Abstract: This high-frequency hardening apparatus is provided with: an induction heating coil which has a U-shaped part that sandwiches a turbine blade, a pair of linear parts, and a connection part connecting the U-shaped part and the linear parts; a temperature detection unit which detects, in a non-contact manner, temperature around the induction heating coil; a moving mechanism which relatively moves the turbine blade and the induction heating coil in the direction of blade height; an electrical current supply unit which supplies a high-frequency electrical current to the induction heating coil; and a control device which has an electrical current control unit that, on the basis of a detection value provided by the temperature detection unit, controls the magnitude of the high-frequency electrical current supplied from the electrical current supply unit such that the detection value will not exceed a predetermined temperature.

Abstract: A burnishing device and method are provided that enable burnishing processing to be reliably performed on a surface included in an object to be processed and having a change in height and inclination angle. The device includes a burnishing tool having a pressing unit that rotationally presses a surface of an object to be processed, the surface having a change in height and inclination angle; a tool driving device configured to move the burnishing tool; a strain sensor configured to detect the strain amount of the burnishing tool; and a computer that calculates pressing force to be applied by the pressing unit in a normal direction of the surface of the object to be processed, calculates correction amount of displacement of the tool driving device in a pressing direction based on calculated pressing force and stored pressing force in advance, and outputs the correction amount to the tool driving device.

Abstract: A steam turbine having a fork-type joint structure is provided that secures sufficient strength for endurance of stress corrosion cracking, low-cycle fatigue, and high-cycle fatigue, and extends an operating life while making it possible to endure long-term operation. The turbine includes a rotor having a plurality of rotor forks rowed in an axial direction; a turbine blade having blade forks arranged in the axial direction of the rotor, the blade forks engaged with the rotor forks; a plurality of pin holes whose positions are different from each other in the radial direction of the rotor; and a plurality of fork pins inserted into the plurality of pin holes in the axial direction of the rotor. A clearance exists between an inner diameter of the pin hole of the blade fork and a diameter of the fork pin, the clearance varying depending on positions in the axial direction of the turbine.

Abstract: A burnishing device and method are provided that enable burnishing processing to be reliably performed on a surface included in an object to be processed and having a change in height and inclination angle. The device includes a burnishing tool having a pressing unit that rotationally presses a surface of an object to be processed, the surface having a change in height and inclination angle; a tool driving device configured to move the burnishing tool; a strain sensor configured to detect the strain amount of the burnishing tool; and a computer that calculates pressing force to be applied by the pressing unit in a normal direction of the surface of the object to be processed, calculates correction amount of displacement of the tool driving device in a pressing direction based on calculated pressing force and stored pressing force in advance, and outputs the correction amount to the tool driving device.

Abstract: A steam turbine having a fork-type joint structure is provided that secures sufficient strength for endurance of stress corrosion cracking, low-cycle fatigue, and high-cycle fatigue, and extends an operating life while making it possible to endure long-term operation. The turbine includes a rotor having a plurality of rotor forks rowed in an axial direction; a turbine blade having blade forks arranged in the axial direction of the rotor, the blade forks engaged with the rotor forks; a plurality of pin holes whose positions are different from each other in the radial direction of the rotor; and a plurality of fork pins inserted into the plurality of pin holes in the axial direction of the rotor. A clearance exists between an inner diameter of the pin hole of the blade fork and a diameter of the fork pin, the clearance varying depending on positions in the axial direction of the turbine.