JPS62148015A - Grinding method and device for hot rolled hoop - Google Patents

Abstract

PURPOSE:To uniformly and positively remove scales having unevenly distributed pickling property on a hot rolled hoop by combining and using the respective proper number of center grinding rolls and edge grinding rolls. CONSTITUTION:A hot rolled hoop 1 is stably set, center grinding rolls 4a and 4b are aligned with the line center X by using driving devices 14a, 14b, 15a-15d, and the outside edge of edge grinding rolls 5a-5d is aligned with the outside edge of the hoop 1. The number of grinding passes of the center grinding rolls 4a, 4b, and of the edge grinding rolls 5a-5d are varied and a screwdown amount of every rolls is changed in accordance with relative pickling difficulty in the lateral direction of the hoop 1. In this method, stepped wear caused by various plate widths is eliminated, so that surfaces having nearly uniform pickling property are obtained by that grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application> The present invention relates to a hot-rolled steel strip grinding method and apparatus for mechanically removing oxidized scale generated on the surface of the hot-rolled steel strip.

<Prior art> Normally, scales are continuously removed from hot-rolled steel strips in a pickling line, but in order to facilitate and ensure scale removal in this pickling line, prior to this, Various methods have been proposed for mechanically removing scale from the surface of the steel strip.

Among them, Japanese Patent Publication No. 56-16389 proposes a pickling method for hot-rolled steel brooms.

This method involves grinding both ends of the steel strip over a width of 50 to 200 mm on each side with a brush roll or the like to remove scale before introducing it into the pickling line. The aim is to improve the pickling performance of the edge parts, which have poor pickling properties compared to the width center part, and to make the pickling properties uniform across the board width. The pickling speed (e.g., 100 m/min or less) was changed to the speed corresponding to the pickling performance at the center of the board width (e.g., 300 m/min or less).
The aim is to improve the pickling efficiency by increasing the pickling efficiency to about 500 m/min.

However, "Tetsu to Hagane" No. 12 (published in 1975) 16
As shown in the research paper ``About the pickling properties of hot-rolled steel scales'' on page 8, the pickling properties of the scales on the surface of normal hot-rolled steel strips vary in an almost W-shape across the width of the strip. ing.

In other words, in addition to both edge portions of the steel strip, the central portion also has low pickling properties. FIG. 5 shows the distribution of pickling properties in the width direction of the strip steel. Material A1 in the figure. i'Water cooling after winding at a winding temperature of 600"C; Material B shows the case of winding at a winding temperature of 600"C and air cooling after winding.

Therefore, if the above-mentioned descaling pretreatment method by grinding only the plate edges is applied to a steel strip having pickling properties with a W-shaped distribution, the scale in the central part in the width direction of the plate will remain and the pickling process will be difficult. There was a problem in that the pickling performance in the board width direction within the line became non-uniform, resulting in a decrease in the efficiency of the pickling line. Therefore, at present, a wide integral roll is used in which the body length of the grinding brush roll is matched to the maximum processing plate width.

<Problems to be Solved by the Invention> However, when a wide integral roll as described above is used, when grinding a narrow steel strip, the brush roll has a part that contacts the steel strip and a non-contact part. As a result, the grinding roll has to be replaced with a new one the next time a wide steel strip is to be ground, resulting in an increase in maintenance costs.

In addition, since the steel strip is ground uniformly across the width of the strip,
When grinding a steel strip that has non-uniform pickling properties across the width of the strip, the pickling properties remain non-uniform, resulting in the problem that the efficiency of the next pickling process is not improved. .

In view of these circumstances, the present invention provides a rational scale grinding method that can be applied to hot rolled steel strips of various strip widths that have a non-uniform pickling property distribution across the strip width, and an apparatus used in the method. The purpose is to

Means for Solving the Problems> The configuration of the hot-rolled steel strip grinding method according to the present invention that achieves the above-mentioned object is to grind the surface of the hot-rolled steel strip conveyed from the scale breaker to the steel strip. fft
A pair of end grinding rolls that are capable of grinding only the center portion of the upper and lower surfaces of the strip plate using a central grinding roll that is capable of grinding only the center portion in the width direction of the strip steel described in I, and that are capable of grinding only both ends of the strip plate. The upper and lower ends of the steel strip are ground by the end grinding rolls so that the outer edge of the steel strip in the width direction of the strip substantially coincides with both edges of the strip in the width direction of the strip, and the hot-rolled steel strip is The configuration of the grinding device for hot-rolled steel strip is such that the surface of the hot-rolled steel strip conveyed from the scale breaker is ground by a grinding roll that is rolled down on the steel strip and is driven to rotate. At least one central grinding roll capable of grinding only the center portion of the steel strip in the plate width direction is disposed on each of the upper and lower surfaces of the steel strip, and a pair of end grinding rolls capable of grinding only both ends of the steel strip. A special feature characterized in that at least one pair or more of rolls are arranged on the upper and lower surfaces of the steel strip, and each of the end grinding rolls is provided with a drive mechanism capable of moving each of the end grinding rolls in the width direction of the steel strip. Embodiment> Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of the grinding apparatus according to the present embodiment, FIG. 2 is a longitudinal cross-sectional view showing the roll arrangement, and FIGS. 3 and 4 are arrows taken along lines AA and B-B in FIG. 1, respectively. This is a perspective view. As shown in these drawings, a scale breaker (not shown) is attached to the hot-rolled steel strip 1, and the exit side ringer roll 2a.

2b and the hot rolled steel strip 1 are sent in the direction of arrow Z while being supported by six support rolls 3a to 3f arranged in a staggered manner on the upper and lower sides. In addition, there are central grinding rolls 4a and 4b, one each on the upper and lower sides, at positions facing the support rolls 3a and 3b, and two upper and lower central grinding rolls at positions facing the support rolls 3a to 3f.
Each set of end grinding rolls 5a to 5d is provided.

Here, the end grinding rolls 5a to 5d each consist of a pair of independent rolls on both sides in the sheet width direction. central grinding roll 3a,
3b and end grinding rolls 5a to 5d are commonly known ones, such as nylon brushes containing abrasive grains or metal wire brushes, and motors 6a, 6b and motor 7, respectively.
The frames lOa, 10b, lla to 7d are driven to rotate in the opposite direction to the traveling direction of the band W41 as shown by the arrows in FIG. It can be moved up and down within the lid. Moreover, each frame 10a.

10b, 11a to 11d are mobile carts 12a, respectively.
, 12b, 13a to 13d, and the drive devices 14a, 14b, 15a to 15d
Therefore, it is configured to be able to freely reciprocate on the rails 16a, 16b, 17a to 17d in the roll axis direction (width direction of the steel strip 1).

Here, the body length (l, ) of the central grinding rolls 4a, 4b is set to be approximately equal to the minimum width (B1) of the steel strip 1 to be processed, and the body length (12) of the end grinding rolls 5a to 5d is may be determined so that the value of I +2j is slightly larger than B with respect to the maximum board width (B2). In other words, when the outer edges of the edge grinding rolls k 5 a to 5 d match the edge of the plate width of the steel strip 1, the inner sides of the edge grinding rolls 5 a to 5 d and both ends of the central grinding rolls 4 a and 4 b What is necessary is to overlap each other in the board width direction. In addition, X in the diagram
18 indicates the line center line, and 18 indicates the dust cover.

In the device of this embodiment, the central grinding roll 4a.

4b on the upstream side in the traveling direction of the steel strip 1, the end grinding roll 5
Although the rollers a to 5d are arranged on the downstream side, they may be arranged in the opposite direction.
There is no problem even if a to 5d are arranged alternately.

Next, a grinding method using the above-mentioned apparatus will be explained. When the belt ff4i to be ground is stabilized, first, the drive devices 14a, 1
Central grinding roll 4a using '4b, 15a-15d
, 4b are aligned with the line center X, and the outer edges of the end grinding rolls 5a to 5d are aligned with the outer edge of the band w41.

Hereinafter, the grinding may be carried out according to conventionally known directions, but the steel strip 1
For example, the center part of the board with good pickling property is ground by center grinding 4a, 4b in accordance with m5 degree of pickling property in the width direction of the board.
Both ends of the plate with poor pass grinding and pickling properties are edge grinding rolls 5a.
By arbitrarily changing the number of grinding passes in the width direction of the strip, such as 2-3 passes of grinding with ~5d, and selecting the rolling profile of each roll appropriately, the steel strip 1 can be ground almost uniformly across the width of the strip. It is possible to grind to a surface that has pickling properties. This greatly improves the efficiency of the pickling line in the next process.

As explained above, if grinding is performed as described above with the apparatus of this embodiment, all rolls 4a, 4b will be removed regardless of the width of the steel strip 1.
, 5a to 5d will always be in contact with the surface of the band W41, so there will be no step wear due to changes in the sheet width, unlike in conventional wide single rolls. This can contribute to reducing maintenance costs.

<Effects of the Invention> As specifically explained above in conjunction with the examples, according to the present invention, the number of grinding passes and the amount of reduction can be adjusted to prevent uneven pickling properties over the width direction of hot rolled steel strips. This can be achieved by freely changing the width of the plate, making it possible to grind to a surface with a uniform pickling property, which can greatly improve the efficiency of the pickling line in the next process. . Further, according to the present invention, since there is no fear of stepped wear on the grinding roll, it is possible to contribute to reducing maintenance costs by extending the life of the grinding roll.

[Brief explanation of drawings]

FIG. 1 is a plan view of a hot-rolled steel strip grinding apparatus according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing the roll arrangement thereof, and FIG. 3 is a line taken along line A-A in FIG. 1. The arrow view, Figure 4 is B- in Figure 1.
FIG. 5, which is a view taken along the line B, is a graph showing the distribution of pickling properties in the width direction of the steel strip. In the drawing, 1 is a hot rolled steel strip, 2a and 2b are ringer rolls, 3a to 3f are support rolls, 4a and 4b are central grinding rolls, 5a to 5d are edge grinding rolls, 6a, 6b, ? a to 7 d are motors, 8 a
, 8b, 9a to 9d are rolling down devices.

Claims (1)

[Claims] 1) When grinding the surface of a hot-rolled steel strip conveyed from a scale breaker using a grinding roll that is rolled down and rotated against the steel strip, the plate width of the steel strip is A central grinding roll capable of grinding only the central part in the direction grinds the central part of the upper and lower surfaces of the strip, and a pair of end grinding rolls capable of grinding only both ends of the strip on the outside in the width direction of the strip. A method for grinding a hot rolled steel strip, comprising grinding both upper and lower ends of the steel strip using the end grinding rolls with the edges substantially matching both edges in the width direction of the strip. 2) In a hot-rolled steel strip grinding device that grinds the surface of a hot-rolled steel strip conveyed from a scale breaker using a grinding roll that is rolled down and rotated against the steel strip, the plate of the steel strip is At least one central grinding roll capable of grinding only the central portion in the width direction is provided on each of the upper and lower surfaces of the steel strip, and a pair of end grinding rolls capable of grinding only both ends of the steel strip are disposed on the steel strip. Grinding of hot rolled steel strip, characterized in that at least one or more rollers are disposed on the upper and lower surfaces of the roller, and each of the end grinding rolls is provided with a drive mechanism capable of moving each of the end grinding rolls in the width direction of the steel strip. Device.