JP2001087806A - Built-up sleeve roll for rolling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a built-up sleeve roll for rolling with which problems caused by a conventional method for fixing the sleeve are dissolved. SOLUTION: In the built-up sleeve roll for rolling which is formed by fixing a hollow cylindrical sleeve consisting of a material excellent in wear resistance or the like to a roll shaft consisting of a tough material coaxially and rotatably as one body together with the roll shaft, the sleeve is fit on and fixed to the roll shaft and also a key for preventing slip is provided between the side face of the sleeve and the roll shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a roll sleeve made of a material having excellent abrasion resistance, seizure resistance, rough surface resistance and the like, fitted and fixed to the outer periphery of a roll shaft made of a tough material. The present invention relates to an assembling type roll for rolling.

[0002]

2. Description of the Related Art As a fixing system in which a hollow sleeve is coaxially rotatable on the outer periphery of a roll shaft and is rotatable integrally with the roll shaft,
Conventionally, the shrink fitting method has been dominant, and there is a method in which a key is provided on a fitting surface and torque is transmitted by the key.

FIG. 5 shows an example of a conventional assembling sleeve roll for rolling according to a conventional shrink fitting method. FIG. 5 is a partial cross-sectional front view. In FIG. 5, a rollable assembling sleeve roll 51 has a hollow sleeve 53 fitted around the outer periphery of a roll shaft 52 by shrink fitting. In this method, the torque is transmitted only by the frictional resistance torque of the shrink-fitting surface, and is employed in various applications such as a coarse compact mill roll for rods and a mandrel mill roll for pipes. The sleeve 53 is made of a roll material having excellent abrasion resistance, seizure resistance, surface roughness resistance, and the like. A concave deep caliber 54 may be formed on the outer periphery of the sleeve 53. The roll shaft 52 is made of an alloy material having toughness. A part of the outer periphery of the roll shaft 52 has a convex flange 5 serving as a stopper when the sleeve 53 is fitted.
5 are provided. Reference numeral 56 denotes a material to be rolled.

FIG. 6 shows an example of a conventional assembling type sleeve roll for rolling by a key method. FIG. 6A is a partial cross-sectional front view, and FIG. 6B is a view taken in the direction of arrows BB in FIG. 6A. In FIG. 6, the assembling-type sleeve roll 61 for rolling is used.
Is fitted with a hollow sleeve 63 on the outer periphery of the roll shaft 62 and fixed by a key 64. In this case, torque is transmitted only by keys on the fitting surface, and is used for, for example, a reducer roll for pipes. As in the case of FIG.
A caliber 65 is provided on the outer periphery of 3, and a stopper flange 66 is provided on the outer periphery of the roll shaft 62.

[0005]

The rollable assembling sleeve roll according to the shrink fitting method as shown in FIG. 5 has the following problems. Coarse compact mill rolls for rod wire usually have one caliber in many cases.The sleeve length is short, and the caliber is relatively large and deep, so the mechanical load and thermal shock load are severe. It is. For this reason, unless the shrink fitting rate is significantly higher than usual, safety against slippage cannot be ensured. On the other hand, if the shrink fitting ratio is too high, there is a problem that the inner surface of the sleeve is broken or a crack is generated from the bottom surface of the caliber, resulting in breakage.

[0006] The assembling sleeve roll for rolling by the key method as shown in FIG. 6 has the following problems. Since the key is provided on the fitting surface between the sleeve and the roll shaft, stress concentrates on the R portion at the bottom of the key groove on the inner surface of the sleeve. For this reason, in applications in which a mechanical load or a thermal shock load is severe, such as a coarse compact mill roll for a rod wire, a crack is easily generated from the R portion at the bottom of the key groove, and cracks are easily caused. Therefore, there is a problem that the mechanical load and the thermal shock load, such as a reducer roll for pipes and a straightening roll for section steel, are limited to applications where the load is relatively light.

It is an object of the present invention to provide a rollable assembling sleeve roll which can solve the problems of the conventional sleeve fixing method.

[0008]

According to the present invention, there is provided an assembling-type sleeve roll for rolling, wherein a hollow cylindrical sleeve made of a material having excellent abrasion resistance and the like is coaxially and rolled on a roll shaft made of a tough material. A rollable assembly sleeve roll fixed so as to be integrally rotatable with the sleeve, the sleeve and the roll shaft are fitted, and a key for preventing slippage is provided between the sleeve side surface and the roll shaft.

In the present invention, the sleeve and the roll shaft are fitted by shrink-fitting or a combination of adhesive and shrink-fitting, and the shrink-fitting rate is determined by the shearing of the shrink-fitting surface and the frictional resistance torque being at least the torque at the time of normal rolling. It is characterized in that it can withstand the torque of the motor at the maximum time by both the shear and friction resistance torque of the shrink-fitting surface and the shear resistance torque of the anti-slip key.

[0010] Further, the present invention is characterized in that the slip prevention key fitting portion and a predetermined width near the key fitting portion are clearance-fitted. Furthermore, it is characterized in that the side surfaces of the anti-slip key are subjected to induction hardening.

[0011]

According to the roll sleeve assembly type roll of the present invention, the sleeve and the roll shaft are fitted by shrink fitting or the like.
Since it is fixed by the anti-slip key provided between the side of the sleeve and the roll shaft, safety against slip of the sleeve can be ensured, and the R at the bottom of the anti-slip key groove on the side of the sleeve can be secured.
Since the stress is not largely concentrated on the portion, it is possible to prevent the occurrence of cracks and breakage from the R portion at the bottom of the keyway for slip prevention. Accordingly, the present invention can be applied to a roll for a coarse compact mill for rods and a mandrel mill roll for a pipe, which are applications that are severe in mechanical load and thermal shock load.

In the present invention, when the sleeve and the roll shaft are fitted by shrink fitting, the shrink fitting ratio is set so that the frictional resistance torque can withstand at least the normal rolling torque. If an impact torque is generated at the time of biting or the like, the impact torque is greatly reduced by the frictional resistance of the shrink-fitting surface. Only the overtorque exceeding the torque acts and can be kept low. Therefore, it is possible to prevent the occurrence of cracks and breakage from the R portion at the bottom of the keyway for slip prevention on the side surface of the sleeve.

[0013] The shrinkage of the fitting surface between the sleeve and the roll shaft can be made relatively small as long as it can withstand the normal rolling torque. Therefore, the tensile stress in the circumferential direction on the sleeve surface is small, so that safety against cracks and breakage from the sleeve surface is improved.

Further, since the slip-preventing key fitting portion and a predetermined width (10 to 30 mm) in the vicinity thereof are not shrink-fitted but are clearance-fitted, they are generated at the R portion at the bottom of the slip-preventing key groove on the side surface of the sleeve. Circumferential tensile stress is greatly reduced,
Crack generation and breakage from the R portion at the bottom of the key groove can be prevented.

Further, by performing induction hardening on the side surface of the anti-slip key, sag and deformation due to surface pressure applied by torque during rolling can be prevented. 55-70HS is desirable for induction hardening.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 shows a first embodiment of a rollable assembling sleeve roll according to the present invention. FIG. 1 (a)
Is a partial cross-sectional front view, and FIG. 1 (b) is AA in FIG. 1 (a).
It is an arrow view. In FIG. 1, a rollable assembling sleeve roll 1 is a coarse compact mill roll for rods.

The hollow sleeve 2 is made of a roll material having excellent wear resistance and the like. One concave deep caliber 3 was formed on the outer periphery of the sleeve 2 having a relatively short body length. Further, two key grooves 4 are provided on the inner peripheral side of the side surface of the sleeve 2, and a total of four key grooves 4 are provided on both side surfaces.

The solid roll shaft 5 is made of a tough steel alloy or the like. Four key grooves 6 are provided on the outer periphery of the roll shaft 5 so as to correspond to the key grooves 4 on the sleeve 2 side.

A sleeve 2 is provided on the outer periphery of the roll shaft 5.
Was shrink-fitted at a shrink-fitting rate set so as to be able to withstand the torque during regular rolling. At this time, the overhang 10 provided at the center of the fitting surface between the sleeve 2 and the roll shaft 5 serves as a stopper when shrink-fitting.
Did not slip in the direction of the rotation axis. At the time of shrink fitting, a friction increasing agent was interposed on the fitting surface between the sleeve 2 and the roll shaft 5.

After shrink fitting, an anti-slip key 7 having an L-shaped cross section is inserted between the key groove 4 on the sleeve 2 side and the key groove 6 on the roll shaft 5, and the anti-slip key 7 is set by a set screw 8. It was fixed to the roll shaft 5. Thereafter, a fillet ring 9 was attached to the neck portion of the roll shaft 5 by shrink fitting to obtain a rollable assembling sleeve roll 1 of the present invention.

In this embodiment, the anti-slip key 7 is
With respect to the over torque exceeding the torque at the time of regular rolling (= the torque at the time of the emergency maximum of the motor−the torque at the time of regular rolling), the allowable surface pressure is set so that the side of the slip preventing key 7 does not set or deform. The size and number of the anti-slip keys 7 were designed to be about 20 kg / mm ² or less.

The anti-slip key 7 is made of a material having strength and toughness higher than SCM440.
Was subjected to induction hardening (55 to 70 HS). Further, it is desirable that the R dimension at the bottom of the keyway 4 on the sleeve 2 side be set to R8 or more in order to reduce stress concentration.

Further, as shown in FIG. 2 which is an enlarged view of the fitting portion in FIG. 1A, the fitting portion of the anti-slip key 7 and its width of about 20 mm, that is, Y = (key The length of the fitting portion 7) is about 0.1 mm.
A clearance S of 0.15 mm was provided for clearance fit.

With the above-described structure, even if an impact torque is applied due to biting during rolling or the like, the friction is reduced by the frictional resistance of the shrink-fitting surface, so that the impact torque does not act directly on the anti-slip key 7. . In addition, the key 7 for slip prevention
Since the gap between the fitting portion and the vicinity thereof has a clearance of about 20 mm, the stress generated in the R portion of the bottom of the key groove 4 on the sleeve 2 side can be suppressed to a relatively small value. Breakage can be prevented.

On the other hand, the sliding resistance of the sleeve 2 can be sufficiently tolerated by the frictional resistance torque of the shrink-fitting surface and the shear resistance torque of the anti-slip key 7. Also,
Since the overhang 10 is provided, sufficient safety can be ensured against slippage in the rotation axis direction.

(Embodiment 2) FIG. 3 shows a second embodiment of the assembled sleeve roll for rolling according to the present invention. FIG. 3 is a partial cross-sectional front view. In FIG. 3, the assembling-type sleeve roll 31 for rolling is a rough work roll for hot rolling under very severe rolling conditions.

The hollow sleeve 32 has a composite structure in which an outer layer material of a high-speed alloy having excellent wear resistance and the like is metallically joined to the outer periphery of a tough inner layer material by a centrifugal casting method, a build-up casting method, or the like. It is a sleeve. Sleeve 32 on roll shaft 35
Is fitted by shrink-fitting, and an anti-slip key 37 having an L-shaped cross section is inserted between the key groove 34 on the sleeve 32 side and the key groove 36 on the roll shaft 35 side. Was fixed to a roll shaft 35. 39 is a material to be rolled, and 40 is a backup roll.

In the case of this type of roll, since the sleeve has been conventionally fixed only by the shrink-fitting method, stress remains at the joint between the outer layer material and the inner layer material of the sleeve, which may cause fatigue fracture from immediately below the joint. In addition, there is a risk of cracks and breakage from the inner surface or the surface of the sleeve. Therefore, the shrink fitting rate could not be increased, and it was necessary to minimize the shrink fitting rate. According to the configuration of the example, the shrink-fitting ratio can be reduced by at least 20% or more compared with the related art, and the safety against breakage or slip of the sleeve 32 can be sufficiently secured.

(Embodiment 3) FIG. 4 shows a third embodiment of the assembled sleeve roll for rolling according to the present invention. FIG. 4 is a partial cross-sectional front view. In FIG. 4, the hollow sleeve 42
HIP is applied to the outer periphery of a tough steel inner layer material, and the outer layer material of a high-speed sintered alloy excellent in wear resistance,
It is a composite structure that is diffusion bonded by a sintering method.

The hollow sleeve 42 was shrink-fitted to the roll shaft 43, and a key 44 for preventing slippage was provided only on one side of the sleeve 42.

The assembling type roll 4 for rolling according to the present embodiment.
1 indicates that the number of slip prevention keys 44 is only on the drive side and
Can withstand enough at each point. In addition, since the thrust ring 45 is brought into contact with the slip prevention key 44, a set screw for fixing the key 44 is not required. The size and number of the anti-slip keys or fixing with set screws may be changed according to the shape of the roll, the application, the load conditions, and the like.

[0033]

According to the present invention, the assembly-type sleeve roll for rolling can be applied to an application where a mechanical load or a thermal shock load is severe, which was difficult to apply in the past. A high roll can be provided, and an improvement in the roll basic unit can be expected.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of an assembled sleeve roll for rolling according to the present invention.

FIG. 2 is an enlarged view of a fitting portion in FIG.

FIG. 3 shows a second embodiment of the rollable assembling sleeve roll of the present invention.

FIG. 4 shows a third embodiment of the assembled sleeve roll for rolling according to the present invention.

FIG. 5 shows an example of a conventional assembling sleeve roll for rolling by a shrink-fitting method.

FIG. 6 shows an example of a conventional assembling sleeve roll for rolling by a key method.

[Explanation of symbols]

1 Assembled sleeve roll for rolling, 2 sleeve,
Reference Signs List 3 caliber, 4 keyway, 5 roll shaft, 6 keyway, 7 anti-slip key, 8 set screw, 9 fillet ring, 10 overhang, 11 rolled material, 31 rollable sleeve roll for roll, 32 sleeve, 33 Flange, 34 keyway, 35 roll shaft, 36 keyway, 37 anti-slip key, 3
8 Set screw, 39 Rolled material, 40 Backup roll, 41 Assembled roll for roll, 42
Sleeve, 43 Roll shaft, 44 Anti-slip key, 45 Thrust ring 51 Rollable assembly roll for roll, 52 Roll shaft, 53 Sleeve, 54
Caliber, 55 Flange, 56 Rolled material, 6
1 Rollable assembly sleeve roll, 62 roll shaft,
63 sleeve, 64 keys, 65 caliber,
66 Flange, length of fitting part of H key 7, S clearance

Claims (5)

[Claims] 1. A rollable assembling sleeve roll in which a hollow cylindrical sleeve made of a material having excellent wear resistance and the like is fixed to a roll shaft made of a tough material so as to be coaxial and rotatable integrally with the roll shaft. 2. The rollable assembling sleeve roll according to claim 1, wherein the sleeve and the roll shaft are fitted, and a key for preventing slippage is provided between the sleeve side surface and the roll shaft. 2. A sleeve and a roll shaft are fitted by shrink fitting, and the shrink fitting ratio is set so that the friction resistance torque of the shrink fitting surface can withstand at least the torque at the time of normal rolling. 2. The assembling sleeve roll for rolling according to claim 1, wherein both the frictional resistance torque and the shear resistance torque of the anti-slip key can withstand the torque of the motor at the time of an emergency maximum generated at the time of biting or the like. . 3. The rollable assembling sleeve roll according to claim 2, wherein an adhesive is interposed between the fitting surfaces of the sleeve and the roll shaft and shrink-fitted. 4. A clearance fit between a slip-fitting key fitting portion and a predetermined width in the vicinity thereof.
Or the assembling type roll for rolling according to 3. 5. The rollable assembling sleeve roll according to claim 1, wherein induction hardening is performed on a side surface of the anti-slip key.