JPH0446625A - Method and device for descaling material to be rolled - Google Patents

Abstract

PURPOSE:To allow the de-scaling of little variation and a good performance by providing the spray header in the upper/lower directions of the hot rolling line and making constantly the distance of the spray header nozzle to the material to be rolled and the angle of the jet high pressure water from the nozzle against the material to be rolled. CONSTITUTION:The de-scaling is executed by jetting the high pressure water to the material to be rolled running on the carrying roll 5 from the nozzle 3 of the spray header tube 2 set on the upper and lower directions of the hot rolling line. In this time, the spraying distance from the nozzle 3 to the material to be rolled 1 is kept constantly by elevating and descending the header tube 2 with the hydraulic cylinder 11 corresponding to the material to be rolled, and also the angle of the high pressure water to the material to be rolled is made constant by rotating the header tube 10 with the motor 10. Therefore, the de-scaling without variation can be executed in spite of the state of waviness of the material to be rolled.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method and apparatus for descaling rolled material, and more particularly to a descaling method using high-pressure water spray in a hot rolling line and an apparatus therefor.

In conventional hot rolling lines, scale is generated on the surface of the rolled material in the heating furnace or during the transportation of the rolled material, and if this scale is not removed, the scale will embed in the base metal during rolling, resulting in poor surface quality. Since this can cause mechanical strength problems, it is usually removed using high-pressure water spray when fishing on a boat.

Hereinafter, the method for descaling the rolled material will be further explained in detail. Regarding the conventional technology, for example, 3rd edition edited by the Japan Iron and Steel Institute, published in 1980 [For Steel Handbook (1) Rolling Foundations/Steel Plate J
P382-383 include a method of descaling by spraying high-pressure water of 100-150 klcl culm onto the material to be rolled from a header pipe via a nozzle at a position immediately before rolling.

The structure of a general header will be explained with reference to FIGS. 3(a), (b), and (c).

FIG. 3A is a side view of the rolling material 1, in which the material to be rolled 1 moves on the conveying roller 5 in the direction of the arrow from left to right.
Descaling is performed by high pressure water injected from the header pipe 2 via the nozzle 3. According to research by the present inventors, the spray angle θ of high-pressure water sprayed onto the rolled material 1 is preferably 70” to 80” as shown in FIG.
If it exceeds 0°, there is a problem that the exfoliated scale will scatter, and it cannot be used even if the collision force is large. Also, 70°
If it is full, the collision force will be reduced, resulting in poor efficiency. Therefore, for boat fishing, the spray angle θ is set to about 75°. (B)
is a front view of the header tube 2 viewed from the board width direction.

A nozzle 3 with a high-pressure water flow angle φ (normally about 30', and if it is wider than the opening, a problem will occur with collision force) is installed in the header pipe 2 at a nozzle pitch a of, for example, about 80 to 13011 m,
In addition, the header pipe 2 has a spray height,
, 12 positions. (c) is (b) A
It is an explanatory diagram taken from direction A, and shows a spray position 6 when spraying is applied onto the rolled material 1. The twist angle α is to prevent interference between sprayers and is usually 1.
It is about 5°. Further, although the lap ld is usually about several tens of mm, if the lap amount d is increased, the lap portion 4 will have an unnecessary cooling effect, which is not preferable in terms of the material. Furthermore, the amount of high-pressure water required also increases, which is unfavorable in terms of energy consumption. In addition, if the amount of wrap d is made small (or not wrapped), there will be problems such as scale remaining in the wrap portion 4, resulting in a defective product.For the spray height 1, .5, the shorter is the middle value. It is clear that the collision force per area is strong, as supplementary information is shown in the graph of FIG.

However, in the conventional general descaling method as described above, the spray height l+, 12 is fixed, so it is not possible to deal with the thickness and waviness of the rolled material 1, so the descaling method must be adjusted from time to time. There is a problem that scalability is weak or strong. For example, if the rolled material 1 is greatly undulated as shown in the side view of Figure 5 (A), the spray angle θ is small in the Δ section, which is a problem, and the spray is too small as shown in (C). Since it no longer wraps, the non-271st part remains on the scale.

In addition, in the side view of (a), part B is sagging in the opposite direction to part A, and the angle θ becomes too large, causing scale to scatter in the direction of material progress.According to the front view of (b), 12 is the design value. Since the width is wider than that, descaling performance becomes worse. Furthermore, since the wrap 11d becomes too large, there is a problem in that the wrap portion 4 becomes overcooled.

Problems to be Solved by the Invention The present invention aims to solve the above-mentioned problems. Specifically, it improves the conventional descaling method and its equipment, and provides a descaling method with good descaling performance and consistent descaling force. The purpose of this study is to propose the g-position.

Although it is a means to solve the problem, the present invention is suitable for running on a hot rolling line. ] When descaling the rolled material with high-pressure water before rolling, a spray header is installed in the vertical direction of the hot rolling line so that it can be raised and lowered and rotated along the central axis. The spray header nozzle is moved up and down to maintain a constant spray distance from the rolled material, and the high-pressure water sprayed from the spray header nozzle is rotated to maintain a constant angle of 11 to the rolled material. And also,
In a descaling device using high-pressure water for rolled materials running on a hot rolling line, a header pipe equipped with nozzles installed at a predetermined interval in the vertical direction on the line and along the central axis of this header pipe are used. The present invention is characterized in that it is composed of an elevating device that connects the header pipe to a rotating device and moves the header pipe and the rotating device up and down integrally.

Hereinafter, the structure and operation of the means of the present invention will be explained in detail with reference to the drawings.

Note that FIG. 1 is an explanatory side view of an example of an apparatus used in carrying out the present invention, and FIG. 2 is an explanatory diagram of a scale removal method according to an embodiment of the present invention. Figures 3 (a), (b), and (c) each show the structure of a conventional spray header, where (a) is a side view, (b) is a front view, and (c) is the A-A direction of (b). FIG. 4 is a graph showing the relationship between the spray angle and the impact force per unit area, and FIGS. The figure shows a descaling method for a rolled material with (a) a side view, (b) a front view, (
C) is an explanatory diagram of the spray state of parts A and B in (A), and FIG. 6 is a graph showing the relationship between spray height and collision force per unit area.

Reference numeral 1 indicates the material to be rolled, 2 indicates the header pipe, 3 indicates the nozzle, 4 indicates the wrap section, 5 indicates the conveyance roller, 6 indicates the flushing position, 7 indicates the water pipe, 8 indicates the bearing box, 9 indicates the reducer, and 10 indicates the motor. , 11 is the hydraulic cylinder, a is the nozzle pitch, φ is the spread angle, l,
12 is the spray height, θ is the spray angle, α is the twist angle, d is the amount of overlap, and b is the non-sprayed portion.

Reference numeral 20 in FIG. 1 indicates a descaling device, and this descaling device includes a header pipe 2 equipped with nozzles 3 provided at predetermined intervals in the vertical direction on the hot rolling line, and a central axis of the header pipe. The header pipe is connected to a rotating device that rotates along the header pipe, and an elevating device that integrally raises and lowers the header pipe and the rotating device.

A plurality of nozzles 3 for spraying are arranged in a header pipe 2, and the header pipe 2 is configured to be rotatable and fixed by a bearing box 8, and the header pipe 2 is rotated by a motor 10. , the header pipe 2 is actually rotated via a speed reducer 9. The lifting device is Mota 10. It consists of a hydraulic cylinder 11 that supports all of the reducer 9, bearing box 8, and header pipe 2, and the header pipe 2 is configured to be able to move up and down by the hydraulic cylinder 11.

Although FIG. 1 only shows the upper header pipe 2 for ease of understanding, it goes without saying that the lower part also has a similar structure. Figure 2 shows a method for descaling a rolled material with large undulations. For a rolled material 1 with large undulations, the lower header pipe 2 is descaled by a hydraulic cylinder 11 in order to keep the spray height constant. The tube 2 is raised from the position indicated by the dotted line and rotated counterclockwise to the position indicated by the solid line where the spray angle θ is kept constant. If high-pressure water is injected from the header pipe 2 while rotating the material, even if the material to be rolled has a large undulation, it can be descaled by the high-pressure water.

Note that the operation of the header pipe 2 as described above may be performed manually by the operation work 0, but this method allows the movement to be defined uniquely geometrically, so that the undulations and the rolled material can be controlled. Automatic contouring based on the calculation 1L can be easily realized by converging information on the transport speed of 1 using a sensor.

According to the present invention, the header pipe 2 can be moved up and down to a height of l,,l? can be kept constant at all times, and since the header pipe 2 can be made freely rotatable and the swivel angle θ can be kept constant, it is possible to eliminate defects such as scale residue, and also to reduce variations. descaling is possible.

Example: Using the equipment shown in Fig. 1 to raise and lower the header pipe using the rolled material having the undulations shown in Fig. 2, the spray angle was adjusted to 75°.
When the header pipe was rotated and high-pressure water was injected to descale the material, the surface spray of the material to be rolled was completely descaled without any variation, and the rolling process was improved compared to the conventional method. Later surface defects were reduced by more than half.

, Effects of the Invention 2> As explained in detail above, the present invention provides spray headers in the vertical direction of the hot rolling line when descaling the rolled material running on the hot rolling line with high pressure water before rolling. The spray header is raised and lowered to maintain a constant spray distance from the spray nozzle to the rolled material, and spray is sprayed from the spray header nozzle. The feature is that the high-pressure water is rotated so as to maintain a constant angle with respect to the rolling water, and in a descaling device using high-pressure water for rolled materials running on a hot rolling line, A header pipe equipped with nozzles provided at intervals of It is characterized by

Therefore, when descaling the material to be rolled using high-pressure water, the header pipe can be raised and lowered and rotated freely, making it possible to perform descaling without variation regardless of the waviness of the material to be rolled. By applying the present invention to actual operation,
It has become possible to reduce surface defects due to surface spray bite to less than half compared to the conventional example.

[Brief explanation of the drawing]

FIG. 1 is an explanatory side view of an example of an apparatus used in carrying out the present invention, FIG. 2 is an explanatory diagram of a scale removal method according to an embodiment of the present invention, and FIG. (B) and (C) respectively show the structure of a conventional spray header, where (A) is a side view, (B) is a front view, and (C) is (B).
Fig. 4 is a graph showing the relationship between spray angle and collision force per unit area, Fig. 5 (a)
, (B) and (C) respectively show the conventional method of descaling a rolled material having undulations, and (A) is a side view;
(b) is a front view, (c) is an explanatory diagram of the spray state of part A and part B of (a), and Figure 6 is a graph showing the relationship between spray height and collision force per medium area. be. Code 1... Pressure tvi 2... Header pipe 3... Nozzle 4... Wrap section 5... Conveyance loaf 6... ... Spray position 7 ... Water pipe 8 ... Bearing box 9 ... Speed reducer 10 ... Motor 11 ... Hydraulic cylinder a ...Nozzle pitch φ...Spread angle! ,,12...Spray height θ...Spray angle α...Twist angle d...Wrap amount b...Non-spray part No. Figure 3 * Figure 4 square nl, θ ji) -15. Figure 5

Claims (1)

[Scope of Claims] 1) When descaling a material to be rolled running on a hot rolling line with high-pressure water before rolling, a spray header is moved up and down in the vertical direction of the hot rolling line and is centered. The rolled water is provided rotatably along an axis, and the spray header is raised and lowered so as to maintain a constant spray distance from the spray header nozzle to the rolled material, and the high-pressure water is sprayed from the spray header nozzle. A method for descaling a rolled material, characterized by rotating the material at a constant angle. 2) The method for descaling a rolled material according to claim 1, wherein the rolled material has a deformed portion. 3) In a descaling device using high-pressure water for rolled materials running on a hot rolling line, a header pipe equipped with nozzles provided at predetermined intervals in the vertical direction on the line and a central axis of this header pipe. What is claimed is: 1. A descaling device for rolled material, comprising: a lifting device connected to a rotating device that rotates along the header pipe, and an elevating device that raises and lowers the header pipe and the rotating device integrally.