If the vacuum that partially insulates the lines breaks, the helium can heat up abruptly and thus expand greatly. Very large safety valves are used, but they are not directly exposed to the cryogenic temperature. Particle accelerators, however, are not necessarily the most common facilities found anywhere. Where can you find these or similar conditions as well? Cryogenic helium cooling can be found in the following applications, for example:
Again, it should be noted in the design that many safety valves are required for very low temperatures by design but are still decoupled from the primary process. They then only have to discharge the cryogenic medium in the event of overpressure. This is why many Semi Nozzle 441 Safety Valves are used in the processes at DESY, although LESER recommends Full Nozzle safety valves and stellited discs and seats for permanent cryogenic use.
