Abstract: The present invention provides a composite roll for rolling including an outer layer having excellent wear resistance, surface roughening resistance, crack resistance, and accident resistance due to segregation of MC carbides being suppressed to adjust the amount of graphite to be crystallized. The composite roll for rolling of the present invention is a composite roll for rolling that has an outer layer and is produced through centrifugal casting, and the outer layer contains C in an amount of 2.2 mass % to 3.2 mass %, Si in an amount of 1.0 mass % to 3.0 mass %, Mn in an amount of 0.3 mass % to 2.0 mass %, Ni in an amount of 3.0 mass % to 7.0 mass %, Cr in an amount of 0.5 mass % to 2.5 mass %, Mo in an amount of 1.0 mass % to 3.0 mass %, V in an amount of 2.5 mass % to 5.0 mass %, Nb in an amount of more than 0 mass % and 0.5 mass % or less, and a remaining portion including Fe and inevitable impurities, and a condition (a): Nb mass %/V mass %<0.1, and a condition (b): 2.1×C mass %+1.

Abstract: Guide device for rolling long metal products, comprising at least a pair of guide rolls coplanar with each other and rotatable round axes of rotation inclined with respect to a rolling axis, a support body on which the guide rolls are mounted and configured to keep the guide rolls constantly in contact with the long metal products, and a support structure configured to support the support body and to which the latter is attached. At least the support structure is made of one or more non-ferrous metal materials with a specific weight less than half the average weight of steel and with heat conductivity equal to or greater than double the average heat conductivity of steel.

Abstract: The present invention relates to a process and to an apparatus for producing a magnesium sheet from a magnesium strip in a rolling device, said process having lower material heat losses compared to known processes and requiring a lower expenditure on apparatus. In the process, the magnesium strip, after preheating, is guided through at least one roll nip formed by at least one pair of counter-rotating working rollers, which comprise a main roller body. The process is characterized in that at least one of the two counter-rotating working rollers comprises at least one heat-insulating sheath surrounding the main roller body.

Abstract: A centrifugally cast composite roll comprising an outer layer made of cast iron having a chemical composition comprising, by mass, 2.7-3.5% of C, 1.5-2.5% of Si, 0.4-1.0% of Mn, 3.7-5.1% of Ni, 0.8-2.2% of Cr, 1.5-4.5% of Mo, 2.0-4.5% of V, and 0.5-2.0% of Nb, the balance being Fe and inevitable impurities, a mass ratio of Nb/V being 0.18-0.65, and a mass ratio of Mo/V being 0.7-2.5, and a structure comprising, by area, 15-45% of a cementite phase and 1-10% of a graphite phase, and an inner layer made of cast iron having excellent mechanical strength and metallurgically bonded to the outer layer; a usable region of the outer layer as deep as 10 mm or more from the surface containing substantially no speck-like-segregated dendrites of bainite and/or martensite having diameters of 1.5 mm or more.

Abstract: A composite rolling mill roll according to the present invention includes: a steel roll shaft; and an outer layer provided around the roll shaft, in which the outer layer includes a sintered body including a base metal which is an iron alloy, a fibrous inclusion which consists of a ceramic and has an average diameter of 1 to 30 ?m and an average aspect ratio of 10 to 500, and a particulate inclusion which consists of a ceramic and has an average diameter of powder 1 to 100 ?m, an amount of the fibrous inclusion is 5 to 40 volume % relative to the volume of the sintered body, and an amount of the particulate inclusion is 5 to 30 volume % relative to the volume of the sintered body.

Abstract: A forged roll for use, inter alia, in the cold rolling industry and a method of producing a forged roll as described. The roll has a steel composition, by weight, with 0.8 to less than 1% C, 0.2 to 0.5% Mn, 0.2 to 2.0% Si, 7.0 to 13.0% Cr, 0.6 to 1.6% Mo, more than 1.0 to 3.0% V, the remainder being Fe and impurities. The steel is tempered martensite with retained austenite at less than 5% per volume with eutectic carbides of less than 5% by volume, a hardness between 780-840 HV, and internal compressive stresses of between ?300 to ?500 MPa.

Abstract: There is provided a roll surface layer material including a roll surface layer with excellent fatigue resistance. The roll surface layer material has a composition including, on a mass % basis, C: 2.3% to 2.9%, Si: 0.2% to 0.8%, Mn: 0.2% to 1.0%, Cr: 5.0% to 7.5%, Mo: 4.4% to 6.5%, V: 5.3% to 7.0%, Nb: 0.6% to 1.5%, and Co: 0.1% to 4.0% so as to satisfy 14.0?(Mo+1.7V)?17.0 (where Mo represents a content (mass %) of Mo and V represents a content (mass %) of V) and further including Al: 0.001% to 0.03% and/or REM: 0.001% to 0.03%, wherein a carbide is contained at an area fraction of 13% to 40%. A composite roll obtained by integrally welding a shaft member to the roll surface layer member is treated as a centrifugal cast roll that includes a surface layer with excellent fatigue resistance.

Abstract: A roll coupled to a separately manufactured axle rotates together with the axle in order to perform a rolling process. The roll includes an inner cylindrical surface, an outer cylindrical surface and both side faces, and at least one key way provided on at least one of the side faces is arranged adjacent to the inner cylindrical surface rather than said outer cylindrical surface, The key way is in a concave curved shape and is a portion of a spherical surface or of an ellipsoidal surface.

Abstract: The rolling mill cast roll having a shield portion made of multi-component white iron with excellent resistance to adhesion and propagation of cracks, having a composition consisting essentially, by weight ratio, of 1.5-2.5% carbon, 3.0-10% chromium, 2.0-8.0% molybdenum, 2.0-8.0% tungsten, 2.0-10% vanadium, 0.1-0.8% sulfur, up to 2.0% manganese, wherein the manganese is balanced with said sulfur in a 2:1 ratio (Mn:S), up to 1.0% silicon, up to 1.0% of nickel, 0.1% Ce, up to 0.08% phosphorus and a sufficient amount of Fe, is produced by a centrifugal casting method.

Abstract: A forged roll for use, inter alia, in the cold rolling industry and a method of producing a forged roll as described. The roll has a steel composition, by weight, with 0.8 to less than 1% C, 0.2 to 0.5% Mn, 0.2 to 2.0% Si, 7.0 to 13.0% Cr, 0.6 to 1.6% Mo, more than 1.0 to 3.0% V, the remainder being Fe and impurities. The steel is tempered martensite with retained austenite at less than 5% per volume with eutectic carbides of less than 5% by volume, a hardness between 780-840 HV, and internal compressive stresses of between ?300 to ?500 MPa.

Abstract: A roll for use in a galvanizing pot, comprising a hollow body brought into contact with a steel strip, and shaft portions connected to the body, at least the body being made of a silicon nitride ceramic having thermal conductivity of 50 W/(m·K) or more at room temperature, and the body having an average surface roughness Ra of 1-20 ?m. The body is preferably shrink-fit to the shaft portions.

Abstract: A method for producing an outer layer for a roll having a structure having MC carbide dispersed at an area ratio of 20-60%, comprising the steps of (1) centrifugally casting a melt having a composition comprising, by mass, 2.2-6.0% of C, 0.1-3.5% of Si, 0.1-3.5% of Mn, and 8-22% of V, the balance being Fe and inevitable impurity elements, to produce a cylindrical body comprising an inner layer having concentration MC carbide, an MC-carbide-poor outer layer, and a concentration gradient layer between the inner layer and the outer layer, in which the area ratio of MC carbide changes, and (2) cutting the cylindrical body to a depth at which the area ratio of MC carbide is 20% or more.

Abstract: The present invention is directed to a rolling mill cast roll with a higher resistance to adhesion and propagation of cracks, and the process for the manufacture thereof, said process comprising the steps of: introduction (1) of waste liquid metal (a), alloy elements (b) and a lot of scrap (c) into a melting furnace; next, melting (2) of the load at about 1,200° C. to 1,500° C.

Abstract: A core is provided with a coating formed by an agglomerate obtained by hardening of a mixture comprising a granulated stone material, preferably of the type having a high hardness factor and light color, and a hardening resin, preferably an epoxy resin, for manufacturing a roller or cylinder of a non-porous external surface, the roller being used for the processing of materials and products. For the manufacture of the roller, a formwork having a cavity for housing a core is prepared so as to provide an interspace which is filled with the mixture, following which compacting of the mixture present in the interspace and then the resin hardening step are performed to obtain a non-porous agglomerate.

Abstract: A roll coupled to a separately manufactured axle rotates together with the axle in order to perform a rolling process. The roll includes an inner cylindrical surface, an outer cylindrical surface and both side faces, and at least one key way provided on at least one of the side faces is arranged adjacent to the inner cylindrical surface rather than said outer cylindrical surface, The key way is in a concave curved shape and is a portion of a spherical surface or of an ellipsoidal surface.

Abstract: The invention relates to a roller comprising an axial support element made of metal and comprising at least two shafts, and a cylindrical shell made of thermostructural composite material. In order to compensate for differential expansion between the metal axial support element and the cylindrical shell made of thermostructural composite material, radial clearance is provided with the axial support element and the cylindrical shell.

Abstract: Improved work roll, particularly for use in closed gap rolling, has a composite structure comprising a cylindrical outer layer (14) made of steel, and providing the work surface of the roll, separated from a steel core (12) by an intermediate layer (13) of material such as aluminium or copper having a lower Young's modules than that of the layer (14). Provided that the dimensions of the outer layer (14) and intermediate layer (13) are chosen appropriately, this combination can release a work roll having an affective Young's modules which is lower than that of steel whilst at the same time retaining the advantages of a steel work surface and enabling higher rolling speeds.

Abstract: A vibration damping roll is provided for rolling contact with a vibrating structure. The vibration damping roll incorporates a wave guide consisting of radially alternating rigid and flexible material having at least two rigid elements disposed adjacent to flexible material and may be provided in the form of a layered structure, a spiral structure, or a plurality of discrete rigid elements disposed in a matrix of flexible material.

Abstract: A roller including an inner tubing and an outer tubing which is fixed relative to the inner tubing by welding the outer tubing to the inner tubing. The roller with weldments is particularly suitably for a nipped application.

Abstract: A process for the production of metal pipes is described in which a thin-walled metal band inclined toward cold spots is gradually formed into a slotted pipe, the longitudinal edges lying flush against one another are welded to one another, and the welded pipe is reduced in its diameter. The forming of the metal band into the slotted pipe is done by opposing metal forming rollers or forming cylinders cooperating pairwise. The forming rollers or forming cylinders guide the metal band to be deformed in its edge area with rolling friction between them. Therein the forming and guiding of the metal band is done with forming rollers and/or forming cylinders and the reduction with rollers whose surface hardness is greater than 100 GPa.

Abstract: When rolling steel sheet and other rolled stock, rattling occurs in certain operating states. This results in reduced quality of the rolled stock and rejects as well as damage to the rolling mill. No improvement was achieved by placing brakes on the cylinders. Electronic monitoring is not a satisfying solution. Given that rattling is a self-starting oscillation, resistance sensors are coupled to the cylinders and/or the rolled stock in order to stabilize the self-starting oscillation modes, modes with negative damping, by means of additional damping. In the example illustrated in FIG. 4, cylinder-shaped, rotating dampers are coupled to the working cylinders. Concentric or disc-shaped layers made of steel and plastic such as those found in layered oscillation absorbers are most effective and adaptable. The arrangement of the working cylinder and the damper illustrated in FIG.

Abstract: The present invention provides a composite roll for cold rolling capable of rolling a cold-rolled steel strip having little edge drop, a cold-rolled stainless steel strip or a bright finish steel strip having excellent surface brightness or a silicon steel strip excellent in magnetic properties without causing breakage of roll, which is a roll in which a sleeve is fitted at a surrounding of a shaft portion with the shaft portion as a central axis and its fabrication method, in which the sleeve is constituted by previously integrating a plurality of pieces of mold members divided by a face intersecting with the central axis of the roll. Further, this is a fit roll in which a sleeve member of an outermost layer is made of WC—Co series hard alloys having Young's modulus of 35000 kgf/mm or more and Co content of 12-50 weight % and is provided with a wall thickness of 3% or more of roll radius and a ratio L/D of a length L of a barrel of the sleeve to a diameter D of the roll falls in a range of 2-10.

Abstract: A combined roll is provided which offers excellent resistance to thermal shock. In this combined roll, an external ring portion is formed of a cemented carbide, and an internal ring portion is formed of a ductile iron metallurgically bonded to the external ring portion by means of casting. The external ring portion is formed of a cemented carbide containing, as binder phase-defining components, Co: 5-27%, Ni: 2-12% and Cr: 0.3-3% and WC as substantially all of the balance and as a hard phase-defining component. The internal ring portion is formed of a ductile iron composed of C: 3 4.5%, Si: 1.5-4.5%, Mn: 0.1-2% and Mg: 0.02-0.2% and, as the balance, Fe and incidental impurities. The internal ring portion may also contain 0.1-5% of one or more of Mo, Cu, Cr, V, W, Sn and Sb. The internal ring portion contains a cored spheroidal graphite structure dispersed in a mixed phase of either perlite, beinite and martensite phases with a ferrite phase.

Abstract: A roll outer layer material for hot rolling includes, as analyzed in weight percent, of 2.5-4.0% C, 6.0-20% Cr, 3.0-10.0% V, 0.6-5.0% Nb, 2.0-15% Mo, 3.0% or below Si, 3.0% or below Mn, C, V, Nb and Cr satisfying a following formula (1),10.5(%).ltoreq.6.5.C(%)-1.3.V(%)-0.7.Nb(%).ltoreq.2.Cr(%)-2(%)(1), and the balance being Fe and incidental impurities. A method of manufacturing a roll for hot rolling includes the steps of centrifugally casting an outer layer material having the above composition, centrifugally casting graphite steel containing 0.5% or above of C as an intermediate layer, and casting an axis material which is a spheroidal graphite cast iron, a flake graphite cast iron or a graphite steel. C is present in the intermediate layer in an amount which satisfies a following formula (2),C (intermediate layer).gtoreq.2.0-0.5 (C-0.2 V-0.

Abstract: An improved caster roll core and shell assembly includes two overlays of stainless steel of different hardness which are deposited on the surface of the roll core, thus prolonging the life of the roll. The method for manufacturing the roll is also described.

Abstract: A roll outer layer material for hot rolling consists essentially, as analyzed in weight percent, of 2.5-4.0% C, 6.0-20% Cr, 3.0-10.0% V, 0.6-5.0% Nb, 2.0-15% Mo, 3.0% or below Si, 3.0% or below Mn, C, V, Nb and Cr satisfying a formula where 10.5.ltoreq.6.5.C(%)--1.3.V(%)--0.7.Nb(%).ltoreq.2.Cr(%)--2, and the balance being Fe and incidental impurities. A method of manufacturing a roll for hot rolling comprises the steps of centrifugally casting an outer layer material having the above composition, centrifugally casting graphite steel containing 0.5% or above of C as an intermediate layer, and casting an axis material which is a spheroidal graphite cast iron, a flake graphite cast iron or a graphite steel. Carbon is present in the intermediate layer in an amount which satisfies a formula, C (intermediate layer).gtoreq.2.0-0.5?C(%)--0.2.V(%)--0.11.Nb(%)! (outer layer).

Abstract: A composite roll for hot rolling wherein the outer layer portion of a composite roll comprises a steel comprised of, in terms of % by weight, 1.5 to 2.4% of C, 3 to 6% of V and 10 to 20% of at least one element selected from the group consisting of Cr, Mo and W and optionally at least one element of 0.05 to 0.20% of Al and 0.02 to 0.10% of Ti as an inoculation material, with the balance comprising Fe and unavoidable impurities, the outer layer portion comprising a metallic structure which has a crystal grain diameter of 30 to 150 .mu.m and is surrounded by a eutectic carbide crystallized in the grain boundary or a metallic structure wherein a primary crystallized carbide is further dispersed and crystallized in a matrix structure of the crystal. It is excellent particularly in the surface roughening resistance.

Abstract: A molten metal plating apparatus includes a roller rotatably supported by a bearing in a molten metal bath, the roller having a shaft sliding portion, the bearing having a sliding portion, both the shaft sliding portion and the sliding portion being made of ceramic sintered body, at least one of both the shaft of the roller and the bearing being made of a ceramic sintered body containing a solid lubricating material. The bearing for the roller, the sleeve and the tip may be formed of a composite body having a ceramic sintered body portion and and a metal portion secured and fitted thereto by an intermediate member which is elastically and plastically deformed at the time of the usage.