JPS642663B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a cooling tower in a continuous high speed melt plating facility.

[Conventional technology]

Figures 1 and 2 show conventional continuous melt plating equipment.
To explain with a diagram, 3 is a plating tank, 8a, 8
b, 8c, 8d, 8e, 8f are hot-dip galvanized steel plates 7
a cooling duct for cooling the molten plated metal, 9a,
9b, 9c, 9d, and 9e are deflector rolls 10a, 10b, 10c, and 10d that guide the hot-dip galvanized steel sheet 7 while changing its passing direction; presser rolls attached to the deflector rolls; Mist spray tank for cooling to temperature. Note that each of the deflector rolls 9a to 9e is free, and the traveling of the hot-dipped steel plate 7 is performed by rotationally driving a bridle roll (not shown) installed downstream of the mist spray tank 12. . Further, the presser rolls 10a to 10d are separated from the body surfaces of the deflector rolls 9a to 9e during normal operation, and do not come into contact with the hot-dip galvanized steel plate 7. As will be described later, these presser rolls 10a to 10d are placed close to the surfaces of the deflector rolls 9a to 9e when replacing or repairing the plating machine.
It has the role of holding down and pulling up the hot-dip galvanized steel plate 7 upwards by electric drive.

A steel plate is introduced into a plating tank 3 from an annealing furnace 1 via a turndown roll 2, plated via a sink roll 4, and rises onto the plating tank 3 through a finishing roll 5. The molten galvanized steel sheet 7 that has risen above the tank has the thickness of the molten galvanized metal adhered to it adjusted by the blow-wipe spray nozzle 6, is initially cooled by the first cooling duct 8a, and is then leveled by the deflector roll 9a. Then, in the apparatus shown in FIG. 1, the deflector roll 9
b, 9c, pass through each cooling duct 8b, 8c, 8d, and then change direction with the deflector roll 11 to the mist spray tank 12.
In the apparatus shown in FIG. 2, each cooling duct 8b, 8c, 8d, 8e, while changing direction by deflector rolls 9b, 9c, 9d, 9e.
8f, the mist is further changed direction by a deflector roll 11, and introduced into a mist spray tank 12.

The hot-dip galvanized steel sheet 7 cooled to a predetermined temperature in the mist spray tank 12 is then sent to the next process, where it is subjected to predetermined treatments such as shape modification and chemical conversion treatment.

[Problem that the invention seeks to solve]

In the above-mentioned conventional continuous hot-dip plating equipment, meandering occurs in the hot-dip-plated steel plate 7, making it difficult to maintain a smooth threading condition, and in extreme cases, sheet breakage accidents may occur due to meandering, and Since metal powder and dust are attached to the surface of the deflector roll, this will be pressed against the soft plating metal on the surface of the hot-dipped steel sheet, causing hit and push-in scratches on the hot-dipped steel sheet, etc. This made it difficult for Metsuki operations.

Furthermore, the work of replacing the plating machine such as the sink roll 4, finishing roll 5, nozzle 6, etc. (for example, replacing the nozzle 6)
(replaced every 5 to 10 days), melt plating should be done on the part that rises from the plating tank 3 and reaches the cooling duct 8a so as not to obstruct the movement of the crane for the replacement work. A deflector roll 11 descends from the steel plate 7 and the final stage cooling duct (8d in FIG. 1, 8f in FIG. 2).
It is necessary to perform a punching operation to remove the hot-dip galvanized steel plate 7 in the area that extends to . For this purpose, the rising part from the plating tank 3 and the cooling duct 8 at the final stage are
The hot-dipped steel plate 7 is cut at the falling part from d and 8f, and the presser rolls 10a to 1 are cut.
0d to each of the deflector rolls 9a to 9e to sandwich the hot-dipped steel plate 7, and press the presser roll 10.
By the electric drive of a to 10d, the molten plated steel plate 7
By rolling up the molten-plated steel plate 7, the cut hanging portion of the molten-plated steel plate 7 is removed upward from the traveling space of the crane.
It is stored on floors (not shown) from the fourth floor to the fourth floor.
However, the cutting process is extremely complicated and takes a long time.

The present invention attempts to solve the above problems.

[Means and actions for solving problems]

The cooling tower structure in the high speed continuous melt plating equipment according to the present invention includes: a first cooling duct 8a for cooling the hot melt plating steel plate 7 rising from the plating tank 3 and moving upward; a first deflector roll 9a for horizontally deflecting the passed molten plated steel plate 7; a second cooling duct 8b for cooling the molten plated steel plate 7 moving in the horizontal direction after passing through the first deflector roll 9a; A second deflector roll 9b that deflects the molten-plated steel plate 7 that has passed through the second cooling duct 8b downward, and a third deflector roll that cools the molten-plated steel plate 7 that moves downward through the second deflector roll 9b. It has a cooling duct 8c, and a looper for forming a loop of the hot-dip plating steel plate between the first deflector roll 9a and the second deflector roll 9b, and the looper is always used (during the hot-plating operation). is the first deflector roll 9a and the second deflector roll 9a.
Each deflector roll serves as a drive roll located apart from the deflector roll 9b, and which rolls down the molten plated steel plate onto the surface of each deflector roll when forming a loop and winds up the molten plated steel plate hanging from each deflector roll by rotational movement. Presser rolls 10a, 10b attached to the presser rolls 10a, 10b, and a steel plate path between the first deflector roll 9a and the second deflector roll 9b for storing the hot-dipped plated steel plate rolled up by the rotation of the presser rolls 10a, 10b as a loop. It is characterized by consisting of a pair of loop guide rolls 13a and 13b provided at the lower part of the line.

The present invention will be explained with reference to FIG. 3. After the hot-dip galvanized steel plate 7 passed through the plating tank 3 and was hot-plated, the coating weight of the plating metal was adjusted by the blow-wiping spray nozzle 6. 1 cooling duct 8
a, and then horizontally deflected through the first deflector roll 9a to undergo secondary cooling in the second cooling duct 8b. After passing through the second cooling duct 8b, the second deflector roll 8
b, and further passes through the third cooling duct 8c, thereby receiving tertiary cooling. Third
through the cooling duct 8c to a predetermined temperature (approximately 150
The molten-plated steel plate 7, which has cooled down to 180° C., is again deflected horizontally by the deflector roll 11 and introduced into the mist spray tank 12.

In the above normal sheet passing state, the presser rolls 10a and 10b are connected to the first deflector roll 9.
a, away from the second deflector roll 9b; In addition, the looper guide rolls 13a, 13
b is not involved in the traveling of the hot-dipped steel plate 7, and the hot-dipped steel plate 7 moves straight from the first deflector roll 9a to the second deflector roll 9b through the second cooling duct 8b.

In the above equipment, a plating machine, for example, nozzle 6
When replacing the hot-dipped steel plate 7, first
The sheet threading is stopped, and the hot-dipped plated steel plate 7 is cut at the rising part from the plating tank 3 and the falling part from the third cooling duct 8c to the deflector roll 11, and the presser roll 10a is
The presser roll 10b is also attached to the body surface of the second deflector roll 9a.
The hot-dip galvanized steel plate 7 is rolled down at each portion by pressing it against the surface of the body. Next, by rotating the presser roll 10a, the lower end (cut end) of the molten-plated steel plate hanging down from the first deflector roll 9a is raised to a predetermined height (a height that does not interfere with the movement of the building crane). ), and the extra length of the rolled up hot-dipped plated steel plate 7 is stored as a loop in the loop guide rolls 13a and 13b. Similarly, by rotating the other presser roll 10b, the lower end (cut end) of the molten-plated steel plate 7 hanging down from the second deflector roll 9b does not interfere with the movement of the building crane. The extra length of the rolled-up molten-plated steel plate 7 is rolled up until it rises to a high height, and the extra length of the rolled-up molten-plated steel plate 7 is rolled up into loop-forming guide rolls 13a, 13.
Store as a loop in b.

The figure shows an example in which the loop guide rolls 13a and 13b are installed between the first deflector roll 9a and the inlet of the second cooling duct 8b.
Instead, the second cooling duct 8b outlet and the second
It goes without saying that it may be installed between the deflector roll 9b and the deflector roll 9b, and the operations and effects in that case are the same as in the above case.

Since the cooling tower structure of the present invention is simplified to a two-deflector system consisting of the first deflector roll 9a and the second deflector roll 9b, the meandering of the molten-plated steel sheet 7 in the cooling tower can be avoided even under high-speed sheet threading operation. There are almost no. Furthermore, since there are fewer opportunities for contact between the hot-dip galvanized steel sheet 7 and the deflector roll, the occurrence of hit and push-in flaws on the plating metal surface of the hot-dip galvanized steel sheet is reduced. Its incidence is approximately that in conventional equipment.
75% or less.

In addition, when replacing the plating machine, etc., the presser roll is
Winding up by electric drive of 0a and 10b and storage in the looper can be done easily and in a short time. The time required for cutting out the board is reduced to about 30% compared to conventional methods.

In addition, it was generally said that the hot-dip galvanized steel plate 7 must be cooled to about 100 to 130° C. when it passes through the cooling tower and is introduced into the mist spray tank 12. In the cooling tower structure of the present invention, the number of cooling ducts is smaller than in conventional equipment, so the mist spray tank 1
The temperature of the molten plated steel sheet just before it is introduced into the cooling duct (depending on the cooling conditions in the cooling duct) is approximately 150 to 180.
℃, which is a little high. However, through detailed experiments conducted by the inventors, we have found that it is not necessary to cool the hot-dip galvanized steel sheet to 100-130°C, and even if it is slightly higher, at approximately 150-180°C, there is no problem in terms of quality or processing process. has been confirmed.

〔Effect of the invention〕

According to the present invention, stable high-speed operation can be performed without causing meandering of the hot-dip plated steel sheet in a continuous hot-dip plating line, and the surface quality of the hot-dip plated steel sheet is improved by reducing hit and push-in scratches.

Furthermore, the work of blanking out sheets, which is carried out when replacing the plating machine, etc., can be done easily and in a short time, so that the line stop time can be shortened and the operating rate can be improved.

In addition, because the structure is significantly simplified, the equipment cost, including the building, is significantly reduced to about 60% of conventional equipment.

[Brief explanation of drawings]

Figures 1 and 2 are diagrams schematically showing conventional equipment;
FIG. 3 is a diagram schematically showing an embodiment of the present invention. 3: Plating tank, 7: Hot-dip galvanizing steel plate, 8a-8
e: Cooling duct, 9a-9e: Deflector roll, 10a-10d: Presser roll, 13a, 13
b: Guide roll for loop formation, 12: Mist spray tank.

Claims (1)

[Claims] 1. A first cooling duct for cooling the hot-dip galvanized steel sheet that rises from the plating tank and moves upward, a method for horizontally diverting the hot-dip galvanized steel sheet that has passed through the first cooling duct. a first deflector roll for cooling the hot-dip galvanized steel sheet that moves horizontally through the first deflector roll;
a cooling duct, a second deflector roll that deflects the molten-plated steel sheet that has passed through the second cooling duct vertically downward, and a third deflector roll that cools the molten-plated steel sheet that has passed through the second deflector roll and moves downward. a cooling duct, and a looper for forming a loop of hot-dipped steel plate between the first deflector roll and the second deflector roll, and the looper is normally connected to the first deflector roll and the second deflector roll. Attached to each deflector roll as a drive roll located away from the deflector roll, which rolls down the molten-plated steel plate onto the surface of each deflector roll during loop formation and winds up the molten-plated steel plate hanging down from each deflector roll through rotational movement. A presser roll is provided at the lower part of the steel plate pass line between the first deflector roll and the second deflector roll for storing the molten-plated steel plate rolled up by the rotation of the presser roll as a loop. A structure of a cooling tower in continuous high-speed melt plating equipment, characterized by comprising a pair of loop guide rolls.