JPH04111903A - Method for controlling surface property in sheet rolling - Google Patents

Abstract

PURPOSE:To make the unevenness of gloss smaller, to prevent the generation of heat scratch and to obtain a rolled sheet excellent in surface property by controlling gloss based on the temp. and gloss of the rolled sheet that are continuously detected on the outlet side of the rolling mill. CONSTITUTION:The surface gloss of the rolled sheet S is continuously detected at adequate intervals for sampling with a temp. detecting device 51 and gloss detecting device 71. The detected value T of temp. and detected value (g) of glass are outputted to an arithmetic device 71 for control. Required rolling speed (v), temp. (t), flow rate (q) and concentration (c) of rolling oil are calculated with the arithmetic device 71 for control. Calculated results are respectively inputted to controllers 14, 27, 32, 42 and rolling speed, temp., flow rate and concentration of rolling oil are controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a method for controlling the surface properties of a rolled plate during plate rolling.

This invention is used for cold rolling rolled plates (including foils) made of common steel, stainless steel, titanium, titanium alloys, and other metal materials that require excellent gloss.

``Prior Art'' One of the qualities of metal plates used for electronic parts, decorations, home appliances, and other products is their luster. Generally, in order to obtain a rolled plate with excellent gloss, rolling is performed using work rolls with small surface roughness in the final bath.

Requirements regarding the gloss of rolled sheets have become increasingly diverse in recent years.

For example, a wide range of quality is required, from mirror bright to mirror flight, with a fairly constant surface roughness. Also,
As the amount of rolling increases, the surface of the work roll becomes rougher, and the gloss of the rolled plate gradually deteriorates, but it is necessary to maintain the required gloss over the entire length of the plate. Therefore, in the past, when the surface of a work roll became rough and the gloss level deteriorated to some extent, the work roll was replaced with a new one. On the other hand, in order to ensure productivity, it is required to create different gloss levels and guarantee gloss over the entire length of the L plate without changing the rolling oil.

[Problems to be Solved by the Invention] Conventionally, the glossiness of a rolled sheet has been observed by sampling at appropriate intervals during rolling, or by visually observing the rolling of one coil. Visual observation is not quantitative;
The observation error is also large. In addition, with sampling observations, it is not possible to continuously control the glossiness by changing the rolling conditions from time to time according to changes in glossiness over time, and observation results cannot be immediately reflected in the glossiness of the product. . For this,
There were many variations in gloss, and many products were scrapped because they could not achieve the required gloss. Therefore, there is an urgent need to develop continuous measurement of glossiness or continuous control of glossiness during rolling. Note that there is JIS Z 8741 (Glossiness Measuring Method) as a method for measuring the glossiness of industrial products.

Furthermore, if the rolling oil concentration is lowered, the rolling oil flow rate is reduced, or the rolling oil temperature is increased in order to increase the gloss of the sheet surface, beat scratches occur on the sheet surface.

Note that when the rolling speed is lowered, beat scratches do not occur and gloss increases, but productivity decreases.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a surface texture control method that can produce rolled plates with excellent surface properties at a high yield during plate rolling.

[Means for Solving the Problems] The surface texture control method of the present invention continuously detects the temperature and glossiness of a rolled plate on the exit side of a rolling mill. Then, at least one of the rolling oil concentration, rolling oil flow rate, rolling oil temperature, and rolling speed is controlled based on the detected values of the temperature and glossiness so that the rolled plate has a required glossiness. Here, rolling oil means only rolling oil or an emulsion of rolling oil and water.

A thermocouple thermometer, resistance thermometer, thermal radiation thermometer, or the like is used to detect the temperature of the rolled plate.

Moreover, the glossiness is detected with a normal glossmeter equipped with a light source and a light receiver.

In controlling the rolling oil concentration, rolling oil flow rate, rolling oil temperature, and rolling speed, one or more of these manipulated variables are controlled. Further, the relationship between these manipulated variables and the temperature and gloss of the rolled plate is determined in advance through experiments. Figure 1 shows
The effect of rolling speed and rolling oil concentration on the glossiness of the plate surface is shown.

As is clear from this graph, the rolling speed is lower,
Alternatively, as the rolling oil concentration decreases, the gloss level increases.

FIG. 2 is a graph showing the influence of rolling speed and amount of rolling oil on the glossiness of the plate surface.

FIG. 2 shows that the gloss level increases as the rolling speed decreases or the rolling oil flow rate decreases. FIG. 3 shows the effect of rolling oil temperature on the glossiness of the plate surface. FIG. 3 shows that as the rolling oil temperature increases, the gloss level also increases. FIG. 4 is a graph showing the influence of rolling speed and rolling oil concentration on plate temperature. According to FIG. 4, the lower the rolling oil concentration, the higher the plate temperature. Further, FIG. 5 is a graph showing the influence of rolling speed and amount of rolling oil on plate temperature. FIG. 5 shows that the smaller the rolling oil flow rate, the higher the plate temperature. moreover,
FIG. 6 is a graph showing the influence of rolling speed and rolling oil temperature on plate temperature. According to FIG. 6, the lower the rolling oil temperature, the lower the plate temperature. These data are stored in the control arithmetic unit and are used to determine the required operation amount based on the detected temperature and glossiness of the rolled plate.

The rolling oil concentration is controlled by using a rolling oil mixer such as a static mixer. When rolling oil No. 100 is used, rolling oil concentration control is not performed. The rolling oil flow rate is controlled by controlling the pump flow rate of the rolling lubrication system. Further, the rolling oil temperature is controlled by controlling bitters in the rolling oil tank and the like. Further, the rolling speed is controlled by controlling the circumferential speed of the work roll drive motor.

In gloss control, the use of manipulated variables such as rolling oil concentration, rolling oil flow rate, rolling oil temperature, and rolling speed will be explained by way of example. Since rolling oil temperature has a slow response, it is controlled on a coil-by-coil basis. The control within the coil is based on the rolling oil concentration or the rolling oil flow rate, and if the rolling oil concentration or the rolling oil flow rate is outside the upper or lower limit values, the rolling speed is controlled.

Beat scratches occur when the sheet temperature immediately after rolling exceeds a certain limit value. Therefore, the concentration, flow rate, or temperature of the rolling oil is controlled within the limit temperature range for generating beat scratches shown in FIGS. 4 to 6.

"Operation" The temperature and gloss of the rolled plate are continuously detected at the exit side of the rolling mill, and based on the detected values, the rolling oil concentration, rolling oil flow rate,
The rolling oil temperature or rolling speed is controlled within the limit temperature range for generating beat scratches. Therefore, the glossiness is controlled with high accuracy and quick response, and the temperature of the rolled plate is kept within the limit temperature range for generating beat scratches.

[Example] FIG. 7 shows an example of rolling equipment that implements the surface texture control method of the present invention.

The work rolls 12 of the final stand 11 of the cold rolling mill row are driven by a motor 3, and the motor 13 is controlled by a controller 14.

A spray nozzle 21 for supplying an emulsion of rolling oil and water to the roll bite is arranged on the entry side of the rolling stand 11. The used emulsion is collected in the tank 23. The tank 23 is replenished with water or rolling oil as much as it has been consumed by the pump 14. The temperature of the emulsion in the tank 23 is maintained at a required temperature by a heater 26 controlled by a controller 27. The emulsion flows from the tank 23 to the piping 29, the variable displacement pump 31,
The spray nozzle 2 is returned to the spray nozzle 2 via the electromagnetic switching valve 34 and the piping 36.
1.

The controller 32 controls the variable displacement pump 31 to adjust the amount of emulsion supplied. In addition, a static mixer 39 is provided in the piping 37 on the outlet side of the electromagnetic switching valve 34.
is connected. The static mixer 39 is supplied with rolling oil or water from a variable displacement pump 41. In the static mixer 39, the emulsion from the tank 23 and the rolling oil or water from the variable displacement pump 41 are mixed, the concentration is adjusted, and the emulsion is sent to the spray nozzle 21 via piping 44.
supplied to The concentration is adjusted by controlling the variable displacement pump 41 using the controller 42. When controlling the temperature and flow rate as well as the concentration of rolling oil, use the electromagnetic switching valve 3.
4 is switched to position A, and switched to position B when controlling the temperature and flow rate of rolling oil.

Adjacent to the exit side of the rolling stand 11, a temperature detection device 51 is installed.
is located. As shown in FIG. 8, the temperature detection device 51 includes a plurality of chromel/alumel thermocouples 54 attached to the outer peripheral surface of a hollow roll 52. Hollow roll 52
The surface of is coated with alumina so that the thermocouple 54 is exposed. Therefore, the thermocouple 54 is in contact with the rolled plate S, and the hollow roll 52 and the thermocouple 54 and the thermocouples 54 are insulated from each other. A guide hole (not shown) communicating with the inside of the roll is provided on the surface of the hollow roll 52, and the thermocouple 54 is drawn into the inside of the roll through this guide hole. Further, the thermocouple 54 is connected to the hollow roll 52
It is connected through a slip ring 56 to a signal processing circuit 58 equipped with a standard (not shown).

A glossiness detection device 61 is installed adjacent to the output side of the temperature detection device 51.
is located. The glossiness detection device 61 includes a wiper roll 62, presser rolls 64, 65, 66, and a glossmeter 68. The wiper roll 62 is in contact with the upper surface of the rolled plate S, the presser roll 65 is in contact with the lower surface of the rolled plate S, and the presser rolls 64 and 66 are in contact with the upper surface of the rolled plate S, respectively. The gloss meter 68 is placed directly above the presser roll 65. The gloss meter 68 includes a light source that illuminates the upper surface of the rolled plate S and a phototube (both not shown) that detects reflected light from the upper surface of the rolled plate S.

Such gloss meters 68 are arranged at one location at the center of the board width, or in a plurality of sets (for example, three sets arranged near the center and both ends) along the board width direction. The wiper roll 62 wipes away scale, rolling oil, etc. attached to the rolled plate S, thereby cleaning the plate surface.

Furthermore, the presser rolls 84, 65, and 66 suppress the vertical vibration of the rolled plate S and prevent the plate from waving, so that the light from the light source of the gloss meter 68 is not scattered on the plate surface. As a result, the glossiness of the rolled plate S can be detected accurately.

In the rolling equipment configured as described above, the temperature detection device 51 and the glossiness detection device 71 continuously detect the surface glossiness of the rolled sheet S at appropriate sampling intervals (for example, 0.55 ec). The temperature detection value T and the glossiness detection value g are output to the control arithmetic device 71. The control arithmetic unit 71 determines the required rolling speed V, rolling oil temperature t, rolling oil flow rate q, and rolling oil concentration C based on the detected values of temperature and glossiness and the data shown in FIGS. 1 to 6. Calculate. The calculation results are input to controllers +4.27 and 32.42, respectively, and the rolling speed, rolling oil temperature, rolling oil flow rate, and rolling oil concentration are controlled.

In this embodiment, all of the rolling speed, rolling oil temperature, rolling oil flow rate, and rolling oil concentration are controlled, but one to three of these manipulated variables may be controlled. Further, in order to independently control the glossiness of the upper and lower surfaces of the plate, gloss meters may be arranged above and below to control the rolling oil flow rate and/or the rolling oil concentration of the upper and lower surfaces of the plate.

Here, a specific example of gloss control in the above-mentioned rolling equipment will be explained.

A 5IJS430 flight material was rolled under the following rolling conditions.

Work roll diameter: 80mm Plate thickness: 0.78mm Reduction ratio: 14* Work roll surface roughness: Approximately 005μm Ra Inlet tension 2
2kgf/mm2 Output tension + 31kgf/nu++2 Rolling speed: 400m/min.

During rolling under the above conditions, the glossiness of the rolled plate was continuously detected, the required rolling oil temperature was determined based on the detected value, and the heater 26 was controlled by the controller 27. As a result, by changing the rolling oil temperature from 30°C to 60°C, the glossiness of the plate surface (average value in the longitudinal direction and width direction of the plate) was reduced to G.

(45").However, when the rolling oil temperature is 60℃, the plate temperature becomes 160℃, which is the limit temperature for beat scratch generation (15").
3°C), and slight beat scratches occurred. Therefore, the temperature of the rolled plate was further detected, and the temperature of the rolling oil was controlled with reference to the detected temperature. As a result, the plate temperature was maintained at 153° C. or lower, and no beat scratches occurred.

In addition, the gloss level of the board surface is 80 to 120 at Gs (45°).
A stable plate surface quality was achieved.

In addition, the hollow roll of the temperature detection device has a diameter of 100 mm
It is 1200mm and made with a 5US304 vibe. Also, the size of the wiper roll is 100 mm in diameter.
mm x 120 Onon, the roll body is made of cast iron, and the surface is covered with cloth about 5 mm thick. The size of the presser roll is 100 mm in diameter x 1200 mm.

[Effects of the Invention] According to the present invention, the glossiness is controlled based on the temperature and glossiness of the rolled plate that are continuously detected on the exit side of the rolling mill.

Therefore, since the glossiness is controlled by high particle size and fast response, variations in glossiness are reduced and beat scratches do not occur. As a result, a rolled plate with excellent surface properties can be obtained, and the yield can be improved.

[Brief explanation of the drawing]

Figure 1 is a graph showing the influence of rolling speed and rolling oil concentration on the glossiness of the plate surface. Figure 2 is a graph showing the influence of rolling speed and rolling oil amount on the glossiness of the plate surface. Figure 3. is a graph showing the influence of rolling oil temperature on the glossiness of the plate surface, Figure 4 is a graph showing the influence of rolling speed and rolling oil concentration on plate temperature, and Figure 5 is a graph showing the effect of rolling speed and rolling oil concentration on plate temperature. A graph showing the influence of rolling oil flow rate, FIG. 6 is a graph showing the influence of rolling speed and rolling oil temperature without affecting plate temperature, and FIG. 7 shows an example of rolling equipment implementing the surface texture control method of the present invention. The equipment configuration diagram and FIG. 8 are perspective views of a temperature detection device provided in the rolling equipment of FIG. 7. 11... Plate rolling stand, 12... Work roll,
13...Motor, 14...Controller, 21
... Spray nozzle, 24... Pump, 23... Tank, 26... Heater, 27... Controller,
31... Variable capacity pump, 32... Controller, 34... Solenoid switching valve, 39... Static mixer, 41... Variable capacity pump, 42... Controller, 51... Temperature detection device , 52...Hollow roll, 54...Thermocouple, 56...Slip link, 5
8... Signal processing circuit, 61... Glossiness detection device, 6
2... Wiper roll, 64, 55. 66... Presser roll, 68... Gloss meter, 71... Control calculation device.

Claims (1)

[Claims] 1. Continuously detect the temperature and glossiness of the rolled plate on the exit side of the rolling mill, and adjust the rolling oil concentration based on the detected values of the temperature and glossiness of the rolled plate so that the rolled plate has the required glossiness. (
A method for controlling surface texture in plate rolling, characterized by controlling at least one of the following: (rolling oil includes an emulsion of rolling oil and water), rolling oil flow rate, rolling oil temperature, and rolling speed.