JPH0525669A - Surface treating device for steel sheet - Google Patents

Abstract

PURPOSE:To provide the surface treating device for a steel sheet for efficiently treating the steel sheet with a treating liquid, such as pickling soln. CONSTITUTION:Plural pieces of upper nozzles 14 and lower nozzles 16, the ends on one side of which face both surfaces of the traveling steel sheet S. The ends on the other side of these upper nozzles 14 and lower nozzles 16 are communicated with resonance tubes 13. Pulsation oscillators 15 are mounted to the resonance tubes 13 and the pressure of gas is pulsated by the oscillation of the pulsation oscillators 15 to intermittently inject jets L1 from the nozzles. The jets are brought into collision against the surfaces of the steel sheet S to sufficiently thin the surface boundary areas, by which the surface treating effect is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel sheet surface treating apparatus for pickling and degreasing the surface of a steel body.

[0002]

2. Description of the Related Art FIG. 4 is a vertical sectional view of a jet pickling tank for continuously pickling steel strip according to the prior art, and FIG. 5 is a sectional view taken along the line V--V. As shown in both figures, container 0
1 has a box-like shape, and the surface thereof is pickled by the acid solution L jetted from the nozzle header 02 while the strip steel S being conveyed is traveling (moving in the left-right direction in FIG. 4). ing. A part of the tank bottom surface 03 of the container 01 is generally formed to be high in the traveling direction of the steel strip S, and a plurality of skids 04 supporting the steel strip S are provided on the raised tank bottom portion 03. Is provided. Further, in the container 01, a plurality of drainage ports 05 are formed along the traveling direction of the steel strip S, and before and after the traveling direction of the steel strip S passes through the drainage passages 06 and 06, Collection chamber 0 for storing the discharged pickling solution L
7,07 are formed. Drain pipes 08 and 08 are attached to the liquid collecting chambers 07 and 07, respectively.
Reference numeral 8,08 is connected to an acid solution tank (not shown) which stores the pickling solution L, and the pickling solution L is sent to the nozzle header 02 by the environmental device and is again subjected to the acid treatment.

[0003]

In the pickling apparatus according to the prior art described above, the mass transfer phenomenon between the pickling solution L and the steel sheet S, which governs the pickling effect, is caused by the movement of the steel sheet S. It was promoted only by the stirring effect of the relative speed with the pickling solution L and the liquid flow speed from the nozzle header 02 attached only to the inlet / outlet of the container 01. There is a demand to further improve the acceleration effect, shorten the pickling time, and speed up the treatment. Therefore, a means for disposing the nozzle header 02 in many places other than the inlet / outlet of the container 01 has been proposed. However, a circulating device (not shown) such as a pump, a pipe, a valve, etc., for circulating the corrosive pickling solution L is required, which makes the manufacturing cost expensive and the pump power is large. Therefore, there is a problem that the running cost becomes high.

[0004]

The structure of a steel sheet surface treating apparatus according to the present invention for solving the above-mentioned problems is a steel sheet surface treating apparatus for treating a surface of a steel sheet while traveling while immersing the steel sheet in the treatment liquid. A container in which the steel plate travels while holding the treatment liquid, a plurality of nozzles penetrating the container, the tip opening of which faces the surface of the steel plate and is immersed in the treatment liquid, and the other end of the nozzle. And a pulsation oscillating device for pulsating the pressure of the gas in the resonance tube.

[0005]

In the above structure, during the surface treatment of the steel sheet, the pressure of the gas in the resonance tube is periodically changed (pulsated) by the pulsation oscillating device to raise and lower the water column of the treatment liquid in each nozzle to jet the treatment liquid. Is intermittently ejected from the nozzle to collide with the surface of the steel sheet, and the concentration boundary layer is thinned by stirring the liquid flow on the surface of the steel sheet, thereby improving the treatment effect. It should be noted that the gas in the resonance tube is in a resonance state, energy loss due to the gas flow is minimized, and high pressure fluctuation is obtained.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the steel strip pickling apparatus according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a main part of a steel sheet surface treating apparatus according to this embodiment, and FIG. 2 is a sectional view taken along the line II-II of FIG. As shown in these drawings, a steel plate surface treatment apparatus 10
Is to fill the inside of the container 11 with the pickling solution L and to subject the surface of the steel strip S traveling on the skid 12 arranged at the tank bottom 11a to pickling.

In the vicinity of the surface of the steel plate S running in the container 11, the resonance tube 1 penetrates the tank upper portion 11b of the container 11.
A plurality of upper end opening portions 14a of the upper nozzles 14 communicating with the nozzles 3 are arranged so as to face each other. That is, in this embodiment, a plurality of upper nozzles 14 communicating with one resonance tube 13 are provided.
Are provided in three rows in the traveling direction of the steel strip S (FIG. 1).
(See FIG. 2), the strips S are provided in nine rows in the width direction (see FIG. 2), and the pickling solution is jetted onto the surface of the steel sheet. The resonance tube 13 is provided with a pulsation oscillating device 15 for periodically pulsating the air in the resonance tube 13 (see FIG. 2).

On the other hand, in the vicinity of the lower surface of the steel strip S traveling in the container 11, as with the upper nozzle 14, the tip opening 1 of the lower nozzle 16 penetrating the tank bottom 11a and communicating with the resonance pipe 13.
A plurality of 6a are arranged so as to face each other. The lower nozzle 16 has a curved tubular shape in order to raise and lower the water column L ₂ therein and prevent the pickling solution from flowing into the resonance tube 13.

As shown in FIG. 2, cylinders 17 are attached to both ends of one resonance tube 13 which the upper nozzle 14 and the lower nozzle 16 communicate with each other. The piston 18 is movably positioned, and the piston 18 is connected to the tip end side of a connecting rod 20 whose base end side is connected to the crankshaft 19. Also,
The crankshaft 19 is connected to a motor (not shown) for rotating the crankshaft 19, and a crank mechanism constituted by the cylinder 17, the piston 18, the connecting rod 20, the crankshaft 19 and the like rotates the motor to rotate the piston 18 The pulsation device 15 is converted into the reciprocating motion of (1), and the pressure fluctuation is generated in the resonance tube 13 accordingly.

Next, the procedure for pickling steel strip with this apparatus will be described. The steel strip S is immersed in the pickling solution L in the container 11 and run while being supported by the skid 12. And
The pulsating oscillator 15 periodically changes (pulsates) the air pressure in the resonance tube 13 so that the upper nozzle 14 and the lower nozzle 1
The water column L ₂ of the pickling solution L in 6 is moved up and down, and the jet stream L _{1 of the} pickling solution is fed from the tips of the upper nozzle 14 and the lower nozzle 16 to the steel strip S.
By intermittently colliding with the upper surface and the lower surface of the to thin the concentration boundary tank on the surface, the pickling effect is improved. Figure 3
Is the effective length l of the resonance tube 13 = about 8.5 m, and the oscillator 15
The results of the experiment by the oscillation frequency = 20H _Z of, which indicates to expand the resonance tube 13, the air pressure inside varies as shown by the operation of the oscillator 15.
As shown in the figure, the length l and the oscillation frequency of the resonance tube 13 can be set by the sound velocity of the air in the resonance tube 13 to obtain the resonance state in the resonance tube 13, and the energy due to the air flow can be obtained. It is possible to minimize loss and obtain high pressure fluctuation. In addition, in the present embodiment, an example is shown in which the upper and lower surfaces of the steel plate S that horizontally pass are simultaneously processed, but the present invention is not limited to this and, for example, whether the steel strip S is horizontal or vertical in the pass direction, Independent treatment of each side of steel is also possible.

[0012]

As described above with reference to the embodiments, in the surface treatment apparatus for steel sheet according to the present invention, the nozzle for injecting the surface liquid of the traveling steel sheet, the resonance tube for pulsating the pressure of the gas inside, and the oscillating device are provided. Since the jet flow is intermittently ejected from the nozzle and collides with the surface of the steel sheet to make the surface boundary layer sufficiently thin, the surface treatment effect is improved and the treatment time can be shortened. .. Therefore, the traveling speed of the steel sheet or the length of the processing container can be shortened. Further, since a circulating device for the processing liquid is not necessary, the manufacturing cost and running cost of the device can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic view of a steel plate surface treatment apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II of FIG.

FIG. 3 is a graph showing fluctuations in air pressure in the resonance tube.

FIG. 4 is a vertical sectional view of a conventional pickling apparatus.

FIG. 5 is a sectional view taken along the line VV in FIG.

[Explanation of symbols]

 10 Steel Plate Surface Treatment Device 11 Container 12 Skid 13 Resonance Tube 14 Upper Nozzle 15 Pulsation Oscillator 16 Lower Nozzle S Strip Steel L Pickling Solution

Front page continuation (72) Inventor Yuji Furusawa 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture Mitsubishi Heavy Industries, Ltd. Hiroshima Research Laboratory (72) Inventor Shigeo Itano 4-22 Kannon-shinmachi, Nishi-ku, Hiroshima Prefecture Mitsubishi Heavy Industries Ltd. Hiroshima Research Center

Claims (1)

Claim: What is claimed is: 1. A surface treatment apparatus for a steel sheet, which is for treating a surface of a steel sheet while immersing the steel sheet in a treatment liquid while traveling, and a container for holding the treatment liquid and in which the steel sheet travels. A plurality of nozzles penetrating the container, the tip opening of which faces the surface of the steel sheet and is immersed in the treatment liquid; a resonance tube which is connected to the other end of the nozzle and which is filled with gas; And a pulsation oscillating device that pulsates the pressure of the gas.