| 摘要 |
PURPOSE:To improve safety of an ultrahigh-pressure vessel by fitting liquid- tightly a piston having a stepped shape into the large-diameter hole and small- diameter hole of a cylindrical member and supplying a pressure medium into the space between the cap on the side of the cylindrical member to be fitted with the piston and the end face of the large-diameter part of the piston. CONSTITUTION:An inside cylinder 2 is inserted into an outside cylinder 1 by providing a clearance 11 therebetweeen. A pressure medium is supplied into the cylinder 2 so as to overflow through an overflow port 6. An upper cap 3 set with a pressure increasing piston 4 having a stepped shape is then fitted to the upper part of a vessel. A check valve 12 is then opened to discharge the excess pressure medium through a discharge port 7. While a pressure vessel is kept supported to a press frame, the pressure medium is supplied through a supply port 7 and is supplied via introducing and discharging passages 8, 9 into the clearance 11; at the same time, the pressure medium is introduced into the clearance 10 as well. The pressure of the piston 4 is thus increased and the valve 12 is actuated by the descending piston 4, by which an internal pressure P2 is maintained. |
