To provide a safety valve cap in an extremely low temperature container, hardly fixed to a valve body due to freezing even though the temperature of the valve body of an outer tank safety valve is lowered, certainly separated from the valve body by pressure applied by the action of a destroyed plate when a vacuum is destroyed by leakage of an inner tank, and having no interference with the function of the safety valve.
The cap 20 covering and attached to an opening in the valve body 17 of the outer tank safety valve 16 is formed of a synthetic resin, and a plurality of protruded lines 23 ensuring a clearance between the peripheral surface of the valve body and the inner peripheral surface of a circumferential wall with the opening of the valve body covered with the cap are arranged on the inner peripheral surface on the circumferential wall 21 of the cap.
ASANO NORIO
ASANO NORIO
| JPH1130385A | 1999-02-02 | |||
| JPH0361390U | 1991-06-17 |
| WO2002012782A1 | 2002-02-14 |
Higashio Masahiro
Torii Kazuhisa