JPH0679728B2 - Roll cooling device for rolling mill - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a cooling device for cooling work rolls of a rolling mill, and is particularly suitable for cooling work rolls of a plate rolling mill for producing plate materials and strip steels. Cooling device.

[Background of the Invention]

The rolling roll of the rolling mill is constantly heated during rolling due to processing heat due to plastic deformation from the rolled material and frictional heat generated between the rolled material and the roll. In particular, when hot rolling, the temperature of the rolled material is as high as about 1200 ° C,
The rolling roll becomes very hot. The heat generated by the slip between the rolling roll and the rolled material further heats the rolling roll.

The heating of the rolling roll first starts at the surface of the roll that comes into contact with the rolling material, and proceeds from this surface in the radial direction toward the center of the roll. Also, regarding the longitudinal direction of the roll,
Heating proceeds from the axial center of the roll toward both ends. Therefore, in the longitudinal direction of the roll, the temperature at the central portion is the highest, and the temperature gradually decreases toward both ends. Therefore, the diameter of the rolling roll is
The central part becomes larger than both ends due to thermal expansion. The difference in diameter due to this thermal expansion is 0.1 to 0.4 mm in the case of hot rolling.
Reach a degree.

If the diameter of the roll is large in the central part and small in both ends, the thickness of the rolled material at the center of the width becomes thinner,
There is a problem that rolling accuracy becomes poor. Further, when the temperature of the rolling roll becomes high, seizure between the rolling material and the roll occurs, and the surface quality of the product deteriorates.

For this reason, the rolls of the rolling mill need to be constantly cooled during rolling. Therefore, conventionally, cooling water is sprayed onto the surface of the roll from a position separated from the roll by using a spray nozzle to cool the roll. The average heat transfer coefficient from the roll surface is 3000 kcal / m ² hr ℃, and the cooling capacity is limited. In order to improve this, various attempts have been made such as increasing the amount of cooling water or increasing the pressure of cooling water, but there is a limit to this and the rolls cannot be cooled sufficiently.

Therefore, a method for significantly improving the above-mentioned insufficient cooling has been proposed in Japanese Patent Laid-Open No. 47502/1983. In this method according to the prior art, a cooling water guide plate formed of a flexible member having a shape along the outer circumference of a work roll is arranged at a constant interval with respect to the roll, and the cooling water guide and The average heat transfer coefficient is improved by forcibly supplying cooling water to the gap between the rolls and pressing both ends of this cooling water guide plate against the work rolls by springs. However, such a prior art also has the following drawbacks.

The rolling roll is worn by rolling the rolled material, and the diameter of the rolling roll is periodically changed by 0.1 to 0.5 mm. And
In the cooling device described in JP-A-58-47502,
The cooling water guide plate has a flexible member, and both ends of the cooling water guide plate are pressed against the work roll by springs, and the fluid resistance and the spring of the cooling water supplied between the cooling water guide plate and the roll surface. The cooling water guide plate is deformed by the pressing force of the roller so that the cooling water guide plate can follow the change in the diameter of the roll. However, in the method of deforming the cooling water guide plate using this fluid pressure and spring force, it is difficult to increase the amount of deformation because a large fluid pressure cannot be obtained. I could only follow the changes. On the other hand, the amount of roll modification finally reaches about 10% of the roll diameter, and the deformation amount of the cooling water guide plate cannot follow the change of the roll diameter, so that the roll cannot be cooled sufficiently. Further, if the amount of cooling water decreases for some reason, the fluid pressure decreases, the cooling water guide plate and the roll come into contact with each other, and there is a drawback that an accident such as seizure between the cooling water guide plate and the roll is likely to occur. Furthermore, in order to make the gap between the cooling water guide plate and the roll uniform in the circumferential direction,
It was difficult to make the deformation of the cooling water guide plate have the same curvature, that is, a circular shape.

[Object of the Invention]

The present invention, even when the roll diameter is significantly changed,
An object of the present invention is to provide a roll cooling device for a rolling mill, which can keep a proper gap between the cooling water guide plate and the roll and can sufficiently cool the roll.

[Outline of Invention]

In the present invention to achieve the above object, a cooling water guide plate having a curved surface along the circumferential direction of the roll, which is provided close to the roll of the rolling mill, and cooling formed by the cooling water guide plate and the roll. A water supply member that supplies cooling water to the water flow path, a drain member that drains the cooling water supplied by the water supply member, a support member that supports the cooling water guide plate in the central portion, and this cooling water guide plate In a roll cooling device of a rolling mill having a bending deformation member that adjusts the upper and lower end positions to change the curvature of the cooling water guide plate with respect to the diameter of the roll, the curvature of the cooling water guide plate is set to the curvature of the roll. The cooling water guide plate is formed so that the thickness of the cooling water guide plate gradually increases from the vertical end toward the center so that the radius of curvature of the cooling guide plate becomes substantially constant when the diameter is changed. Is a thing

Example of Invention

A preferred embodiment of a roll cooling device for a rolling mill according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view of an embodiment of a roll cooling device according to the present invention.

Reference numerals 10 and 12 shown in FIG. 1 denote a work roll and a lower work roll for rolling down the rolled material 14, respectively. The cooling device 16 is
Provided in contact with the upper work roll 10 and also the lower work roll
12 also has a similar cooling device as described later. The cooling pad 18 of the cooling device 16 has a cooling water guide plate 20 integrally formed with a thin end portion and a thick central portion on the surface facing the upper work roll 10. The cooling water guide plate 20 extends along the axis of the upper work roll 10 and is curved along the circumferential direction of the upper work roll 10.
And a cooling water passage 22 is formed between them. Cooling pad 18
Is a plurality of screw portions are formed along the axial direction of the work roll 10 in the central portion of the back surface of the cooling water guide plate 20, bolts 26 penetrating the reference beam 24 are screwed into this screw portion, It is supported by a reference beam 24. Also, on the rear surface of the upper and lower ends of the cooling pad 18, a screw screwed to the reference beam 24 is mounted.
The tips of 28 and 30 are engaged with each other so that the cooling pad 18 can be pushed and pulled. Further, the cooling pad 18 and the reference beam 24 are connected by expandable pipe joints 32 and 34 such as bellows. The pipes 32 and 34 are connected to a drainage header 36 and a water supply header 38 through a flow path formed in the cooling pad 18.
Communicates with. Further, the drainage header 36 is in communication with the cooling water flow path 22 through a drainage port 40 formed at the upper end of the cooling water guide plate 20, and the water supply header 38 is provided at the lower end of the cooling water guide plate 20. It communicates with the cooling water flow path 22 through the formed slit nozzle 42. The cooling pad 18 is provided above the cooling water guide plate 20 and above the cooling water guide plate 20, respectively.
There are formed seal portions 44 and 46 that come into contact with.

Behind the reference beam 24, a water supply / drainage block 48, which will be described in detail later, is arranged. The water supply / drain block 48 is suspended on a piston rod 54 of an air cylinder 52 fixed to the upper end of the bracket 50, and has a water supply side pipe end 56 and a drain side pipe end 58.
Are inserted in the reference beam 24. A pin hole 60 is formed in the water supply / drainage block 48, and a pin 64 rotatably supporting the roller 62 is inserted into the pin hole 60.
The pin 64 is biased to the right in FIG. 1 by a spring 66, and the roller 62 is in contact with a base plate 68 provided on the side surface of the bracket 50.

The upper and lower guide plates 70 provided below the cooling pad 18 and the water supply / drainage block 48 have fulcrums 72 fitted in the fitting holes of the bracket 50. A wedge 76 is attached to the upper surface of the upper guide plate 70, and the wedge 76 engages with a hook portion of a rotating arm 78 provided on the upper portion of the bracket 50. Pivoting arm 78
Is rotatably attached to the bracket 50 via a pin 80 and has a weight 82 on the opposite side of the hook portion. Therefore, the turning arm 78 receives a turning force in the clockwise direction in FIG. 1 by the weight 82 with the pin 80 as the turning fulcrum, and the upper guide plate 70 moves in the clockwise direction with the fulcrum 72 as the turning center. A turning force is applied to bring the tip end portion 84 of the upper guide plate 70 into contact with the upper work roll 10.

As shown in FIG. 2, the reference beam 24 is inserted into the guide grooves 90, 92 formed in the bearing boxes 86, 88 that support the upper work roll 10 so that the axial ends of the upper work roll 10 are rotatable. Is
It is attached to the bearing boxes 86 and 88. On the other hand, the water supply / drainage block 4
An engaging groove 94 is formed in the groove 8, and the engaging portion 96 of the bracket 50 engages with the engaging groove 94 so that the water supply / drainage block 48 and the bracket 50 can move integrally. A cylindrical coupling protrusion 98 is formed on the front surface of the water supply / drainage block 48, and the coupling protrusion 98 is fitted into a coupling hole formed in the reference beam 24.

The bracket 50 supporting the water supply / drainage block 48 is a third
It is fixed to the bracket 100 as shown. The bracket 100 supports via a spring 104 a water supply / drainage block 102 similar to the water supply / drainage block 48 for cooling the lower work roll. A lower guide plate 108 fixed to the bracket 100 is located above the cooling pad 106 and the water supply / drainage block 102 provided in contact with the lower work roll 12, and further, on the bracket 100 behind the lower guide plate 108. A fixed guide plate 110 is arranged. The bracket 100 is connected to the piston rod 114 of the cylinder 112,
In accordance with the operation of 112, the upper and lower work rolls 10 and 12 are moved back and forth to disengage the water supply / drainage blocks 48 and 102 from the reference beams 24 and 116, and are also coupled to the reference beams 24 and 116.

Two water supply pipes 118 and 120 and drain pipes 122 and 124 are connected to the water supply and drainage blocks 48 and 102, respectively, as shown in FIG. The reference beams 24 and 116 are arranged with one end side (the right side in FIG. 4) having a minute gap with the bearing box to prevent interference with the bearing box due to thermal expansion. In Figure 3
117 is a mill housing that supports the work rolls 10 and 12 of the rolling mill.

The operation of the embodiment configured as described above is as follows.

The cooling water for cooling the upper work roll 10 is guided to the water supply / drainage block 48 via the water supply pipe 118, and enters the water supply header 38 from the water supply side pipe end 56 of the water supply / drainage block 48 via the pipe joint 34.
Thereafter, the cooling water is sprayed from the slit nozzle 42 onto the surface of the upper work roll, cools the upper work roll 10 while rising in the cooling water passage 22, and enters the drainage header 36 through the drainage port 40.
Further, the cooling water enters the pipe joint 32 of the drainage header 36, is guided to the water supply / drainage block 48 via the drainage side pipe end 58, and is drained to the drainage pipe 12.
It is released to the outside via 2. The lower work roll 12 is cooled in the same manner.

Roll rearrangement for work roll abrasion and the like due to wear of the work roll is performed as follows. First, the cylinder 112 shown in FIG.
When the cylinder is retracted to the cylinder 112 side, the bracket 100 fixed to the piston rod 114 moves to the right in FIG. For this reason, the water supply / drain block 102 and the lower guide plate 10 for cooling the lower work roll 12 attached to the bracket 100.
8. With the guide plate 110, the water supply / drainage block 48 for cooling the upper work roll 10 supported by the bracket 50 integral with the bracket 100 and the upper guide plate 70 move rightward in FIG. 3 together with the bracket 100. As a result, the water supply / drainage block 4
The connection between 8,102 and the reference beams 24,116 is released, and the water supply / drainage blocks 48,102 are carried out of the mill housing 117 with the water supply pipes 118,120 and the drainage pipes 122,124 connected. After that, the upper and lower work rolls are moved by the rearrangement carriage guided by the rearrangement guide rails not shown
Cooling pads 18,106 and reference beams 24,116 on bearing housing
In the state where and are attached, they are carried out of the mill housing 117. Then, for example, when the upper work roll 10 is replaced with a new upper work roll, the curvature of the cooling water guide plate 20 can be adjusted by adjusting the screw 28, 30 to obtain an appropriate cooling water passage 22. it can. further,
After assembling the upper and lower work rolls 10 and 12 into the mill housing 117, the cylinder 100 is advanced by the cylinder 112 to couple the water supply / drainage blocks 48 and 102 to the reference beams 24 and 116, and the upper guide plate 70, the lower guide plate 108, and the guide plate. Place 110 in place.

As described above, in the present embodiment, by adjusting the bolt 26, the position of the cooling water guide plate 20 with respect to the work roll can be adjusted, and furthermore, by pushing and pulling the cooling water block 18 by the screws 28 and 30, The curvature of the cooling water guide plate 20 can be changed according to the diameter of the work roll, the cooling water passage 22 can be appropriately maintained, and the work roll can be sufficiently cooled. In addition, the deformation of the cooling water guide plate 20 uses the reference beam attached to the bearing box of the work roll as the reference position for the amount of deformation, so that the cooling water guide plate can be accurately set with respect to the work roll. Moreover, since the reference beam and the cooling pad are connected by using an expandable tube joint,
It is possible to cope with the deformation of the cooling water guide plate 20 (deformation of the cooling pad 18) and to smoothly supply and drain water. Further, in the above embodiment, the water supply / drainage blocks 118, 120 and the water supply / drainage blocks 48, 102 to which the drainage pipes 122, 124 are connected are advanced and retracted integrally with the upper guide plate 70, the lower guide plate 108, and the guide plate 110 to cool the cooling plates 18, 1.
Since the 16 and the water supply / drainage blocks 48 and 102 are connected and disconnected, the roll reassembling work can be easily performed.

The operation of thinning both ends of the cooling water guide plate 20 in the present embodiment and making the central part thicker will be described below with reference to FIG. When the y-axis is taken downward with the upper end portion 20a of the cooling water guide plate 20 as a reference point, the moment M acting on the cooling water guide plate 20 is M = y · W. W in this equation is the deformation force of the guide plate 20. Due to this moment M, the guide plate 20 is bent according to the following equation (1).

However, E: Young's modulus, B: plate width, h: plate thickness, ρ: bending radius of curvature.

In order to keep ρ constant in equation (1), yW / EI
Must be constant. Here, since W and E are constant values, y / I may be constant. Equation from I = Bh ^3/12 is obtained.

y / I = 12y / Bh ³ Since B has a constant value in this equation, it is only necessary to keep y / h ³ constant.

If y / h ³ = K (constant value), According to the equation (2), ρ can be made constant by increasing the plate thickness with the cube root of y.

If the thickness of the guide plate 20 at a position of y = y _a and y = y _b, respectively and h _a and h _b in Figure 5 Becomes

Here, for example, if y _a = 50 mm, h _a = 3 mm, y _b = 220 mm, Becomes

By increasing the plate thickness h along with y in this way, the bending curvature radius ρ of the guide plate 20 becomes substantially constant, and it is possible to perform deformation that is almost circular.

As described above, according to this embodiment, when the cooling water guide plate facing the surface of the work roll is forcibly deformed by the push-pull adjustment mechanism provided on the reference beam, the work roll and the cooling water guide The gap between the plate and the plate can be kept almost constant, and compensation and tracking can be ideally performed even for a large change in roll diameter.

In the above-described embodiment, the operation of the bolt 26 was described as a case of simply supporting the cooling pad 18, but the bolt 26 is configured like a screw 28, 30 so that it can be used for adjusting the cooling water passage 22. Good. Further, although the four-high rolling mill has been described in the above embodiment, it goes without saying that it can be applied to a six-high rolling mill.

〔The invention's effect〕

As described above, according to the present invention, even if the roll diameter is largely deformed due to cutting or the like, the gap between the roll and the cooling water guide plate can be made substantially constant in the circumferential direction, and the roll is sufficiently Can be cooled to.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a roll cooling device for a rolling mill according to the present invention, FIG. 2 is a plan view of the embodiment, and FIG. 3 is a rolling mill equipped with the cooling device of the embodiment. FIG. 4 is a sectional view showing a main part, FIG. 4 is a front view showing an example of the water supply / drainage block of the embodiment, and FIG. 5 is a sectional view showing a modification of the cooling water guide plate of the embodiment. 10 …… Upper work roll, 12 …… Lower work roll, 14 …… Rolled material, 16 …… Cooling device, 18 …… Cooling pad, 20 …… Cooling water guide plate, 22 …… Cooling water flow path, 24 …… Reference beam, 28,3
0 …… screw, 36 …… drainage head, 38 …… water supply head, 48,102 …… water supply / drain block, 50,100 …… bracket, 56 …… water supply side pipe end, 58 …… drainage side pipe end, 70 …… upper guide plate , 108 …… Lower guide plate, 110 …… Guide plate, 112…
…Cylinder.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-58-47502 (JP, A) JP-A-55-24774 (JP, A) JP-A-54-83657 (JP, A) JP-A 61- 266108 (JP, A) JP 61-266109 (JP, A)

Claims (1)

[Claims] 1. A cooling water guide plate provided in the vicinity of a roll of a rolling mill and having a curved surface along the circumferential direction of the roll, and cooling water in a cooling water passage formed by the cooling water guide plate and the roll. A water supply member to be supplied, a drainage member for draining the cooling water supplied by the water supply member, a support member supporting the cooling water guide plate at a central portion, and upper and lower end positions of the cooling water guide plate are adjusted. In a roll cooling device of a rolling mill having a bending deformation member that changes the curvature of the cooling water guide plate with respect to the diameter of the roll, the curvature of the cooling water guide plate is changed with respect to the diameter of the roll. In this case, the cooling water guide plate is formed such that the thickness of the cooling water guide plate is gradually increased from the vertical end portion toward the central portion so that the radius of curvature of the cooling water guide plate becomes substantially constant. Roll cooling of rolling mill Rejection device.