JPS6234776A - Surface treatment of steel sheet - Google Patents

Abstract

PURPOSE:To improve substantially overall blow efficiency of abrasive material by blowing abrasive material against a moving steel sheet, with the blow slanted to form an acute angle against both the steel sheet movement direction and the steel sheet width direction, thereby reducing loss of energy due to collisions within the abrasive material. CONSTITUTION:From plural centrifugal blow devices 2 placed side by side under a steel sheet 1 moving in one direction, abrasive material 3 is blown against the steel sheet 1. In this case, the abrasive material 3 is blown with a slant to form an acute angle against both the direction of movement of the steel sheet 1 and the direction of the width of the steel sheet. Namely, the abrasive material 3 is blown in plural blow areas having small spread areas over the direction of sheet width (d) of the steel sheet 1 to combine plural blow areas in the sheet width direction to form a compound effective blow area. As a result, ineffective flow of the abrasive material 3 is lessened, loss of energy due to collision within the abrasive material is lessened, and blow efficiency of the abrasive material 3 is enhanced.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a method for surface treatment of a steel plate, in which the surface of the steel plate is efficiently treated by projecting an abrasive material such as shot or grid onto the steel plate using centrifugal force. It is about the method.

(Prior Art) In recent years, a mechanical method has been devised to replace the conventional pickling method as a method for removing scale generated on the surface of steel sheets produced by hot and cold rolling mills. As shown in FIG. 3, the principle is that a plurality of centrifugal projection devices (12) project the abrasive material (13) toward the steel plate (11). In this case, multiple centrifugal projection devices (12)
The abrasive material (13) projected from the steel plate (11) is projected so that its projection area spreads in the same direction as the plate width (d) direction of the steel plate (11).
) is used to peel off scale generated on the surface of the steel plate (11) due to the impact upon collision.

(Problems to be Solved by the Invention) However, when using such a mechanical method, pollution-free and highly efficient descaling is possible; ) is the projection area of the steel plate (
11) is wide and constant in the board width (d) direction, so even if you try to adjust the projection area width of the abrasive material (13) by controlling the number of operating centrifugal projection devices (12), There was a problem in that the adjustment width became too large to accommodate the wide plate width (d). by the way,
Centrifugal projection device! (12) is generally operated in all units regardless of the width (d) of the steel plate (11);
) When processing a steel plate (11) with a narrow width, the amount of wasted abrasive material (+3a) that is wasted becomes very large, and the projection efficiency decreases, and this wasted abrasive material (13a)
directly collides with the cabinet (not shown), causing premature wear of the cabinet.

(Means for Solving the Problems) The present invention has been completed with the aim of providing a surface treatment method for steel plates with high projection efficiency, which solves the above-mentioned problems. In a steel plate surface treatment method in which scale is removed from the surface of the steel plate by projecting an abrasive material toward the advancing steel plate, the abrasive material is projected from the projection port of each centrifugal projection device in both the advancing direction and the width direction of the steel plate. It is characterized by projecting the image at an acute angle.

That is, in the method for surface treatment of a steel plate according to the present invention, abrasive material is projected from a plurality of centrifugal projection devices in the same direction as the traveling direction of the steel plate, and thereby abrasive material is projected from each projection port in the width direction of the steel plate. An effective projection area is formed by combining a plurality of narrow projection areas, and the projection angle is set at an angle to the steel plate to reduce energy loss due to collisions between the abrasive materials.

(Example) Next, an example of the present invention will be described based on FIGS. 1 and 2. il+ is a steel plate that advances in one direction,
Multiple centrifugal projection devices (2) arranged below it (
The projection direction of the abrasive material (3) projected from 2) is inclined toward the advancing direction of the steel plate +11 shown by the arrow in FIG. The abrasive material (3) is projected at an acute angle to the steel plate (11) at an angle to both the traveling direction and the width direction of the steel plate (11).In other words, a plurality of centrifugal projection devices (2) The abrasive material (3) projected from the steel plate (11) is made into multiple narrow projection areas with little spread in the width direction (d) of the steel plate (11), and these multiple projected rain areas are combined in the width direction of the plate. The projected abrasive material (3) collides with the steel plate +11 and is reflected in the direction of the centrifugal projection device (2), so that an effective projection area covering the entire width of the plate is formed. The projection angle is also inclined in the width direction of the steel plate Tl) so that the projection angle β0 does not interfere with the scavenging material (3).

In this way, since the projection area of the abrasive material (3) from each projection port narrowed in the direction of the width (d) of the steel plate Tll is combined and projected in the direction of the width of the steel plate Tll, the centrifugal projection device (2 ) can be adjusted according to the sheet width (d) to reduce the amount of wasted abrasive material (3a) that is wasted, and the projection angle can also be set at an acute angle to the width direction of the steel sheet, i.e. Since the projection angle β0 is set to less than 90 degrees, energy loss due to collisions between the abrasive materials is reduced, and the overall efficiency of abrasive material projection is improved, greatly increasing productivity. can. Incidentally, a steel plate with a width of 600-1 mm was subjected to surface treatment using the conventional method shown in Figure 3 and the method of the present invention shown in Figures 1 and 2. According to the results of measuring the degree of scale reduction occurring on the surface of the steel plate by changing the moving speed of the steel plate during the treatment process, it was found that when using the method of the present invention, the moving speed of the steel plate was lower than that using the conventional method.
Even if it was doubled or more, the degree of scale reduction was comparable to that of the conventional one.

(Effects of the Invention) As is clear from the above description, the present invention includes a method in which the abrasive material projected from the projection ports of a plurality of centrifugal projection devices is inclined at an acute angle with respect to both the traveling direction and the width direction of the steel plate. Since the abrasive material is projected onto the advancing steel plate, by controlling the number of operating centrifugal projectors according to the width of the steel plate, it is possible to reduce unnecessary projection of the abrasive material, and also to reduce the number of abrasive materials It is possible to reduce energy loss due to collisions, and to greatly improve the overall abrasive projection efficiency, making it an extremely significant contribution to the industry.

[Brief explanation of the drawing]

FIG. 1 is a front view illustrating the surface treatment of a steel plate by the method of the present invention, FIG. 2 is a side view, and FIG. 3 is a front view illustrating the surface treatment of a steel plate by the conventional centrifugal projection treatment method. be. (l): Rope plate, (2): Centrifugal projection device, (3): Abrasive material. Patent applicant: Mitsubishi Heavy Industries, Ltd. Shinto Kogyo Co., Ltd. Representative: Akira Shima
Part time Watanuki Tatsu Rikai Yama Zero
Text Husband 7: Appeal 3: Timber Forest Figure 1!

Claims (1)

[Claims] In a steel plate surface treatment method in which scale is removed from the surface of a steel plate by projecting abrasive material from the projection ports of multiple centrifugal projection devices toward a steel plate advancing, the abrasive material projected from the projection ports of each centrifugal projection device is A method for surface treatment of a steel plate, characterized by projecting at an acute angle with respect to both the traveling direction and the width direction of the steel plate.