Jfe Steel Corporation

Nec Network and Sensor Systems, Ltd.

Naoki Iizuka

Minoru Honjo

Shigeo Okamoto

Ryo Matsuoka

Yukihira Nakazato

Proposed are the welding conditions under which welds are always stably formed such that the difference in hardness between flash-butt welds and rail base metal and the deflection in a bending test are in better ranges. A plurality of pieces of rail base metal are joined via welds formed by flash-butt welding, where the rail base metal has a chemical composition containing C: 0.60 to 1.20 mass %, Si: 0.10 to 1.50 mass %, Mn: 0.10 to 1.50 mass %, and Cr: 0.10 to 1.50 mass %, with the balance being Fe and inevitable impurities, and the flash-butt welding is performed with an amount of welding heat input of 1.50×10kA×sec or more and 4.50×10kA×sec or less.

Method for manufacturing rail, and rail

In order to suppress the amount of time needed for the start-up of a microwave tube carried out when voltage fed from a power source has decreased, while avoiding increase in scale of a power storage unit, this power supply device includes: a power supply unit that supplies power fed from the power source to the microwave tube that is provided with a cathode, a heater for heating the cathode, an anode, and a collector; a power storage unit that stores the fed power and, if the voltage of the fed power decreases, supplies stored power that is power obtained by the power storing, to the microwave tube; and a power supply switching unit that, if the voltage of the fed power decreases, stops supplying the stored power to the anode and does not stop supplying the stored power to the heater.

Growing community of inventors

Tokyo, Japan

Naoki Iizuka