JPH0120226B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous molten metal plating apparatus, and more particularly to a continuous molten metal plating apparatus for steel strips, in which a steel strip pass line in a molten metal plating bath can be easily changed.

In recent years, plating thickness control in continuous molten metal plating equipment such as zinc and aluminum on steel strips has mainly been carried out using a gas throttling method. If the shape of the steel strip is not flat, the plating thickness of the steel strip will be different on the front and back sides and in the width direction, resulting in non-uniformity.

For this reason, in the case of a continuous molten metal plating apparatus using a gas throttling method, a guide roll or a magnetic type steel strip vibration prevention device is arranged for the steel strip to prevent vibration and correct the shape of the steel strip.

The former method involves placing a guide roll near the bath surface where the steel strip rises above the molten metal plating bath (hereinafter referred to as plating bath), and using the guide roll to press the steel strip to one side. In order to increase the effect of the guide roll, it is generally arranged so that the pass line of the steel strip from the plating roll to the top roll is bent. That is, in the case of this method, as shown in FIG. 1, the steel strip 1 is preheated and reduced in the pretreatment zone 2, as in the conventional general continuous molten metal plating apparatus, and then passed through the nose roll 3 and the snout 4. The plating bath 5 enters the plating bath 5, and then the direction is changed by a plating roll 7 provided below the plating machine 6, and the plating thickness is further controlled by a gas throttle device 8 at the rising position from the plating bath 5. Then, the top roll 9 and the cooling device 10 are reached. Two guide rolls 11 are arranged below the bath surface at the rising part of the steel strip 1 from the bath surface, and the steel strip 1 is sandwiched between these guide rolls 11. The steel strip surface is pressed toward the snout side to prevent vibrations and correct the shape of the steel strip 1.

However, the effect of the guide roll 11 becomes greater as the contact area with the steel strip 1 and the resistance become larger. For this reason, the conventional guide roll 11
The steel strip 1 is arranged closer to the snout 4 than the plating roll 7, so that the steel strip 1 is bent at the guide roll 11, and rises perpendicularly from the guide roll 11 to the top roll 9.

Therefore, since the path line of the steel strip leading to the top roll 9 has been determined by the arrangement of the guide rolls, the surface treatment device 12 performs alloying treatment, mini-spangle treatment, etc. on the steel strip 1 after plating. It is arranged and positioned along this pass line, and its movement direction is also limited to the width direction of the steel strip 1, so that it is set accurately with respect to the pass line of the steel strip when in use. Ta.

Conventionally, the arrangement of the guide rolls 11 is to use two rolls to sandwich the steel strip 1 as described above, a method in which the steel strip 1 is pressed by one roll, or a method in which the axes of the two rolls are shifted. Although methods such as bending the steel strip 1 into an S-shape are also used, in order to increase the effect of the arrangement of the guide rolls 11, the steel strip 1 is placed between the plating roll 7 and the top roll 9. It was arranged so that the pass line was bent towards the snout 4 side.

However, since guide rolls are always used by being immersed in high-temperature molten metal, heat-resistant and corrosion-resistant steel has been used as the material; Conventional guide rolls have not been able to function as guide rolls for a long period of time due to formation of an uneven alloy layer or wear of the bearings. Furthermore, in order to maintain its functionality at a certain level, maintenance management is not easy, and furthermore, there is a need for improvement in terms of the impact on product quality and manufacturing costs.

On the other hand, the magnetic type steel strip vibration prevention device 13, as shown in FIG. An outward tension is applied in a non-contact manner, thereby preventing vibrations and correcting the shape of the steel strip 1.

This device can prevent vibrations and modify the shape of the steel strip 1 in a non-contact manner, and is sufficiently effective without being placed in molten metal, making maintenance management easy and stable. However, due to the non-contact between the steel strip 1 and the steel strip 1, there were cases where there was a limit to its effectiveness. For example, if the shape of the raw steel strip becomes extremely bad, or if the shape of the steel strip becomes extremely bad due to uneven heating conditions in the pretreatment zone immediately after the start of operation of the continuous molten metal plating device, the steel strip vibration prevention device 13 Gas throttle device 8 when used alone
It was not possible to prevent vibrations or correct the shape of the steel strip 1 during passage, and there were cases where the steel strip 1 collided with the gas throttling device 8.

For this reason, vibration prevention and shape correction of the steel strip 1 have conventionally been carried out by using a guide roll 11 and a steel strip vibration prevention device 13 in combination, as shown in FIG.

However, as mentioned above, guide rolls have various problems, so when the shape of the steel strip 1 is good, we switch to using only the magnetic type steel strip vibration prevention device 13, and when the shape is bad, we switch to using both together. Switching is a good idea for maintenance management and product quality.

By the way, when switching to the use of only the vibration prevention device 13 for the steel strip, the path line between the plating roll 7 and the top roll 9 of the steel strip 1 was bent toward the snout 4 by the guide roll 11.
The steel strip 1 moves in a straight line (dotted line in FIG. 1) and comes into contact with the gas throttling device 8, the surface treatment device 12, etc. Therefore, when switching to the use of only the steel strip vibration prevention device 13, it is necessary to simultaneously move the gas throttle device 8, surface treatment device 12, etc. along the pass line. However, since it is extremely difficult to move these devices at the same time, it has not been put to practical use so far.

In the present invention, the guide roll 11 and the vibration prevention device 1 for the steel strip are moved by moving the plating roll 7 instead of moving the gas squeezing device 8, the surface treatment device 12, etc.
This makes it possible to switch between using the steel strip vibration prevention device 13 in combination with the steel strip vibration prevention device 13 and using the steel strip vibration prevention device 13 alone.

That is, the present invention makes the rise position of the steel strip 1 from the plating bath 5 constant by changing the pass line of the steel strip 1 in the plating bath 5 depending on whether or not the guide roll 11 is used. The present invention provides a continuous molten metal plating device that can perform continuous molten metal plating.

In the present invention, a magnetic steel strip vibration prevention device is disposed at a position on both end sides of a pass line of the steel strip that rises approximately vertically from the plating roll of a plating machine in which the plating roll of the steel strip is provided below. In a continuous molten metal plating apparatus, a fulcrum arm having a fulcrum that serves as a center point during rotation on one side of the plating roll at the top of the plating machine is raised and lowered by a lifting device to the opposite side, and The plating machine was rotated around the fulcrum of the plating arm, and the plating roll was made movable by providing lifting arms for moving the plating roll in an arc shape.

The present invention will be explained in detail below.

Changing the pass line of the steel strip 1 in the present invention The plating roll 7 is moved in an arc shape, and as shown in FIG. Make sure it is an extension of the pass line. Since it is difficult to separate and move only the plating roll 7 during the movement, the plating machine 6 is rotated with the plating roll 7 attached to the plating machine 6. For this purpose, it is difficult to set the center of rotation of the plating machine 6 inside the plating bath 5, so it is set outside the plating bath 5.

Therefore, in the present invention, when moving the center of the plating roll 7 from O ₁ to O ₂ in FIG. 2, the center point P of the circle such that these O ₁ and O ₂ are on the same circumference is plated set outside the bath 5, and this center point P
If the plating machine 6 is rotated by a predetermined angle with
Move from S ₁ (solid line) to a straight line S ₂ (dotted line). Also, the center point P may be used for reverse movement.

Note that due to the movement of the plating roll 7, the pass line of the steel strip 1 from the nose roll 3 to the plating roll 7 moves slightly as shown by the dotted line in FIG.
However, this movement of the pass line may be carried out within a range that does not hinder the passage of the steel strip 1 through the snout 4.
In fact, there are several changes in the pass line within Snout 4.
Since there is no problem up to about mm, the position of the center point P can be set so that the distance (rotation radius) between _O1 and P is in the range of about 1200 to 2000 mm.

FIG. 3 shows an embodiment of a plating machine 6 suitable for moving the plating roll 7 as described above. In this plating machine 6, the arm 14 is attached to two back arms 14 fixed to the plating machine 6.
A fulcrum arm 15, which is perpendicular to the fulcrum, is fixed to each. A fulcrum 16 is provided below each tip of the fulcrum arm 15.
The plating machine 6 can be rotated around 6.

On the other hand, a lifting arm 18 is fixed to the two front arms 17 fixed to the plating machine 6 at right angles to the arms, and a lifting device 1 is attached to the lower side of each tip.
9 is placed. This lifting device 19 may be fixed to the lifting arm 18 or may be arranged separately.

An arm fixing seat 21 for fixing the plating machine 6 to an arm stand 20 (FIG. 4) is provided at the tip of each of the rear arm 14 and the front arm 17.

Next, the plating machine 6 is rotated according to FIG.
Let us explain the process of changing the pass line of the steel strip 1 in the plating bath 5 from S ₁ to S ₂ . Note that S ₁ is better than S _2.
If you want to change it to , just do the following steps in reverse.

Now, when rotating the plating machine 6, first remove the fixing bolts 22 that fix the back side arm 14 and the lifting arm 18 to the arm stand 20 via the arm fixing seat 21, and then attach the guide roll 11 to the steel strip. 1, the lifting arm 18 is pushed up by the lifting device 19. At this time, the plating machine 6 is rotated about the fulcrum 16, and the plating roll 7 is moved in an arc shape.

When the lifting arm 18 reaches a predetermined position, the lifting device 19 stops pushing up the lifting arm 18, and the rear arm 14 and the front arm 1
7 and the arm stand 20, and then fix this block 23 and each arm again with the fixing bolts 22.
to fix it to the arm stand 20.

As described above, since the plating machine 6 in the apparatus of the present invention has a structure that allows it to rotate around the fulcrum 16, the plating roll 7 can be moved in an arc shape, and therefore the plating machine 6 can rotate in the plating bath 5. The pass line of the steel strip 1 can be easily changed.

As mentioned above, in the plating machine using the apparatus of the present invention, the fulcrum, the part for moving the plating machine, and the part for fixing the plating machine are separated, so each part has only one function. This is convenient in terms of design and allows each function to be strongly demonstrated. Therefore, the plating machine can be firmly fixed to the arm stand, and the plating machine itself will not become a source of vibration of the steel strip during operation.

Furthermore, the plating machine using the device of the present invention can achieve its purpose by simply equipping a conventional plating machine with a fulcrum arm, a lifting arm, a lifting device, and a block, and each member except the block can be plated. It is structurally simple, as it only needs to have enough rigidity and torque to temporarily support and rotate the machine.
Can be made small.

Furthermore, in the case of a plating machine using the apparatus of the present invention, it is also possible to replace the guide roll in preparation for switching to use in combination with a guide roll during plating.

As described above, according to the present invention, the pass line of the steel strip in the plating bath can be easily changed, so that vibration prevention and shape correction of the steel strip can be performed using only the magnetic type steel strip vibration prevention device. Also, the surface treatment device placed on the plating bath can be used as is. Moreover, if only the vibration prevention device is used, maintenance management becomes easier and product quality can be expected to improve.

[Brief explanation of drawings]

Fig. 1 is a side view of a conventional continuous molten metal plating device, Fig. 2 is an explanatory diagram for explaining the method of moving the plating roll, Fig. 3 is a plan view of the plating machine of the present invention, and Fig. 4 FIG. 2 is a side view of the plating machine of the present invention when it is rotated and fixed. 1... Steel strip, 2... Pretreatment band, 3... Nose roll,
4...Snout, 5...Plating bath, 6...Plating machine, 7
... Plating roll, 8... Gas squeezing device, 9... Top roll, 10... Cooling device, 11... Guide roll, 12... Surface treatment device, 13... Steel strip vibration prevention device, 14... Back side arm, 15... Support arm , 16... Fulcrum, 17... Front side arm, 18... Lifting arm, 19... Lifting device, 20... Arm stand,
21...Arm fixing seat, 22...fixing bolt, 23...
Block.

Claims (1)

[Claims] 1 Continuous melting in which magnetic steel strip vibration prevention devices are placed at positions on both end sides of the steel strip pass line that rises approximately vertically from the plating roll of the plating machine in which the steel strip plating roll is installed below. In the metal plating apparatus, a fulcrum arm having a fulcrum that serves as a center point during rotation on one side of the plating roll at the top of the plating machine is raised and lowered by a lifting device to the opposite side, and the fulcrum arm is raised and lowered by a lifting device on the opposite side. A continuous molten metal plating device for steel strips, characterized in that the plating machine is rotated around a fulcrum, and lift arms are provided for moving the plating roll in an arc shape.