Roll Device

Abstract

A roll, for rolling metals or for grinding, comprises (1) a roll ring formed of a metal carbide, on (2) a metallic holder or support means, which latter means consists essentially in a flanged sleeve, on which the roll ring is disposed, with one side face of the same abutting against a peripheral part of the flange of the sleeve, and a co-operating flanged muff threaded onto the sleeve and having a peripheral part abutting against the other side face of the roll ring. Said flanges are so profiled as to leave annular slits on either side of the roll ring, in which slits there is provided a suitable adhesive substance "glueing" the roll ring to the flanges of the support means.

Parent Case Text

This application is a continuation of application, Ser. No. 760,459 filed Sept. 18, 1968 which is now abandoned.

Description

The present invention relates in the first place to rolls for rolling of metals but also to rolls for other purposes, for instance grinding, crushing, etc., the rolls being composed of one or more roll rings, on which the surface for working the material is situated, and a holder part which carries the roll ring or rings, and which can be the roll shaft itself or can be an annular device mounted on the roll shaft.

The purpose of a compound or built-up roll of this sort is usually to be able to use different materials in the roll ring and the holder part, each being made of a material suitable for its function. In doing so, it is usual to make the roll ring or rings of sintered metal carbide and the holder part of steel. Sintered carbide is very suitable for the contact with the material to be worked, as it is hard and has a high wear resistance. Because sintered metal carbide is relatively brittle, it is highly desirable to, if possible, avoid tensile stresses in the material which for instance can be done by forming the roll ring, so that the forces acting thereon do not act in such a direction that the tensile stresses are increased, or by pre-tensioning it so that it initially is subjected to compressive stresses which more or less counterbalance the influence of such forces that raise the tensile stress.

In prior compound rolls the roll ring and its holder have often been provided with cooperating protrusions and recesses in order to involve the roll ring in the rotation of the holder, for instance fixed connections of the claw coupling type and wedge connection type. These modes of coupling cause local tensile stresses in the roll ring, and, moreover, substantially increase the manufacturing cost.

The present invention relates to an improvement in the construction of a compound roll of the type above referred to, characterized by the feature that the roll ring is fastened by means of an adhesive joint at at least one of the two annular holder parts between which it is attached. By making one or both of the co-operating holder parts threaded it is possible to introduce axial compressive stresses in the ring at the time of mounting the roll ring by tightening the co-operating threaded parts thereby counteracting axial tensile stresses which may arise during operation of the roll.

The invention will now be described with greater particularity with reference to the following specific disclosure and to the appended drawing, in which

FIG. 1 shows a section, in the axial plane, of a roll constructed according to the invention;

FIG. 2 illustrates the concept of mounting the roll ring directly on the roll shaft; and

FIG. 3 shows how a plurality of roll rings may be secured together into one composite roll ring.

The roll shown in FIG. 1 consists of a roll ring 10, which is mounted on a holder 11. The holder consists of a bushing sleeve 13, which at one end has a fixed flange 14 and at its other end has a thread 15, on which is threaded a separate flange in the form of a flange muff 12. The roll ring 10 clamped between the flanges 12 and 14, and its cylindrical inside is suitably shaped to precisely match the external cylindrical surface of the bushing sleeve 13, whereby the roll ring is held centered. The holder is adapted to be mounted on a conventional roll shaft (indicated at 16) and driven for instance by clamping or by a key and slot connection with the shaft. The flanges may alternatively be mounted directly on the roll shaft which then substitutes the bushing sleeve 13.

The flanges 12 and 14 have at their inner sides adjacent the periphery inwardly raised portions 17 and 18 which abut against the roll ring 10. In this way there are formed slit-shaped spaces 19 and 20 between the roll ring and the flanges at the inside of the portions 17 and 18.

The compressive force arising between the flanges 12 and 14 and the roll ring 10 provides not only the hereinabove mentioned axial pre-tension but also a certain frictional force which counteracts the turning of the roll ring on the holder. This friction force is, however, not sufficient for ensuring that the roll ring positively rotates with the holder when rolling. As above stated, driving means previously have been used in the form of cooperating projections and recesses. According to the present invention, a sufficient fastening to ensure positive driving of the roll ring is obtained by applying an adhesive between the roll ring 10 and at least one of the flanges 12 and 14. The adhesive is applied in the spaces 19 and 20. In order to stabilize the construction adhesive can suitably be applied also on the thread 15.

In FIG. 2 another embodiment of the invention is shown, where the roll ring 10 is mounted directly on the roll shaft 26. The roll ring is as in FIG. 1 embraced by two flanges, one of which 27 is integral with the shaft, the other 28 forming a separate sleeve on the shaft and clamped by a ring 29 and screws 30. Also in this embodiment the flanges have raised portions 31, 32 on the surfaces that face the ring, so that slits 33, 34 are formed, but in this case the slits are situated peripherically. This has the advantage that in case the carbide ring breaks during rolling, the adhesive in the slits will aid in preventing the pieces from flying about.

FIG. 3 illustrates how a number of roll rings 40, 41, 42 and 43 can be clamped together between two flanges 44 and 45. As earlier described there are raised portions 46 and 47 on the flanges and corresponding slits 48 and 49. Between the rings there are shims 50 forming slits 51 for an adhesive.

Instead of the illustrated annular raised portions on the flange surfaces facing the roll rings there may be an arbitrary pattern of raised portions, for instance radial, forming a corresponding pattern of slits for the adhesive. Instead of having the raised portions on the flanges it is possible to have them on the roll rings, but this is in general more inconvenient, as the carbide in the ring is more difficult to shape.

Instead of having raised portions integral with the flange or the roll ring the desired slit between a flange and a roll ring may be obtained by separate distance pieces as shown at 50 between the rings in FIG. 3. In this case the facing annular surfaces on the ring and the flange are both plane, and a distance piece in the form of an annular plate or thread is inserted between the surfaces. It has been found suitable to use a thread of tungsten or molybdenum between the annular surfaces, because said materials are not easily deformed by the clamping forces.

The described roller is intended for cold or hot rolling of wire or rods. In order to prevent the destruction of the adhesive joint by the heat in hot rolling, it is essential that the rolls are cooled during the rolling, so that the temperature is held relatively low, and preferably does not exceed 100.degree. C. The cooling is important also in order to prevent the sintered carbide ring from bursting because steel has a higher coefficient of thermal expansion than does sintered carbide. In the illustrated case, the roll ring 10 is mounted with accurate fit on the bushing sleeve 13, which in turn is mounted on a common homogeneous steel shaft. By strong heating of the whole structure the roll ring might burst.

For bonding the rolling ring to the holder means there is used a type of adhesive which is suitable for joining together the actual materials. For bonding sintered metal carbide to steel there can be used organic adhesives such as hardenable plastics (e.g., phenolic resin glue, epoxy resin glue and glue having an isocyanate base; also, as well, there can be used mixtures such as epoxy-silicon glue or epoxy-phenyl glue), or thermoplastics (e.g. vinyl resin), or elastomers (e.g. chloroprene, nitrile rubber), or mixtures of two types of glue such as hardenable plastic and thermoplastic (e.g. phenol-vinyl resin) or hardenable plastic and elastomer (e.g. phenol-nitrile rubber). Also inorganic glues can be used, as for instance silicate glue (waterglass-asbestos). Moreover mixtures of organic and inorganic glues can be used, as oxide of lead and polyvalent alcohols. In connection with the illustrated specific example, an adhesive containing in the main a hardenable epoxy resin has been found particularly suitable. It is cured at 100.degree.-200.degree. C. and retains its strength excellently at up to 150.degree. C and to some extent at 200.degree.-250.degree. C. Both heat-hardenable and cold-hardenable types of adhesive may be used.

The thickness of the adhesive joint should be 0.01-0.25 mm, the lower limit being in the illustrated embodiment suitably 0.05 mm, while the upper limit can be 0.20 mm, preferably 0.10 mm. In the illustrated case the thickness of the joint is equal to the thickness of the slits 19 and 20.

Claims

I claim:

1. Roll for rolling, grinding, crushing and the like which comprises

a roll ring holder having two spaced flanges;

a roll ring between the two flanges on the roll ring holder,

the roll ring and the flanges having matching contact surfaces in the main shaped as surfaces of revolution directed transversely to the axis of rotation of the roll;

means for clamping the roll ring between the flanges;

at least one of said contact surfaces having (a) raised portions which abut against the cooperating contact surface and (b) depressed portions which are somewhat spaced from the cooperating contact surface forming a thin slit therewith, and

binder material in said slit,

the roll ring thus being torsionally fixed between the flanges of the roll ring holder solely by the clamping contact between the surface of revolution and the adhesion of the binder material.

2. Roll for rolling, grinding, crushing and the like which comprises

a roll ring holder having two spaced flanges;

a roll ring clamped between the two flanges on the roll ring holder,

the roll ring and the flanges having matching contact surfaces shaped as surfaces of revolution directed transversely to the axis of rotation of the roll;

means for clamping the roll ring between the flanges;

at least one intermediate spacing member disposed between said congruent contact surfaces and forming between the latter a thin slit; and

binder material in said slit,

the roll ring being thus torsionally fixed between said flanges of the roll ring holder by the combined action of the clamping means and of the binder material, the torsional fixation being obtained exclusively by the clamping contact between the surfaces of revolution and the adhesion of the binder.

3. Roll as defined in claim 1, in which the holder device at the same time forms part of the roll shaft of the roll.

4. Roll as defined in claim 1, in which at least one of the flanges, between which the roll ring is mounted, has that annular surface thereof which faces the roll ring formed with a peripherically situated annular surface portion, which surface portion is somewhat raised in the axial direction over the annular surface portion that is situated closer to the center, so that the peripherically situated surface portion abuts against the roll ring, while the surface portion that is situated closer to the center is separated from the roll ring by a slit, which slit contains an adhesive.

5. Roll as defined in claim 1, in which the thickness of the glue joint is 0.01-0.25 mm.