Abstract: A pair of upper and lower pressure rollers 3, 4 is disposed so that their axes 15, 16 are tilted in a horizontal plane in respective directions opposite to each other with respect to a straight line perpendicular to a welding line of a joint portion J. The pressure rollers 3, 4 are positively driven by corresponding electric motors 63, 64 to thereby roll the joint portion. Thus, steps defined at the joint portion can be smoothed and a step gradient can be reduced to ensure a high degree of joint strength. Thus, it is possible to prevent a step portion from being interfolded into the base material of the meal plates 5, 6.

Abstract: An opening and closing device that opens and closes an access port opened from a substantially cylindrical working platform disposed inside a reactor vessel and used to access a nozzle stub of the reactor vessel from the inside of the working platform, the opening and closing device includes: a cover that is slidable along an outer peripheral surface or an inner peripheral surface of the working platform from a closing position where the access port is closed to an opening position where the access port is opened; and moving device for sliding the cover.

Abstract: A reactor vessel that performs work inside a nozzle stub of the reactor vessel, including a platform unit that is provided at an upper portion inside the reactor vessel and includes a substantially cylindrical side wall portion and a bottom portion blocking the lower end of the side wall portion; an access window that is provided at the side wall portion of the platform unit an access window moving device that opens and closes the access window; a working device; and a control device that is provided at the outside of the reactor vessel and controls the access window moving device and the working device, wherein the control device drives the access window moving device to open the access window, drives the working device to perform work inside the nozzle stub, and then drives the access window moving device to close the access window after the performance of the work.

Abstract: An opening and closing device that opens and closes an access port opened from a substantially cylindrical working platform disposed inside a reactor vessel and used to access a nozzle stub of the reactor vessel from the inside of the working platform, the opening and closing device includes: a cover that is slidable along an outer peripheral surface or an inner peripheral surface of the working platform from a closing position where the access port is closed to an opening position where the access port is opened; and moving device for sliding the cover.

Abstract: Disclosed is a nozzle stub working system for a reactor vessel that performs work inside a nozzle stub of the reactor vessel, the nozzle stub working system for the reactor vessel including: a platform unit that is provided at an upper portion inside the reactor vessel and includes a substantially cylindrical side wall portion and a bottom portion blocking the lower end of the side wall portion; an access window that is provided at the side wall portion of the platform unit to allow the inside of the platform unit to communicate with the nozzle stub; an access window moving device that opens and closes the access window; a working device that advances from the inside of the platform unit to the inside of the nozzle stub to perform work inside the nozzle stub; and a control device that is provided at the outside of the reactor vessel and controls the access window moving device and the working device, wherein the control device drives the access window moving device to open the access window, drives the workin

Abstract: A pair of upper and lower pressure rollers 3, 4 is disposed so that their axes 15, 16 are tilted in a horizontal plane in respective directions opposite to each other with respect to a straight line perpendicular to a welding line of a joint portion J. The pressure rollers 3, 4 are positively driven by corresponding electric motors 63, 64 to thereby roll the joint portion. Thus, steps defined at the joint portion can be smoothed and a step gradient can be reduced to ensure a high degree of joint strength.

Abstract: A pair of upper and lower electrode wheels 1, 2 are disposed so that their axes 17, 18 are tilted in a horizontal plane in respective directions opposite to each other with respect to a straight line Y perpendicular to a welding line X defined on overlapping portions (L) of two metal plates 5, 6, and mash seam welding is performed while positively driving electric motors 61, 62. This can reduce the increased amount of thickness and step gradient of a joint portion to reduce a stress concentration factor and ensure joint strength. The metal plates are joined to each other such that a nugget N is not deviated from a joint interface. Therefore, it is possible to prevent respective ends of the metal plates at the overlapping portions L from biting into and scratching the corresponding electrode wheels 1, 2 and to prevent spattering during the welding.

Abstract: A radiation treatment apparatus includes a guide and a support member. The guide moves a radiation generating unit along an orbit with a predetermined radius such that an X-ray emitted from the radiation generating unit may cross an isocenter. The support member rotates the guide about a turning axis passing through the isocenter. The radiation generating unit is moved along a spherical plane by the guide and the support member and applies the X-ray toward the isocenter in multiple directions.

Abstract: The radiotherapy apparatus in the present invention includes a bed, a radiation irradiating head, head swing mechanisms, a precise inspection unit and a control unit. The bed carries a subject. The radiation irradiating head irradiates a treatment radiation to a treatment field of the subject. The head swing mechanisms, which are coupled to the radiation irradiating head, swings the head of the radiation irradiating head so that the treatment radiation emitted from the radiation irradiating head pursues the motion of the treatment field. The precise inspection unit obtains a diagnosis image containing the treatment field. The control unit controls the positions of the head swing mechanisms so that an irradiation field of the radiation irradiating head pursues the treatment field, based on the diagnosis image, the position of the radiation irradiating head and the state of the swung head.

Abstract: A radiotherapy apparatus comprising an irradiation head having a linear accelerator and an intra-head waveguide unit whose one end portion is electromagnetically connected to the linear accelerator, a supporting moving mechanism which supports and moves the irradiation head on predetermined first spherical coordinates, a microwave oscillator which generates microwaves to be supplied to the irradiation head, and which is placed in a stationary position, a fixed waveguide unit having one end portion electromagnetically connected to the microwave oscillator, and the other end portion positioned on the supporting moving mechanism, and a moving waveguide unit having one end portion electromagnetically connected to the other end portion of the fixed waveguide unit positioned on the supporting moving mechanism.

Abstract: A radiation treatment apparatus includes a guide and a support member. The guide moves a radiation generating unit along an orbit with a predetermined radius such that an X-ray emitted from the radiation generating unit may cross an isocenter. The support member rotates the guide about a turning axis passing through the isocenter. The radiation generating unit is moved along a spherical plane by the guide and the support member and applies the X-ray toward the isocenter in multiple directions.

Abstract: A radiotherapy apparatus comprising an irradiation head having a linear accelerator and an intra-head waveguide unit whose one end portion is electromagnetically connected to the linear accelerator, a supporting moving mechanism which supports and moves the irradiation head on predetermined first spherical coordinates, a microwave oscillator which generates microwaves to be supplied to the irradiation head, and which is placed in a stationary position, a fixed waveguide unit having one end portion electromagnetically connected to the microwave oscillator, and the other end portion positioned on the supporting moving mechanism, and a moving waveguide unit having one end portion electromagnetically connected to the other end portion of the fixed waveguide unit positioned on the supporting moving mechanism.

Abstract: The radiotherapy apparatus in the present invention includes a bed, a radiation irradiating head, head swing mechanisms, a precise inspection unit and a control unit. The bed carries a subject. The radiation irradiating head irradiates a treatment radiation to a treatment field of the subject. The head swing mechanisms, which are coupled to the radiation irradiating head, swings the head of the radiation irradiating head so that the treatment radiation emitted from the radiation irradiating head pursues the motion of the treatment field. The precise inspection unit obtains a diagnosis image containing the treatment field. The control unit controls the positions of the head swing mechanisms so that an irradiation field of the radiation irradiating head pursues the treatment field, based on the diagnosis image, the position of the radiation irradiating head and the state of the swung head.

Abstract: In a sterilizing apparatus, a first electrode is provided in a chamber, and a target to be sterilized is supported by the first electrode. The first AC power supply is connected to the first electrode to supply AC power to the first electrode such that a plasma is generated around the first electrode. The DC pulse power supply is connected to the first electrode to supply DC pulse power to the first electrode such that ions or electrons are accelerated toward the target.

Abstract: According to the invention, the rear end of a preceding metal piece and a front end of a succeeding metal piece are heated, pressed and joined prior to the finishing hot rolling. An alternating magnetic field running through the metal pieces in the thickness direction thereof is generated in an end region on opposed faces of the respective metal pieces to perform heating. Another alternating magnetic field whose direction is reverse with respect to that of the former alternating magnetic field is partially generated in the end region on the opposed faces of the metal pieces and in either a region where the metal pieces exist or a region outside width ends of the metal pieces. This assures a uniform heating of the end region on the opposed faces of the metal pieces over their full width to reliably join the both metal pieces to each other.

Abstract: A method and apparatus for joining metal pieces wherein the rear end of a preceding metal piece and a front end of a metal piece are heated and then pressed together prior to hot finished rolling. The temperature the ends of the metal pieces are heated to is a temperature range between the solidus and liquidus line temperatures of the metal(s) to be joined.

Abstract: According to the invention, the rear end of a preceding metal piece and a front end of a succeeding metal piece are heated, pressed and joined prior to the finishing hot rolling. An alternating magnetic field running through the metal pieces in the thickness direction thereof is generated in an end region on opposed faces of the respective metal pieces to perform heating. Another alternating magnetic field whose direction is reverse with respect to that of the former alternating magnetic field is partially generated in the end region on the opposed faces of the metal pieces and in either a region where the metal pieces exist or a region outside width ends of the metal pieces. This assures a uniform heating of the end region on the opposed faces of the metal pieces over their full width to reliably join the both metal pieces to each other.

Abstract: Method and apparatus for joining metal pieces using induction heating. Metal pieces to be joined are placed end-to-end with a gap between them and induction heated in the thickness portion. To maximize speed and even heating edge-to-edge of the ends, members of a magnetic substance are provided in a gap between the inductor and the piece to be heated, thereby enhancing local heating effect by increasing magnetic flux density. Once heated, the ends are pressed together end-to-end for joining.

Abstract: An apparatus for joining metal pieces using induction heating. Preceding and succeeding metal pieces are followed by a carriage which carries an inductor. The inductor has the ability to move in the longitudinal direction of the metal pieces relative to the carriage to allow the inductor to move more or less upon the preceding or succeeding metal pieces to increase or decrease the induction heating effect, thereby taking into account any thickness variation of the metal pieces and yet still heating them evenly with regard to each other, prior to their being pressed against each other for joining before hot finishing rolling.

Abstract: According to the invention, the rear end of a preceding metal piece and a front end of a succeeding metal piece are heated, pressed and joined prior to the finishing hot rolling. An alternating magnetic field running through the metal pieces in the thickness direction thereof is generated in an end region on opposed faces of the respective metal pieces to perform heating. Another alternating magnetic field whose direction is reverse with respect to that of the former alternating magnetic field is partially generated in the end region on the opposed faces of the metal pieces and in either a region where the metal pieces exist or a region outside width ends of the metal pieces. This assures a uniform heating of the end region on the opposed faces of the metal pieces over their full width to reliably join the both metal pieces to each other.