JPH04266469A - Method for cooling roll and cooling roll - Google Patents

Abstract

PURPOSE:To solve the temperature un-uniformity of longitudinal direction of the roll of surface skin just under cooling type. CONSTITUTION:The cooling roll 20 cools the roll by providing the cooling holes 3 just under the surface skin of the roll and makes the cooling water to flow in the above cooling hole. The cooling holes are divided by mutually connecting every other hole to two groupes of mutually independent cooling water systems, then the cooling water is made to flow in the above cooling water system to the mutually reverse directions. In such a way, the bent of roll is reduced, the life of roll is prolonged and the roll cost can be reduced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cooling rolls used in continuous casting equipment, continuous annealing furnaces, etc., and to cooling rolls.

0002

2. Description of the Related Art Conventionally, since the rolls of continuous casting equipment are exposed to high temperatures, a method has been used to cool them by flowing cooling water inside the rolls. In particular, due to the increase in thermal load on rolls due to high-speed casting and high-temperature extrusion in recent years, there is an increasing need to strengthen the cooling of the rolls in order to prevent internal cracking due to increased roll bending and to extend the life of the rolls.

[0003] All conventional rolls employ a method in which cooling holes are provided directly under the skin of the roll to actively cool the vicinity of the contact surface with the slab.

[0004] In these conventional cooling rolls directly under the skin,
In either method, the temperature of the roll can be lowered. However, if the temperature rise of the cooling water increases accordingly and the average temperature of the cooling water on the outlet side exceeds 60°C, a partial boiling phenomenon will occur near the cooling water outlet at the contact area between the water and the inner surface of the roll, and the cooling capacity will decrease. It's falling.

[0005] In this case, in these conventional roll structures, all the cooling water flowing into each cooling hole flows in the same direction, so the difference in roll temperature between the cooling water inlet side and the outlet side becomes large, resulting in uneven heat. There is a problem in that roll bending is difficult to completely eliminate. In terms of roll life, heat cracks frequently occur near the cooling water outlet side due to insufficient cooling, which is an impediment to extending life or reducing roll cost.

[0006]

[Problems to be Solved by the Invention] The problems to be solved by the present invention are to eliminate the temperature unevenness in the longitudinal direction of a roll cooled just below the skin, reduce roll bending, extend the life of the roll,
The aim is to reduce roll costs.

[0007]

[Means for Solving the Problems] A method for cooling a roll according to the present invention is a method in which a cooling hole is provided directly under the skin of the roll, and cooling water is allowed to flow through the cooling hole to cool the roll. The above-mentioned problem is solved by dividing the system into two groups of mutually independent cooling channel systems which are communicated with each other at intervals, and by means of flowing cooling water into the cooling channel systems in opposite directions.

[0008] The cooling roll of the present invention has cooling holes provided directly under the skin of the roll and cools the roll by flowing cooling water through the cooling holes. , a mutually independent cooling water supply channel and a cooling water drainage channel are provided at both ends of the arbor, and every other cooling hole is communicated with each other to be divided into two mutually independent groups, and one group is connected to the A cooling water supply channel provided at one end of the arbor communicates with a cooling water drainage channel provided at the other end of the arbor, and the other group is connected to a cooling water drainage channel provided at one end of the arbor and another group of the arbor. The above problem is solved by a means that communicates with the cooling water supply channel provided at the end.

[0009]

[Function] Since each sub-skin cooling roll has a plurality of cooling holes, we focused on the fact that by reversing the direction of flow of cooling water in adjacent cooling holes, the roll temperature could be made uniform as a whole. In order to embody this basic idea,
The following points were devised for the roll structure.

[0010] 1. Since the flow direction is two directions and a water supply and drainage mechanism is required on both sides of the roll, each roll has a double pipe structure.

[0011] 2 However, since it is impossible to create a double pipe structure in one piece due to the production of rolls, a structure was adopted in which the pipes are later assembled into the manufactured roll.

As described above, in the roll of the present invention, cooling water is alternately flowed in opposite directions to adjacent cooling holes among the plurality of cooling holes, so that temperature unevenness in the longitudinal direction of the roll is reduced.
A more uniform roll temperature can be achieved.

[0013]

EMBODIMENTS Referring to FIGS. 1 and 2, embodiments of the roll cooling method and cooling roll of the present invention will be described.

[0014] The roll cooling method of the present invention
In the method of cooling the roll 20 by providing cooling holes 3 directly under the skin of the cooling hole 3 and letting cooling water flow through the cooling hole 3, two groups of mutually independent cooling water channel systems in which every other cooling hole 3 is communicated with each other. The cooling water is divided into two, and the cooling water flows in opposite directions through these cooling waterway systems.

As shown in FIGS. 1 and 2, the cooling roll 20 of the present invention is provided with groove-shaped cooling holes 3 and strip-shaped mutual contact portions 4 on the outside of the roll arbor 2, and a strip-shaped mutual contact portion 4 between the sleeve 1 and the arbor 2 is provided. This is an example in which the mutual contact portions 4 are fixed by shrink fitting.

A water supply and drainage conduit 9 consisting of a pipe 6, a small flange 7 and a large flange 8 is fixed to the roll arbor 2 with bolts 10 at the water supply and drainage ports 5 at both ends. O-ring grooves 11 are cut into both flanges, and water is sealed with the O-ring 12. The water from the left side of the roll is supplied from multiple holes 13 drilled around the circumference of the large flange, passes through the outer cooling water pipe, the water supply hole 14, the cooling hole 3, and then passes through the right drainage hole 15 to the inside of the right side. It passes through the cooling water pipe and is drained from the center of the roll.

From the right side, water supplied from the outer cooling water pipe is similarly discharged along the broken line route in FIGS. 1 and 2.

In the above embodiment, the cooling holes 3 are provided on the outside of the arbor 2, but they may be provided on the inside of the sleeve 1. The cooling holes 3 may be the even number of spiral grooves described above. Cooling water may be supplied from the inside and drained from the outside.

As a result of applying the roll of this embodiment to a pinch roll for actual continuous casting, the difference in surface temperature between the left end and right end of the roll was 30°C or less, which was 100 to 150°C compared to the conventional type.
It is significantly smaller than ℃.

[0020]

[Effects of the Invention] By using the cooling roll of the present invention, temperature non-uniformity in the longitudinal direction of the roll is eliminated, internal cracking of slabs is reduced due to reduction in roll bending, and roll cost is reduced due to extension of roll life. There is.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a cooling roll of the present invention.

FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1;

[Explanation of symbols]

1: sleeve,
2: Arbor, 3: Cooling hole,
4: Strip-shaped mutual contact part, 5: Water supply and drainage port,
6: Pipe, 7: Small flange, 8: Large flange, 9: Water supply and drainage pipe, 10
: Bolt, 11: O-ring groove,
12: O-ring 13: Hole, 14: Water supply hole, 1
5: Drain hole, 2
0: Roll, 21: Cooling water.

Claims (2)

[Claims] 1. A method of cooling the roll by providing cooling holes directly under the skin of the roll and letting cooling water flow through the cooling holes, wherein two groups of cooling holes are made to communicate with each other at every other cooling hole are arranged independently of each other. A method for cooling a roll, characterized in that the roll is divided into two cooling water channel systems, and cooling water is flowed in opposite directions through the cooling water channel systems. 2. A cooling roll in which cooling holes are provided directly under the skin of the roll and cooling water is allowed to flow through the cooling holes to cool the roll, wherein the cooling holes are provided in the longitudinal direction between an arbor and a sleeve, and the cooling hole is provided in the longitudinal direction between an arbor and a sleeve. A mutually independent cooling water supply channel and a cooling water drainage channel are provided at both ends of the arbor, and every other cooling hole is communicated with each other to be divided into two mutually independent groups, and one group is provided at one end of the arbor. A cooling water supply channel provided at one end of the arbor communicates with a cooling water drainage channel provided at the other end of the arbor; A cooling roll characterized in that it communicates with a water supply channel.