Abstract: A laser welding head includes a shield gas injection nozzle and welding wire supply nozzle, wherein the shield gas injection nozzle and the welding wire supply nozzle include a main body section and a surface layer section that covers the main body section, and at least part of the surface layer section is formed by at least one of ultra-hard alloy, cermet and ceramics.

Abstract: A laser welding head includes a shield gas injection nozzle and welding wire supply nozzle, wherein the shield gas injection nozzle and the welding wire supply nozzle include a main body section and a surface layer section that covers the main body section, and at least part of the surface layer section is formed by at least one of ultra-hard alloy, cermet and ceramics.

Abstract: A heating laser beam is emitted to a cracked portion to remove moisture from the cracked portion, and subsequently, a welding laser beam is emitted to the cracked portion to heat and melt the cracked portion. The heating laser beam and the welding laser beam are emitted to an entire surface of the cylindrical body inside the reactor such as a stub tube penetrating through and fixed to a reactor bottom portion and a crack of the welded portion between the cylindrical body and the reactor bottom portion to thereby prevent a new crack from occurring and reactor water from leaking.

Abstract: A heating laser beam is emitted to a cracked portion to remove moisture from the cracked portion, and subsequently, a welding laser beam is emitted to the cracked portion to heat and melt the cracked portion. The heating laser beam and the welding laser beam are emitted to an entire surface of the cylindrical body inside the reactor such as a stub tube penetrating through and fixed to a reactor bottom portion and a crack of the welded portion between the cylindrical body and the reactor bottom portion to thereby prevent a new crack from occurring and reactor water from leaking.

Abstract: According to an embodiment, an in-pipe work device is inserted into a pipe and remotely controlled by a control device to perform an operation for an inner surface of the pipe. The in-pipe work device has: a main unit; a main-unit support unit; a rotation arm; a process head; a first distance sensor; and a process head position adjustment mechanism that changes a distance from a rotation center of the rotation arm to the process head. The control device makes the process head position adjustment mechanism expand and contract based upon a result of measurement by the first distance sensor and operation condition information that is input in advance.

Abstract: Fuel supply in an ultrasonic atomizer is conducted according to a fuel increment ratio pattern in which the increment of fuel in fuel increment control for starting and warming up is 70% or less of that in a typical conventional pressure injection valve system, thereby improving startability, accelerability and fuel consumption rate and further enabling a reduction in exhaust emissions. When the engine is started in low-temperature conditions, the fuel is supplied by continuous injection to make uniform and reduce the mean diameter of droplets of atomized fuel, thereby improving the ignitability and startability. The fuel injection start timing is varied in accordance with the combustion chamber temperature at the time of starting the engine, i.e.

Abstract: In a fuel supply system for internal combustion engine provided with a fuel injection valve and an ultrasonic atomizer on suction pipe of the engine, the tip of the oscillator member of said ultrasonic atomizer is furnished with an inclined portion and a portion with reduced portion further ahead of said inclined portion. By arranging a fuel supply passage face-to-face to this inclined portion, the shape of the oscillator tip is modified, and it is possible to maintain adequate atomizing angle regardless of the quantity of supply fuel without attaching the fuel on inner wall of inlet pipe, to increase the turndown ratio and to achieve even spraying all over the circumference. Also, it is possible to shorten the starting time when external air temperature is low and to increase the combustion performance and the exhaust property, particularly, in an engine using the fuel difficult to ignite at low temperature such as alcohol, kerosene, etc.