JPH0471761A - Roll for continuous caster - Google Patents

Abstract

PURPOSE:To prolong the service life of the above roll for continuous caster by arranging zigzag-state continuous groove parts to circular direction of the roll on surface of the roll barrel part. CONSTITUTION:Plural pieces of the slit grooves 1 crossing at the right angle to the roll axis and circulating the roll surface in one round at the fixed intervals to the roll axial direction, are arranged on the roll barrel part 2. Then, the roll for continuous caster is constituted so that crack to the roll circular direction developed on the roll barrel part 2 can progress to the roll circular direction in only the roll barrel part 2 between the adjoining slit grooves 1. Therefore, to the roll circular direction on the roll barrel part 2 surface, the zigzag-state continuous grooves 3 are arranged. By this method, eccentric resistance and relaxation of heat stress in the roll can be combinedly provided.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to continuous caster rolls.

[Prior Art] Continuous casting machine rolls, such as pinch rolls, are repeatedly subjected to thermal stress due to high-temperature cast slabs under high loads, and as a result, cracks occur and propagate. Among these cracks, cracks that propagate in the roll circumferential direction will cause roll breakage if left untreated.

There would be no problem if there was a roll material that would not cause or propagate cracks in continuous casting machine rolls, but there is currently no such roll material, and currently the only way to extend the life of rolls is to slow down the propagation of cracks. This is the best method.

Conventionally, the following methods have been used to delay the growth of cracks in the circumferential direction of the roll as described above.

(1) Method of machining the roll surface ■ Slit grooves continuous in the roll axis direction are provided at regular intervals in the roll circumferential direction. (Applicable to flat rolls) ■Slit grooves facing the roll axis are provided in a staggered manner over the entire roll surface. (Applicable to flat rolls) ■Spiral grooves with the same winding on the left and right sides are provided on the roll surface.

(2) How to improve the welding direction when overlaying the roll surface ■ Weld in the axial direction and align the direction of the heat affected zone with the roll axis direction.

■Weld in a zigzag manner in the circumferential direction of the roll, and make the direction of the heat-affected zone zigzag in the circumferential direction of the roll 6 [Problem to be solved by the invention] However, the conventional method of slowing down the propagation of cracks in the circumferential direction of the roll had the following problems.

(1) Method of machining the roll surface Although this method has the effect of retarding the propagation of cracks, the eccentricity resistance and thermal stress relaxation properties of the roll are poor.

(2) How to improve the welding direction when overlaying the roll surface Although it may be difficult for roll circumferential cracks to pass through the heat-affected zone, it is not effective enough to significantly slow down crack growth. The invention of ``poor eccentricity resistance and thermal stress relaxation'' solves the above-mentioned problems of the conventional technology, slows down the development of roll circumferential cracks, and provides rolls with excellent eccentricity resistance and thermal stress relaxation. The purpose of the present invention is to provide continuous casting machine rolls.

[Means for Solving the Problems] The continuous casting machine roll according to the present invention has a plurality of slit grooves provided in the roll body at regular intervals in the roll axis direction, perpendicular to the roll axis and going around the roll surface. In a continuous casting machine roll configured such that a crack in the roll circumferential direction that occurs in the roll body can develop in the roll circumferential direction only in the roll body between adjacent slit grooves, the roll circumferential crack is formed on the roll body surface. This is a continuous casting machine roll with continuous zigzag grooves in the direction.

[Function] The continuous casting machine roll according to the present invention is provided with a plurality of slit grooves that are perpendicular to the roll axis and circumferentially around the roll surface at regular intervals in the roll axis direction, so that the continuous casting machine roll according to the present invention can prevent In a continuous casting machine roll configured such that cracks in the roll circumferential direction can propagate in the roll circumferential direction only in the roll body between adjacent slit grooves, continuous zigzag-shaped cracks in the roll circumferential direction are formed on the roll body surface. A groove is provided. For this reason, roll circumferential cracks that occur on the roll body surface develop in the roll circumferential direction, but they do not propagate linearly along the circumference, but rather in the zigzag cracks formed on the roll body surface. It develops along the groove. Therefore, compared to the case where there is no zigzag groove on the roll surface, the growth of cracks can be delayed.

Further, since the roll is configured as described above, it goes without saying that the roll has excellent eccentricity resistance and thermal stress relaxation properties.

[Example] A continuous casting machine roll according to an example of the present invention will be explained with reference to FIGS. 1 and 2. Fig. 1 is a side view of the body of a continuous casting machine roll according to an embodiment of the present invention. Multiple slit grooves 1 that go around the surface
is provided so that cracks in the roll circumferential direction that occur in the roll body 2 can propagate in the roll circumferential direction only in the roll body 2 between adjacent slits 1. A lightning-shaped groove 3 is provided on the surface of the roll, which goes around the row in the circumferential direction of the roll. The roll circumferential cracks generated in the roll body 2 propagate along the lightning-shaped grooves 3, so that the crack growth can be delayed compared to a case where the roll surface does not have the lightning-shaped grooves 3.

FIG. 2 is a side view of a roll in which a wave-shaped groove 13 that goes around the roll is provided on the surface of the roll body 2 in place of the lightning-shaped groove 3 in the roll circumferential direction. The wavy groove portion 13 in FIG.
This has the advantage that it is easier to process than the lightning-shaped groove shown in the figure.

In the above-mentioned method for forming lightning-shaped or wavy grooves, initial cracks must be generated preferentially in this groove, so the depth of the groove must be adjusted so that the temperature change that induces thermal stress in this groove is large. The shallower the better, and the sharper the cross section.

It is preferable to form the grooves by pressing a roller having lightning-shaped or wavy protrusions on the surface against the roll surface.

[Effects of the Invention] According to the present invention, the growth of cracks in the roll circumferential direction of a continuous casting machine roll can be delayed, the life of the continuous casting machine roll is extended, and the roll has both eccentricity resistance and thermal stress relaxation property. be able to.

[Brief explanation of the drawing]

FIG. 1 is a side view of the body of a continuous casting machine roll according to one embodiment of the present invention, and FIG. 2 is a side view of the body of a continuous casting machine roll according to another embodiment of the present invention. 1...Slit edge, 2...Roll body, 3.13...
・Groove in roll body.

Claims (1)

[Claims] A plurality of slit grooves are provided in the roll body at regular intervals in the roll axis direction, perpendicular to the roll axis, and circumferentially around the roll surface. A continuous casting machine roll configured to be able to advance in the roll circumferential direction only in the roll body, characterized in that a continuous zigzag groove in the roll circumferential direction is provided on the roll body surface. roll.