JPS6214122Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a roll crown amount adjusting device for a roll for stripping in a heat treatment facility for heating, soaking, cooling, etc.

In strip heat treatment equipment, such as a heating furnace or a cooling furnace, strip threading rolls in the furnace are usually provided with crowns to prevent meandering. However, meandering of the strip in such threading rolls depends on the material, shape, and size of the strip, the line speed, the temperature difference in the strip width direction, and other line conditions, so it is extremely difficult to determine the appropriate crown amount from the beginning of line operation. Although it is possible to improve the determination of such crown amount to some extent by a long-term line investigation of the above-mentioned conditions, a decrease in line speed during that time inevitably leads to production loss and deterioration of product quality. That is, in order to prevent meandering until the appropriate crown amount is determined, the meandering is corrected by a steering device, but generally, this steering device does not allow a wide range of meandering correction, so meandering correction cannot be performed over the entire line, and therefore a measure to prevent meandering by reducing the line speed is required. However, even if the crown amount is determined as described above, it is not possible to accurately respond to constantly changing conditions such as material shape and size. For example, if the crown amount is relatively large, thin plates, soft plates, wide plates, etc., squeezing (stretching and wrinkling of the strip due to plastic deformation) will occur.
This causes a decrease in quality or a defective product. For this reason, even if a crown is provided, it is necessary to keep the crown amount to the smallest amount among the amounts determined based on the above-mentioned various conditions, and therefore the improvement of the meandering of the strip has to be sacrificed to some extent.

In addition, in contrast to the above-described initial crown, there is a problem in that a thermal crown is generated in a passing roll of a heating furnace, a cooling furnace, or the like. That is, in a cooling furnace, the temperature of the strip is higher than the temperature of the atmosphere inside the furnace, so the surface of the threading roll that the strip comes into contact with expands thermally, while other parts of the strip expand thermally.
In other words, the end of the roll body where the strip does not touch does not undergo much thermal expansion, and as a result, a large convex thermal crown is formed in the longitudinal direction of the roll body.As a result, the effect of preventing meandering of the strip increases, but the disadvantage is that the strip Apertures are more likely to occur.

On the other hand, in a heating furnace, the temperature of the strip is lower than the temperature of the atmosphere inside the furnace, so the surface of the threading roll that the strip contacts is cooled;
The ends of the roll body, which the strip does not touch, are not cooled as much and this creates a concave thermal crown in the center of the roll, resulting in the problem of strip meandering.

The present invention has been devised in view of the above points, and its purpose is to provide a device that can arbitrarily adjust the roll crown amount of a threading roll depending on the line and other conditions.

Embodiments of the present invention will be described below with reference to the drawings.

Figures 1 to 3 show an embodiment of the present invention, in which 1 is a furnace wall of heat treatment equipment (e.g., heating furnace, cooling furnace, etc.), 2 is an upper threading roll in the furnace, and 3 is a strip. be. In the present invention, heat shielding plates 4, 4 are arranged on both sides in the width direction of the roll body 21 of the passing roll 2, that is, above or below the roll body end portions a, a, so as to be able to rise and fall with respect to the roll. When the present invention is applied to the upper passing roll 2, the heat shield plates 4, 4 are arranged above the roll.

The heat shield plate 4 is configured to surround at least approximately half the circumference of the roll over a predetermined width from each end of the roll body 21, and in this embodiment is configured to have a generally semicircular cross section. There is. This heat shield plate 4 surrounds the roll body ends a, a which are not in contact with the strip 3, and therefore its length in the roll width direction is determined by taking into account the minimum width of the strip, etc. Ru. Further, in this embodiment, a reflector plate 41 made of nickel alloy or the like is provided inside the heat shield plate 4.
Further, a heat insulating plate 42 made of an asbestos board or the like is provided on the outside of the reflecting plate 41.

In this embodiment, the heat shielding plates 4, 4 as described above can be raised and lowered using the center side of the roll body 21 in the width direction as a fulcrum. That is, rotating shafts 5, 5 are rotatably disposed on the upper part of the threading roll 2 and intersect with the width direction of the roll body 21 at the center thereof. Heat shield plate 4, 4
is fixed. One end of each of the rotating shafts 5, 5 protrudes outside the furnace, and is rotationally driven by a motor 7 provided outside the furnace via a speed reducer 8. The heat shield plates 4, 4 can be raised and lowered from a horizontal state (0°) to a vertically (90°) state by rotation of the rotating shafts 5, 5. Note that the heat shielding plate 4,
4 is preferably disposed in a horizontal state, that is, in an overturned state so as to surround the roll body end portions a, a, so that its inner surface is as close as possible to the roll surface.

Further, the heat shielding plate 4 may be raised up and down using the roll body end portions a, a side as a fulcrum, and in this case, the rotating shafts 5, 5 are disposed at the roll body end portions a, a side, respectively. will be established.

Note that the above embodiments relate to the case where the device of the present invention is applied to the upper threading roll, but when applied to the lower threading roll, the strip is wound around the lower surface of the threading roll, so it is not heated. It is necessary to provide the shielding plates 4, 4 below the threading roll 2, and in this case, a shielding plate is used that can enclose at least the lower half of the circumference from each end of the roll over a predetermined width. Furthermore, the device of the present invention can be applied to any sheet passing rolls in cooling furnaces, heating furnaces, soaking furnaces, etc.

Taking as an example the effect of the device of the present invention as described above and applying it to a passing roll in a cooling furnace. The surface of the threading roll thermally expands, whereas the other parts, that is, the roll body ends a, which are not in contact with the strip, dissipate heat to the furnace wall and furnace atmosphere.
It does not undergo much thermal expansion, which results in a large thermal crown in the center of the roll body 21. Therefore, in this case, the heat shielding plates 4, 4 are turned over to the roll side, and the roll body ends a, a are surrounded to prevent heat dissipation. That is, the heat shield plate 4 is connected to the roll body 21.
When tilted in the direction, most of the heat dissipation from the upper part of the roll body end a to the furnace wall and furnace atmosphere is blocked by the heat shield plate 4. In particular, in this embodiment, the heat shielding plate 4 has a reflecting plate 41 on its inner surface and a heat insulating plate 42 on its outer surface.
The temperature of the reflecting plate 41 increases in response to heat radiation from the roll, and the temperature becomes approximately equal to the surface temperature of the roll, thereby preventing heat radiation from the surface of the roll body end a. Further, because of the heat insulating plate 42 on the back side of the reflector plate 41, heat dissipation from this to the furnace wall etc. can be suppressed to a minimum. However, by preventing heat dissipation from the roll body end a in this way, the roll body end a can also obtain a relatively large amount of thermal expansion. The difference in the amount of crown can be minimized.

Further, in the apparatus of the present invention, the tilting angle of the heat shielding plate 4 can be arbitrarily selected within the range of 0° to 90° with respect to the roll body 21, thereby making it possible to obtain an arbitrary crown amount. Figures 4 and 5 show the roll profile and roll crown amount when the crown amount is adjusted by applying the device of the present invention to a passing roll in a slow cooling furnace (furnace temperature: 300°C, stripping temperature: 600°C). In Figure 3, at normal temperature, the opening degree of the heat shield plate is 0°, the same is 10°, the same is 40°,
also shows the case of 90°. According to these, when the opening degree of the heat shield plate 4 is 90°, that is, when the device of the present invention is not actually used, an extremely large thermal crown occurs, whereas when the opening degree of the heat shield plate 4 is made small. In other words, it is shown that by tilting the roll body 21, the amount of thermal crown at the center and both ends of the roll body 21 becomes balanced, and it can be seen that the amount of roll crown can be adjusted arbitrarily. .

Furthermore, the above description has been made of the case where the device of the present invention is applied to a cooling furnace or a slow cooling furnace, but as mentioned above, the device of the present invention can also be applied to sheet rolling rolls in heating furnaces, soaking furnaces, etc. In this case, the heat shield plates 4, 4 function to block heat radiation from the atmosphere in the furnace to the end of the roll body, and therefore, in this case, it is not necessarily necessary to provide a reflecting plate.

According to the device of the present invention described above, the heat transfer between the roll body end and the furnace atmosphere is blocked within an appropriate range by the heat shielding plate, and thereby the amount of thermal crown at the roll body end can be set arbitrarily. Therefore, by adjusting the amount of crown appropriately according to the size and material of the strip, it is possible to pass the strip smoothly without meandering or squeezing. There are advantages.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a plan view, and FIG. 2 is a plan view of the embodiment of the present invention.
3 is a view taken along the line in FIG. 2; FIG. 3 is a view taken along the line in FIG. 4 and 5 show the roll profile and roll crown amount obtained by roll crown adjustment according to an embodiment of the present invention. In the figure, 2 is a threading roll, 3 is a heat shield plate,
21 each indicates a roll body.

Claims (1)

[Scope of utility model registration request] Above or below both sides of the passing roll in the strip heat treatment equipment, a heat shielding plate that can surround at least half of the roll over a predetermined width from each end of the roll body can be raised and lowered relative to the roll. A roll crown amount adjustment device is provided.