JPH0651262U - Continuous hot dip plating equipment - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a continuous hot dip plating apparatus that can easily remove foreign matters floating on the hot dip metal bath surface without interrupting the plating operation and melting the snout. . [Structure] A continuous hot dip plating apparatus in which a snout provided with an atmosphere gas introduction pipe is provided on the steel strip exit side of the annealing furnace and a gap is provided from the hot dip metal bath surface.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a continuous hot dip plating apparatus for plating a running steel strip with a molten corrosion resistant metal such as zinc, tin, lead-tin, aluminum or an alloy thereof.

[0002]

[Prior art and its problems]

 The continuous hot-dip galvanizing equipment consists of a pre-oxidizing furnace for surface-activating the running steel strip, a reduction annealing furnace for reducing and softening in a reducing gas atmosphere, a duct-shaped snout for cooling in a reducing atmosphere and hot dip plating. It consists of a metal tank, a gas wiping nozzle above this, and a temperature control furnace. Such continuous hot dip coating equipment has the advantage that various types of plated steel sheets with different coating weights from thin plating to thick plating can be easily manufactured by changing the running speed of steel strip compared to the dopping method. It is commonly used.

However, the continuous hot-dip galvanizing apparatus as shown in, for example, Japanese Patent Laid-Open Nos. 63-47355 and 63-118057 discloses foreign matter in the annealing furnace carried by a steel strip and hot-dip galvanizing. There was a problem that the dross formed in the bath floated on the surface of the molten metal bath in the snout and adhered to the strip, significantly impairing the plating appearance. In addition, the steam generated from the hot-dip metal bath surface inside the snout adheres to and accumulates on the inner wall of the snout and the annealing furnace, and falls onto the steel strip and hot-dip metal bath surface, resulting in appearance defects called blemishes and non-plating. There was also a problem that occurs.

Due to these problems, a continuous hot-dip galvanizing apparatus having a foreign matter removing technique has been developed, as disclosed in Japanese Patent Publication No. 63-49743. This plating equipment is a "technology that removes foreign substances from the gap by creating a gap between the tip of the snout and the surface of the hot-dip metal bath while supplying an inert gas into the snout." It provides a snout device that removes foreign substances easily by moving a snout that is connected to the outlet side of the furnace and has its tip immersed in a hot dip metal bath up and down. Such an apparatus has an advantage that foreign matters floating on the surface of the melt-plated metal bath in the snout can be easily removed, as compared with the above-described conventional continuous hot-dip plating apparatus.

However, when it becomes necessary to remove the foreign matter in the snout, the plating operation is temporarily interrupted, the snout is moved upward, and a gap is created between the tip of the snout and the hot-dip metal bath surface, Since this is a method of removing foreign matter from the snout through the gap, there is a problem that the operation must be stopped when a large amount of foreign matter is generated despite the plating operation under the same conditions. Moreover, if the deposits that adhered to the inner wall of the snout were neglected during long-term operation, the appearance flaws such as the flaws on the plated steel sheet were unavoidable. Furthermore, since the snout is always immersed in the hot-dip metal bath for use, there is a problem of melting damage.

[0006]

[Means for Solving the Problems]

 Due to such problems, the present invention provides a continuous hot-dip galvanizing apparatus which can always easily remove foreign matters floating on the hot-dip metal bath surface without interrupting the plating operation and melting the snout. However, the gist is a continuous hot dip coating apparatus in which a snout having an atmosphere gas introduction pipe is connected to the steel strip exit side of the annealing furnace with a gap from the hot dip metal bath surface.

Hereinafter, the present invention will be described in detail. The figure shows an embodiment of the present invention. Reference numeral 1 denotes an annealing furnace, which shows a part of the outlet side. 2 is a steel strip. A turndown roll 3 is an in-furnace roll provided near the exit of the annealing furnace 1. That is, the steel strip 2 is provided so as to run around the turndown roll 3 while being softened in the annealing furnace 1. Reference numeral 4 is a snout, which is connected to the steel strip outlet side of the annealing furnace 1. The snout 4 is a duct-shaped pipe provided with an atmosphere gas introduction pipe 5 for supplying an inert gas such as nitrogen or argon gas or another gas, and is arbitrarily selected from the bath surface of the hot-dip metal 7 in the hot-dip metal tank 6. The gaps (preferably 5 to 20 mm) are provided for connection.

That is, the snout 4 is provided so as to guide the steel strip 2 running in the annealing furnace 1 into the bath of the hot-dip metal 7 while protecting it with the atmospheric gas. The atmospheric gas introduced into the snout 4 is ejected from the lower outlet. Reference numeral 8 is a sink roll, which is a roll for turning the steel strip 2 passing through the hot dip metal bath. Reference numeral 9 denotes a wiping gas nozzle, which wipes and adjusts an excess amount of the welded molten plated metal adhering to the steel strip 2 passing through the bath of the molten plated metal 7 and rising to a predetermined basis weight.

According to the continuous hot-dip galvanizing apparatus of the present invention configured as described above, the traveling steel strip 2 is softened in the annealing furnace 1 and then filled with an arbitrary atmospheric gas and discharged from the lower outlet. After passing through the jetting snout 4 and passing through the hot dip metal bath 6, the product is wiped to a predetermined basis weight to produce a plated steel sheet. During the plating operation, the atmospheric gas ejected from the snout 4 into the narrow gap between the hot-dip metal 7 and the hot-dip metal 7 prevents oxidation of the hot-metal bath near the area where the steel strip 2 invades while maintaining a beautiful appearance. To manufacture. Further, in the present invention, the snout 4 is connected to the outlet side of the annealing furnace 1 with a gap provided on the bath surface of the hot-dip metal 7 to form a hot-dip galvanizing apparatus. Foreign particles floating in the molten metal bath can be easily removed, and the snout 4 is not melted, and it can be operated continuously for a long time.

[0010]

[Effect of device]

 As described above, according to the present invention, it is possible to easily remove foreign matters floating on the hot-dip metal bath surface without interrupting the plating operation and only melting the snout, thus enabling long-term continuous operation. It has become possible.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

[Explanation of symbols]

 1 Annealing furnace 2 Steel strip 3 Turndown roll 4 Snout 5 Atmosphere gas introduction pipe 6 Hot dip metal bath 7 Hot dip metal 8 Sink roll 9 Gas wiping nozzle

Claims (1)

[Scope of utility model registration request] 1. A continuous hot dip coating apparatus, wherein a snout provided with an atmospheric gas introduction pipe is connected to the steel strip exit side of the annealing furnace with a gap provided from the hot dip metal bath surface.