Description

The Model 3700 manhole and emergency pressure vents provide emergency pressure relief beyond that furnished by the normal pressure vent for atmospheric and low pressure tanks, as well as providing a convenient access for tank cleaning, inspection and repair. Emergency relief valves provide relief from excessive internal pressure which may be caused by an abnormal condition, such as ruptured internal heating coils or an external fire. The Model 3700 does not provide vacuum relief and therefore vacuum relief must be supplied by the normal operating vent. For vacuum relief see Valve Concepts Models 3100, 3200, 3300 and 3600 series vents.