin tube 10. Specifically, when the glaze powder is applied to the fin tube 10, a part of the glaze powder is immediately fused to the fin tube 10, and the remaining powder is attached to the surface of the fin tube 10 in powder form. Therefore, the firing unit 1220 can completely fuse the glaze powder, which is attached to the surface of the fin tube 10 in powder form, to the fin tube 10, so that a firm enamel coating can be performed

The heating unit 1200 may further include a sensor unit 1230 and a control unit 1240.

The sensor unit 1230 includes a first sensor 1231 located on the downstream side of the preheating unit 1210 and a second sensor 1232 located on the downstream side of the firing unit 1220, The temperature of the tube 10 can be measured. However, the position of the sensor unit 1230 is not limited to the embodiment, and the first sensor 1231 can measure the temperature of the fin tube 10 passing through the preheating unit 1210, The second sensor 1232 may be included in an embodiment as long as it can measure the temperature of the fin tube 10 passing through the firing unit 1220.

The control unit 1240 controls the temperature of the fin tube 10 so that the temperature of the fin tube 10 is heated to a predetermined temperature when the temperature of the fin tube 10 measured by the sensor unit 1230 is out of a predetermined temperature. The heating module 1214 of the preheating unit 1210 and the heating module of the firing unit 1220 can be controlled.

For example, when the temperature of the fin tube 10 measured by the first sensor 1231 is less than 800 ° C, the control unit 1240 increases the intensity of the magnetic field of the heating module 1214, It is possible to control the temperature of the evaporator 10 to be high. When the temperature of the fin tube 10 measured by the first sensor 1231 exceeds 850 ° C, the control unit 1240 decreases the intensity of the magnetic field of the heating module 1214, It is possible to control the temperature of the evaporator 10 to be high.

The control unit 1240 may further be connected to the transfer unit 1100 and the control unit 1240 may control the temperature of the fin tube 10 measured by the first sensor 1231 The motor 1114 of the feeder unit 1110 rotates the roller 1111 in the opposite direction so that the fin tube 10 reaches a predetermined temperature, And then recharged to the heating chamber 1211. For example, when the temperature of the fin tube 10 measured by the first sensor 1231 is less than 800 ° C, the control unit 1240 rotates the roller 1111 in the opposite direction, 10 may be recharged into the heating chamber 1211. The control unit 1240 causes the roller 1111 to rotate in the opposite direction again when the fin tube 10 is heated to 800 ° C or higher to load the fin tube 10 into the application portion 1300 .

The control unit 1240 may be installed in the application unit 1300 when the temperature of the fin tube 10 is 800 ° C or higher and 860 ° C or lower, The glaze powder may be enamelled by the glaze powder.

As described above, the fin tube 10 may be heated twice by the preheating unit 1210 and the firing unit 1220 to improve the elongation.

Fin tube heating stage Fin tube Elongation (%)
Before preheating unit
Experimental Example 1 32 Experimental Example 2 28 Experimental Example 3 32
After passing the preheating unit
Experimental Example 4 37 Experimental Example 5 36 Experimental Example 6 34
After passing the firing unit
Experimental Example 7 37 Experimental Example 8 38 Experimental Example 9 37

Table 1 shows the elongation ratios of the fin tubes 10 according to the heating step. Specifically, the Experimental Examples 1 to 3 are the fin tube 10 before passing through the preheating unit 1210, and the elongation of the fin tube 10 is found to be 28% to 32% have.

Experimental Examples 4 to 6 show the fin tube 10 after passing through the preheating unit 1210. At this time, it can be seen that the elongation of the fin tube 10 is increased from 34% to 37%.

Experimental Examples 7 to 9 are the fin tube 10 after passing through the firing unit 1220. It can be seen that the elongation of the fin tube 10 is increased from 37% to 38% at this time.

As can be seen in Table 1, the fin tube 10 can be increased in elongation through the preheating unit 1210 and the firing unit 1220.

5 is an exemplary view showing an application portion of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.

1 and 5, the application unit 1300 is provided to apply the glaze powder to the fin tube 10, and includes a coating chamber unit 1310 and a spray unit 1320.

The coating chamber unit 1310 is provided to allow the fin tube 10 to pass therethrough and constitute a body forming the outer shape of the application unit 1300. The coating chamber unit 1310 may be made of a material having heat resistance so as not to be damaged by the fin tube 10 in a heated state. Specifically, when the fin tube 10 is charged into the application chamber unit 1310, the fin tube 10 has a high temperature of 800 ° C to 860 ° C. Therefore, it is preferable that the coating chamber unit 1310 is formed of a material having heat resistance that does not cause damage at a temperature of at least 860 ° C.

1, the coating chamber unit 1310 may be formed with an air curtain 1351 at an outlet through which the fin tube 10 passes. The air curtain 1351 can prevent the glaze powder from flowing out of the application chamber unit 1310 through the outlet.

Specifically, the fin tube 10 is charged into the inlet of the application chamber unit 1310 and passes through the outlet. At this time, as the fin tube 10 passes through the outlet of the application chamber unit 1310, the glaze powder existing inside the application chamber unit 1310 flows into the application chamber unit 1310 together with the fin tube 10 1310). ≪ / RTI > Therefore, the air curtain 1351 is provided at the outlet side of the application chamber unit 1310, thereby preventing the glaze powder from flowing out to the outlet side of the application chamber unit 1310.

Meanwhile, since the fin tube 10 is continuously charged at the inlet of the application chamber unit 1310, a flow of air is generated from the outside of the application chamber unit 1310 toward the inside thereof. That is, it is preferable that the air curtain 1351 is not installed at the inlet side of the application chamber unit 1310 because the glaze powder is not discharged to the outside through the inlet.

Since the temperature of the fin tube 10 in a heated state may be lowered when the air curtain 1351 is provided on the inlet side of the coating chamber unit 1310, It is preferable that the air curtain 1351 is not provided on the inlet side.

The spray unit 1320 is installed on the upper side of the application chamber unit 1310 and is capable of applying the glaze powder to the fin tube 10 in a heated state. Here, the glaze powder may be a pure frit. Specifically, the glaze powder is in the form of a solid powder composed of pure frit, and does not include an enamel additive such as clay or other oxides. As described above, since the application portion 1300 applies enamel coating to the fin tube 10 by applying the glaze powder which is pure frit in the form of solid powder, the acid resistance of the fin tube 10 can be improved.

When the pure frit powder is fused to the heated fin tube 10 and enamelled, the impurities existing on the surface of the fin tube 10 are heated to 800 ° C or higher by 860 ° C Deg.] C or lower. Therefore, the fin tube 10 coated with enamel is further improved in acid resistance, and the surface can be smoothed.

The installation position of the injection unit 1320 is not limited to that provided on the upper side of the application chamber unit 1310 and may be provided on the side of the application chamber unit 1310. [ That is, the injection unit 1320 can be installed at a position where the pure frit powder can be uniformly applied to the fin tube 10.

The thickness of the enamel coating layer of the fin tube 10 may vary depending on the preheating temperature of the fin tube 10. Specifically, the higher the temperature at which the fin tube 10 is charged into the application chamber unit 1310, the thicker the enamel coating layer of the fin tube 10 becomes. On the other hand, as the temperature when the fin tube 10 is charged into the application chamber unit 1310 is lower, the thickness of the enamel coating layer of the fin tube 10 becomes thinner.

The application unit 1300 may further include a storage unit 1330, a collection unit 1340, and a discharge unit 1350.

First, the storage unit 1330 stores the pure frit glaze powder, and may provide the stored pure frit glaze powder to the injection unit 1320. The storage unit 1330 may be located on the upper side of the application chamber unit 1310 or may be located on the upper side of the application chamber unit 1310. However, And all the positions that can be supplied.

The recovery unit 1340 recovers residual glaze powder not coated on the fin tube 10 among the pure prilled glaze powders applied from the injection unit 1320 and moves the glaze powder to the injection unit 1320 . The collecting unit 1340 includes a collecting container 1341 and a pump 1342.

The collection container 1341 may be provided below the application chamber unit 1310 to collect the residual glaze powder. Specifically, when the spray unit 1320 applies the pure frit powder to the heated fin tube 10, a part of the applied pure frit powder is fused to the fin tube 10, It can be used as a material. On the other hand, the remaining pure frit glaze powder not fused to the fin tube 10 is accumulated on the lower side of the application chamber unit 1310. Therefore, the collecting container 1341 can collect the residual glaze powder accumulated on the bottom surface of the application chamber unit 1310. As shown in FIG. 5, the application chamber unit 1310 may be provided in a reverse trapezoidal shape so that the residual glaze powder is collected in the collection container 1341.

The pump 1342 can move the residual glaze powder collected in the collecting container 1341 to the injection unit 1320. When the residual glaze powder that is not used for the enamel coating is accumulated on the lower side of the application chamber unit 1310, it is troublesome to periodically open and clean the application chamber unit 1310, There is a problem in that the operation of the coating apparatus 1000 must be stopped for the time for cleaning the remaining glaze powder. However, since the pump 1342 thus provided continuously moves the residual glaze powder collected in the collecting container 1341 to the spraying unit 1320, it is possible to recycle the residual glaze powder that has been sprayed, It is also possible to extend the operating time of the enamel coating apparatus 1000 for tubes to perform an economical enamel coating operation.

Also, the pump 1342 may supply the residual glaze powder collected in the collecting container 1341 to the storing unit 1330.

Further, a separate control module (not shown) for interlocking the collection unit 1340 and the storage unit 1330 may be provided. The control module may control the amount of the pure frit powder to be supplied to the spray unit 1320 by the storage unit 1330 according to the amount of residual glaze powder supplied to the spray unit 1320 by the collection unit 1340. [ As shown in FIG.

The discharge unit 1350 is provided at one side of the application chamber unit 13100 and can discharge the air inside the application chamber unit 1310. The discharge unit 1350 includes a discharge body 1351, A filter 1352, and a scrubber 1353.

The discharge body 1351 may be provided in a tubular shape on one side of the application chamber unit 1310. Specifically, the discharge body 1351 may be provided on one side of the application chamber unit, and may extend upward. When the pure frit powder is enamel-coated on the fin tube 10 through the inside of the discharge body 1351, fine glaze powders and harmful substances contained in the air generated and discharged can be discharged.

The filter 1352 is provided inside the discharge body 1351 and the filter 1352 can collect fine glaze powder and harmful substances contained in the air discharged to the outside through the discharge body 1351 have.

The scrubber 1353 may recover excess fine glaze powder and toxic substances contained in air discharged from the discharge body 1351. That is, the scrubber 1353 can safely operate the enamel coating apparatus 1000 for a fin tube by recovering fine glaze powder and harmful substances that are not collected through the filter 1352.

The enamel coating apparatus 1000 for a fin tube as described above does not need an additional apparatus for uniformly applying the pure frit powder like a brush. Since the pure enamel coating apparatus 1000 for a fin tube uses solid pure glaze powder, a drying apparatus for drying a conventional liquid enamel glaze is not needed, The installation area is further reduced.

In addition, the enamel coating apparatus 1000 for a fin tube has been subjected to a process of applying all the heat in a minimum length range that can be thermally deformed, though the length of the apparatus is short. Since the glaze powder to be used is not only a pure frit but also has a small particle size and no moisture content, the surface of the fin tube 10 is untreated due to the surface tension, or the pin hole It is possible to minimize the adherence caused by the limestone-like materials generated in the use environment.

In addition, the enamel coating apparatus 1000 for a fin tube may be configured such that the pure pretreatment is applied to the annealing unit 1000 after the annealing unit 1210 is thermally treated at a temperature of 800 ° C or higher rather than 500-550 ° C. As a measure for the occurrence of defects such as scale or chipping of the enamel surface due to the influence of gas ejection or the like which may occur in the structure in which the interior of the fin tube 10 is not enameled, It can also have the effect of fusing the enamel layer more firmly than the pin.

6 (a) is a photograph showing a fin tube before enamel coating by an enamel coating apparatus for a fin tube according to an embodiment of the present invention, and FIG. 6 (b) This is a photograph showing an enamel coated fin tube by an enamel coating apparatus for a tube.

7 is a flowchart showing a coating method of an enamel coating apparatus for a fin tube according to an embodiment of the present invention.

As shown in Fig. 7, the coating method of the enamel coating apparatus for a fin tube may first be performed (S10) of preheating the fin tube 10. In this step, the fin tube 10 may be pre-heated by high-frequency induction heating at 800 ° C or higher and 860 ° C or lower, and may be preheated to correspond to the thickness of the enamel coating layer to be formed on the fin tube 10. More specifically, when the temperature of the fin tube 10 is higher and the glaze powder is applied, the enamel coating layer is formed thicker. Therefore, the preheating temperature of the fin tube 10 can be determined in consideration of the thickness of the enamel coating layer to be formed on the fin tube 10. In step S10 of preheating the fin tube 10, enamel coating can be more easily accomplished by burning and removing foreign matter such as oil on the surface of the fin tube 10.

Next, step (S20) of applying the glaze powder to the preheated fin tube 10 may be performed. Here, the glaze powder may be pure frit.

Next, step (S30) of firing the fin tube 10 coated with the glaze powder may be performed. Specifically, when the fin tube 10 is pre-heated and the powder is applied to the fin tube 10, only a part of the powder of the glaze attached to the fin tube 10 is fused, It is possible to pass through the application portion 1300 in a state in which the fin tube 10 is not fused and attached. Therefore, the step (S30) of firing the fin tube 10 coated with the glaze powder may be performed by completely fusing the glaze powder remaining in the attached state without fusion to the fin tube 10 So that the enamel coating can be more firmly formed. Also in this step, the fin tube 10 can be heated by high frequency induction heating.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

10: pin tube 11: tube
12: pin
1000: Enamel coating device for fin tube 1100:
1110: feeder unit 1111: roller
1112: first wheel 1113: second wheel
1114: motor 1115:
1120: Unfuser unit 1121: Roller
1122: first wheel 1124: motor
1125: rotating shaft 1200: heating part
1210: Preheating unit 1211: Heating chamber
1211a: first heating chamber 1211b: second heating chamber
1211c: third heating chamber 1212a: first vertical frame
1212b: second vertical frame 1213a: first horizontal frame
1213b: second horizontal frame 1214: heating module
1220: firing unit 1221: heating chamber
1230: sensor unit 1231: first sensor
1232: second sensor 1240: control unit
1300: dispensing part 1310: dispensing chamber unit
1311: Air curtain 1320: Discharging unit
1330: storage unit 1340: collection unit
1341: collection container 1342: pump
1350: exhaust unit 1351: exhaust body
1352: Filter 1353: Scrubber

Claims (11)

A transfer tube for transferring a tube having a hollow tube shape and a fin tube having a pin formed in a spiral shape on an outer circumferential surface of the tube;
A coating unit for coating the glaze powder toward the fin tube charged by the transfer unit; And
And a heating unit located on both sides of the application unit to apply heat to the fin tubes,
The heating unit includes:
A preheating unit located at one side of the application unit and applying heat to the fin tube charged by the transfer unit;
A firing unit located on the other side of the application unit and applying heat to the fin tube coated with the glaze powder;
A sensor unit having a first sensor located on the downstream side of the preheating unit and a second sensor located on the downstream side of the preheating unit; And
A control unit,
Wherein the preheating unit and the baking unit further comprise a heating module for forming the high frequency magnetic field so that the fin tube is induction heated as it is moved in a high frequency magnetic field,
Wherein the control unit controls the heating module so that the temperature of the fin tube is heated to a predetermined temperature when the temperature of the fin tube measured by the sensor unit is out of a predetermined temperature,
Wherein the glaze powder is a pure frit.
delete The method according to claim 1,
Wherein the application unit and the preheating unit are spaced apart from each other by a predetermined first interval, the application unit and the firing unit are spaced apart from each other by a predetermined second interval, and the first interval is different from the second interval Features enamel coating device for finned tube .. The method of claim 3,
Wherein the first gap is 0.04 to 0.06 m, and the second gap is 0.09 to 0.11 m. The method according to claim 1,
The transfer unit
A feeder unit for feeding the fin tube into the preheating unit; And
And an unfeder unit for recovering a fin tube that has passed through the firing unit. 6. The method of claim 5,
Wherein the feeder unit and the unfederal unit are arranged so that,
A plurality of rollers on which the fin tubes are seated on an upper side and in which a first wheel and a second wheel form a pair;
A rotating shaft for connecting the center of the plurality of first wheels through; And
And a motor for providing rotational power to the rotating shaft,
Wherein the first wheel is rotated in contact with the outer surface of the fin to move the fin tube in the forward and backward direction in accordance with the rotating direction of the rotating shaft. The method according to claim 6,
The second wheel,
Wherein the fin tube is rotatably supported and extends in parallel to a forming direction of the pin formed in a spiral shape. The method according to claim 6,
The distance between the roller provided at the inlet side of the preheating unit and the roller provided at the outlet side of the firing unit is set to 1 m or more and 1.2 m or less to prevent deflection of the fin tube located in the heating unit and the application unit Wherein the enamel coating apparatus for a fin tube comprises: The method according to claim 6,
The roller
And a pair of adjacent pair of the fin tubes are provided so as to correspond to diameters of the fin tubes. The method according to claim 6,
Wherein the feeder unit further comprises a loader for providing the fin tube on the roller,
Wherein the unfeder unit further comprises an unloader for recovering the fin tube positioned on the roller. A method for coating an enamel coating apparatus for a fin tube according to any one of claims 1 to 10,
a) preheating the fin tube;
b) applying the glaze powder to the preheated fin tube; And
c) firing the fin tube to which the glaze powder is applied,
Wherein the glaze powder is pure frit in the step b).

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