Patent application number | Description | Published |
20090101240 | CARBONITRIDING METHOD, MACHINERY COMPONENT FABRICATION METHOD, AND MACHINERY COMPONENT - A carbonitriding method that can improve the nitrogen permeating rate to render the carbonitriding process effective is directed to carbonitriding a workpiece formed of steel that contains at least 0.8 mass % of carbon by heating in an atmosphere including ammonia, carbon monoxide, carbon dioxide and hydrogen. The method includes an atmosphere control step ( | 04-23-2009 |
20090165896 | Carbonitriding Method, Machinery Component Fabrication Method, and Machinery Component - A carbonitriding method that allows the permeating rate of nitrogen to be increased to improve the efficiency of the carbonitriding process is directed to carbonitriding a workpiece formed of steel containing at least 0.8 mass % of carbon, including an atmosphere control step of controlling the atmosphere in a heat treatment furnace, and a heating pattern control step of controlling the temperature history applied to a workpiece. The atmosphere control step includes an undecomposed ammonia concentration control step of controlling the undecomposed ammonia concentration in the heat treatment furnace, and a partial pressure control step of controlling the partial pressure of at least one of carbon monoxide and carbon dioxide in the heat treatment furnace. In the atmosphere control step, the undecomposed ammonia concentration control step and partial pressure control step are carried out such that the γ value defined by γ=a | 07-02-2009 |
20090260721 | METHOD OF RESTRAINED-QUENCHING OF ANNULAR MEMBER - A method of restrained-quenching of an annular member, that can readily ensure a sufficient effect of restraint, increase treatment efficiency of a quench hardening treatment, and suppress production cost of the annular member, includes a heating step, a first cooling step, a restraint step, and a second cooling step. In the heating step, a bearing ring formed as the annular member is heated to a temperature not lower than an A | 10-22-2009 |
20100154937 | CARBONITRIDING METHOD, MACHINERY COMPONENT FABRICATION METHOD, AND MACHINERY COMPONENT - A carbonitriding method that can improve the nitrogen permeating rate to render the carbonitriding process effective includes an atmosphere control step ( | 06-24-2010 |
20100213648 | HEAT TREATMENT FURNACE - A heat treatment furnace that allows the atmosphere in the heat treatment furnace to be controlled with favorable accuracy includes a second heating zone identified as a reaction chamber, having a floor belt to hold a workpiece, and an atmosphere collect pipe having an opening in the second heating zone to collect an atmosphere in the second heating zone through the opening. The atmosphere collect pipe is installed to allow the distance between the opening and the floor belt to be modified. | 08-26-2010 |
20100239205 | MECHANICAL COMPONENT AND ROLLING BEARING - An outer ring, an inner ring and a ball serving as mechanical components configuring a deep groove ball bearing are formed of steel containing at least 0.77 mass % and not more than 0.85 mass % of carbon, at least 0.01 mass % and not more than 0.25 mass % of silicon, at least 0.01 mass % and not more than 0.35 mass % of manganese, at least 0.01 mass % and not more than 0.15 mass % of nickel, at least 3.75 mass % and not more than 4.25 mass % of chromium, at least 4 mass % and not more than 4.5 mass % of molybdenum and at least 0.9 mass % and not more than 1.1 mass % of vanadium with a remainder consisting of iron and impurity, and have raceway/rolling contact surfaces, the surface being included in a region having a nitrogen enriched layer having a nitrogen concentration of at least 0.05 mass %, the nitrogen enriched layer having a carbon concentration and the nitrogen concentration, in total, of at least 0.82 mass % and not more than 1.9 mass %. | 09-23-2010 |
20120121420 | METHOD FOR HEAT-TREATING A RING-SHAPED MEMBER, METHOD FOR PRODUCING A RING-SHAPED MEMBER, RING-SHAPED MEMBER, BEARING RING, ROLLING BEARING, AND METHOD FOR PRODUCING A BEARING RING - Disclosed is a method for heat-treating a ring-shaped member, which makes it possible to form a quench-hardened region having a uniform annular shape in the circumferential direction, while the production costs in terms of the quenching apparatus are kept down. The method includes the following steps: a step in which a coil which is disposed in such a way as to face a rolling contact surface of a ring-shaped formed body made of steel and which performs induction heating of the formed body is rotated relative to the formed body in the circumferential direction thereof, whereby an annular heating region which is heated to a temperature at or above an A | 05-17-2012 |
Patent application number | Description | Published |
20090245706 | ROLLING BEARING - An outer ring and an inner ring of a rolling bearing are constituted of steel containing 0.77 to 0.85% of carbon, 0.01 to 0.25% of silicon, 0.01 to 0.35% of manganese, 0.01 to 0.15% of nickel, 3.75 to 4.25% of chromium, 4 to 4.5% of molybdenum and 0.9 to 1.1% of vanadium with the rest consisting of iron and impurities, a nitrogen-enriched layer having a nitrogen concentration of at least 0.05 mass % is formed on a region including a rolling surface, and the total of a carbon concentration and the nitrogen concentration in the nitrogen-enriched layer is at least 0.82 mass % and not more than 1.9 mass %. A DLC coating layer is arranged on a region including an outer ring contact surface. | 10-01-2009 |
20100232735 | BEARING FOR ALTERNATOR AND BEARING FOR PULLEY - A bearing for alternators and a bearing for pulleys for reducing hydrogen embrittlement or cracking is used when the bearing is in an environment having a severe condition, such as, when hydrogen is generated from grease or the like. The bearing includes a rolling element, an inner ring and an outer ring, and at least one of the rolling element, where the inner and outer rings have a nitrogen enriched layer containing austenite crystal grains having a grain size number exceeding 10. | 09-16-2010 |
20120014635 | MECHANICAL COMPONENT AND ROLLING BEARING - An outer ring, an inner ring and a ball serving as mechanical components configuring a deep groove ball bearing are formed of steel containing at least 0.77 mass % and not more than 0.85 mass % of carbon, at least 0.01 mass % and not more than 0.25 mass % of silicon, at least 0.01 mass % and not more than 0.35 mass % of manganese, at least 0.01 mass % and not more than 0.15 mass % of nickel, at least 3.75 mass % and not more than 4.25 mass % of chromium, at least 4 mass % and not more than 4.5 mass % of molybdenum and at least 0.9 mass % and not more than 1.1 mass % of vanadium with a remainder consisting of iron and impurity, and have raceway/rolling contact surfaces, the surface being included in a region having a nitrogen enriched layer having a nitrogen concentration of at least 0.05 mass %, the nitrogen enriched layer having a carbon concentration and the nitrogen concentration, in total, of at least 0.82 mass % and not more than 1.9 mass %. | 01-19-2012 |
20120234008 | GAS SUPPLY DEVICE AND EXHAUST GAS POWER GENERATION SYSTEM - A gas supply device includes a first flow channel connecting a heat-treating furnace and a power generation device, a pressure control valve arranged in the first flow channel for controlling a pressure of exhaust gas flowing through the first flow channel, and a furnace pressure gauge measuring a pressure within the heat-treating furnace. If the pressure within the heat-treating furnace measured by the furnace pressure gauge becomes lower than a predetermined value, the pressure control valve controls the pressure of the exhaust gas to increase the pressure of the exhaust gas within the first flow channel. | 09-20-2012 |
20130019666 | BEARING PART, BEARING, AND METHOD FOR INSPECTING BEARING PART - An inspection method which quantitatively and simply assures a nitrogen concentration in a carbonitriding-treated bearing part, and a bearing part and a bearing for which a nitrogen concentration is quantitatively assured are obtained. An inner race, an outer race, and balls as bearing parts are each a bearing part made of JIS standard SUJ2 and having a carbon nitrided layer formed in a surface thereof, wherein, after heat treatment at a heating temperature of 500° C. for a retention time of one hour is performed, a Vickers hardness at a position with a depth of 30 μm from the surface is higher than a Vickers hardness at a core portion, which is a region where the carbonitrided layer is not formed in a thickness direction of the bearing part, by not less than 130 HV. | 01-24-2013 |
20130077906 | BEARING FOR ALTERNATOR AND BEARING FOR PULLEY - There is provided a bearing for alternators and a bearing for pulleys capable of reducing hydrogen embrittlement or cracking despite that the bearing is used in an environment under such a severe condition that hydrogen is generated from grease or the like and the bearing experiences a load of a condition facilitating hydrogen embrittlement or cracking. The bearing includes a rolling element, an inner ring and an outer ring, and at least one of the rolling element and the inner and outer rings has a nitrogen enriched layer and contains austenite crystal grains having a grain size number exceeding 10. | 03-28-2013 |
20130301969 | METHOD FOR PRODUCING BEARING RING, BEARING RING, AND ROLLING BEARING - A method for producing a bearing ring of a rolling bearing includes the steps of: preparing a formed body constituted of hypereutectoid steel; forming an annular heated region heated to a temperature of at least an A | 11-14-2013 |
20140041763 | GAS NITROCARBURIZING METHOD AND METHOD FOR MANUFACTURING BEARING PART - Provided is a gas nitrocarburizing method forming a nitride layer in a surface layer portion of a workpiece made of steel by heating the workpiece within a heat treatment furnace into which a heat treatment gas is introduced, the heat treatment gas containing ammonia gas and at least one of carbon dioxide gas and hydrogen gas, and having a remainder formed of an impurity. | 02-13-2014 |
20140305552 | METHOD FOR HEAT-TREATING RING-SHAPED MEMBER AND METHOD FOR PRODUCING RING-SHAPED MEMBER - A method for heat-treating a ring-shaped member includes the steps of: forming, by relatively rotating an coil along the circumferential direction of the formed body, an annular heated region in the formed body, the heated region having the steel austenitized therein; and simultaneously cooling a whole of the heated region to a temperature of not more than an M | 10-16-2014 |
20140321789 | MACHINE PART, ROLLING BEARING, TAPERED ROLLER BEARING, AND METHOD FOR MANUFACTURING MACHINE PART - An outer ring, an inner ring and a ball are each constituted of steel containing at least 0.60 mass % and not more than 1.50 mass % of carbon, at least 0.15 mass % and not more than 2.50 mass % of silicon, at least 0.30 mass % and not more than 1.50 mass % of manganese, and at least 0.20 mass % and not more than 2.00 mass % of chromium with the rest consisting of an impurity. A nitrogen concentration in surface layer portions is at least 0.3 mass %. An average quantity of residual austenite as a whole in each of the outer ring, the inner ring and the ball is not more than 20 volume %. | 10-30-2014 |
20140348454 | BEARING PART, ROLLING BEARING, AND METHODS OF MANUFACTURING THEM - An outer ring, an inner ring, and a ball, each of which is a bearing part, are made of a quench-hardened steel containing not less than 0.90 mass % and not more than 1.05 mass % of carbon, not less than 0.15 mass % and not more than 0.35 mass % of silicon, not less than 0.01 mass % and not more than 0.50 mass % of manganese, and not less than 1.30 mass % and not more than 1.65 mass % of chromium with the rest consisting of an impurity. A contact surface thereof with another part has a nitrogen concentration of not less than 0.25 mass %. A remaining austenite amount in the contact surface is not less than 6 volume % and not more than 12 volume %. | 11-27-2014 |