JPS5838604A - Descaler for steel strip - Google Patents

Abstract

PURPOSE:To obtain a titled device which can deal with high speed removal of scale from the surfaces of steel strips and has good efficiency by providing plural centrifugal projectors for abrasive materials above and below via separators on both sides along an approximately vertical by-pass line on the midway of a conveying line for steel strips. CONSTITUTION:A hot rolled steel strip 1 is fed by a tension imparting device 6 into a frame body 8, passes through a by-pass line, emits from the body 8 and is fed with a tension imparting device 7. In the pass line in the body 8, abrasive materials 15 are projected by centrifugal projectors 9a-14a, 9b-14b to the front and rear surfaces of the strip 1, whereby scale is removed. Here, the mutual interferences of the materials 15 from the projectors 9a-14a, 9b- 14b arrayed in a vertical direction are prevented by separators 16a-19a, 16b- 19b, and act effectively upon the strip 1 by each projector.

Description

[Detailed description of the invention] The present invention relates to an apparatus for removing scale from the surface of a steel strip.

Scale (oxide film) adheres to the surface of the steel strip that is produced during hot rolling, but it is necessary to remove this scale in order to perform the subsequent cold rolling without any problems. .

Pickling methods and fluid honing methods are known as methods for removing scale from the surface of steel strips.

In the pickling method, scale is removed by a chemical reaction by running the strip through a pickling tank containing hydrochloric acid at a temperature of 75 to 95'C for about 25 to 30 seconds.

In recent years, there has been an increasing demand for faster compression grinding, continuous use with cold pressure grinding machines, and non-polluting methods, but the pickling method requires extensive equipment due to descaling time constraints. As a result, it is becoming impossible to meet the above demands.

In the fluid honing method, abrasive material or abrasive material slurry is accelerated with high-pressure water and injected onto the steel strip surface i1, and the energy is used to remove scale.

However, Jin's method has many problems, such as requiring a large amount of energy to pressurize the water, and requiring a large amount of equipment cost and a large equipment area for the slurry sublayer equipment.

On the other hand, J conventional stainless steel plate t) *R annealing pickling equipment #
i. As a pretreatment for pickling, a surface treatment device using a centrifugal force projection device is employed. This centrifugal force projection device uses centrifugal force to spray abrasive material onto stainless steel plates! f
Toshi is a device that performs surface treatment by f1K projection, and #i is the above-mentioned surface treatment device.

Since the O layer speed of the stainless steel plate is as slow as 30-508/win, the stainless steel plate is run horizontally, and one or two centrifugal force projection devices are installed on each side of the stainless steel plate.

Since the above-mentioned nine conventional methods for removing scale from the surface of a steel strip obtained by hot rolling have problems that are difficult to solve, it has been considered to use the above-mentioned surface treatment equipment to remove scale. .

However, the surface treatment equipment mentioned above has a TTM speed change of 20
It is difficult to apply this method to the removal of scale from steel strips at high speeds of 0 to 400 turns/1n. For example, in order to adapt to high-speed steel strip processing, it is necessary to use multiple centrifugal force projection devices at one time, but in this case, mutual interference of the abrasive materials causes a reduction in cleaning efficiency. Situations arise.

The present invention has been made in view of the above-mentioned current situation, and an object of the present invention is to provide a descaling device that can cope with scale removal and is highly efficient.

The structure of the present invention to achieve the above object is to form a pass line in the middle of the steel strip conveyance line to detour the steel strip in a substantially straight direction, and to grind both sides of the steel strip while passing through this pass line. A number of centrifugal force projecting devices for projecting the abrasive material are arranged along the pass line in a number of KII stirrups on both sides thereof, and a separator is provided between the centrifugal force projecting devices adjacent in the vertical direction to prevent interference of the abrasive material. It is characterized by

EMBODIMENT OF THE INVENTION Hereinafter, the descaling apparatus 1 according to the present invention will be described in detail based on an embodiment shown in the drawings.

FIG. 1 shows a schematic configuration of an embodiment. A pass line is formed in the middle of the conveyance line that feeds the steel strip 1 horizontally. This pass line consists of the direction of the strip being fed horizontally (1t)--the deflector (4-2) which changes the direction of the strip vertically upward. The orientation of the steel strip 1 that is fed upward in the vertical direction; the deflector roll 3 that is oriented in the horizontal direction;
Deflector roll 4 that is enviable for the heat treatment of the horizontally oriented steel strip 1 and the horizontally oriented steel strip 1 that is sent to the lower rack.
It is formed by a deflector row x5 that changes the zero thickness 11 horizontally and returns it to the conveyance twin. In addition, before and after this pass line, there is a tension applying device 6.7 that applies a force to the steel strip lK11.
is provided.

The pass line is the upper two deflectors 3.4
(except for the frame sK).

On both sides of the steel strip 10 pass line in this frame 8,
Centrifugal force projection devices 9a, 10a for surface cleaning.

11m, 1! Turtle, 13ae 14a (hereinafter 9a-14
(abbreviated as "m") and back ■Centrifugal force projection device 9b for cleaning, Rob
, llb, 12b, 13b, 14b (hereinafter 9b to 14
(abbreviated as m+) are arranged inside each other. The arrangement may be staggered. These centrifugal force projection devices 9a to 141 and 911 to 14 rotate once in the direction of the arrow in the figure, respectively, and project the abrasive material 15 onto the front and back surfaces of the steel strip 1 using the centrifugal force. Abrasive materials from 15 companies are continuously supplied by a feeder, one of which is shown in the figure. The direction of projection of the abrasive material 150 is normally perpendicular to the traveling direction of the steel strip 1, but in Figure 1jIl it is shown opposite to the flow of the steel strip 1 to make it easier to spread.

(adjacent in the vertical direction) centrifugal force throwers 719 a a 10
m% 1eas 11alla% lla, 13a
Leap, isa.

Between 14m and 9), 10b, 10b, llb leap, 12
b, 11b, 131), 14t+l1aK is the separator 11 for preventing mutual interference of the abrasive material 1s.
a e 17' a 1 g a #1
fJ & (hereinafter abbreviated as 1lla to lea) and 16b
.

17, 18m and l1b (hereinafter abbreviated as 1611 to 1911) are provided. Separator 1lia~19&
and 1-b to 1911 slope downward from the bus lie/nearby side to the side, and then 11ki directly downward at 0jIl.
In addition, each separate IO is equipped with a centrifugal force projection device.

In the figure, the snow 0.31 Hiro grinding material IS is 2 m-2 on the deflector.
．． It is a rounded copper that prevents IK. Further, a round hopper 22 is connected to the lower part of the frame 80 for collecting the used abrasive material IS. By hopper 22■1
The used 041tl #15 is sent to the abrasive material collection facility (not shown) installed adjacent to the scissors device.
It is separated from the scale, collected, and sent to the centrifugal force projection device again (by the feeding device).

The steel strip 1 that has been compressed by heat compression passes through an unwinding machine, a welding machine, and an accumulator on the inlet side, and then is fed into a frame 8 by a tensioning device 6, and is used for detouring. It exits from the frame 8 through a pass line, passes through a tensioning device 7, passes through a washing device, a dryer, a steel strip storage device, etc., and is wound up into an MR winding machine after oiling. At the pass line in the frame 8, a centrifugal force projection device 9a is provided on both the front and back sides of the steel strip l.
The abrasive material 15 is projected onto 141 and 9b to 14'b to remove scale. At this time, centrifugal force projection devices 9 a to 14 a s 9 b to 1 arranged in the vertical direction
The presence of the separators 16a to 19a and 16b to 1G1a prevents the abrasive materials 1s from 4b from interfering with each other, and effectively acts on the strip steel IK with each centrifugal force projection device. Specifically, separators 14a to 1a and 16
'b~lll' Without b, the two-stage i centrifugal force projection device l
oa.

10b, 13m, 13b, bottom centrifugal force projection device 9a
, 9b, 141L# The cleaning effect of 14b is 1/
, , 1/, or less, and the energy loss and equipment cost loss will be enormous. In addition, the separator 16a
In order to further enhance the effects of 19a and 16b to 191), a lip may be attached to the tip of the separator, a small diameter roll may be used with a tb, or an air purge may be performed.

FIG. 2 shows another embodiment of the descaling apparatus according to the present invention. This equipment is equipped with a pre-processing equipment 23 for performing pre-processing processes such as tension, descaling and light pressure of 1 g on the conveyance line on the inlet side of the frame 8 of the complete descaling equipment as shown in the diagram. There are many ways to improve the descaling effect of the descaling device IK. The rest of the configuration is the same as the previous embodiment, so the explanation thereof will be omitted.

According to Jin's apparatus, the pretreatment equipment 23
The number of centrifugal force projection devices O in the descaling device I can be reduced by 30 to 50, and the running cost can be reduced.

Fig. 3 shows another example of this equipment in the company history. This equipment is one in which a pickling tank 24 is provided on the conveyance line on the exit side of the frame 8 in the descaling equipment shown in Fig. 1. It is used for processing special steels that are difficult to scale, and when a strict 11-sided finish is required for l#. As the pickling method, hydrochloric pickling for 15 seconds or less is employed. It goes without saying that a cleaning tank and a dryer are provided on the outlet side of the pickling tank 24.

Normally, the relationship between the descaling rate and the projection density when no pretreatment is performed is as shown in Figure #1114.

From this figure, it is clear that the ninth abrasive material O, which performs complete descaling, has an eta of about 100 Kt/d. Also, at a projection density of 30 to 50-/-, descaling of about 70 is possible, and KIf
i70*t) A must for descaling! It can be seen that more than twice the energy is required. To eliminate this defect, the pipe is pickled with hydrochloric acid using the equipment shown in Figure 9 #I3. With conventional hydrochloric pickling, the descaling time (immersion time during pickling) is 30 seconds for normal hot rolled steel sheets, but with this device, it has been found that descaling is possible in less than 1 second. There is. However, when strict conditions are required for the finish of a descaled steel plate, a round blade that performs the final finishing by pickling has the advantage of yielding good results. still,
In FIG. 3, the pickling tank 24 has a horizontal arrangement, but it may be arranged vertically so that it can be immersed in an acid solution or sprayed with it.

As described above in detail with reference to the embodiments, the descaling device according to the present invention prevents the mutual interference of the abrasive materials supplied from a large number of centrifugal force projection devices. The material acts effectively on the steel strip, making it possible to efficiently remove scale from the steel strip. In addition, since this equipment extends perpendicularly to the conveyance line, there is no need to take up an installation area as large as in the past.

[Brief explanation of the drawing]

Schematic diagram of the example, Figure 2 Schematic diagram of the embodiment of Hiro et al. , 19a to 14m and 9b to 14b are centrifugal force projection devices, 16a to 19m and 1611 to 19b #i separators, and 23 are pretreatment equipment. 24 is a pickling tank, and 2 is a descaling device.

Claims (1)

[Claims] A pass line is formed in the middle of the steel strip conveyance line to detour the steel strip in a substantially perpendicular direction, and a centrifugal force projection device that projects an abrasive onto both sides of the steel strip that is passing through the pass line is attached to the pass line. A strip steel descaling device characterized in that a number of centrifugal force projecting devices are arranged along both sides of the strip steel, and a separator is installed between vertically adjacent centrifugal force projection devices to prevent interference of abrasive material.