JPS58100633A - Variable crown water cooled roll - Google Patents

Abstract

PURPOSE:To obtain a variable crown water cooled roll which is adjusted by giving the best crown to a steel strip optionally by forming a high presure liquid chamber which allows the free feedng and discharging of high pressure liquid inside of a metallic roll shell having a cooling water passage. CONSTITUTION:The pressure of supply liquid to a high pressure liquid chamber 30 is increased or decreased to adjust the swelling extent of a roll shell 3', giving a crown adequate for a steel strip to be treated. Then, cylinders 37 and 37 level a water cooled roll itself to perform more uniform cooling in the direction of plate width. In this case, a cooler 35 need not be provided unless the temperature of high pressure oil lowered by cooling water flowing inside of the shell 3' attains to high temperature. Further, the high pressure liquid may use water to perform cooling and adjustment of the crown. When this variable crown water cooled roll is used, the roll crown is adjusted to the best amount for the steel strip, and consequently the steel strip is cooled invariably uniformly in the plate width direction to realize stable operation and manufacture of a steel strip of superior quality.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to water-cooled rolls used as cooling rolls for cold-rolled steel strip for drawing in continuous annealing equipment, guide rolls in continuous casting machines, etc., and particularly relates to water-cooled rolls with variable crowns. The present invention relates to a water-cooled roll with a variable crown.

For continuous annealing of steel strips, the rapid cooling methods for steel strips include a water quenching method with a cooling rate of 1000~B, a water cooling roll method with a cooling rate of 75~B, and an air/water cooling method with a cooling rate of 200~B. , a gas jet system having a cooling rate of 20 to 20 b is known.

Among the rapid cooling methods mentioned above, the water-cooled roll method does not require post-treatment (pickling, etc.) after rapid cooling, has a faster cooling rate than the gas jet method, and has good aging properties with a short overaging treatment. It has the excellent advantage of being able to obtain cold-rolled steel strip.

FIG. 1 shows a system diagram of an example of a continuous annealing facility 1 using a water-cooled roll system and having water-cooled roll areas A and B.

The water-cooled rolls 2 used in the water-cooled roll areas A and B have different diameters, but both have spiral cooling water inside the roll shell 3, as shown in the longitudinal sectional front view in FIG. The cooling water passage 4 is supported by bearings 6, 6 provided outside the duct 5 so as to freely rotate.
, 2A, and is connected to a cooling water circulation system via a rotary joint 8.8.

In the continuous annealing equipment 1, as shown in FIG. 1, a steel strip 10 unwound from a tension reel 9 is cleaned in a cleaning section 11, and then passed through an inlet loop/*12 and then transferred from a heating furnace 13 to a soaking furnace 14. After being sent and heated to 700°C, it is heated to 400°C in water-cooled roll area A for 1
It is rapidly cooled at a rate of 00°C/S to 200°C/S. Next, the rapidly cooled steel 1O is subjected to over-aging treatment in the over-aging treatment zone 15, and is then taken out of the duct 5 through the water-cooled roll zone B, and then passed from the outlet root f15 to the tensile/J?
It passes through a mill 17 and is wound onto a tension reel 18.

In addition, the temperature at the time of placing the steel sheet IJ is measured by thermometers 19.20, 21, 22, and 23.24.

FIG. 3 is a diagram showing the temperature change of the steel IJ during the above-mentioned placement.

By the way, in water-cooled roll equipment, since the steel strip is cooled by direct contact between the water-cooled roll and the steel strip, there is a close relationship between the shape and crown of the roll and uniform cooling of the steel strip in the width direction.

For example, when using a convex crown roll, only the center of the steel strip is cooled, while the edges remain hot and uncooled. On the other hand, when a concave crown roll is used, only the edges are preferentially cooled and the center is not cooled.

In addition, the threadability of steel (steel steel)+Jdde becomes unstable.

Also, if you use a roll without a crown,
Since the contact condition with the rolls varies depending on the shape of the steel strip, it is difficult to cool it uniformly in the width direction.

However, in actual line operations, despite the differences in size, shape, and material of steel strip, the optimum roll crown is determined for the size of the steel strip that is most frequently threaded, and this single □-metal roll is always used. It is operated by Crown.

As a result, troubles such as poor shape, meandering, throttling in the furnace, and uneven quality were likely to occur in the steel IJ.

As a means to solve the above-mentioned problems, for example,
As seen in No. 10973, a method has been proposed in which the steel strip is cooled uniformly in the width direction by winding the steel strip around a water-cooled roll and cooling it with a gas body. Since the cooling is performed using a gas body, the cooling effect is small and the amount of gas used is large, resulting in high product costs.

In addition, the roll is made of elastic rubber roll, and the roll is made of steel.
A technique has also been proposed in which the roll and steel strip are always kept in complete contact for cooling, regardless of the shape and dimensions of the IJ Tsude.
If the temperature is not 0° C. or lower, the roll will be damaged, so it cannot be applied to a continuous annealing process.

In addition, depending on the size and shape of the steel strip, installing a water-cooled roll with an appropriate round each time requires a lot of time and effort to replace the water-cooled roll, and the downtime is long. This causes even bigger problems, such as a significant drop in operating rates.

The present invention is based on the above-mentioned viewpoints, and provides a variable crown water-cooled roll in which an optimal crown can be arbitrarily provided and adjusted. The present invention is characterized in that a high-pressure liquid chamber is formed in which high-pressure liquid can be freely supplied and discharged, and the crown can be changed freely by supplying and discharging liquid pressure to the high-pressure liquid chamber.

Next, the variable crown water-cooled roll of the present invention will be explained by way of embodiments with reference to the drawings.

FIG. 4 shows a partially cutaway longitudinal sectional front view of a first embodiment of the variable crown water-cooled roll of the present invention. The variable crown water-cooled roll 2' of this embodiment has a roll shell 3' provided with a spiral cooling water passage 4', and is supported on a fixed shaft 25 by bearings 26.degree. 26 so as to be freely rotatable.

The cooling water passage 4' is connected to rotary joints 27A and 27B (7111 hole 28) fixed to both ends of the roll shell 3'.
A and 28B are connected.

The rotary joints 27A and 27B are the guide holes 28A.

28B is a guide hole 29A formed in the fixed shaft 25.

29B, each of which is in constant communication with the joint,
One rotary joint 27A allows the cooling water supplied from the guide hole 29A to pass through the guide hole 28A to the cooling water passage 4', and further passes through the cooling water passage 4' to the roll shell 3.
’ to the other rotary joint 27B.
The cooling water is communicated with the guiding hole 29B via the guiding hole 28B, and the cooling water is returned to the cooling water cooler (not shown).

On the other hand, this variable crown water-cooled roll 2'lri o -
A high pressure liquid chamber 30 is formed inside the Luciel 3'.

The high pressure liquid chamber 30 includes a guide hole 31 bored in the fixed shaft 25.
One end of each of A and 31B is open, and the structure is such that high-pressure oil pumped from an oil tank 32 via a bonder 33 can be freely supplied and discharged.

In the hydraulic circuit 34 including the guide holes 31A and 31B, in addition to the oil tank 32 and the bonder 33, a cooler 35 and a variable flow rate adjustment valve 36 are provided to adjust the pressure in the high pressure liquid chamber 30. This allows the crown of the roll shell 3' to be adjusted.

The height of the fixed shaft 25 is freely adjustable using hydraulic cylinders 37.37, and bellows 39 are provided between the openings 5A, 5A of the duct 5 and the shaft support members 38.38.
．． 39 to prevent the atmosphere inside the duct 5 from leaking out, which is the same as in the conventional case.

Variable crown water-cooled roll 2 of the present invention configured as described above
According to ', the amount of expansion of the roll shell 3' can be adjusted by adjusting the supply liquid pressure into the high pressure liquid chamber 30, and a crown suitable for the steel strip to be processed can be provided. 37°37, by leveling the water-cooled roll itself, it becomes possible to achieve even more uniform cooling in the board width direction.

Note that the above-mentioned cooler 35 may be omitted when the temperature of the high-pressure oil is cooled by the cooling water flowing inside the roll shell 3' and does not reach a high temperature.

Alternatively, water may be used as the high-pressure liquid to perform cooling and crown adjustment.

Next, the cooling effect when steel strip is cooled using the roll of this first embodiment will be explained.

Plate thickness 0.4-1.6 IIB, plate width 600-1500m
A steel strip was cooled from 700° C. to 400° C. at a cooling rate of 100° C./sec in water-cooled roll area A shown in FIG. 1 using water-cooled rolls under the following conditions. Note that the line speed at this time was 80 mpm.

■Dimensions and number of rolls: 610mmφX1750smx5
■ Roll initial crown: 1.511 ■ Roll shell material 72 are copper, 3 are iron ■ Cooling water amount: 1 OT/) 1 ■ Oil pressure: t5Kg/cd Figure 5 shows cooling under the above conditions The temperature of the steel strip is shown when the vertical axis is the temperature of the steel strip, and the horizontal axis is the position of the steel strip in the width direction. 2. When adjusted within the OS range, B is the temperature when a conventional roll (crown 1.5 m) is used. Note that C is the temperature of the steel strip before cooling.

As can be seen from the drawing, when conventional rolls were used, the temperature difference in the width direction of the sheet was as much as 60 to 75 degrees Celsius.
The temperature difference when using the roll of the example with
It was possible to reduce it to a range of c.

The variable crown water-cooled roll 21 of the second embodiment shown in a longitudinal sectional front view in FIG. C and three non-circulating hydraulic circuits for each chamber 34A,
This embodiment differs from the first embodiment in that 34B and 34C are provided to make the crown of the roll shell 3I locally variable.

In this second embodiment, the shaft portions 2#A, 2''A supporting the roll shell 3 are rotated together with the roll shell 31, and the hydraulic circuits 34A, 34B.

The connection at 34C is performed by rotary joints 40A and 40B provided at the outer ends of shaft portions 2Nk and 2#A.

The rest of the structure is the same as that of the first embodiment, including the provision of a cooling water passage 4N.

Next, the cooling effect when steel strip is cooled using the roll of this second embodiment will be explained.

Plate thickness 0.4-1.6 m, plate width 600-1500 wIL
The CL steel strip was placed in the steel strip cold roll area A under the following conditions under water-cooled rolls, 650C and 400C.
It was cooled to C under cooling conditions of 100° C./see. Note that the line speed at this time was 80 mpm.

■Dimensions and number of rolls = 61o ■φX175011X5
■Roll initial crown: 2.0IIB ■Roll material = 2 rolls are copper, 3 rolls are iron ■Cooling water amount 2 rolls 10T/H ■Hydraulic pressure
: s s Kyf/lyA Figure 7 shows the temperature of the steel slit and Tsuke when cooling is carried out under the above conditions, and A' shows the temperature of the steel strip and Tsuke when cooling is carried out under the above conditions.
When adjusted in the range 2.0 IB, B' is the temperature when using a conventional roll (crown il 2.Om). Note that C' is the temperature of the steel strip before cooling.

As can be seen from the drawing, when conventional rolls were used, there was a temperature difference of about 100°C in the width direction of the sheet, but when the roll of this example was used, the temperature difference was less than 15°C. became.

The variable crown water-cooled roll 21' of the third embodiment shown in a longitudinal sectional front view in FIG.
There are two bearings 41° and 42 on the shaft part 2A, 2''A that supports the roll shell 3.
is provided, external pressure is applied with hydraulic cylinders 43 and 43, and bearing 4
1 and 41 are used as fulcrums for bending.

In this case, the supply of cooling water to the water-cooled roll 2N' is as follows:
Rotary joint 40'A.

40'B. In addition, in order to achieve further effects, the motors 45, 45 . Gear 46.46
It is also possible to provide a level adjuster 44.44 provided in the bearings 41, 41, and to adjust the tilting of the water-cooled roll 2' by this level adjuster 44.44.

Other structures include a cooling water passage 4' and a second
Same as the example.

Next, the cooling effect when steel strip is cooled using the roll of this third embodiment will be explained.

A steel strip with a thickness of 0.4 to 1.611B and a width of 610 to 1300 words was rolled in the water-cooled roll area B shown in Fig. 1.
From 300℃ to 100℃1 using a water-cooled roll under the following conditions.
It was cooled under a cooling condition of 50° C./see. Note that the line speed 9 at this time was 180 mpm.

■Dimensions and number of rolls: 800szφX175011X
5 pieces ■ Roll initial crown 20 ■ Roll material: Iron ■ Cooling water amount 2 rolls 10 /H ■
Bending pressure: @l roll 115 to 9/d 3rd
0-ru 35 Kf/d 50-ru 20 Kq/J Figure 9 shows the temperature of the steel strip when cooling is performed under the above conditions, A〃 is when the roll of this example is used, B〃 is This is the temperature when a conventional roll (crown amount 0.51B) is used. Furthermore, C1! is the temperature of the steel strip before cooling.

As can be seen from the drawing, when conventional rolls were used, the temperature difference in the sheet width direction was 30 to 40°C, whereas when the roll of this example was used, the temperature difference was about 5°C. No problems such as meandering or throttling of the steel strip occurred.

As explained above, if the variable crown water-cooled roll of the present invention is used in the water-cooled roll area of continuous annealing equipment, the roll crown can be adjusted to the optimum amount for the steel strip. The steel plate is always cooled uniformly in the width direction, eliminating the occurrence of meandering and drawing cracks in the steel plate, making it possible to produce steel plates with stable operation and excellent quality. Furthermore, when used as a guide roll in a continuous casting machine, it exhibits excellent functionality and brings about many industrial effects.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing an example of continuous annealing equipment, Fig. 2 is a vertical cross-sectional front view showing a conventional water-cooled roll, Fig. 3 is a diagram showing temperature changes of steel strip in continuous annealing equipment, and Fig. 4 is FIG. 5 is a longitudinal sectional front view showing the first embodiment of the variable crown water-cooled roll of the present invention with a part cut out. FIG. 5 is a diagram showing the results of cooling the steel strip according to the first embodiment. FIG. 7 is a diagram showing the results of steel strip cooling according to the second embodiment. FIG. 8 is a longitudinal front view showing the third embodiment. FIG. 9 is a longitudinal front view of the third embodiment. (steel steel) I
It is a figure showing the implementation result of J Tsubu. In the drawings, l... Continuous annealing equipment, 2... Water-cooled roll, 2',
2", 2"... variable crown water-cooled roll of this invention, 33', 31F, 3#'... roll shell, 4
, 4', 4#, 4''...Cooling water passage, 10...
Steel strip, 25...Fixed shaft, 27A, 27B
...Rotary joint, 30.30'...High pressure liquid chamber, 40A. 40B...Rotary joint, 41.42...Bearing, 43...Hydraulic cylinder, 44...Level adjustment machine Applicant Nippon Koukan Co., Ltd. Agent Keita Tsutsumi (1 other person)

Claims (1)

[Claims] A high-pressure liquid chamber in which high-pressure liquid can be freely supplied and discharged is formed inside a metal roll shell having a cooling water passage, and the crown can be freely changed by supplying and discharging liquid pressure to the high-pressure liquid chamber. Crown variable water cooling roll featuring.