KR20190070462A - Enamel Coating Device of Fin Tube for GGH - Google Patents

Abstract

Provided is a fin tube enamel coating apparatus for a GGH of desulfurization equipment, which uniformizes enamel supplied to a coating chamber, protects the enamel coated on the surface of a fin tube from contact with a transfer roll during a transfer process from the coating chamber to a sintering chamber, and uniformizes the coating thickness of the enamel all over the fin tube to provide an enameled fin tube of good quality. According to the present invention, the fin tube enamel coating apparatus comprises: a pretreatment chamber neatly processing a surface of a fin tube transferred simultaneously the rotation of an input conveyor; the coating chamber spraying enamel on a surface of the pretreated fin tube through an enamel nozzle and uniformly coating the enamel with a coating brush; and the sintering chamber sintering the fin tube received after the enamel is coated thereon in a high temperature atmosphere. Moreover, an enamel uniformizing agitator is installed in an enamel tank supplying the enamel to the enamel nozzle, an auxiliary brush in addition to an existing coating brush is installed in the coating chamber, and an hourglass-shaped transfer roll of the coating and sintering chambers is replaced with an embossed transfer roll.

Description

{Enamel Coating Device of Fin Tubes for GGH}

The present invention relates to a fin tube enamel coating apparatus for applying a glaze to the surface of a fin tube for a desulfurization facility GGH and firing the same, and more particularly to a fin tube enamel coating apparatus for homogenizing a glaze, preventing the coating glaze from being damaged due to contact with a transfer roll, The present invention relates to an enamel coating apparatus for a fin tube for a desulfurization equipment GGH, which is emphasized in pursuit of uniform thickness of glaze.

Among the metal tubes, there are fin tubes used for industrial heat exchangers such as power plants that are exposed to long periods of exposure to humid and high-temperature environments. When such a fin tube recovers heat from the exhaust gas containing an acid component, the surface of the fin tube and the heat conductive fins are exposed to the acid dew point as the gas is cooled. As a result, low temperature corrosion phenomenon occurs and durability is lowered, the replacement cycle is short, And economic loss due to lost work due to frequent shutdown.

To cope with this problem, a so-called enamel coating apparatus has been proposed in which a glaze is applied and fired on the entire surface of a fin tube. 10-1474277, 10-1474278 and 10-1074438 are such enamel coating apparatuses.

These prior arts have common features include a feed conveyor that feeds long finned tubes one by one periodically to the pre-treatment chamber, a pretreatment chamber that removes contaminants and oil particles from the surface of the fin tubes and sends them to the coating chamber, A coating chamber in which a glaze is sprayed onto the surface of a glaze spray nozzle and coated with a coating brush uniformly, a firing chamber for firing a fin tube to be brought into the glaze after the glaze is applied, and a fin tube coated with enamel, Conveying conveyor.

If the bubbles remain in the glaze on the surface of the fin tube, the quality of the enamel coating deteriorates. There is also an enamel coating apparatus for removing air bubbles by disposing an air nozzle behind the coating brush to remove air bubbles. If the injection velocity of the compressed air is less than 0.05 m / s, the flow velocity is weak and the bubble removing effect is lower than the expected value. If the injection velocity exceeds 3 m / s, the coated glaze is excessively removed and the enamel coating quality is degraded. Therefore, it is said that the air injection speed is preferably within 0.05 m / s to 3 m / s.

The firing temperature is 750-1000. Enamel coated fin tubes increase heat resistance and acid resistance.

Since glaze has high viscosity, it is impossible to produce high quality coated fin tube as raw solution. Therefore, it is essential to adjust the viscosity so that the spray application is smoothly performed. In other words, it is necessary to maintain the concentration constantly It is also very important.

Conventionally, the glaze adjusted to have an appropriate viscosity is stored in the glaze tank and left until the glaze is exhausted. The glaze is gradually thinned from the lower layer to the upper layer with time as in the case of any mucus. However, if the glaze is left unchanged, it is necessary to change the physical properties, strength and coating thickness of the initial glaze coating layer and the late glaze coating layer. It becomes a point of difficulty.

The feed roll which continuously feeds the fin tube continuously through the whole process ranging from the input, the pre-treatment, the firing, and the unloading is a self-tapping type self-aligning type in which the fin tube is consistently positioned in the middle of the length of the feed roll. . The coating of the glaze must be safely maintained until it is transferred to the pretreatment step but before entering the coating chamber and entering the firing chamber after coating the glaze and initiating firing. To maintain the quality of enamel coated fin tubes.

When a glazed fin tube is rotated and transported on a smooth, long-face-length transport roll, the pin contacts the transport roll in a diagonal direction. The line contact was more frictiony than the needle, and the glaze was scratched and damaged. This is the reason why the defect rate of the coating was high in the fin tube enamel coating apparatus to which the conventional long type conveying roll was applied.

Within the coating chamber, the coating brush is located behind the glaze nozzle, specifically approximately in the middle of the interior of the coating chamber, so that the outer surface of the fin and the outer surface of the tube are coated uniformly by pressing the glaze.

When the pre-treated fin tube enters the coating chamber, the glaze is turned over and the coating is formed to have a uniform thickness by the coating brush. When the coating brush leaves the coating brush, the glaze on the rear surface of the fin tube is scratched by the coating brush, Occasionally, unforeseen cases arise. This is one of the reasons why the enamel quality of the fin tube is inferior.

The above-mentioned prior art fin tube enamel coating apparatus has no means to overcome this phenomenon.

Registration No. 10-1474277 Registration No. 10-1474278 Patent No. 10-1074438

It is an object of the present invention to provide a method and apparatus for homogenizing a glaze supplied to a coating chamber, protecting the glaze coated on the surface of the fin tube from contact with the transfer roll in the course of being transported from the coating chamber to the firing chamber, It is intended to provide an enamel coating apparatus for a fin tube for a desulfurization facility GGH capable of providing a high quality enamel coated fin tube by uniformizing the thickness of the coating.

In order to accomplish the above object, the present invention provides a finishing apparatus comprising: a pretreatment chamber for neatly treating a surface of a finned tube conveyed at the same time as rotation by an inlet conveyor; spraying a glaze onto the surface of the pretreated fin tube with a glaze nozzle, And a firing chamber for firing the fin tube to be brought in after the glaze is coated in a high temperature atmosphere. The present invention relates to a fin tube enamel coating apparatus for coating a glaze with a glaze, And an auxiliary brush is provided in addition to the conventional coating brush in the coating chamber, and a coating method for a fin tube enamel coating apparatus in which a coating chamber and a long type transfer roll of a firing chamber are replaced by an embossing type.

The glaze in the glaze tank is agitated with a stirrer until the glaze is exhausted so that the consistently uniform concentration is maintained.

The secondary brush recoats the glaze on the back end of the fin tube past the coating brush.

The surface of the transfer roll with the embossed finish makes the pins of the pin tube come into point contact, reducing the damage of the glaze on the end of the pin. As the embossing becomes higher, the contact with the pin end portion is small, which is advantageous in preventing glaze damage.

According to the present invention, the glaze in the glaze tank is agitated with a stirrer and uniformly maintained at a uniform concentration, so that the thickness and quality of the glaze coating of the fin tube are fixed, so that a high quality enamel coated fin tube can be obtained.

In addition, the present invention provides for an auxiliary brush installed in the coating chamber to achieve a homogeneous quality of the enamel coating over the entire length of the fin tube by re-coating the surface of the fin tube coated with the glaze with a coating brush, .

In addition, since the contact surface between the fins and the fins is flat, the fins are scratched or transferred to the surface of the fusing roll in the process of being transferred to the firing chamber. The embossing type transfer rolls which have been converted into contact can be provided with enamel coated fin tubes of smooth quality with reduced shrinkage of the glaze on the ends of the pins.

1 is a conceptual view of a fin tube enamel coating apparatus according to the present invention.
2 is a partially cutaway front view of a glaze tank with a stirrer
Fig. 3 shows the relationship between the fin tube and the coating brush
4 is a diagram showing the relationship between the fin tube and the auxiliary brush
Figure 5 is an illustration of an embossed transfer roll

As shown in Fig. 1, the fin tube enamel coating apparatus of the present invention takes in fin tube 2, which is periodically dropped one by one in the tube holder 1, and periodically puts it into the pretreatment chamber A pretreatment chamber 4 for thoroughly removing contaminants such as grease on the surface of the loaded fin tubes 2, a coating chamber 4 for spraying glazes onto the surface of the fin tubes to be introduced, A take-out conveyor 7 for taking out the fired coating tube and taking it out to the outside of the furnace in addition to the firing chamber 6 for heating and baking the glaze-coated fin tube to be brought into the high temperature, a glaze tank 8 ).

The glaze tank 8 is connected to the glaze nozzle 9 by a conduit. The pretreatment chamber 4 removes foreign substances by a known metal surface treatment method such as shot blasting on the surface of the fin tube to be introduced.

As shown in FIG. 2, the glaze tank 8 is provided with a stirrer 20. The glaze should be supplied without interruption while the concentration is maintained, from when the fin tube enamel coating operation is started to the end of enamel coating operation. The stirrer 20 is a built-in type or a detachable type in which the glaze is stirred until the enamel coating operation is completed to maintain the concentration. The detachable type is preferable in view of the cleaning of the inside of the glaze tank 8 and the cleaning of the agitated wool.

As the agitator 20 is equipped in the glaze tank 8, the glaze in the glaze tank 8 can be maintained in the concentration by the agitator 20 and the enamel coating quality of the fin tube can be improved.

1, in addition to the glaze nozzle 9 and the coating brush 10, an auxiliary brush 30 is added in the coating chamber 5. As shown in Fig. The bristles 11 of the coating brush 10 elastically contact the entire surface of the fin tube 2 and uniformly spread the glaze applied on the surface of the fin tube 2 by being sprayed from the glaze nozzle 9. [

3, the bristles 11 are bent in the direction opposite to the direction in which the fin tube 2 is conveyed due to the contact pressure with the fin tube 2. Then, when the rear end of the fin tube 2 is released and the pressure is released, it is resiliently repelled and returned to its original shape, and the glaze on the rear end 2a of the fin tube 2 is smeared. The glaze coating is thinned or peeled off like a nick. It is a factor of poor enamel coating.

As shown in FIG. 4, the auxiliary brush 30 is installed so that the end of the brim 31 is lightly in contact with the end of the fin, unlike the case where the brim 11 is in contact with the entire surface of the fin tube 2, 10) is adjusted so that the glaze grained on the surface of the finned tube 2 is finely spread by soft combing while the glaze collected through the adjustment is applied to the rear end of the fin tube 2, And the thinned portion is glazed to help the coating thickness of the glaze to be uniform throughout the length of the fin tube 2.

The enamel coating quality of the fin tube can be remarkably improved by addition of the auxiliary brush 30.

FIG. 5 illustrates an example of an embossing type transfer roll 40. FIG. The embossing-type transfer roll 40 is formed by forming a small projection 41 on the surface of a long-type transfer roll, or a dimple like a golf ball for projection. The embossing type transfer roll 40 is reduced in contact with the pins of the fin tube compared to the long type transfer roll of a smooth surface.

Therefore, it is possible to improve the enamel coating quality of the fin tube by reducing the damage of the glaze on the pin contacting the transport roll.

1: tube holder
2: Finned tube
3: Feeding conveyor
4: Pretreatment chamber
5: Coating chamber
6: firing chamber
8: Glaze tank
9: Glazing nozzle
10: Coating brush
20: stirrer
30: Secondary brush
31: brushed
40: Embossing type transport roll

Claims (2)

A pretreatment chamber for treating the surface of the fin tube transported while being rotated by the charging conveyor, a glazing nozzle for spraying the glaze of the glaze tank to the surface of the fin tube, and a coating brush for evenly coating the glaze on the surface of the fin tube A fin tube enamel coating apparatus comprising a coated coating chamber, a firing chamber for firing a fin tube to be carried in after the coating of the glaze, and a long-type transfer roll installed so as to reach the discharge from the fin tube,
An agitator for equalizing the concentration of glaze is provided in the glaze tank, an auxiliary brush for glaze application supplementing is installed in the coating chamber in addition to the existing application brush, and a long-sleeved type transfer roll is used as an embossing type transfer roll. Enamel coating device of fin tube.
The enamel coating apparatus according to claim 1, wherein the auxiliary brush is installed such that an end of the brushed portion slightly touches the pin end of the fin tube.

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