Abstract: Disclosed is an X-ray exposure apparatus comprising a chamber, filled with X-ray low attenuation gas for guiding X-rays, generated from an X-ray source, to an X-ray window, a gas supplying portion, provided to supply X-ray low attenuation gas into the chamber and having a portion with a small-diameter passage cross section formed at least at a part thereof, a gas discharging portion, provided to discharge gas from the chamber and having a portion with a small-diameter passage cross section formed at least at a part thereof, and a flow-rate controller for controlling a flow rate of the gas to be supplied to the gas supplying portion to thereby control pressure in the chamber, whereby pressure in the chamber is made equal to or slightly higher than atmospheric pressure by setting the small-diameter portion of the gas supplying portion smaller than that of the gas discharging portion.

Abstract: An X-ray radiation apparatus comprises a synchrotron 11 that generates X rays, an X-ray reflecting mirror 13 that reflects X rays emitted from the synchrotron 11, a mirror driving mechanism that enlarges the X-ray illumination area by oscillating the mirror 13, a beryllium window 14 that is connected to the synchrotron-side housing base containing the mirror 13 by means of a bellows 17 and that allows the X rays reflected by the mirror 13 to be taken out of the vacuum environment, and a window driving mechanism 18 that moves the window 14 along with the movement of the X-ray illumination position by oscillating the window 14 in synchronization with the oscillation of the mirror 13. With this arrangement, the X rays coming from the window 14 pass through the X-ray mask 15 and fall upon the specimen 16 to replicate the mask pattern into the specimen.

Abstract: A rotary valve which includes a valve sleeve having a cylindrical internal cavity and a plurality of axial grooves formed on the wall surface of the internal cavity; a valve spool fitted in the internal cavity of the valve sleeve and rotatable relative to the valve sleeve for controlling flow of a pressurized fluid through the valve; an annular groove formed at least at one end of the valve sleeve and having a diameter larger than that of the internal cavity; a bush fitted in the annular groove and having a hole of the same diameter as the internal cavity of the valve sleeve; a seal material interposed between engaging surfaces of the bush and annular groove; chamfered surface formed at the outer corner edge of the bush; and an annular thin-wall portion formed at the end of the valve sleeve and bent radially inward to retain the bush in the annular groove.

Abstract: In the manufacturing of a spiral pipe, there is first determined a maximum curvature which should be imparted to a strip of pipe forming material in order that a desired residual moment will be imparted to the finished pipe after the strip bent to the maximum curvature is allowed to spring back from the bent condition, which maximum curvature is determined based on the thickness, Young's modulus and yield stress of the strip, the desired curvature of the finished pipe, and the residual moment to be imparted to the finished pipe. By adjusting the position of three rows of forming rolls positioned at the apexes of a triangle, the flat strip is continuously bent into a spiral that has the thus determined maximum curvature.

Abstract: Rolled steel plate is press-fabricated into cylindrical UO pipe with a large wall thickness, by the steps of crimping, U-ing and O-ing. In the U-ing process, a collapsible U-ing punch, including a center block carrying paired side punches on both sides and a bottom punch at the bottom, is used. The U-ing punch insures that the O-shaped workpiece has the desired butt gap by decreasing the ratio of its height to its width when the gap proves to be smaller than the desired butt edge gap, and vice versa when the gap proves to be larger than the desired butt edge gap.