PLASTIC SAFETY VALVE FOR RESERVOIRS Russian patent published in 2000 - IPC

FIELD: mechanical engineering; shutoff valves. SUBSTANCE: safety valve 1 has air inlet unit 2 and air outlet unit 3 built into valve housing 4 made in form of threaded plug. In case of pressure drop in inner space of reservoir on pan, caused by draining of liquid, valve diaphragm 11 of air inlet unit 2 opens to let air into space through safety valve 1 along arrow "a". Rigidity of valve plate 45 of air outlet unit 3 of safety valve 1 is calculated with due account of possibility of pressure rise in inner space to 80 mbar for stabilizing the space. If maximum indicated pressure value is exceeded, valve plate 45 opens to let air or gas out of space through safety valve 1 along arrow "b". EFFECT: enhanced reliability. 14 cl, 2 dwg