JPH0679727B2 - 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 the processing heat due to plastic deformation from the rolled material, the frictional heat generated between the rolled material and the roll, and the like. Particularly, in the case of hot rolling, the temperature of the rolled material is a high temperature of about 1200 ° C., so that the rolling roll becomes extremely 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. Various attempts have been made to improve this, such as increasing the amount of cooling water or increasing the pressure of cooling water, but there are limits to this, and the rolls could not be cooled sufficiently.

Therefore, a method for greatly improving the above-mentioned insufficient cooling was proposed in Japanese Patent Publication No. 55-12322. In this method according to the prior art, cooling water guides having a shape along the outer circumference of the roll are arranged at a constant interval with respect to the roll, and cooling water is provided in the gap between the cooling water guide and the roll. Forced supply and average heat transfer coefficient of 4
It is about doubled. However, such a prior art also has the following drawbacks.

(1) Since the cooling water guide is arranged very close to the roll, it is necessary to retract the cooling water guide when changing the rolls, which makes the structure complicated and the time required for changing the rolls. It becomes big.

(2) Gap between cooling water guide and roll (cooling water passage)
It is economical to make the cooling water as small as possible (for example, 1 to 5 mm) in order to reduce the amount of cooling water passing therethrough. Then, in order to accurately maintain such an extremely small gap, the cooling water guide must be arranged in a stable state. However, the pipe for supplying the cooling water to the cooling water guide must be flexible because the cooling water guide needs to be retracted as described in (1). However, in a commonly used rubber hose, an eccentric load is applied to the cooling water guide due to its rigidity, and it is difficult to keep the above-mentioned gap constant.

In order to overcome the above-mentioned drawbacks, Japanese Patent Laid-Open No. 54-83658 discloses a rolling roll for forming a cooling header inside and providing a plurality of cooling water jets communicating with the cooling header. There is disclosed a cooling device in which the above cooling pad is supported by a bearing box. Since this cooling device adjusts the cooling water passage off-line between the rolling roll and the cooling pad surface, it can be controlled to an accurate value. However, in the cooling device disclosed in Japanese Patent Laid-Open No. 54-83658, the cooling water is supplied to the cooling pad by using the water supply hole provided through the bearing box. However, when a hole is formed in the box receiving box in this way, the strength of the bearing box decreases. Moreover, there is a drawback that an apparatus for attaching and detaching the external water supply pipe connected to the water supply hole provided in the bearing box is required when the rolls are recombined.

[Object of the Invention]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a roll cooling device for a rolling mill, which can easily attach / detach the water supply / drainage pipe to / from the cooling pad at the time of roll change.

[Outline of Invention]

The present invention is provided with a cooling pad having a cooling water guide plate that is supported at each end in a bearing box of a roll and that is curved along the roll surface and forms a cooling water passage between the roll surface and the roll surface. In a roll cooling device of a rolling mill in which a cooling pad is provided with a water supply header that supplies cooling water to a cooling water passage and a drainage header that discharges the cooling water, a water supply pipe and a drain pipe that are detachably connected to the cooling pad are used. And a cylinder for advancing / retreating the water supply / drainage block with respect to the roll at the time of roll recomposition via a bracket engaging with the water supply / drainage block.

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 an upper work roll and a lower work roll for rolling down the rolled material 14, respectively. Cooling device 16
Is provided in contact with the upper work roll 10, and the lower work roll 12 is also provided with 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 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 has a cooling water passageway between the upper work roll 10 and the upper work roll 10. Forming 22. The cooling pad 18 has a plurality of threaded portions formed along the axial direction of the work roll 10 at the center of the back surface of the cooling water guide plate 20, and a bolt 26 penetrating the reference beam 24 is screwed into this threaded portion. And is supported by the reference beam 24. Also, on the upper and lower end rear surface of the cooling pad 18,
The tips of the screws 28, 30 screwed onto the reference beam 24 are engaged so that the cooling plate 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 pipe joints 32, 34 are in communication with the drainage header 36 and the water supply header 38 via a flow path formed in the cooling pad 18. 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 with a cooling water guide plate 20.
Sealing portions 44 and 46 that contact the upper work roll 10 are formed above and below, respectively.

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.

An upper guide plate 70 provided below the cooling pad 18 and the water supply / drainage block 48 has a fulcrum portion 72 fitted in a fitting hole 74 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 a water supply / drain block 102 similar to the water supply / drain block 48 for cooling the lower work roll via a spring 104. 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. Reference numeral 117 shown in FIG. 3 is a mill housing.

Two water supply pipes 118, 120 and two drainage pipes 122, 124 are connected to the water supply / drainage blocks 48, 102, respectively, as shown in FIG. The reference beams 24 and 116 are arranged so that one end side (the right side in FIG. 4) has a minute gap with the bearing box, and interference with the bearing box due to thermal expansion is prevented.

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 rail (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 further, by pushing and pulling the cooling pad 18 by the screws 28 and 30, the work can be performed. The curvature of the cooling water guide plate 20 can be changed according to the diameter of the 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. Further, since the reference beam and the cooling pad are connected with each other by using an expandable pipe 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 48, 102 to which the water supply pipes 118, 120 and the drainage pipes 122, 124 are connected are the upper guide plate 70 and the lower guide plate.
108, the guide plate 110 together with the forward and backward movement, cooling pads 18,116
Since the connection and disconnection between the water supply / drainage block 48 and the water supply / drainage block are performed, the roll rearrangement work can be easily performed.
Further, in this embodiment, since the water supply pipe and the drain pipe are connected to the water supply / drain block supported by the bracket,
Cooling water passage 22 without giving an unbalanced load to the cooling pad.
Can always be kept properly.

The roll cooling device shown in the examples is suitable for use in a hot tandem strip mill. This hot tandem strip mill has a thickness of 1.2 to 12 mm and a width of 900
A strip of ~ 1600mm is rolled at a maximum speed of 1200m / min. And the hot tandem strip mill is
Comprised of 6 to 7 rolling mills, diameter 600 to 700 mm,
A rolling roll with a body length of 1800 mm is used.

When the above embodiment is applied to a thick plate mill having a work roll diameter of 1200 mm, the number of screws for pushing and pulling the cooling pad 18 can be further added. For example, the effect can be improved by providing a screw between the bolt 26 and the screw 28 and between the bolt 26 and the screw 30. Further, in the above-described embodiment, the operation of the bolt 26 is described as a case of simply supporting the cooling pad 18, but the bolt 26
May be configured like the screws 28 and 30 so that it can be used also for adjusting the cooling water passage 22. Furthermore, the thickness of the cooling water guide plate 20 may be partially changed to make it easier to deform.

〔The invention's effect〕

As described above, according to the present invention, the water supply / drainage pipe of the cooling pad can be easily attached / detached when the roll is reassembled.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a roll cooling device according to the present invention, FIG. 2 is a plan view of the embodiment, and FIG. 3 is a sectional view showing a main part of a rolling mill equipped with the cooling device of the embodiment. Figure, 4th
The drawing is a front view showing an example of the water supply / drainage block of the embodiment. 10 …… Upper work roll, 12 …… Lower work roll, 14 …… Rolling machine, 16 …… Cooling device, 18 …… Cooling pad, 20 …… Cooling water guide plate, 22 …… Cooling water passage, 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.

Front Page Continuation (72) Inventor Sakae Nishimura 3-1-1 Sachimachi, Hitachi City, Ibaraki Hitachi Ltd. Hitachi factory (56) References JP-A-55-24774 (JP, A) JP-A-SHO 58-47502 (JP, A) JP-A-61-266108 (JP, A) JP-A-61-266110 (JP, A) JP-B-55-12322 (JP, B2)

Claims (1)

[Claims] 1. A cooling pad having a cooling water guide plate which is supported by a bearing box of the roll at each end and which is curved along the roll surface and forms a cooling water passage between itself and the roll surface. In a roll cooling device of a rolling mill, wherein a water supply header for supplying cooling water to the cooling water passage and a drainage header for discharging the cooling water are formed in the cooling pad, a water supply pipe detachably connected to the cooling pad. And a cylinder for advancing and retracting the water supply / drainage block with respect to the roll at the time of roll rearrangement via a blanket engaging with the water supply / drainage block, the water supply / drainage block communicating via the water discharge pipe. Roll cooling device.