JPH07109555A - Method for exchanging hot dip coating bath - Google Patents

Abstract

PURPOSE:To provide a means capable of safely and rapidly exchanging a hot dip coating bath. CONSTITUTION:A hot dip coating bath at an operation position is lowered with its intrabath equipment and moved to a standby position by a truck, another fresh bath provided with intrabath equipment is moved to the operation position by the truck and raised to a specified height. Consequently, the baths are exchanged in a shorter time, the working rate of a hot dip coating line is improved, dross is sufficiently removed, and the product quality is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for replacing a molten metal plating bath in a continuous molten metal plating facility.

[0002]

2. Description of the Related Art In continuous hot dip coating, a steel strip is continuously immersed in a molten plating metal bath, and the surface of the steel strip pulled up from the bath is subjected to gas wiping to adjust the coating amount to a predetermined level. It is well known that hot dip galvanizing is a typical method of applying a predetermined plating to the surface of a steel strip.

By the way, in the production of hot-dip galvanized steel sheet, the components of the plating bath may be slightly different depending on the type of production. For example, in galvannealing,
The amount of Al added is smaller than that of hot-dip galvanizing (zinc iron plate), and even with the same hot-dip galvanizing, the normal spangle product and the minimized spangle product may be manufactured with different amounts of Pb added. In such a case, by using a plurality of plating baths having completely different components, it is possible to minimize the influence on the product due to the change of the plating bath components at the manufacturing stage.

Further, in recent years, alloyed hot-dip galvanized steel sheets have been widely used for automobile exterior steel sheets, and the required quality thereof has been increasing. Is a problem. As a countermeasure against this, a plurality of plating baths having the same composition are alternately used, and while one plating bath is being used for manufacturing, the other plating bath is cleaned and then replaced and used. The impact can be reduced.

Conventionally, the following method has been known as a method for exchanging a molten metal plating bath in a continuous molten metal plating facility. For example, JP-A-1-177344
In the gazette, when replacing the plating bath, a method is proposed in which the plating bath is moved up and down and moved horizontally while leaving the in-bath equipment such as a sink roll and the steel strip in the operating position. That is, this method lowers the plating bath to a predetermined position, moves it to a standby position, then moves a new plating bath to an operating position, raises it to a predetermined height position, and replaces the plating bath. It is something to do.

[0006] In Japanese Utility Model Laid-Open No. 2-149754, a plurality of plating baths are mounted on a turntable so as to be able to move up and down while leaving in-bath equipment such as sink rolls, and each turntable is swung. An exchange device has been proposed in which plating baths are alternately used.

[0007]

However, the conventional plating bath replacement method and plating bath replacement device described above are
There are drawbacks described below. (1) In either method, the equipment in the bath such as a sink roll and the plating bath are separated, and only the plating bath is moved and replaced. Therefore, when moving the plating bath from the operating position, On the other hand, molten metal adhering to the equipment in the bath may drip, and the molten metal may adhere to the plating bath, moving carriage, etc., resulting in damage to the equipment or hindering smooth movement. (2) Since the equipment in the bath must be replaced at the operating position, it is not preferable in terms of safety as well as it takes a lot of time and labor to replace the equipment in the bath. (3) In order to avoid thermal shock, the equipment in the bath must be heated (preheated) to the temperature of the molten metal to some extent and put into the plating bath. Therefore, when the equipment in the bath is transported to the operating position, the assembly work must be performed in a high temperature state, which is extremely dangerous work. (4) A large number of large jacks are required for the lifting mechanism of the plating bath, resulting in high equipment costs. (5) It is not possible to secure a sufficient space for dross removing work in the production of alloyed hot-dip galvanized steel sheets for automobile exteriors.

The present invention has been made to solve the above-mentioned drawbacks of the prior art, and proposes a plating bath replacement method capable of efficiently, safely and promptly performing the replacement work of the hot dipping bath. It is what

[0009]

According to the present invention, in a continuous hot-dip metal plating facility, when a plurality of plating baths having the same plating bath component are replaced, the plating bath at the operating position is equipped with an in-bath device. To a position where it can be moved horizontally, then move the plating bath horizontally to the standby place, and then move the plating bath equipped with new equipment in the bath waiting at another standby place horizontally to the operating position. At this position, the plating bath is elevated to a predetermined height for replacement, and when a plurality of plating baths having different plating bath components are replaced, the plating bath at the operating position is equipped with an in-bath device. In that state, it is lowered to a position where it can be moved horizontally, after which the plating bath is moved horizontally to the standby position, and after removing the bathing equipment at that position, move the bathing equipment to another standby location. It is installed in a plating bath having different components, and the plating bath equipped with the equipment in the bath is horizontally moved to the operating position, and the plating bath is raised to a predetermined height position at that position for replacement. To do.

[0010]

Function The in-bath device is detachably attached to the plating bath via the hanger. The plating bath is mounted on a bath trolley, and a bath tub elevating jack for raising and lowering the bath tub is installed at an operating position. At the standby position, a plurality of stand-by trucks each having a plating bath are mounted, and each stand-by truck is provided with a plating bath having the same component or a plating bath having different components.

When exchanging the plating bath, the steel strip is cut and separated from the bathing equipment, and then the bathtub is lowered with the bathtub lifting jack while the bathing equipment is installed, and the bath cart is moved horizontally. And mount it on the waiting cart. Therefore, when the plating bath is moved from the operating position, the molten metal does not drop and adhere to the moving carriage, rail, or the like, and there is no movement trouble. The plating bath is transported to the standby location by the standby cart, where the device hanger for bathing is attached and detached. During this time, move the plating bath equipped with new bath equipment in another standby location to the operating position, and use the jacks for raising and lowering the bath to raise the plating bath to the predetermined height position for each bath truck for replacement. To complete.

On the other hand, in the case of replacing a plating bath having a different composition, after removing the hot water from the equipment hanger in the bath removed at the standby place, the plating bath of a different component waiting the hanger at another standby place. Install on. If the bath equipment needs to be replaced, of course, it should be replaced with a new bath equipment. When the attachment of the in-bath device hanger is completed, the plating bath is moved to the operating position, and the plating bath is lifted to a predetermined height position for each bath truck by the bath lifting jack to complete the exchange.

According to the present invention, since the work for attaching and detaching the hanger during bathing can be performed in a space much wider than the operating position, the crane can be easily handled and the work can be performed easily and quickly. In addition, since the in-bath device preheating equipment and the in-bath device placement table can be arranged close to each other, the assembling work of the in-bath device can be performed safely and quickly.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a conceptual diagram schematically showing an example of a plating bath replacement method of the present invention, and FIG. 2 is an enlarged view of an example of plating bath replacement equipment in the same plating bath replacement method. FIG. 1 is a plan view, 1 is a plating bath, 2 is a bathing device, 3 is a hanger, 4 is a bathtub truck, 5 is a bathtub lifting jack, 6-1 is a standby truck running rail, and 6-2 is a bathtub traveling. Rail, 6-3 is a rail for mounting on the bathtub,
Reference numeral 7 is a waiting cart, and 8 is a gas wiping device.

FIG. 1 shows an arrangement in which two plating bath standby positions are provided for one operating position, and two plating baths can be made to stand by at each standby position when there is no operation. ing. The arrows in the figure indicate the movement of the bathtub.

That is, when the A pot in the operating position is to be replaced with the B pot located in the waiting place B, the A pot is moved to the waiting place A to attach / detach bath equipment.
Then, while the A pot is moved to the standby location A, the B pot is moved to the operating position and exchanged. When replacing the B pot in the operating position with the A pot located in the standby place A, the B pot is moved to the original standby place B while the B pot is located in the standby place A, contrary to the above. Move the existing A pot to the operating position again and replace it.

Next, the plating bath exchanging equipment shown in FIG. 2 will be described. The plating bath 1 is mounted on a bath truck 4 and is supported by a jack 5 for raising and lowering a bath installed at an operating position. . The in-bath device 2 includes a stabilizing roll 2-1, a collecting roll 2-2, and a sink roll 2-3, and is detachably attached to the plating bath 1 via the hanger 3.

A standby carriage running rail 6-1 connects the standby places A and B, and the standby carriage 7 travels on this rail. In addition, the rail 6-
1 and the operating position, at the same level as the rail 6-3 for laying on the bathtub stand installed on the upper surface of the truck 7 for standby, a rail 6-3 for running the standby truck 6-1, and a rail 6-for running the bath truck 6 at a right angle
2 is laid, on which the bath truck 4 runs.

Next, the procedure for replacing the plating bath will be described below. (1) When the components of the two plating baths are the same First, after the line is stopped, a steel strip (not shown) is cut on the plating bath 1 of the A pot to be separated from the in-bath device 2. When the steel strip is detached from the bath equipment 2, the plating bath 1 is lowered by the bath lift jack 5 while the bath equipment 2 is attached by the hanger 3, and then placed on the bath carriage rail 6-2. Place it. Subsequently, the bath tub 4 is moved to the standby trolley traveling rail 6-1 side and transferred onto the standby trolley 7 that is pre-positioned on the end side of the bath tub traveling rail 6-2. To do. When the bath trolley 4 is transferred onto the standby trolley 7,
The stand-by cart 7 is moved to the stand-by place A, and the bath equipment hanger 3 is attached and detached at this place. On the other hand, while the A pot moves to the standby location A, the standby carriage 7 equipped with the B pot equipped with the new bathing device 2 is moved and stopped at the end of the bath carriage running rail 6-2. In this state, the bathtub truck 4 is transferred onto the truck traveling rail 6-2, and the bathtub truck 4 carrying the B pot is moved to the operating position. Thereafter, a steel strip is passed through the in-bath device 2 of the B pot to start the operation. During the operation of the B pot, the dross in the bath of the A pot is collected, cleaned, and put on standby next time.

(2) When Components of Two Plating Baths are Different In this case, after moving the A pot to the standby place A by the same procedure as above, the in-bath device 2 and the hanger 3 removed
After removing the hot water, the equipment 2 and the hanger 3 in the bath are transported to the standby place B by a crane and attached to the plating bath 1 having different components. At this time, if the bath equipment 2 is damaged and needs to be replaced, of course, a new bath equipment is used. After that, the plating bath 1 at the standby place B is moved to the operation position by the same procedure as above, and the operation is started.

[0021]

As described above, the present invention is a method of exchanging the bath equipment with the bath equipment attached to the plating bath, and the attachment / detachment work of the bath equipment is provided at a position away from the operating position. Since it can be done in the standby place, a work place wider than the operating position can be secured, and the attachment / detachment work and dross removal work can be simplified and speeded up, and the equipment for preheating equipment in the bath and the equipment table for bath equipment Since and can be placed close to each other, the work of assembling the devices in the bath can be performed safely and quickly.

Further, not only when the components of the plating bath are the same, but also when the baths having different components can be exchanged by the same equipment, it is extremely advantageous for the production of various kinds of hot-dipped steel sheets, and the equipment Since the structure is also simple, the facility cost is relatively low, and since the molten metal does not fall outside the tank and damages the equipment, the repair cost is not high.

Therefore, according to the method of the present invention, the operating rate of the hot-dip galvanizing line and the quality of the hot-dip galvanized steel sheet can be improved, and the manufacturing cost can be reduced, resulting in a great industrial effect.

[Brief description of drawings]

FIG. 1 is a conceptual diagram schematically showing an example of a plating bath replacement method of the present invention.

FIG. 2 is a vertical cross-sectional view taken along line A-A of FIG. 2 showing an enlarged example of plating bath replacement equipment in the same plating bath replacement method.

[Explanation of symbols]

 1 Plating bath 2 Equipment in bath 3 Hanger 4 Bath dolly 5 Jack for bath tub lifting 6-1 Rail for running trolley for standby 6-2 Rail for traveling tub trolley 6-3 Rail for mounting on bath tub 7 Standing trolley 8 Gas wiping apparatus

Claims (2)

[Claims] 1. A method for exchanging a molten metal plating bath in a continuous molten metal plating facility, wherein when exchanging a plurality of plating baths having the same plating bath component, the plating bath at the operating position is replaced with an in-bath device. The equipment is lowered to a position where it can be moved horizontally, and then the plating bath is moved horizontally to the standby location, and then the plating bath of the new equipment in bath that is waiting at another standby location is brought to the operating position. A method for exchanging a hot-dip galvanizing bath, which comprises horizontally moving and elevating the galvanizing bath to a predetermined height position at the position. 2. A method for exchanging a molten metal plating bath in a continuous molten metal plating facility, wherein when exchanging a plurality of plating baths having different plating bath components, the plating bath at an operating position is equipped with an in-bath device. In that state, it is lowered to a position where it can be moved horizontally, after which the plating bath is moved horizontally to the standby location, the bathing equipment is removed at that position, and then the bathing equipment is placed on standby at another standby location. Replacing a hot dip bath which is installed in a bath with different components, horizontally moves the bath equipped with equipment in the bath to the operating position, and raises the bath to a predetermined height at the position. Method.