JP3199988B2 - Steel sheet marking method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for manufacturing a semiconductor device which has a temperature of 300.degree.
The present invention relates to a method of performing marking on a steel plate or the like having a temperature in the range described above by an air atomizing method.

[0002]

2. Description of the Related Art In general, marking on a steel plate or the like is a display of a required specification of a customer, and is used as a key for identifying an actual product in a refinement processing line after a shearing line in a factory. It is required to display clear and precise characters. Further, processing from placing the shearing main line is directly connected to the rolling line, as a highly device equipment reliable to ensure the production process, the passing plate material all with high efficiency
Must be reasonable .

FIG. 3 is a schematic configuration diagram of a conventional steel sheet marking apparatus. At the time of marking, the needle valve 40 is opened and the pressurized paint is discharged from the paint nozzle 41, and at the same time, the pressurized air is discharged from the air nozzle 42 to mix the paint with the air to form a fine particle mist. In this way, a so-called air atomizing type marking is performed in which a marking dot coating 44 having a specified dot diameter is formed by spraying the surface 43 to be marked on the steel plate.

FIG. 4 is a view showing a conventional two-fluid spray nozzle, and FIG. 4A is an enlarged view of a nozzle tip portion.
(B) is a sectional view of the tip of the nosol. In this case, for example, as shown in FIG. 4 (b), after the paint is discharged from the paint nosol 50 and marked on the steel plate, the cleaning liquid is discharged from the cleaning liquid nozzle 51 concentrically arranged on the outer periphery thereof. Wash the paint.

[0005] In the case of the example shown in FIG.
Uses a water-soluble paint as high as 00 ° C and uses an air atomizing method in all temperature ranges from room temperature to high temperature.However, nozzle clogging is more likely to occur than organic paints. Must be bigger.

On the other hand, in the case of the example shown in FIG. 4, marking is performed by an airless method, and the coating material is an organic type having a boiling point of 60 ° C., so that the coating can be performed from room temperature to 100 ° C. In the case of the high-temperature steel sheet described above, the coating material evaporates and is not put on the steel sheet, but is rejected in a powdery state, making marking impossible.

[0007]

However, in the conventional example described above, for example, in the case of FIG. 3, since the marking of the air atomizing method is performed, high-temperature material marking from normal temperature to 300 ° C. is possible, but nozzle clogging is not possible. Since the diameter of the nozzle must be increased for prevention, the dot diameter of the marking is inevitably increased, so that there is a problem that clear marking cannot be performed when printing a thick plate.

In the case of FIG. 4, although the water-soluble paint which is slow in drying at room temperature and the nozzle is liable to be clogged is replaced with an organic paint, the nozzle diameter can be reduced. There is a problem that high-temperature materials of 100 ° C. or more cannot be used for printing.

Accordingly, an object of the present invention is to provide a steel sheet marking method capable of preventing a nozzle clogging and always maintaining a dot diameter of φ4 mm over the entire temperature range from room temperature to 300 ° C. to enable clear marking. To provide.

[0010]

SUMMARY OF THE INVENTION The steel sheet marking method of the present invention prevents a nozzle from clogging when performing marking on a steel sheet or the like having a temperature range of 300.degree. This is a steel sheet marking method that enables clear marking while always maintaining the dot diameter φ4 mm over the entire temperature range.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to achieve the above object, the invention according to the first aspect of the present invention is to hold a dot of φ4 mm by an air atomizing method using a double tube nozzle and to reduce the temperature from normal temperature to 30%.
In the marking method for steel sheets up to 0 ° C,
Spray from the nozzle tip depending on the temperature of the material to be marked
Characterized by marking by controlling the particle size of paint
I have.

[0012]

[0013]

According to the first aspect of the present invention, the particle diameter of the paint sprayed from the nozzle tip is controlled so as to be changed according to the temperature of the material to be marked. Clear marking can be performed while maintaining the diameter at 4 mm.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a process chart showing a method for controlling steel plate marking according to the present invention .

In FIG. 1, 1 is an air compressor for compressing air, 2 is a pressure regulating valve for air, 3 is a solenoid valve for ON / OFF of air, 4 is a compressor for paint,
5 is a paint pressure control valve, 6 is a paint ON / OFF solenoid valve, 7 is a cleaning fluid compressor, 8 is a cleaning fluid pressure control valve, 9 is a cleaning fluid ON / OFF solenoid valve, and 10 is the temperature of the running steel plate. Numeral 11 is a double tube nozzle having a paint discharge nozzle at the center and an air / washing liquid discharge nozzle at the outer periphery thereof for performing marking by the air atomizing method.

Next, the operation will be described.

When marking a running steel sheet or the like by the air atomizing method, the air (air) system compresses air with an air compressor 1 and adjusts and sets the pressure with a pressure adjusting valve 2 to set a double pipe nozzle 11. To the air / washing liquid discharge nozzle.

On the other hand, in the paint system, the paint compressed by the paint compressor 4 is supplied to the paint discharge nozzle of the double pipe nozzle 11 after adjusting and setting the pressure by the pressure regulating valve 5.

The paint pressure and the air pressure set in this case are controlled by the temperature of the steel sheet measured by the radiation thermometer 10. For example, when the temperature of the steel sheet is high, the paint discharge pressure is decreased and the air discharge pressure is increased. And so on. The distance between the nozzle tip and the steel plate is also adjusted according to the temperature of the steel plate, and the distance between the steel plates is controlled to be shorter as the temperature becomes higher.

These compressed paint and compressed air are discharged and mixed from the double tube nozzle 11 respectively, and dot spraying marking is performed on the steel plate as specified φ4 mm dots.

When the first marking is completed, the solenoid valve 3
And 6 are turned off to stop the supply of paint and air, the electromagnetic valve 9 is turned on to supply the cleaning liquid to the air / cleaning liquid discharge nozzle, and the double pipe nozzle 11 is cleaned to prevent nozzle clogging. Prepare for marking.

After the elapse of the cleaning time, the electromagnetic valve 9 is turned OFF to stop the supply of the cleaning liquid. Immediately before the next steel plate marking in the running marking, the electromagnetic valve 3 is turned on for a predetermined time to supply air to the double pipe nozzle 11. And blow off the remaining washing liquid and residual paint to clean.

After the nozzle 11 has been cleaned, the electromagnetic valve 6 is also turned on and compressed paint and compressed air are supplied to the double pipe nozzle 11 to mark the next steel sheet as in the first case.

The processing procedure of the above-described discharge switching control can be simply arranged as follows.

Process 1, air / paint discharge mixing and spraying, Process 2, cleaning liquid discharge, process 3, air discharge immediately before next marking, process 4, air / paint discharge mixing spraying at the time of next marking. Becomes In this example , since an organic coating material having a boiling point of 60 ° C. is used, it is more efficient to use airless printing in a normal temperature (〜90 ° C.) region and air atomizing printing in a high temperature (90 to 300 ° C.) region. And clear marking becomes possible.
In addition, since only the cleaning liquid is discharged and cleaned after marking, the cleaning liquid stays in the nozzle tip due to surface tension, preventing paint from drying and adhering to the nozzle due to the high temperature on the steel plate side and causing nozzle clogging. Immediately before the marking, the residual liquid is completely cleaned to remove the adverse effect on the marking, so that clear marking can be performed.

Next , the relationship between the steel sheet temperature and the paint particle size will be described.

FIG. 2 is a diagram showing the relationship between the steel sheet temperature and the paint particle size according to the present invention .

According to the present invention , the size of the particle diameter of the mist sprayed from the nozzle 11 is controlled by the temperature of the steel sheet of the material to be marked. In order to reliably maintain the dot diameter φ4mm, which is the marking unit, paint and air are discharged from the double pipe nozzle 11 and mixed, and marking is performed on a high-temperature steel sheet by air atomizing printing, but the temperature of the steel sheet increases. As the particle size of the paint sprayed increases, the degree of evaporation increases and the degree to which the paint does not fall on the steel plate increases, resulting in a dot diameter of φ4 m.
Therefore, it is necessary to reduce the particle diameter of the paint as the indication of the radiation thermometer 10 increases, so as to maintain the dot diameter φ4 mm of the marking unit.

To reduce the particle size of the paint, a method such as increasing the air pressure is used.
The optimum paint particle size is determined empirically by actual measurement by taking the particle size and the steel sheet temperature on the horizontal axis. As a result, the optimum paint particle size is determined when the plate temperature is between room temperature and 90 ° C. Particle size is φ4mm When plate temperature is 90 ~ 130 ℃, paint particle size is φ2.0 ~
2.5mm When the plate temperature is 130 ~ 170 ℃, the particle size of paint is φ1.5 ~
2.0mm When the board temperature is 170-200 ° C, the paint particle size is φ1.0 ~
1.5mm When the plate temperature is 200 ~ 300 ℃, the paint particle size is φ0.5 ~
1.0 mm. The paint particle size is obtained by measuring the paint particle size when the steel plate is in contact with the steel plate. Finally, as a total, the dot diameter φ4mm, dot interval 5mm, steel sheet speed up to 60m by the air atomizing printing method using the double tube nozzle 11.
Table 1 shows the actual measured values of the paint discharge pressure, the air discharge pressure, and the paint particle size that enable clear marking under the conditions of pm and steel sheet temperature in the range of room temperature to 300 ° C.

As described above, in the present invention, the dot diameter φ4 mm can be maintained by controlling the paint particle size to the optimum value, airless printing is performed in a normal temperature (up to 90 ° C.) region, and air atomization is performed in a high sound range of 90 to 300 ° C. As a printing method, clear marking is possible in all temperature ranges, and it is also suitable for printing thick plate products.

[0033]

[Table 1]

[0034]

As described above, according to the first aspect of the present invention, the particle size of the paint sprayed from the nozzle tip is reduced.
Control to change according to the temperature of the steel sheet to be marked
Marking, even when the steel plate temperature is in the high temperature range
The dot diameter of φ4mm is kept from normal temperature to 300 ° C.
Clear marking is possible over the entire temperature range.

[0035]

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for controlling steel sheet marking according to the present invention .

FIG. 2 is a diagram showing the relationship between the particle size of a paint and the temperature of a steel sheet according to an example of the present invention.

FIG. 3 is a schematic configuration diagram of a conventional steel sheet marking device.

FIG. 4 is a view showing a conventional two-fluid spray nozzle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air compressor 2 Air pressure control valve 3, 6, 9 Solenoid valve 4 Paint compressor 5 Paint pressure control valve 7 Cleaning liquid compressor 8 Cleaning liquid pressure control valve 10 Radiation thermometer 11 Double pipe nozzle

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-50-122540 (JP, A) JP-A-6-7717 (JP, A) Fully open 1986-19457 (JP, U) Really open 149012 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B05D 5/06 B05D 1/02 B05D 7/14 B05B 5/025

Claims (1)

(57) [Claims] 1. Using a double tube nozzle, hold a dot of φ4 mm by an air atomizing method, and maintain the dot from normal temperature to 300 ° C.
A method for marking steel plates, wherein the marking is performed by controlling the particle size of the paint sprayed from the nozzle tip according to the temperature of the material to be marked.