4051results about "Rolls" patented technology

A metallic resistive heater and a method of production are described. The resistive heater has a metallic component that is electrically conductive (i.e. has low resistivity) and an oxide, nitride, carbide, and or boride derivative of the metallic component that is electrically insulating (i.e., has high resistivity). The resistivity is controlled by controlling the amount of oxide, nitride, carbide, and boride formation during the deposition of the metallic component and the derivative.

A fuel cell stack module includes a base, a cover dome removably positioned on the base, and a plurality of fuel cell stacks removably positioned on the base below the cover dome. A modular fuel cell system includes a plurality of the fuel cell stack modules, where each fuel cell stack module may be electrically disconnected, removed from the fuel cell system, repaired or serviced without stopping an operation of the other fuel cell stack modules in the fuel cell system.

A roll changing apparatus for a four-high rolling mill comprises rails, provided in a rolling mill stand and on a work side of the rolling mill, for incoming and outgoing of a work roll assembly and a backup roll assembly, and a pusher, provided on a drive side or the work side of the rolling mill, for roll admission and withdrawal for both of work rolls and backup rolls. The roll changing apparatus can be modified into a side shift type roll changing apparatus with ease, at a low cost, and in a short time.

A rolling mill has roughing, intermediate and finishing roll stands on a first side of a billet reheating furnace, and a breakdown mill on an opposite second side of the furnace. Billets are heated to an elevated rolling temperature in the furnace and are then ejected to the second side of the furnace for rolling in the breakdown mill before being directed back through the furnace for continued rolling into finished products at the first side of the furnace in the roughing, intermediate and finishing roll stands.

An article includes a working portion including cemented carbide, and a heat sink portion in thermal communication with the working portion. The heat sink portion includes a heat sink material having a thermal conductivity greater than a thermal conductivity of the cemented carbide. Also disclosed are methods of making an article including a working portion comprising cemented carbide, and a heat sink portion in thermal communication with the working portion and including a heat sink material having a thermal conductivity that is greater than a thermal conductivity of the cemented carbide. The heat sink portion conducts heat from the working portion.

The invention discloses a resource-saving type high-boron high-speed steel composite roll and a manufacturing method of the resource-saving type high-boron high-speed steel composite roll, and belongs to the technical field of rolls. The composite roll is composed of outer-layer high-boron high-speed steel, middle transition-layer graphitic steel and roll core hot rolling medium-carbon round steel, the outer-layer high-boron high-speed steel and the middle transition-layer graphitic steel are formed in a centrifugal combination mode, and the transition-layer graphitic steel and the roll core hot rolling medium-carbon round steel are formed in a hot charging combination mode. The composite roll is high in roll face rigidity and good in rigidity uniformity, and it is guaranteed that the composite roll is excellent in abrasive resistance. A roll core is formed by machining the hot rolling medium-carbon round steel and is good in obdurability, the roll breakage accident cannot happen in the roll using process, and good economic benefits and social benefits are achieved through popularization and application.

The invention relates to high-boron low-alloy high-speed steel roll and a preparation method thereof. The roll comprises two parts, namely a roll barrel (1) and a roll core (2), wherein the roll barrel comprises the following chemical components by weight percent: 0.32-0.55% of C, 1.42-2.13% of B, 5.2-6.5% of Cr, 2.5-4.5% of W, 1.6-1.8% of V, 0.5-1.0% of Nb, 0.3-1.0% of Si, 0.3-1.0% of Mn, 0.10-0.20% of Ti, 0.05-0.12% of N, 0.04-0.12% of Y, 0.08-0.15% of Mg, less than 0.04% of P, less than 0.04% of S and the balance Fe. The roll prepared by the method of the invention is characterized by high hardness, deep quenched depth and good wear resistance and thermal fatigue resistance, and has good use effect in the production of hot rolled steel.

The present invention discloses compound high speed steel roll and its making process. The compound high speed steel roll consists of roll body and roll core compounded through central casting. The roll body is made of high speed steel comprising chemically C 1.8-2.8 (in wt%, same as below), Mo 4.0-8.0, V 3.0-7.0, Nb 1.5-4.0, Cr 6.0-12.0, RE 0.1-0.25, Ti 0.15-0.40, N 0.08-0.20, K 0.06-0.18, Si<2.0, Mn<2.0, S<0.05 and P<0.05, except Fe and inevitable impurity. The roll core is made of high strength nodular cast iron comprising chemically C 3.2-3.6 (in wt%, same as below), Si 1.8-2.4, Mn 0.4-0.8, Ni 0.3-1.2, Cr 0.3-0.8, Mo 0.2-0.5, Mg 0.03-0.08, RE 0.05-0.14, P<0.08 and S<0.03, except Fe and inevitable impurity. The compound high speed steel roll has high wear resistance, simple making process and high production efficiency.

The invention relates to a centrifugal combined indefinite chill cast-iron roller and a preparation method thereof, pertaining to steel rolling technical field. The chemical composition of a roll barrel is (weight percent): 3.2-3.8 C, 3.8-4.5 Ni, 1.2-1.8 Cr, 0.2-0.4 Mo, 0.2-0.5Cu, 1.0-1.8 Si, <0.8Mn, 0.10-0.30 Nb, 0.05-0.20 V, 0.05-0.20 Ti, 0.04-0.07Mg, 0.02-0.05 Y, 0.01-0.03 Sb, and the rest are Fe and unavoidable microimpurity. The invention employs a electric stove to produce a roller, and the roller is moulded with centrifugal casting method; the roller is characterized by high strength and hardness, good toughness, hardness uniformity and hardenability, excellent wear resistance and oxidation resistance and the anti-cold shock and heat shock properties are also good; no phenomena like breaking, peeling, crazing and steel sticking are in the operation process; the service performance is apparently better than high nickel-chrome indefinite chill cast-iron roller; the processing technique is simple, high-heat treatment is not needed and the production cost is low. The invented roll has the advantages that: the rolling mill operating rate is significantly improved, the production cost of mill bar is reduced, the surface quality of the mill bar is improved and the economic and social benefits are good.

The invention relates to a repaired roller and a method for repairing a roller. The method comprises the following steps of: mechanically cutting the waste roller to be repaired along the external surface to remove a worn layer to obtain a roller core, arranging selected cladding material on the surface of the roller core by different addition manners, and irradiating with laser to melt the cladding material together with the surface of the roller to form a cladding layer. The laser cladding layer consists of a cladding surface layer, a cladding intermediate layer and a laser cladding bottom layer and can form gradual functional materials with respective characteristics. The repaired roller has improved mechanical performance, prolonged service life and lowered production cost.

A method, bending machine, and bending equipment line for bending a workpiece involves successively or continuously feeding the workpiece held by a supporting unit from an upstream side of the supporting unit, and performing bending at a downstream side of the supporting unit. The bending method includes: supporting the metal material with a movable roller die; controlling the position of the movable roller die and/or the moving speed of the metal material; heating the metal material in a temperature range in which the heated portion can be plastically deformed and in a temperature range in which quenching can be performed, by using a heating unit that is provided around the outer circumference of the metal material, to apply a bending moment to the heated portion; and rapidly cooling the heated portion, by using a cooling unit that is provided around the outer circumference of the metal material.

The invention relates to a method of producing a strip of nanocrystalline material which is obtained from a wound ribbon that is cast in an amorphous state, having atomic composition [Fe1-a-bCoaNib]100-x-y-2-alpha-beta-gamma Cu<x>Si<y>BzNbalphaM'betaM''gamma, M' being at least one of elements V, Cr, Al and Zn, and M being at least one of elements C, Ge, P, Ga, Sb, In and Be, with: a <= 0.07 and b = 0.1, 0.5 <= x <=1.5 and 2 <= a <= 5, 10 <= y <= 16.9 and 5 <= z <= 8, beta <= 2 and gamma <= 2. According to the invention, the amorphous ribbon is subjected to crystallisation annealing, in which the ribbon undergoes annealing in the unwound state, passing through at least two S-shaped blocks under voltage along an essentially longitudinal axial direction of the ribbon, such that the ribbon is maintained at an annealing temperature of between 530 DEG C and 700 DEG C for between 5 and 120 seconds and under axial tensile stress of between 2 and 1000 Mpa. The tensile stress applied to the amorphous ribbon, the displacement speed of the ribbon during annealing and the annealing time and temperature are all selected such that the cross-section profile of the strip is not in the form of Omega and the maximum deflection of the cross-section of the strip is less than 3% of the width of the strip and preferably less than 1% of the width. The invention also relates to the strip and the core thus obtained and to the device used to implement the method.

The invention discloses a boron-contained centrifugal composite high-speed steel roller, which comprises an outer layer of the high-speed steel roller, a middle layer of the high-speed steel roller and a core of the high-speed steel roller. The manufacturing method includes steps of smelting, interrupted front treatment, roller pouring, annealing, rough machining, double tempering, finish machining and testing. By the method, three-layer composite roller technology is adopted in the boron-contained centrifugal composite high-speed steel roller, composite ability of the outer layer of the high-speed steel roller and the core of the high-speed steel roller is increased, the roller is less prone to spalling, high in rigidity and accident resistant ability, fine in abrasion resistance, safe in use, low in energy consumption and short in cycle in heat treatment, oxidation and decarburization of the roller and roller breakage in use are avoided. The manufacturing method is simple and hot quenching process is omitted.

A manufacturing method for centrifugally casting high-boron high-speed steel composite roller belongs to the technical field of rolled steel. The invention aims to provide the manufacturing method for centrifugally casting the high boron high-speed steel composite roller without element segregation. The manufacturing method comprises the following steps: injecting high-seed steel liquid into a metal casting mould rotating at high speed on a centrifugal machine after the high-seed steel liquid is cooled by an inclined cooling plate; spaying, cooling and casting the high-seed steel liquid during a pouring process; and then centrifugally pouring an intermediate layer; finally pouring cast steel or alloyed ductile cast iron in a rolling core in a static state; and then obtaining the high-boron high-speed steel composite roller. The high-boron high-speed steel composite roller has the advantages of fine tissues on an external layer, compactness and no element segregation; and a boron element on the external layer cannot be mixed into a rolling core.

A technology for rolling the composite Cu-Al plate includes such steps as preheating the copper band and aluminium plate respectively at different temp for different time, acid washing of copper band, alkali washing of aluminium plate, brushing surface by steel wire brush, rolling by a pair of upper concave roller and lower convex roller, annealing in inertial gas, and straightening.

The invention discloses a polyvalent microalloying high-chromium cast-iron and usage of rare earth, which comprises the following parts: 1.0-3.5% carbon, 8.0-26.0% chromium, 0.5-4.5% nickel, 0.15-2.0% molybdenum, 0.5-2.0% copper, 0.05-2.0% aluminium, 0.03-0.3% vanadium, 0.005-0.20% rare earth, not more than 0.5% silicon, not more than 0.7% manganese, not more than 0.05% phosphor and ferric.

The invention relates to a high-speed steel roll and a preparation method thereof by centrifugal compounding in an electromagnetic field, belonging to the technical field of preparation of the high-speed steel roll. The components of a working layer material of the high-speed steel roll are as follows (in weight percent): 1.5 to 2.5 percent of C, 4.0 to 6.0 percent of V, 4.0 to 6.0 percent of W, 1.5 to 4.5 percent of Mo, 2.0 to 4.0 percent of Cr, 0.04 to 0.18 percent of Zr, 0.001 to 0.003 percent of B, less than or equal to 0.5 percent of Si, less than or equal to 0.5 percent of Mn, and the balance of Fe and impurity elements; and in the impurity elements, the required contents of S, P and O are respectively less than 0.01 percent, less than 0.01 percent and less than 0.0010 percent. The roll is cast by adopting a centrifugal compounding method in a pulse electromagnetic field, the frequency of the pulse magnetic field is 0.1 to 10Hz, and the peak strength of a central magnetic field of a cast mold is 1 to 10T. The roll has a plurality of precipitation strengthening phases, and the applied pulse magnetic field leads the strengthening phases and matrix crystal grains to be refined effectively and leads the strengthening phases to be distributed in a dispersed manner, thus overcoming the segregation of alloy elements and greatly improving the performance of the roll.

The invention discloses cold work roll steel for high-strength steel rolling, a cold work roll and its manufacturing method. The material of cold work roll is composed of the following chemical components of: by weight, 0.6-0.8% of C; 0.6-1.5% of Si; 0.6-1.5% of Mn; 4.0-6.0% of Cr; 0.5-2.0% of Mo; 0.5-1.0% of V; P being less than or equal to 0.020%; S being less than or equal to 0.015%; and the balance being Fe and unavoidable impurities. The manufacturing process comprises steps of: electric furnace smelting; secondary refining; vacuum degasification; electric bar casting; electroslag refining; ingot casting; forging; preheat treatment; rough machining; quenching and tempering treatment; semi-finish machining; final heat treatment; finish machining; and finished product. According to thenovel cold work roll provided by the invention, the ratio of the alloy elements is optimized based on 5% of Cr. By the adoption of a short-time high-temperature solid solution quenched-tempered heat treatment technology, the roll strength and wear resistance of the cold work roll are improved, thus satisfying production requirements of high-strength cold rolled strips.