JP3287758B2 - Rotary sealing method for strips such as steel plates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary sealing method for sealing a processing liquid in a processing tank for pickling or plating, for example, in the production of a steel sheet without causing surface scratches or the like on the steel sheet strip.

[0002]

2. Description of the Related Art In a processing tank for continuously picking and plating a steel sheet by passing the strip, the strip passes vertically through a lower end of the tank body. Since the vehicle travels, it is necessary to seal the penetrating portion to prevent leakage of the processing liquid. And since the strip is always running, the processing liquid often leaks even as an accompanying flow along the surface of this strip,
In this case as well, leakage of the processing liquid must be prevented.

As a seal for preventing such a leakage of the processing liquid, a pair of dam rolls are rotatably arranged with a pass line interposed therebetween, as described in, for example, Japanese Patent Application Laid-Open No. Hei 5-331595. There is a configuration in which both ends in the axial direction of the dam roll are sealed to the outside with a seal ring, and a seal plate for contacting and sealing the peripheral surface of the dam roll is arranged.

The seal device described in this publication is based on a conventionally known rotary seal,
By adding a seal ring and a seal plate, a more preferable sealing function can be achieved.

[0005]

As for the pair of dam rolls disclosed in the above publication, similarly to the conventional rotary seal, a rotatable roll is pressed against both sides of the strip and the strip is passed through while narrowing the pressure. It is going to go. And the sealing force to the strip surface can be increased almost in proportion to the narrow pressure between the rolls.

However, when the surface of the strip is narrowed by such a pair of rolls, the surface of the strip tends to be damaged. This is because, in the case of the sludge and the electrolytic bath, foreign substances such as electrodeposits are contained in the processing liquid, and these foreign substances may be caught between the surface of the strip and the roll. One cause. If the surface of the strip is scratched as described above, the quality of the strip is greatly reduced, so that the frequency of inspection and replacement of the sealing roll is increased, and the operation rate of the line is affected.

Further, when the strip is in a meandering state and passes through the sealing roll, the strip is narrowly pressed between the rolls, so that if the strip meanders in a direction swinging in the axial direction of the roll, the strip is narrowed. The strip in the pressed portion is passed without any degree of freedom in the thrust direction of the roll. Therefore,
As the strip passes between the rolls, the thrust force received from the rolls in the meandering direction is complicatedly entangled. Quality will be greatly degraded.

[0008] Further, not only the foreign material is caught, but also the contact between the strip and the roll peripheral surface causes the surface of the strip to be damaged. One reason for this is that the narrow pressure of the roll against the strip is maintained high to secure the sealing pressure, but the same applies when the strip passing speed and the roll peripheral speed do not match. The phenomenon occurs.

As described above, in a conventional treatment tank for pickling or plating, there is a problem that the surface of the strip is abutted with a sealing roll, so that surface flaws and wrinkles cannot be avoided.

The problem to be solved in the present invention is to provide a rotary sealing method capable of preventing the occurrence of surface scratches and wrinkles on the strip while maximizing prevention of leakage of the processing liquid.

[0011]

According to the present invention, there is provided a facility for passing the strip between a pair of seal rolls provided on at least one of an inlet side and an outlet side of a processing tank for continuously passing the strip, The gap between the peripheral surfaces of the seal rolls is set to be 0.3 to 2 mm larger than the plate thickness of the strip, so that the surface of the strip and the peripheral surface of the seal roll are in a non-contact relationship, and with respect to the traveling direction of the strip. The processing liquid is squeezed in a gradually decreasing space formed by the seal roll, and a thin film layer of the processing liquid in the processing tank is formed between the surface of these strips and the peripheral surface of the seal roll to form the processing liquid. A sealing force is generated against

In such a method, it is also possible to operate the seal roll by rotating the seal roll so as to adjust the rotation direction to the strip passing direction and to match the peripheral speed of the seal roll to the strip passing speed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a proper sealing property between the strip surface and the peripheral surface of the seal roll is provided so that the strip surface is not damaged while exhibiting sufficient sealing properties that can be endured as a practical technique. An interval is to be provided. In determining the interval, the present inventors conducted an experiment on the relationship between the strip plate thickness, the seal roll peripheral surface outflow, and the frequency of occurrence of scratches on the strip surface. As a result, data as shown in FIG. 1 is obtained. I was able to.

As can be seen from this figure, even if the seal roll does not contact the strip surface, the interval is preferably 0.3 to 2 mm larger than the plate thickness, preferably 0.5 to 1 m.
If the range is increased by m, the accompanying flow generated by the passing of the strip is narrowed between the seal rolls by the gradually decreasing space formed by the seal rolls in the traveling direction of the strip. That is, the flow path resistance increases and the outflow of the processing liquid can be suppressed.

As will be apparent from FIG. 2, which will be described later as an embodiment, the smaller the distance between the seal roll peripheral surfaces, the smaller the amount of the treatment liquid flowing out, but the less frequently the flaws occur on the strip surface. To increase. On the other hand, when the interval increases, the frequency of occurrence of scratches on the strip surface decreases, but the outflow of the processing liquid increases.

Accordingly, in the present invention, the minimum gap is set to 0.3 mm because the frequency of occurrence of scratches on the strip surface is high in the range of 0.3 mm or less from the relationship between the frequency of occurrence of the scratch on the strip surface and the gap. . Further, from the relationship between the processing solution outflow and the gap, if the gap is 2 mm or more, the processing solution outflow is large and impractical.
And

By setting the maximum and minimum values of such a gap, a thin film can be formed in the gap between the strip and the peripheral surface of the seal roll closest to the strip. The resistance to the leakage of the processing liquid in the processing tank can be provided. By rotating the seal roll, the formation of a liquid film on the surface of the seal roll is further promoted.

On the other hand, the gap between the strip and the seal roll does not bite even if foreign matter in the processing liquid invades, so that it is possible to prevent the surface of the strip from being damaged.
Further, since there is no restriction in the thrust direction by the seal roll, wrinkles do not occur even if the strip sways in the width direction.

Further, when the seal roll is driven to rotate at a peripheral speed corresponding to the traveling speed of the strip, the relative speed between the peripheral surface of the seal roll and the surface of the strip becomes zero, and even if the seal roll comes into contact with the surface of the strip, the surface of the strip is damaged. Is prevented from occurring.

[0020]

FIG. 2 is a longitudinal sectional view of a main part showing a seal structure to which the rotary sealing method of the present invention is applied.

In the drawing, an inlet 1a for a strip S is provided at the lower end of a processing tank 1 for pickling or plating, for example.
And a pair of seal rolls 2 and 3 for preventing leakage of the processing liquid from the inlet 1a together with the strip S are provided on the lower surface of the processing tank 1. The seal rolls 2 and 3 are housed in a dedicated chamber provided on the lower surface of the processing tank 1 as described in, for example, Japanese Patent Application Laid-Open No. Hei 5-331595 described in the section of the prior art, and are disposed in the axial direction. A seal ring may be interposed between the end face of the chamber and the inner wall of the chamber. And a pair of sealing materials 1
b and 1c are attached to the processing tank 1 and the seal rolls 2 and 3 are rotated by contacting the seal materials 1b and 1c, thereby forming the seal rolls 2 and 3 and the bottom wall of the processing tank 1. Is sealed.

The seal rolls 2 and 3 can swing around fulcrums 2a and 3a to change their positions as indicated by solid lines, broken lines and two-dot chain lines, respectively. A drive mechanism such as an electric motor is connected to these seal rolls 2 and 3 so that the seal rolls 2 and 3 can be driven to rotate at a peripheral speed that matches the traveling speed of the strip S. The connection with the drive mechanism is released by the means to enable free rotation.

The traveling direction of the strip S may be upward or downward in the figure. When traveling upward, the seal rolls 2 and 3 are driven to rotate in the direction of the solid line arrow in the figure and in the direction of the dashed line arrow when traveling downward. Is done.

Here, when the seal rolls 2 and 3 are at the positions indicated by the solid lines, the seal rolls 2 and 3 are arranged so as to have a gap with respect to the strip S. That is, the interval d of the gap on the line segment passing through the center of each of the seal rolls 2 and 3 is the thickness t + of the strip S + (0.3 to
2) mm. Naturally, the gap d of the gap changes depending on the thickness of the strip S, and the larger the thickness, the larger the gap d. For this reason, a suitable value is set according to conditions such as the plate thickness.

The setting of the distance d between the seal rolls 2 and 3 is based on the premise that the seal has sufficient sealing properties as a practical technique. Is inevitable. On the other hand, for example, when the strip S travels upward in the drawing, the seal rolls 2 and 3 rotate in the direction of the arrow shown by the solid line in the drawing, so that the processing liquid from the inlet 1a flows down along the surface of the strip S. Even if it does, it comes to come in contact with the peripheral surfaces of the seal rolls 2 and 3 and is pushed upward, so that it is possible to exert a resistance against the treatment liquid leaking through the gap as it is. Further, seal rolls 2 and 3 are provided on the upper end of the processing tank 1.
Is the figure which turned upside down from FIG. 1,
In this case, the processing liquid tends to rise as an accompanying flow attached to the surface of the strip S, but leakage upward is suppressed by the own weight of the processing liquid itself.

As described above, even if the seal rolls 2 and 3 are not in contact with the surface of the strip S and the pressure is narrow, the rotation of the seal rolls 2 and 3 and the use of the weight of the processing liquid allow the leakage of the processing liquid. Can be prevented to some extent.

In the present invention, if the relationship between the viscosity of the processing liquid and the distance between the seal rolls 2 and 3 and the surface of the strip S is appropriate, the surface of the strip S where the space is most narrowed can be treated. Is formed. This is intended to utilize the same phenomenon as the formation of a lubricating boundary layer film of lubricating oil in the field of lubrication, for example.

Further, the sealing rolls 2 and 3 are
The rotational speed is adjusted to the passing direction of the strips S, and the peripheral speed of the seal rolls 2 and 3 is further matched with the passing speed of the strip S, thereby promoting the formation of a liquid film on the surfaces of the seal rolls 2 and 3.

As described above, even if the seal rolls 2 and 3 do not narrow the strip S, if the gap is appropriate, the entrainment flow generated by the passage of the strip S will cause the entrainment flow between the seal rolls 2 and 3. By utilizing the fact that the flow path resistance is increased by squeezing and the formation of a thin film of the processing liquid, a seal descent that can be endured as a practical technique can be exhibited, and the desired processing by the processing tank 1 can be performed. Can be performed.

The rotary sealing method of the present invention has an important significance in that it has a certain sealing effect and also prevents the generation of scratches and wrinkles on the surface of the strip S. That is, since the seal rolls 2 and 3 do not come into contact with the strip S, even if foreign matter is contained in the processing liquid and enters the space between the strip S and the seal rolls 2 and 3, it is not caught. The occurrence of surface scratches on the strip S is prevented. Then, the seal rolls 2 and 3 themselves also rotate to remove the strip S from the seal materials 1b and 1c.
Since the processing liquid adheres in a thin film shape to the peripheral surface toward the side, even if the strip S comes into contact with the seal rolls 2 and 3, the occurrence of surface scratches is similarly prevented.

Further, the strip S is made up of the seal rolls 2 and 3
Therefore, even if the strip S oscillates in the axial direction of the sealing rolls 2 and 3, the force for restraining the strip S in the width direction is not applied. The generation of wrinkles in the thrust direction by the rolls 2 and 3 is also prevented.

The seal rolls 2 and 3 are driven to rotate, and have the same circumferential direction as the running direction of the strip S and a peripheral speed corresponding to the running speed. Is rotated, the relative speed between the strip S and the peripheral surfaces of the seal rolls 2 and 3 can be made zero. Therefore, the seal rolls 2, 3
Even if the strip S collides violently, slippage between the strips does not occur, so that generation of surface scratches can be more effectively prevented.

As described above, in the present invention, it is possible to achieve as its greatest object to reliably prevent the surface scratches and wrinkles of the strip S from occurring while securing the sealing property of the processing liquid necessary for practical technology. It is. For example, in a case where the strip S is continuously passed through these processing tanks in a facility in which a plurality of processing tanks are arranged, the strip S passes through a large number of seal rolls. And the shape is maintained well, and a high quality product can be obtained.

In this embodiment, the case where the strip S is passed vertically is described. However, the present invention is not limited to this, and the present invention is applicable to the case where the strip S is passed horizontally. Can be done.

[0035]

According to the present invention, the strip can be passed while maintaining the seal to the maximum by actively utilizing the formation of a thin film without narrowing the strip by the seal roll. And the like, and there is no restriction in the thrust direction by the seal roll, so that it is possible to reliably prevent the surface of the strip from being scratched and wrinkled.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between the strip plate thickness, the amount of liquid flowing out between seal roll peripheral surfaces, and the frequency of occurrence of scratches on the strip surface.

FIG. 2 is a schematic vertical sectional view of a main part showing a sealing of a strip by a seal roll to which the rotary sealing method of the present invention is applied.

[Explanation of symbols]

 1: treatment tank 1a: inlet 1b: sealing material 2: seal roll 2a: fulcrum 3: seal roll 3a: fulcrum S: strip

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C23G 3/02 C25D 7/06

Claims (2)

(57) [Claims] 1. A facility for passing a strip between a pair of seal rolls provided on at least one of an inlet side and an outlet side of a processing tank for continuously passing a strip, wherein a gap between peripheral surfaces of the pair of seal rolls is provided. The surface of the strip and the peripheral surface of the seal roll are set in a non-contact relationship by setting the thickness to 0.3 to 2 mm larger than the thickness of the strip, and the taper formed by the seal roll in the traveling direction of the strip A steel plate or the like that squeezes the processing liquid in a space to be formed and forms a thin film layer of the processing liquid in the processing tank between the surface of the strip and the peripheral surface of the seal roll to generate a sealing force against the processing liquid. Rotary sealing method of strip. 2. The strip of a steel sheet or the like according to claim 1, wherein said seal roll is a rotary drive type, and a rotation direction is adjusted to a direction in which said strip passes, and a peripheral speed of said seal roll is made to coincide with a passing speed of said strip. Rotary sealing method.