JPH02277755A - Method for controlling pass position of continuous hot dip metal coating and device for controlling pass position of strip - Google Patents

Abstract

PURPOSE:To eliminate the deviation in the excitation states of both electromagnet groups by adjusting relatively the neutral points of both the electromagnet groups and the pass position of a strip, thereby preventing the generation of the burn of the electromagnets of both the electromagnet groups. CONSTITUTION:Both the electromagnet groups 2, 3 of the device 1 for controlling the pass position of the strip are mounted by positioning the neutral point SP thereof on a preset pass line PL. Both wiping nozzles 22 are similarly mounted by aligning the intermediate position thereof to the pass line PL. The electromagnet groups 2, 3 are, therefore, not particularly excited for correcting the pass position of the strip S as far as the strip travels on the set PL. The energization of one of the electromagnet groups is consequently indicative of the deviation of the pass position of the strip from the pass line PL. The neutral point of both the electromagnets and the pass position of the strip S are thereupon aligned by moving the electromagnet groups in the thickness direction of the strip S or directly moving the strip in the thickness direction, by which the generation of the burn of the electromagnets by the continuous excitation is prevented.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is directed to a continuous hot-dip metal plating line in which a gas wiping method is used to continuously apply hot-dip metal plating to the surface of a strip, which is a belt-shaped object. A strip passing position control method for continuous hot-dip metal plating that stabilizes the running of the strip by suppressing it and correcting warping deformation along the width direction, and a strip passing position control device used to implement this strip passing position control method. It is related to.

[Conventional technology]

As shown in FIG. 10, the gas wiping method, which is widely used in continuous molten metal plating lines, involves a pair of wiping nozzles 22, 22 sandwiching a strip S that is continuously drawn out from inside the molten metal in the thickness direction. are arranged facing each other, and a slit-shaped ejection port is formed at the tip of the wiping nozzle 22 facing the front or back surface of the strip S over the entire width range of the strip S, so that the gas ejected from the wiping nozzle 22 Excess molten metal adhering to the surface of the strip S is wiped off, thereby controlling the thickness of the molten metal plating applied to the surface of the strip S to be uniform.

The uniformity of the amount of molten metal plating applied to the strip S by the gas wiping method used in this continuous molten metal plating line is as follows: 1. Improving the uniformity in the width direction of the gas ejected from the wiping nozzle 22; 2. Wiping gas Maintaining the pressure at an appropriate constant value, ■Wiping nozzle 2
This is approximately determined by maintaining the distance between the gas outlet No. 2 and the strip S uniform.

Among these three factors mentioned above, many improvements and proposals have been made for ■ and ■, and have been quite effective, but for the remaining factor ■, As shown in FIG. 11, the strip S pulled out from the molten metal K is warped in the width direction (C warp), and as the strip S travels, there is a wiping point where gas is sprayed from the wiping nozzle 22. This was not sufficiently improved due to the vibrations that occurred.

The inventor of the present invention has already proposed Japanese Patent Application No. 63-212034 as a technique for improving these phenomena.

The technology shown in this patent application No. 63-212034 is
As shown in the figure, a front side electromagnet group 2 and a back side electromagnet group 3 are arranged opposite to each other with the strip S sandwiched along the thickness direction immediately downstream of the wiping point along the running line of the strip S, and both magnets The group 2.3 is composed of a central electromagnet 2a, 3a facing the central part of the strip S, and two side electromagnets 2b, 3b facing both end parts of the strip S. By controlling the magnetic attraction force of each electromagnet, the C warp of the strip S is corrected and the wiping nozzle port (gas jet port) at the wiping point is
This is to maintain a constant distance between the surface of the strip S and the surface of the strip S, and to prevent vibration of the strip S at the wiping point.

Further, as another technique for improving the above-mentioned phenomenon, there is a technique disclosed in Japanese Patent Application Laid-Open No. 62-30865. The technique disclosed in Japanese Patent Application Laid-Open No. 62-30865 is such that a pair of snap rolls are provided at the point where the strip is pulled out from the molten metal to press the pulled out strip while shifting its position in the thickness direction. By controlling the degree of pressure applied to the strip by the rolls, the C warp that has occurred in the strip is corrected.

[Problem to be solved by the invention]

Although the technique disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 62-30865 can correct the C warp that occurs in the strip to a certain extent, the correction is by no means sufficient, and the strip at the wiping point It remained impossible to eliminate the vibrations.

On the other hand, the technology disclosed in Japanese Patent Application No. 63-212034 has the advantage of being able to sufficiently correct the C warp that occurs in the strip S, and also reliably suppressing the vibration of the strip S at the wiping point. For example, as shown in FIG. 9, the actual passing position of the strip S is from the neutral point sp of the front electromagnet group 2 and the back electromagnet group 3 set according to the path line PL to the back side. If there is a large misalignment amount Δl toward the electromagnet group 3 side, the front electromagnet group 2 will be in a state where it is constantly excited to align the passing position of the strip S with the neutral point SP, and as a result, all of the front electromagnet group 2 Otherwise, there is a problem that a part of it may become overheated and burn out.

The reason why the actual passing position of the strip S deviates from the pass line PL that is mechanically set in advance is that the plating process for the strip S is performed under an extremely high temperature environment.
Due to the inability to apply strong tension to the strip S to be subjected to high temperature treatment and the difference in the dimensions of the strip S,
This is due to the different shapes of the strips S in the stretched state.

The present invention was devised to solve the problems in the prior art described above, and the excitation state of the group of blue electromagnets changes in response to the mismatch between the neutral point of the group of blue electromagnets and the actual passing position of the strip. By focusing on this, we aim to eliminate bias in the excitation state of the blue electromagnet group by adjusting the neutral point of the magnet group relative to the passing position of the strip, thereby preventing burnout of the electromagnets in the blue electromagnet group. purpose.

[Means to solve the problem]

The means of the present invention for achieving the above object is such that the actual passing position of the strip is adjusted to the blue electromagnetic magnet by the magnetic attraction force on the strip of two groups of electromagnets arranged oppositely across the strip in the thickness direction after passing the wiping point. The electromagnets in one electromagnet group of the strip passing position control device are continuously energized for a certain period of time or more. The method is to move the blue electromagnet group and the strip relatively in a direction in which one of the electromagnet groups approaches the strip when the blue electromagnet group is moved closer to the strip.

In other words, when the electromagnets of one electromagnet group of the strip passing position control device are continuously excited for a certain period of time or more, the actual passing position of the strip is not the same as that of the blue electromagnet group positioned according to a preset path line. It is determined that the position has shifted from the neutral point toward the other electromagnetic surface group, and the blue electromagnet group and the strip are moved relatively,
The neutral point of the group of blue electromagnets is made to coincide with the actual passing position of the strip.

As a means for relatively moving the blue electromagnet group and the strip in the direction in which one electromagnet group approaches the strip,
The method of directly moving the group of blue electromagnets without changing the actual passing position of the strip, and the strip withdrawal position control device that changes the withdrawal position of the strip from within the molten metal in the direction of the thickness of the strip, allow the strip to be easily moved. There is a method of directly moving the actual passing position.

In addition, as a means for implementing the method of directly moving the group of cyan electromagnets, it is necessary to have a bogie rail frame that is movable in the thickness direction of the strip at a position immediately after passing the wiping point, and to have a strip on this bogie rail frame. The strip has a front side electromagnet group and a back side electromagnet group that are assembled oppositely across the strip from the thickness direction and applies a magnetic attraction force to the strip, and has a shift source that moves the bogie rail frame in the thickness direction of the strip. .

The blue electromagnet groups in the strip passing position control device, which is a means for directly moving the blue electromagnet group, that is, the front electromagnet group and the back electromagnet group, include one central electromagnet facing the center in the width direction of the strip, and one central electromagnet facing the center in the width direction of the strip, and one central electromagnet facing the center in the width direction of the strip, and It is preferable to consist of two side electromagnets facing each other, and it should also be able to accommodate changes in the width of the strip (
Preferably, the central electromagnet is directly attached to the bogie rail frame, and the two side electromagnets are separately attached to a pair of electromagnetic carts that are movably assembled to the bogie rail frame in the width direction of the strip.

[Effect]

The strip passing position control device uses the magnetic attraction force of the cyan electromagnets against the strip to correct the C warpage occurring in the strip, and also prevents the generation of vibration in the strip by applying a restraining force to the strip without contact. However, if the strip passing between both types of magnet groups deviates from the neutral point of both types of magnet groups, this deviation will be automatically detected and the strip will be moved between both types of magnet groups by the magnetic attraction force of the electromagnet. It also serves to force the strip to return to its neutral point, thereby maintaining the strip passing position constant.

Both types of magnet groups of this strip passing position control device are installed with their neutral points located on the preset path line of the strip, and similarly both wiping nozzles also pass the intermediate position. Installed in line with the line.

Therefore, as long as the strip is traveling accurately on the set path line, both types of magnet groups are not particularly excited to correct the strip passing position.・Therefore, the fact that one electromagnet group of the strip passing position control device has become excited means that the strip passing position has shifted away from the pass line in the direction away from the excited one electromagnet group. It means.

Therefore, by moving both types of magnet groups in the thickness direction of the strip, or by moving the strip directly in the thickness direction,
A direction in which the excitation of one electromagnet group can be stopped,
In other words, by relatively moving this one electromagnet group in the direction toward the strip, the neutral point of both types of magnet groups and the actual passing position of the strip are made to coincide, thereby allowing continuous excitation of one electromagnet group. This prevents the electromagnet from burning out due to continuous excitation.

When moving both types of magnet groups, the strip passing position control device does not force the strip to change its passing position, so the strip can run in its natural state, and each electromagnet's There is no need to increase the capacity. On the other hand, when the strip passing position is moved by the strip drawer position control device, the warping deformation along the strip running line is corrected to some extent, so the strip passing position can be positioned on the pass line. In addition, if the setting itself of the strip passing position is incorrect, this setting error can be corrected.

In this way, since the strip passing position is made to coincide with the neutral point of both types of magnet groups, the strip passing position control device
It is now necessary to correct only the deviation from the pass line due to strip vibration, which reduces the burden on each electromagnet and prevents burnout, and also improves its ability to prevent strip vibration and C warping. can be fully and effectively demonstrated.

Both types of magnet groups of the strip passing position control device are attached to a bogie rail frame that is arranged to be movable in the thickness direction of the strip, so if one of the electromagnet groups continues to be energized for a certain period of time or more, the shift will occur. The source is activated to move the truck rail frame toward the other electromagnet group, ie, move one electromagnet group closer to the strip.

Due to this movement of the truck rail frame, the neutral point of both types of magnet groups coincides with the passing position of the IJ tube, so the excitation operation to correct the passing position of the strip of one electromagnet group is stopped.

The movement of the bogie rail frame by the shift source is performed by continuous excitation of one electromagnet group for a certain period of time or more, and excitation for vibration prevention or C warp correction is performed by short-term intermittent excitation. Therefore, in this case the truck rail frame is held immovable.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the configuration of a continuous hot-dip metal plating line in which the present invention is implemented, in which a strip S is placed near the bottom of a plating tank 25 filled with a plating solution K, which is molten metal. A hook is provided between the crawler 21 and a top roll (not shown) so as to run from the zinc roll 21 toward the top roll, and this zinc roll 2
A pass line PL is set by 1 and the top roll.

In the middle of the strip passage between the second zinc roll 21 and the top roll, there is a strip drawer position control device 14 disposed in order from the zinc roll 21 side near the pullout position from inside the plating solution. A wiping nozzle 22 and a strip passing position control device 1 are arranged. Both wiping nozzles 22 are installed in alignment with the pass line PL.

Both wiping nozzles 22 are connected via connecting pipes 23 to an immovably fixed header 24, to which the strip passing position control device 1 is attached.

The strip passage position control bag Wl includes a bogie rail frame 5 having a rectangular frame shape, a pair of front and back electromagnet groups 2.3,
The bogie rail frame 5 is composed of a shift source 11, a displacement meter 9, an excitation power source 12, and a control section 13.
It is mounted and assembled so as to be movable by wheels 8 on a bracket 7 fixed to the header 24 in a form extending in the thickness direction of the strip S, and this bogie rail frame 5
A shift source 11 composed of a pair of electric cylinders is assembled on one side of the shift source 11 . The dual-type magnet group 2.3 is composed of central electromagnets 2a and 3a facing the widthwise central portion of the strip S, and side electromagnets 2b and 3b facing the widthwise both ends of the strip S, As shown in FIG. 3, the central electromagnets 2a and 3a are directly attached to the center of the bogie rail frame 5, facing each other, and a displacement meter 9 is attached to the front center electromagnet 2a via a rod 10. It is being Central electromagnets 2a and 3a
Rails 6 are fixed to the inner surfaces of the frame parts of the bogie rail frame 5 to which the two electromagnetic bogies 5 are movably assembled on the rails 6 via wheels. One side electromagnet 2b and 3b are mounted facing each other on one electromagnet cart 4, and similarly, the other side electromagnet 2b and 3b are mounted facing each other on the other electromagnet cart 4. Similarly to the central electromagnet 2a, a displacement meter 9 is attached to the electromagnet 2b on the front side of the image.
It is attached by 0.

Therefore, when the width dimension of the strip S is changed, it is possible to easily accommodate the change in the width dimension of the strip S by moving the bichamber magnet cart 4.4. In addition, since the double-type magnet group 2.3 is configured by a combination of a central electromagnet and side electromagnets, the strip passing position control device 1 not only suppresses the vibration of the strip S but also corrects the C warp of the strip S. be able to.

The strip passing position control device 1 having the above-mentioned configuration is configured to measure this misalignment amount Δl by a displacement meter 9 when the passing position of the strip S deviates from the neutral point sp of the dual-type magnet group 2.3, which is the pass line PL. is detected and input as a detection signal to the control unit 13, which is a computer. The control unit 13 outputs an operation command signal according to the polarity and magnitude of the detection signal from the displacement meter 9 to the excitation power source 12 of the corresponding electromagnet,
This controls the excitation and degree of excitation and demagnetization of the corresponding electromagnet. The strip S shifted from the neutral point SP is moved by the magnetic attraction force of the electromagnet, and its passing position is moved to the neutral point S.
Place it in a suction position on p.

If the excitation of the front side electromagnet group 2 continues for a preset period of time or more, it is determined that the passing position of the strip S remains biased toward the back side electromagnet group 3 side, and the shift source 11 is activated, and the bogie rail frame 5 is moved in the direction in which the front electromagnet group 2 approaches the strip S until the excitation of the front electromagnet group 2 stops, that is, until the passing position of the strip S coincides with the neutral point SP.

The displacement meter 9 determines that the passing position of the strip S is the neutral point SP.
If it is detected that the shift source 12 is in agreement with the above, the control unit 13 stops the operation of the shift source 12 and moves the bogie rail frame 5.
hold immovably in that position.

The strip pull-out position control device 14 may be any device as long as it can change and control the pull-out position of the strip S from inside the plating solution in the thickness direction of the strip S, and as shown in FIG. A pair of support rolls 17 that are located inside the plating solution and sandwich the strip S are attached to the tip of a support arm 16 that moves horizontally forward and backward in the thickness direction of the strip S by a cylinder 15, or as shown in FIG. As shown in FIG.
A pressure roll is attached to the tip of the plating solution to press the strip S in one direction, and as shown in FIG. At the tip of the support arm 16 that moves forward and backward, a pair of flat regulation plates 20 are provided which face each other in parallel with the strip S sandwiched between them in the thickness direction.
It is possible to use a plating solution jet type in which the plating solution K is injected by a pump 19 between zero and the like.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the following effects.

Since the load on the electromagnet in the strip passing position control device is reduced, it is possible to prevent burnout caused by continuous excitation of the electromagnet over a long period of time, thereby ensuring stable and good control of the strip passing position control device over a long period of time. You can get the action.

Since the operation of each electromagnet of the strip passing position control device can be controlled within an appropriate range, the original operations of the strip passing position control device, such as strip vibration prevention and C warp correction, can be performed sufficiently under suitable conditions. In addition, the electromagnet can be used effectively, and the life of the electromagnet can be extended.

Trouble caused by electromagnet burnout can be prevented, so
The available production time can be expanded, and equipment safety costs for continuous hot-dip metal plating lines can be significantly reduced.

In claim 2, since the actual passing position of the strip is not forcibly changed, no wasted force is generated that acts in the direction of changing the passing position of the strip at the wiping point. The wiping nozzle can improve the ability to properly set and maintain the strip passing position, thereby making it possible to further improve the uniformity of the amount of plating solution deposited on the strip.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the arrangement of main components of continuous hot-dip metal plating line equipment in which the present invention is implemented. 2 and 3 show the structure of an embodiment of the strip passing position control device according to the present invention, with FIG. 2 being a front view and FIG. 3 being a plan view. Figures 4 and 5 show the configuration of the bogie rail frame portion to which the electromagnet is attached. Figure 4 is a longitudinal cross-sectional view of the central electromagnet portion, and Figure 5 is a longitudinal cross-sectional view of the side electromagnet portion. It is. 6 to 8 show the construction of different embodiments of the strip drawer position control device, FIG. 6 shows one constructed using a pair of support rolls, and FIG. 7 shows one constructed using a pair of support rolls. One is constructed using rolls, and FIG. 8 shows one constructed using a plating solution jet method. FIG. 9 is an explanatory diagram for explaining the magnetic attraction effect of both electromagnet groups on the strip. FIG. 10 is an explanatory diagram of the operating principle of continuous hot-dip metal plating using the gas wiping method. FIG. 11 is a perspective view showing the state of C-curvature of the strip in the continuous hot-dip metal plating shown in FIG. 10. Explanation of symbols I: Strip passing position control device, 2: Front side electromagnet group,
3; Backside electromagnet group, 2a, 3a; Central electromagnet, 2b, 3
b; Side electromagnet, 4; Electromagnetic cart, 5; Cart rail frame, 6; Rail, 7; Bracket, 8; Wheel, 9; Displacement meter, 10: Mounting with rond, 11; Shift source, 12; Excitation power source, 13; Control unit, 14; Strip drawer position control device, 15; Cylinder, 16; Support arm, 17; Support roll, 18; Press roll, 19; Pump, 20
:Regulation board, 21? Zinc roll, 22; Wiping nozzle, 23; Connection pipe, 24; Header, 25; Plating tank,
K: Plating solution, S: Strip, PL: Pass line, S
P: neutral point, Δl: amount of misalignment. Applicant: Kawasaki Steel Co., Ltd. 2Taku7tsu! = no Jyo M (Contents changed Gold 21---Shin 70-Rua color Ka 9 Bukkakuromono BL-Ichikoku/n1 Procedures (published by Hosei Seishin) ■. 2゜3゜4゜Indication of incident 1999 Patent Application No. t11855 Name of the invention Relationship between the method for controlling the strip passing position in continuous hot-dip metal plating and the case of the person correcting the strip passing position control device Patent applicant address 1-chome Kitahonmachi-dori, Chuo-ku, Kobe, Hyogo Prefecture No. 1 No. 28 Name (125) Kawasaki Steel Co., Ltd. Representative Hiroshi Yagibata Agent 164 ft (03) 382-6771
(Substitute) Drawings (all drawings) 6. Contents of amendment-f-10〃

Claims (4)

[Claims] (1) After the strip (S) has passed the wiping point, the actual passing position of the strip (S) is determined by the magnetic attraction force on the strip (S) of two groups of electromagnets arranged oppositely across the strip (S) from the thickness direction. The neutral point (s
p) In a continuous hot-dip metal plating line equipped with a strip passing position control device (1) that applies a magnetic attraction force to the strip (S) so that the strip (S) is Continuous hot-dip metal plating in which both electromagnet groups and the strip (S) are relatively moved in a direction in which the one electromagnet group approaches the strip (S) when the electromagnet is continuously excited for a certain period of time or more. Method for controlling sheet threading position. (2) The method for controlling the passing position of continuous hot-dip metal plating according to claim 1, wherein the relative movement of one electromagnet group in the direction toward the strip (S) is achieved by moving both electromagnet groups. (3) The relative movement of one electromagnet group in the direction approaching the strip (S) is controlled by the molten metal (K) of the strip (S).
) a strip pull-out position control device (14) that changes and controls the pull-out position from within the strip (S) in the thickness direction of the strip (S);
2. The method for controlling the passing position of continuous hot-dip metal plating according to claim 1, wherein the strip passing position is controlled by moving the strip (S) in the thickness direction. (4) At the position immediately after passing the wiping point, place a strip (S
) is arranged to be movable in the thickness direction of the carriage rail frame (5), and the strip (S) is mounted oppositely to the carriage rail frame (5) with the strip (S) sandwiched therebetween from the thickness direction, and the strip (S)
A front side electromagnet group (2) and a back side electromagnet group (3) that apply a magnetic attraction force to the bogie rail frame (
5) A shift source (11) for moving the strip (S) in the thickness direction of the strip (S).