Abstract: An extruded heat transfer tube with an internal passage includes a tube body made of an extruded material of an aluminum alloy having a composition that includes 0.3 mass % or more and less than 0.8 mass % of Mn; more than 0.1 mass % and less than 0.32 mass % of Si; 0.3 mass % or less of Fe; 0.06 mass % or more and 0.3 mass % or less of Ti; and Al balance including inevitable impurities, a ratio of a Mn content to a Si content, Mn %/Si %, exceeding 2.5. The extruded heat transfer tube further includes a Zn-containing layer provided directly on an outer surface of the tube body.

Abstract: An aluminum alloy fin material has a composition, in % by mass, of the following: Zr: 0.05 to 0.25%, Mn: 1.3 to 1.8%, Si: 0.7 to 1.3%, Fe: 0.10 to 0.35%, and Zn: 1.2 to 3.0%, the remainder being Al and inevitable impurities. The aluminum alloy fin material has a solidus temperature of 615° C. or higher, a tensile strength after brazing of 135 MPa or higher, a pitting potential after brazing in the range of ?900 to ?780 mV, and an average crystal grain diameter in a rolled surface after brazing in the range of 200 ?m to 1,000 ?m.

Abstract: A method in accordance with the present application includes sending a raw tube from a drum to an unwinding side capstan while the raw tube is rotated around a central axis perpendicular to a winding shaft of the drum by rotating the drum and the unwinding side capstan about the central axis concurrently with unwinding of the raw tube from the drum holding the raw tube, on an inner surface of which multiple straight grooves along a longitudinal direction of the raw tube are formed with an interval in a circumferential direction, in a coil shape, to wind the raw tube around the unwinding side capstan, and drawing in which the unwound raw tube is drawn while the diameter of the raw tube is reduced, and then the raw tube is wound around the drawing side capstan to twist the raw tube and obtain an inner spiral grooved tube.

Abstract: An aluminum alloy brazing sheet has high strength, corrosion resistance and elongation, and includes an aluminum alloy clad material. The material includes a core material, one surface of which is clad with a sacrificial material and an other surface of which is clad with an Al—Si-based or Al—Si—Zn-based brazing filler metal. The core material has a composition containing 1.3 to 2.0% Mn, 0.6 to 1.3% Si, 0.1 to 0.5% Fe and 0.7 to 1.3% Cu, by mass, with the balance Al and impurities. The sacrificial material has a composition containing more than 4.0% to 8.0% Zn, 0.7 to 2.0% Mn, 0.3 to 1.0% Si, 0.3 to 1.0% Fe and 0.05 to 0.3% Ti, by mass, with the balance Al and impurities. At least the core material has a lamellar crystal grain structure. Elongation of material is at least 4% and a tensile strength after brazing is at least 170 MPa.

Abstract: A method in accordance with the present application includes sending a raw tube from a drum to an unwinding side capstan while the raw tube is rotated around a central axis perpendicular to a winding shaft of the drum by rotating the drum and the unwinding side capstan about the central axis concurrently with unwinding of the raw tube from the drum holding the raw tube, on an inner surface of which multiple straight grooves along a longitudinal direction of the raw tube are formed with an interval in a circumferential direction, in a coil shape, to wind the raw tube around the unwinding side capstan, and drawing in which the unwound raw tube is drawn while the diameter of the raw tube is reduced, and then the raw tube is wound around the drawing side capstan to twist the raw tube and obtain an inner spiral grooved tube.

Abstract: A method of controlling a hydraulic system, the hydraulic system including a ram cylinder unit having a cylinder and a ram, and a hydraulic pump and a reservoir used to supply hydraulic fluid to the cylinder, and hydraulically driving the ram using the hydraulic fluid so as to move against a specific load, the method includes determining what a present state is one of an initial state, a proportional steady state, and a later state, controlling the pumping rate, which is obtained by adding the flow rate corresponding to the volume loss due to the compression of the hydraulic fluid thereto, to control the ram in the initial state, and controlling the pumping rate, which is obtained by subtracting the flow rate corresponding to volume recovery of the hydraulic fluid due to the relief of compression of the hydraulic fluid therefrom, to control the ram in the later state.

Abstract: An aluminum alloy fin material for a heat exchanger in the present invention comprises an aluminum alloy having a composition containing Mn: 1.2 to 2.0%, Cu: 0.05 to 0.20%, Si: 0.5 to 1.30%, Fe: 0.05 to 0.5%, and Zn: 1.0 to 3.0% by mass and a remainder comprising Al and an unavoidable impurity, further containing one or two or more of Ti: 0.01 to 0.20%, Cr: 0.01 to 0.20% and Mg: 0.01 to 0.20% by mass as desired, and, after heating in brazing, has a tensile strength of 140 MPa or more, a proof stress of 50 MPa or more, an electrical conductivity of 42% IACS or more, an average grain diameter of 150 ?m or more and less than 700 ?m, and a potential of ?800 mV or more and ?720 mV or less.

Abstract: An aluminum alloy heat exchanger with aluminum alloy tubes is provided by assembling and brazing. A coating which includes from 1 to 5 g/m2 of Si powder, from 3 to 20 g/m2 of Zn containing flux, and from 0.2 to 8.3 g/m2 of binder is formed on the aluminum alloy tubes. The fins contain Zn and 0.8 to 2.0% by mass of Mn, Si in a ratio of 1/2.5 to 1/3.5 relative to the Mn, and less than 0.30% by mass of Fe. A fillet is formed between the tube and the aluminum alloy fin after brazing, and a primary crystal portion is formed in the fillet. A eutectic crystal portion is formed in a portion other than the primary crystal portion, and the electric potential of the primary crystal portion is equal to or higher than the electric potential of the aluminum alloy fin.

Abstract: A heat exchanger tube precursor that allows manufacturing a heat exchanger having high corrosion resistance after brazing treatment is provided. The heat exchanger tube precursor includes: an Al alloy tube; and a flux layer including a Si powder, a Zn-containing flux, a Zn-free flux, and a binder, the flux layer being formed on an outer surface of the Al alloy tube.

Abstract: A heat exchanger tube precursor that allows manufacturing a heat exchanger having high corrosion resistance after brazing treatment is provided. The heat exchanger tube precursor includes: an Al alloy tube; and a flux layer including a Si powder, a Zn-containing flux, a Zn-free flux, and a binder, the flux layer being formed on an outer surface of the Al alloy tube.

Abstract: In order to enable a satisfactory fluxless brazing without needing flux or vacuum facilities, a brazing object including an aluminum alloy material provided with an Al—Si—Mg brazing filler metal is joined by the Al—Si—Mg brazing filler metal without the use of flux by heating the aluminum alloy material, when raising the temperature in a brazing furnace, at least in a temperature range of 450° C. to before melting of the filler metal under a first inert gas atmosphere having an oxygen concentration of preferably 50 ppm and following by heating at least at or above a temperature at which the filler metal starts to melt under a second inert gas atmosphere having an oxygen concentration of preferably 25 ppm and a nitrogen gas concentration of preferably 10% by volume or less.

Abstract: An aluminum alloy heat exchanger with aluminum alloy tubes is provided by assembling and brazing. A coating which includes from 1 to 5 g/m2 of Si powder, from 3 to 20 g/m2 of Zn containing flux, and from 0.2 to 8.3 g/m2 of binder is formed on the aluminum alloy tubes. The fins contain Zn and 0.8 to 2.0% by mass of Mn, Si in a ratio of 1/2.5 to 1/3.5 relative to the Mn, and less than 0.30% by mass of Fe. A fillet is formed between the tube and the aluminum alloy fin after brazing, and a primary crystal portion is formed in the fillet. A eutectic crystal portion is formed in a portion other than the primary crystal portion, and the electric potential of the primary crystal portion is equal to or higher than the electric potential of the aluminum alloy fin.

Abstract: A heat transfer tube includes: a tube body made of an extruded material of an aluminum alloy having a composition including: 0.3 mass % or more and less than 0.8 mass % of Mn; more than 0.1 mass % and less than 0.32 mass % of Si; 0.3 mass % or less of Fe; 0.06 mass % or more and 0.3 mass % or less of Ti; and Al balance including inevitable impurities, a ratio of a Mn content to a Si content, Mn %/Si %, exceeding 2.5; and a Zn-containing layer provided to an outer surface of the tube body.

Abstract: An aluminum alloy heat exchanger with aluminum alloy tubes is provided by assembling and brazing. A coating which includes from 1 to 5 g/m2 of Si powder, from 3 to 20 g/m2 of Zn containing flux, and from 0.2 to 8.3 g/m2 of binder is formed on the aluminum alloy tubes. The fins contain Zn and 0.8 to 2.0% by mass of Mn, Si in a ratio of 1/2.5 to 1/3.5 relative to the Mn, and less than 0.30% by mass of Fe. A fillet is formed between the tube and the aluminum alloy fin after brazing, and a primary crystal portion is formed in the fillet. A eutectic crystal portion is formed in a portion other than the primary crystal portion, and the electric potential of the primary crystal portion is equal to or higher than the electric potential of the aluminum alloy fin.

Abstract: In order to enable a satisfactory fluxless brazing without needing flux or vacuum facilities, a brazing object including an aluminum alloy material provided with an Al—Si—Mg brazing filler metal is joined by the Al—Si—Mg brazing filler metal without the use of flux by heating the aluminum alloy material, when raising the temperature in a brazing furnace, at least in a temperature range of 450° C. to before melting of the filler metal under a first inert gas atmosphere having an oxygen concentration of preferably 50 ppm and following by heating at least at or above a temperature at which the filler metal starts to melt under a second inert gas atmosphere having an oxygen concentration of preferably 25 ppm and a nitrogen gas concentration of preferably 10% by volume or less.

Abstract: An extrusion die device includes a die holder including a supporting hole and a die assembly accommodated in the supporting hole, wherein the die assembly includes a male die including a core member having a projected portion, a core case holding the core member, a female die including a body which includes an engagement groove engaging the core case of the male die, and which engages the supporting hole, and a nesting member formed in an annular shape and accommodated in the body at a portion close to a raw material supply part, and a cap member formed in a plate shape, disposed at a position closer to the raw material supply part than from the male die, covering a portion of the core member, and connected to the core case, and wherein a space between the nesting member and the core member is defined as a molding hole allowing the extrusion raw material to pass therethrough.

Abstract: A heat exchanger tube precursor that allows manufacturing a heat exchanger having high corrosion resistance after brazing treatment is provided. The heat exchanger tube precursor includes: an Al alloy tube; and a flux layer including a Si powder, a Zn-containing flux, a Zn-free flux, and a binder, the flux layer being formed on an outer surface of the Al alloy tube.

Abstract: A heat exchanger tube comprising an Al alloy extruded tube, and a flux layer including Si powder, Zn-containing flux, and binder formed on an outer surface of the Al alloy extruded tube, wherein an amount of the Si powder applied on the Al alloy extruded tube is in a range of 1 g/m2 or more and 5 g/m2 or less, an amount of the Zn containing flux applied on the Al alloy extruded tube is in a range of 3 g/m2 or more and 20 g/m2 or less, and the Si powder has a particle diameter distribution such that 99% particle diameter is 5 ?m or more and 20 ?m or less, and an amount of coarse particle having a diameter of not smaller than 5 times (D99) is less than 1 ppm by volume.

Abstract: A method of controlling a hydraulic system, the hydraulic system including a ram cylinder unit having a cylinder and a ram, and a hydraulic pump and a reservoir used to supply hydraulic fluid to the cylinder, and hydraulically driving the ram using the hydraulic fluid so as to move against a specific load, the method includes determining what a present state is one of an initial state, a proportional steady state, and a later state, controlling the pumping rate, which is obtained by adding the flow rate corresponding to the volume loss due to the compression of the hydraulic fluid thereto, to control the ram in the initial state, and controlling the pumping rate, which is obtained by subtracting the flow rate corresponding to volume recovery of the hydraulic fluid due to the relief of compression of the hydraulic fluid therefrom, to control the ram in the later state.

Abstract: An extrusion die device includes a die holder including a supporting hole and a die assembly accommodated in the supporting hole, wherein the die assembly includes a male die including a core member having a projected portion, a core case holding the core member, a female die including a body which includes an engagement groove engaging the core case of the male die, and which engages the supporting hole, and a nesting member formed in an annular shape and accommodated in the body at a portion close to a raw material supply part, and a cap member formed in a plate shape, disposed at a position closer to the raw material supply part than from the male die, covering a portion of the core member, and connected to the core case, and wherein a space between the nesting member and the core member is defined as a molding hole allowing the extrusion raw material to pass therethrough.