JP4956886B2 - Pre-painting method and apparatus for strip-shaped body - Google Patents

Description

The present invention relates to a belt pre- coating method and apparatus for applying a coating material continuously to a surface of a belt such as a steel plate while traveling.

A reverse coater is widely used as a coating apparatus. However, since coating unevenness is likely to occur when coating is performed at a high speed, there is a method of performing preliminary coating to prevent this coating unevenness. As the preliminary coating, there is a method of spraying paint on the plate surface using a spray nozzle (see, for example, Patent Document 1).
Furthermore, in such coating with a spray nozzle, a plurality of nozzle holes are formed in the width direction of the band-shaped body, an edge mask is provided at a position facing the side edge of the band-shaped body, and the position of the edge mask is adjusted, There is one that closes the nozzle hole as appropriate (Patent Document 2). This prevents the paint from getting around and running out of liquid when the plate width changes suddenly or when the plate meanders.
JP-A-2-59058 Japanese Patent No. 2823956

However, it is difficult to adjust the position of the edge mask in accordance with a rapid change in the plate width or the meandering of the plate. Because of this, the adjustment of the position of the edge mask cannot catch up, and if the nozzle hole is not sufficiently closed, the coating will wrap around, while the nozzle hole is blocked more than necessary, The paint will run out.
The present invention has been made in view of the above problems, and in the case of coating a strip with a spray nozzle, the coating method and the apparatus for the strip that can prevent the coating from wrapping around and the liquid running out with a simple structure. For the purpose of provision.

Preliminary coating method according to the invention of claim 1 strip description is continuously in strip running a pre-coating method of the strip subjected to coating, at a position opposed to the strip, of the strip Provided as a rectangular slit shape extending in the width direction and shorter than the width of the belt-like body, spraying paint from a paint spraying port provided with a lip composed of a pair of brushes extending in parallel across the slit; and The lip is brought into contact with the strip and the paint is applied to the strip.
Also, pre-coating method of the strip according to the invention of claim 2, wherein, in the preliminary coating method of the strip according to the first aspect of the invention, is a strip of various widths intended to be coated body, The length in the width direction of the belt-like body of the paint spray port is shorter than the minimum width among the various widths.

Also, pre-coating apparatus of the strip according to the third aspect of the present invention, a pre-coating apparatus of the strip subjected to continuously painted strip traveling, the equalizing chamber for introducing the coating material, the average The pressure chamber has a rectangular slit shape that extends in the width direction of the belt-like body and is shorter than the width of the belt-like body, sandwiches the paint jet port for spraying the paint in the pressure equalizing chamber, and And a lip made of a pair of brushes that are arranged along the paint injection port and extend in parallel with the opening direction of the paint injection port and are brought into contact with the belt-like body.
Also, pre-coating apparatus of the strip according to the invention of claim 4, wherein, in the preliminary coating apparatus of the strip according to the invention of claim 3 wherein is a strip of various widths intended to be coated body, The length in the width direction of the belt-like body of the paint spray port is shorter than the minimum width among the various widths.

According to the present invention, the paint injection port for applying the paint to the belt-like body has a simple structure such as a rectangular slit shape extending in the width direction of the belt-like body and shorter than the width of the belt-like body. , Can prevent the paint from running around and running out of liquid.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings.
This embodiment is a coating apparatus to which the present invention is applied. 1 and 2 show the configuration of the coating apparatus. 1 is a cross-sectional view of the coating apparatus as seen from the front, and FIG. 2 is a cross-sectional view as seen from the arrow AA in FIG.
1 and 2, reference numeral 1 is a pressure equalizing chamber, reference numeral 2 is an introduction pipe for introducing paint into the pressure equalizing chamber 1, and reference numeral 3 is a width direction of a strip-like body 100 such as a steel strip to be passed through. , And 4a and 4b are a pair of lips provided along the paint spraying port 3 with the paint spraying port 3 interposed therebetween. .

FIG. 3 is a view of the belt-like body 100 as viewed from above. As shown also in FIG. 3, the coating material injection port 3 positioned facing the surface of the belt-like body 100 has a rectangular slit shape, and the length of the belt-like body 100 in the width direction is the width of the belt-like body 100. Is shorter. Here, if the strips of various widths are to be passed through the coating apparatus, the length in the width direction of the strips of the paint injection port 3 is shorter than the narrowest of the various widths. ing.
The lips 4a and 4b are made of brushes extending in parallel with the opening direction of the paint spraying port 3, that is, the spraying direction of the paint from the paint spraying port 3. Both the lips 4a and 4b may be brushes, but at least the lip disposed on the downstream side in the plate passing direction of the belt-like body 100 may be used as a brush. The lip is not limited to a brush, and any other material can be used as long as it is a material into which a paint such as other sponges soaks.

  By the coating apparatus having the above-described configuration, the coating material is sprayed from the coating material spraying port 3 and applied to the surface of the belt-shaped body 100. At this time, the paint sprayed from the paint spraying port 3 flows along the surface of the belt-like body 100, that is, a flow parallel to the band width direction of the belt-like body 100. As a result, the coating material can be applied to the surface of the belt-like body 100 without wrapping around the coating material or running out of liquid.

  For example, in the technique described in Patent Document 2, since the paint is sprayed from the single hole-shaped nozzle hole, the same flow rate as that of the paint sprayed from the slit-shaped paint spray port as in this embodiment is used. When the paint is to be sprayed, the spraying speed of the paint from the nozzle hole is increased. Therefore, the spraying flow rate of the paint from the nozzle hole located near the end of the belt-like body is also large without exception. For this reason, it is necessary to finely adjust the position of the edge mask in order to prevent the paint from flowing around and running out of liquid. It can be said that it is difficult to prevent clogging and running out of liquid.

On the other hand, in the present embodiment, since the coating material injection port 3 has a large-diameter slit shape, it is possible to realize coating with a desired film thickness while suppressing the spraying flow rate of the coating material. The flow of the paint sprayed from the spray port 3 becomes a flow parallel to the band width direction of the band-shaped body 100 as indicated by an arrow B shown in FIG. Thereby, the coating material can be applied to the surface of the belt-like body 100 without wrapping around the coating material or running out of liquid. As a result, it is possible to prevent the coating material from flowing around or running out of liquid even when the plate width changes suddenly or the plate meanders.
Further, the paint sprayed between the lip 4a and 4b from the paint spraying port rises through a small gap of the brush, which is the lip 4a and 4b, and is uniformly supplied to the surface of the belt-like body 100 that contacts the brush.

FIG. 5 shows a continuous coating apparatus (continuous coating facility) provided with the above-described coating apparatus as the preliminary coating apparatus 11.
In the continuous coating apparatus shown in FIG. 5, the pick-up roll 13, the metering roll 14 and the applicator roll 16 constitute a so-called roll coater.
In this continuous coating apparatus, the paint 200 is stored in the paint pan 12, and the paint 200 is scraped up onto the peripheral surface of the pickup roll 13 by the rotation of the pickup roll 13 brought into contact with the bath of the paint pan 12. Then, the paint 200 is measured so as to have a desired film thickness by passing through a predetermined gap set between the pickup roll 13 and the metering roll 14. The paint adhering to the surface of the metering roll 14 after the measurement is removed by the scraper 15.

The measured paint 200 is transferred from the surface of the pick-up roll 13 to the surface of the applicator roll 16, and then, from the applicator roll 16 to the surface of the band-shaped body 100 at the contact portion of the applicator roll 16 with the band-shaped body 100. Is transcribed.
The coating apparatus shown in FIGS. 1 and 2 is arranged as the preliminary coating apparatus 11 on the front stage side where the coating material is transferred to the strip 100 by the roll coater described above. In the preliminary coating apparatus 11, paint is supplied from the pump 17 to the pressure equalizing chamber 1 through the introduction pipe 2, and the paint supplied to the pressure equalizing chamber 1 is sprayed from the paint spraying port 3 as described above. And applied to the surface of the belt-like body 100. Thus, by providing the preliminary coating apparatus in the preceding stage of the roll coater in the continuous coating apparatus, the generation of a partial thin film thickness portion is prevented.

Next, examples will be described.
Table 1 below shows coating materials on the belt-shaped body at various slit widths (length in the sheet passing direction of the belt-shaped body of the coating spray port) and slit lengths (lengths in the width direction of the belt-shaped body of the coating spray port). The application state of is shown. In addition, as other conditions, the application flow rate is 20 to 50 liters / min, preferably 35 liters / min, and the strip width is 900 mm or less (however, greater than 850 mm) as a narrow band, As the wide band, a band having a plate width of 1200 mm or more is used. The configuration of the coating apparatus is the same as that shown in FIGS. Here, the slit length is 650 mm to 850 mm, which is shorter than the plate width of the strip.

As shown in Table 1, when the slit is too small, the coating liquid is insufficient in the wide band, and when the slit is too large, the coating liquid is excessive in the narrow band. Then, a slit having an optimum diameter, which is 750 mm × 8 mm in this embodiment, provides a good application state.
Table 2 below shows the state of application of the paint to the band when the band-shaped body having various plate widths is used and the line speed (plate passing speed) of the band-shaped body is changed. The paint is sprayed from a slit having a slit length of 750 mm and a slit width of 8 mm. This slit dimension is a dimension which has obtained the favorable application state in Table 1.

As shown in Table 2, when the strip widths are 850 mm and 1280 mm and the line speeds are 76 m / min and 150 m / min, a good coating state can be obtained.
The embodiment of the present invention has been described above. However, the present invention is not limited to being realized as the above-described embodiment.
That is, in the above-described embodiment, the slit dimension, that is, the dimension of the paint injection port has been specifically described. However, it is not limited to this. That is, when strips having various widths are passed, the slit lengths may have other dimensions as long as the slit length is shorter than the minimum width among the various widths. .

It is sectional drawing which looked at the structure of the coating device of embodiment of this invention from the front. It is sectional drawing which looked at the structure of the said coating apparatus from the side surface. It is a top view which shows the relationship between the width | variety of a strip | belt-shaped body, and the shape of a coating material injection nozzle. It is the figure used for description of the effect of this invention. It is a figure which shows the structure of the continuous coating apparatus provided with the said coating apparatus as a preliminary coating apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure equalizing chamber 2 Introducing pipe 3 Paint injection port 4a, 4b Lip 11 Preliminary coating device (painting device)
100 Band

Claims (4)

A pre- painting method for a strip that is continuously applied to a traveling strip,
A lip composed of a pair of brushes extending in the width direction of the belt-like body and having a rectangular slit shape shorter than the width of the belt-like body and extending in parallel across the slit is provided at a position facing the belt-like body. A method for pre- coating a belt-shaped body, wherein a paint is sprayed from a paint spraying port provided, and the lip is brought into contact with the belt-shaped body to apply the paint onto the belt-shaped body. The belt-shaped body having various widths is the object to be coated, and the length of the coating material spray port in the width direction of the belt-shaped body is shorter than the minimum width among the various widths. The method for pre- coating the strip according to claim 1. A pre- painting device for a belt-like body that continuously paints a traveling belt-like body,
A pressure equalization chamber for introducing paint,
A paint slit that extends in the pressure equalizing chamber in the width direction of the belt and has a rectangular slit shape shorter than the width of the belt, and sprays the paint in the pressure equalizing chamber;
A lip comprising a pair of brushes sandwiched between the paint spray ports and disposed along the paint spray ports and extending in parallel with the opening direction of the paint spray ports and contacting the strip-shaped body;
An apparatus for pre- coating a belt-like body. The belt-shaped body having various widths is the object to be coated, and the length of the coating material spray port in the width direction of the belt-shaped body is shorter than the minimum width among the various widths. The strip | belt-shaped body preliminary coating apparatus of Claim 3.

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