Patent application number | Description | Published |
20090314049 | METHOD FOR PRODUCING PEARLITIC RAIL EXCELLENT IN WEAR RESISTANCE AND DUCTILITY - The invention provides a method for producing a pearlitic rail by subjecting to at least rough hot rolling and finish hot rolling a billet comprising, in mass %, C: 0.65-1.20%, Si: 0.05-2.00%, Mn: 0.05-2.00%, and a remainder of iron an unavoidable impurities, wherein the finish hot rolling is conducted by rolling at a rail head surface temperature in a range of not higher than 900° C. to not lower than Ar | 12-24-2009 |
20110155821 | PEARLITE RAIL HAVING SUPERIOR ABRASION RESISTANCE AND EXCELLENT TOUGHNESS - This pearlite rail consists of a steel including: in terms of percent by mass, C: 0.65 to 1.20%; Si: 0.05 to 2.00%; Mn: 0.05 to 2.00%; P≦0.0150%; S≦0.0100%; Ca: 0.0005 to 0.0200%, and Fe and inevitable impurities as the balance, wherein a head surface portion which ranges from surfaces of head corner portions and a head top portion to a depth of 10 mm has a pearlite structure, a hardness Hv of the pearlite structure is in a range of 320 to 500, and Mn sulfide-based inclusions having major lengths in a range of 10 to 100 μm are present at an amount per unit area in a range of 10 to 200/mm | 06-30-2011 |
20110211900 | IMAGE FORMING APPARATUS AND CUTTING DEVICE - An image forming apparatus includes a first conveying unit provided downstream an image forming unit; a second conveying unit provided downstream the first conveying unit; a first cutting unit provided downstream the second conveying unit; and a second cutting unit provided downstream the first cutting unit. One of the first and second cutting units cuts an upstream end of an image on the continuous sheet, the other cuts a downstream end of the same image. The second conveying unit is stopped during the cutting by the first cutting unit to form a loop of the continuous sheet, and then if the cutting is ended, the second conveying unit conveys the continuous sheet at a higher conveyance speed than a conveyance speed by the first conveying unit to reduce the loop. | 09-01-2011 |
20110226389 | PEARLITE RAIL - A pearlite rail contains, by mass %, 0.65 to 1.20% of C; 0.05 to 2.00% of Si; 0.05 to 2.00% of Mn; and the balance composed of Fe and inevitable impurities, wherein at least part of the head portion and at least part of the bottom portion has a pearlite structure, and the surface hardness of a portion of the pearlite structure is in a range of Hv320 to Hv500 and a maximum surface roughness of a portion of the pearlite structure is less than or equal to 180 μm. | 09-22-2011 |
20110273510 | PRINTING APPARATUS - A plurality of recording head units are supported by a holder in an integrated manner. The recording head units and pairs of rollers which hold a sheet are arranged alternately along a sheet conveying direction. An elastic member is disposed in a clearance between the holder and each of the recording head units supported by the holder in an elastically deformed manner to form an airtight seal. The airtight seal prevents upward leakage, from the clearance, of the humidifying gas introduced into the narrow space to which ink nozzles of the recording head units are exposed. | 11-10-2011 |
20110279541 | RECORDING APPARATUS - A holder that holds a line recording head is displaced in a sheet width direction against the urging force of an elastic portion to bring an abutment portion of the holder into contact with one of a plurality of positioning surfaces provided at a reference portion of a sheet conveying mechanism. The holder is positioned and fixed to the reference portion, with the urging force exerted thereto. | 11-17-2011 |
20110303756 | PEARLITIC RAIL WITH EXCELLENT WEAR RESISTANCE AND TOUGHNESS - This pearlitic rail consists of a steel including: in terms of percent by mass, C: 0.65% to 1.20%; Si: 0.05% to 2.00%; Mn: 0.05% to 2.00%; and REM: 0.0005% to 0.0500%, with the balance being Fe and inevitable impurities, wherein, in a head portion of the rail, a head surface portion which ranges from surfaces of head corner portions and a head top portion to a depth of 10 mm has a pearlite structure, and the hardness Hv of the head surface portion is in a range of 320 to 500. | 12-15-2011 |
20120015212 | METHOD OF COOLING RAIL WELD ZONE, DEVICE FOR COOLING RAIL WELD ZONE, AND RAIL WELD JOINT - The invention provides a method of cooling a rail weld zone. The method includes a first rail web portion cooling process of cooling a rail web portion cooling region of the rail weld zone in a part of a temperature range until the completion of transformation from austenite to pearlite, a second rail web portion cooling process of cooling the rail web portion cooling region after the entire rail web portion of the rail weld zone is transformed to pearlite, a foot portion cooling process of cooling a foot portion of the rail weld zone, and a head portion cooling process of cooling a head portion of the rail weld zone. When cooling time of the first and second rail web portion cooling processes is t minute, a k value satisfies an expression represented as −0.1t+0.63≦k≦−0.1t+2.33. | 01-19-2012 |
20120087825 | Pearlite-Based High Carbon Steel Rail Having Excellent Ductility And Process For Production Thereof - This high-carbon pearlitic steel rail having excellent ductility, includes: in terms of percent by mass, C: more than 0.85% to 1.40%; Si: 0.10% to 2.00%; Mn: 0.10% to 2.00%; Ti: 0.001% to 0.01%; V: 0.005% to 0.20%; and N: less than 0.0040%, with the balance being Fe and inevitable impurities, wherein contents of Ti and V fulfill the following formula (1), and a rail head portion has a pearlite structure. | 04-12-2012 |
20130065079 | STEEL RAIL AND METHOD OF MANUFACTURING THE SAME - A steel rail includes: by mass %, higher than 0.85% to 1.20% of C; 0.05% to 2.00% of Si; 0.05% to 0.50% of Mn; 0.05% to 0.60% of Cr; P≦0.0150%; and the balance consisting of Fe and inevitable impurities, wherein 97% or more of a head surface portion which is in a range from a surface of a head corner portion and a head top portion as a starting point to a depth of 10 mm has a pearlite structure, a Vickers hardness of the pearlite structure is Hv320 to 500, and a CMn/FMn value which is a value obtained by dividing CMn [at. %] that is a Mn concentration of a cementite phase in the pearlite structure by FMn [at. %] that is a Mn concentration of a ferrite phase is equal to or higher than 1.0 and equal to or less than 5.0. | 03-14-2013 |
20140087320 | METHOD OF REHEATING RAIL WELD ZONE - A method of reheating a rail weld zone after rails were welded, a distance C between a reheating region P of a rail web portion | 03-27-2014 |
20150069141 | RAIL - In the rail, 95% or more of a structure in a head surface section, which is a range from surfaces of head corner sections and a head top section of the rail as a starting point to a depth of 20 mm, is a pearlite or bainite structure and the structure contains 20 to 200 MnS-based sulfides formed around an Al-based oxide as a nucleus and having a grain size in a range of 1 μm to 10 μm per square millimeter of an area to be inspected on a horizontal cross section of the rail. | 03-12-2015 |