The Internal Tank Valve is a fail safe isolation valve for bottom and side withdrawal tanks. It is sometimes refered to as an emergency tank shut off valve.
They are commonly installed in storage tanks that contain dangerous or flammable liquids or gases such as LNG, Chlorine, Propane, Propylene or Ammonia etc. In the event of an emergency the air supply provided by air actuators placed on the tank is interupted. A weight or a spring slams the inlying valve shut, securing the tank and it's contents.
