JPH0543087Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention relates to a cooling device used in the primary cooling zone of continuous annealing equipment for cold-rolled steel sheets. The present invention relates to a roll cooling device that cools a roll by bringing it into contact with a roll cooled by a refrigerant such as water.

[Conventional technology]

Conventionally, methods for cooling cold-rolled steel sheets (strips) after heating include gas jet cooling, water cooling,
There are various methods such as air-water cooling method and roll cooling method, but the roll cooling method is the only method that has a fast cooling rate and does not wet the strip surface, and the equipment is simple. The law has become a focus of attention.

A primary cooling zone of a conventional continuous annealing facility for cold-rolled steel sheets equipped with such a roll cooling device is shown in FIGS. 6 and 7. In the figure, 20 is a preheating section, 21 is a heating zone.
Section), 22 is Soaking Section,
23 is a gas jet cooling zone.
Section), 24 is the roll cooling zone (Roll
25 is a reheating section, 26 is an overaging section, and 27 is a water cooling section.

In the primary cooling zone of this continuous annealing equipment for cold rolled steel sheets, a roll cooling zone 24 is arranged between a soaking zone 22 and a gas jet cooling zone 23, and a reheating zone 25 and an overaging zone 26. In the roll cooling zone 24, a coolant such as water is circulated inside the roll to cool the roll, and the strip after soaking is brought into contact with the cooled surface of the roll to be rapidly cooled. For example, as shown in the heat pattern in Figure 8, a strip that has been soaked at 700°C is first placed in the gas jet cooling zone 23.
It is cooled down to 600°C in the roll cooling zone 24, and further rapidly cooled down to 400°C in the roll cooling zone 24.

[Problem that the invention attempts to solve]

However, in conventional continuous annealing equipment, there was a problem in that as the operating time increased, the strip developed after the rolls were cooled, and the threadability of the strip deteriorated.

On the other hand, the inventor of the present invention has conducted extensive research into the mechanism by which the above-mentioned strip constriction occurs, and has discovered that the cause is as follows.

First, the relationship between the temperature distribution in the width direction of the strip after the roll was cooled and the wear rate distribution on the roll surface was investigated, and the results shown in FIGS. 9a and 9b and FIG. 10 were obtained. As shown in Figures 9a and b, the strip has a non-uniform temperature distribution in the width direction due to roll cooling, and the roll in this case has a temperature distribution on its surface as shown in Figure 10. Non-uniform wear rate distribution occurs. This non-uniform wear rate distribution is thought to be due to non-uniform shrinkage occurring in the strip during cooling, which caused the roll surface to wear unevenly, and the non-uniform temperature distribution of the strip top is due to the non-uniform shrinkage of the strip during cooling. This is thought to be due to uneven cooling between the strip and the strip due to uneven wear. It is conceivable that such uneven wear on the roll surface promotes unevenness in the strip temperature, resulting in the occurrence of constriction in the strip.

Therefore, we investigated the relationship between the temperature distribution after the roll was cooled, the flatness of the strip, and the narrowing of the strip, and the results shown in FIGS. 11a and 11b and 12a and 12b were obtained. As shown in each figure a, if the temperature distribution of the strip is uneven, defects in aperture and flatness occur as shown in each figure b. It can be seen that they are closely related.

From the above, it can be concluded that uneven wear on the roll surface causes uneven temperature distribution in the strip, which causes uneven temperature distribution and uneven tension distribution in the strip, resulting in strip drawing. Conceivable.

Conventionally, in order to prevent deterioration of strip threadability due to increased uneven wear on the roll surface, cooling rolls were replaced (reprocessing of the roll surface) every 2 to 4 months. This is the actual situation, and the problem is that the life of the cooling roll is short.

This invention was made under such circumstances, and aims to provide a roll cooling device that can suppress the occurrence of throttling in the strip while extending the cooling roll replacement cycle, that is, the roll life.

[Means for solving problems]

This invention is a roll cooling device that cools a strip using a cooling roll, and is provided with a roll shift mechanism that moves the roll cylinder in the axial direction.

[Effect]

In this invention, the axial position of the cooling roll is shifted, which makes it possible to even out the wear distribution on the roll surface caused by strip contraction, which lengthens the roll replacement cycle. , and the temperature distribution of the strip is prevented from becoming non-uniform.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a roll cooling device according to an embodiment of the present invention. In the figure, there is a roll barrel 2 inside the furnace shell 1.
A rotating shaft 3 is fixed to the roll cylinder 2, and the rotating shaft 3 is rotatably supported by a movable bearing box 4, and the rotating shaft 3 and the movable bearing box 4 are arranged in the axial direction. is fixed. In addition, the movable bearing box 4
A rotation drive device 5 for rotationally driving the rotation shaft 3 is disposed on a bracket fixed to the bracket. Furthermore, a cooling medium passage 6 for circulating a cooling medium such as cooling water is formed in communication with the roll cylinder 2 and the rotating shaft 3, and as described above, a cooling medium passage 6 is formed in communication with the roll cylinder 2 and the rotating shaft 3. A roll body 7 is configured.

The movable bearing box 4 is supported by a fixed housing 8 so as to be slidable in the axial direction of the roll cylinder 2, and the fixed housing 8 is suspended from a support frame 18 by a lifting worm jack 9. An elevating drive device 10 is connected to the worm jack 9, whereby the roll cylinder 2 is moved up and down together with the movable bearing box 4 and the fixed housing 8.

A female threaded member 11 is fixed to the movable bearing box 4, while a screw 12 into which the female threaded member 11 is screwed is supported by the fixed housing 8, and a shift drive motor 13 which rotates the screw 12. is fixed, and the roll shift mechanism 14 that shifts the roll body 7 in the axial direction of the roll cylinder 2 is configured as described above.

Next, the operation will be explained.

In this device, the cooling medium passage 6 of the rotating shaft 3
When a cooling medium such as water is supplied from the left end of the diagram,
This cooling medium flows through the internal cooling medium passage 6 of the left rotation shaft 3, the roll cylinder 2 and the right rotation shaft 3,
The liquid is discharged from the right end of the passage 6, thereby cooling the roll cylinder 2. When the rotational drive device 5 starts, the rotational force is transmitted to the rotating shaft 3 and the roll cylinder 2 rotates, whereby the strip in contact with the surface of the roll cylinder 2 is conveyed by the rotation of the roll cylinder 2. At the same time, it is cooled by the roll cylinder 2. Further, when the lifting drive device 10 operates, its driving force is transmitted to the lifting worm jack 9, and the roll cylinder 2 is moved up and down.
The contact length between the strip and the strip is adjusted to increase or decrease.

In this device, when the shift drive motor 13 operates, the screw 12 rotates, the movable bearing box 4 moves (shifts) in the axial direction within the fixed housing 8, and the shift of the movable bearing box 4 causes the roll cylinder to rotate. 2 also shifts. The shift amount of the roll cylinder 2 is changed by controlling the rotation speed of the shift drive motor 13.

Next, the present inventor investigated the roll surface wear rate and strip (plate) temperature distribution in order to confirm the effects when the roll was not shifted and when the roll was shifted. Figures 2 a to d show the plate temperature distribution and roll surface wear rate without roll shift;
Figures a to d show the plate temperature distribution and roll surface wear rate when a roll shift is present, and Figures 4 a to c show the plate temperature and roll surface wear rate when a roll shift different from the above is performed.

According to FIG. 2, when there is no roll shift, contraction of the strip on the cooling roll causes uneven wear on the roll surface as shown in b to d of the figure. Further, the temperature distribution in the width direction of the plate after cooling becomes a reverse pattern of the roll surface wear pattern, that is, a pattern in which the center temperature is high.

Also, according to Fig. 3, in the case of roll shift,
By shifting the roll, the wear area on the roll surface is expanded to a wide range of the roll surface (d in the same figure).
As a result, the maximum wear rate in the vicinity of ±400 mm from the center of the roll in the case of no roll shift disappears (b, c in the same figure). Accordingly, the temperature distribution of the plate after cooling also becomes smooth and has a mid-sole pattern (a in the same figure).

Furthermore, according to Fig. 4, by performing roll shifting, the wear condition of the roll surface itself is improved as shown in Fig. 3b (Fig. 4b), and each roll is used in a shifted state. By doing so (see figure c), the plate temperature distribution is further improved (see figure a).

In the apparatus of this embodiment as described above, since the roll is shifted in the axial direction, uneven wear on the surface of the cooling roll is suppressed and the wear distribution becomes smooth, resulting in reduction of the aperture caused by uneven cooling of the strip. It is possible to control the occurrence of such problems.

In addition, with this device, since uneven wear of the rolls can be suppressed, the distance until repolishing of the rolls can be extended, that is, the roll replacement cycle can be extended, making it possible to increase production capacity and reduce replacement costs.

Furthermore, this device is effective in suppressing changes in roll surface properties other than wear distribution. For example, if a roll whose surface is thermally sprayed with carbide, oxide, etc. and polished with a grinder is used as a cooling roll,
Iron etc. tend to adhere to the roll surface, but this device is effective against such problems.

Further, FIG. 5 shows another embodiment of the present invention. In this embodiment, only the roll cylinder 2 is shifted while the rotating shaft 19 remains fixed in the axial direction. The rotating shaft 19 has a length extending outward from the left and right sides of the furnace shell 1, and its left and right ends are rotatably supported by a bearing box 15, and the bearing box 15 is suspended by a worm jack 9 so as to be able to rise and fall freely. ing. Also, the rotating shaft 3
A roll cylinder 2 is attached to the center of the rotary shaft 19 so as to be slidable in the axial direction by a spline connection using a spline 16.
A built-in cylinder 17 for moving the roll cylinder 2 in the axial direction is provided, and a piston rod 17a of the cylinder 17 is connected to the roll cylinder 2. Note that 17b is a hydraulic pressure supply passage.

In this device, the shift guide is spline 16.
The shift amount is determined by the built-in cylinder 1.
This is done by controlling the amount of hydraulic oil to 7.

Although the above embodiments have been explained using continuous annealing equipment as an example, the present invention can of course be applied to any type of roll cooling equipment that cools a strip using a cooling roll. .

[Effect of idea]

As described above, according to the present invention, in a roll cooling device that cools a strip using a cooling roll,
Since the roll cylinder is moved in the axial direction,
Uneven wear on the surface of the roll cylinder can be reduced, and as a result, the occurrence of strip thinning can be suppressed, and production capacity can be increased and costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a roll cooling device according to an embodiment of the present invention, and FIGS. 2 to 4 are diagrams for comparing the effects without roll shift and with roll shift. Figure a shows the plate temperature distribution without roll shift, Figures 2 b to d both show the wear rate distribution on the roll surface without roll shift, Figure 3 a shows the plate temperature distribution with roll shift. Figures 3b to 3d are diagrams showing the plate temperature distribution, and Figures 3b to 3d are diagrams showing the wear rate distribution on the roll surface with roll shift.
Figure 4a is a diagram showing the plate temperature distribution with another roll shift, Figures 4b and c are both diagrams showing the wear rate distribution of the roll surface with another roll shift, and Figure 5 is a diagram showing the wear rate distribution of the roll surface with another roll shift. Block diagram of another embodiment of the present invention, No. 6
Fig. 7 and Fig. 7 are respectively an overall configuration diagram and a configuration diagram of main parts of continuous annealing equipment, Fig. 8 is a diagram showing an example of a heat pattern in continuous annealing equipment, and Figs. Figure 10 is a diagram showing the wear rate distribution on the roll surface, Figures 11a and b are diagrams each showing the temperature distribution in the width direction of the strip after cooling the roll, and the strip at that time. Diagram showing flatness, Figure 12 a, b
2A and 2B are diagrams showing the temperature distribution in the width direction of other strips after roll cooling, respectively, and diagrams showing the flatness of the strip at that time. In the figure, 2 is a roll cylinder, and 14 is a roll shift mechanism.

Claims (1)

[Scope of utility model registration request] A roll cooling device configured to rotate a roll cylinder cooled by a refrigerant and cool the belt-shaped object by bringing the belt-shaped object into contact with the surface of the roll cylinder,
A roll cooling device comprising a roll shift mechanism for moving the roll cylinder in an axial direction.