Why is a safety shut-off valve important for cryogenic containers?

With a new safety shut-off valve (SAA), Goetze KG Armaturen completes its product portfolio for cryogenic applications. The valve was specially developed to safeguard the filling process of stationary cryogenic containers. In the event of an impermissible increase in pressure, it closes the filling line and thus interrupts the further delivery of the medium by the tanker.

When filling a stationary cryogenic container, cryogenic liquefied gases are conveyed from the tanker into the storage tank. If an impermissible increase in pressure occurs during this time, the safety shut-off valve complements the protective function of the safety valve: it interrupts the filling flow and prevents medium from continuing to be pumped.

In this way, the SAA takes on a clearly defined task: it safeguards the filling process – it does not replace the safety valve of the container.

In normal operation, the main valve is open. A pressure switch monitors the pressure in the vessel via a separate control line. When the set response pressure is reached, the pressure switch triggers the mechanical closing function. A preloaded spring closes the main valve and shuts off the filling line. An integrated position indicator shows directly from the outside whether the valve is Open or Closed. This allows the current state to be quickly identified.

In addition to the safety function, the focus of the development was on operability and practicality. The closed construction in the lower area reduces the penetration of dirt and insects into the mechanics. The cover has a defined position and is easy to assemble and disassemble. After a trip, the valve can be manually reset with a special clamping tool.

The safety shut-off valve is suitable for typical cryogenic media such as liquid nitrogen, liquid oxygen, liquid argon and liquid CO₂. The temperature range is from −196 °C to +65 °C.

For applications with extended requirements, the SAA is also available with two pressure switches. In addition to the container pressure, the pressure in the upstream filling line can also be monitored. If one of the two pressure switches responds, the main valve is closed.

This variant offers an additional option, especially in demanding CO₂ applications, to protect upstream equipment from an impermissible increase in pressure during filling.

The new safety shut-off valve is available as a stainless steel and gunmetal version. GOETZE thus completes its existing portfolio for cryogenic storage containers with another solution for thehandling of cryogenic liquefied gases.