Cryogenics specialist Cryotherm GmbH & Co. KG has been commissioned to equip a new rocket test rig in Germany with supply lines of both liquid hydrogen (LH2) and liquid oxygen (LOX).

Powerful, modern rocket engines require liquid hydrogen and liquid oxygen as cryogenic fuels

Cryotherm’s customer is operating test facilities for rocket engines on its proving ground. Within this project, a new cryogenic upper stage for different launchers is under development. Test and qualification of the stage requires a new test facility, which will be situated on the test site in Germany.

Requirements for the testing phases of the new cryogenic upper stage at this test facility call for a guaranteed supply of LH2 and LOX for filling purposes. The LH2 supply is to be provided from an existing LH2 run tank at the test rig, while LOX is to be supplied via a LOX storage tank.

Kirchen/Sieg-based Cryotherm fitted the previous test rig with transfer pipes, valves, sensor technology and other cryogenic equipment back in 2003.

Following developments in the field of aerospace engineering in the past 12 years, however, the new project presents a number of special challenges, including the lowest operating temperature being 20 Kelvin (-253ºC); both the helium leakage rate and the stipulated heat ingress are of great importance.

For over 50 years Cryotherm has specialised in the manufacture of vacuum super-insulated storage and transport vessels, as well as pipelines for cryogenic liquefied gases, such as nitrogen, oxygen, argon, hydrogen and helium. In order to guarantee the extremely low level of incoming heat radiation on this new project, the company has not only carried out the engineering design of the panels for cooling down, degassing and flushing the entire cryogenic facilities but also the vacuum superinsulation technology in the hydrogen and oxygen lines.

The cryogenic system components transporting media are provided with superinsulation and are located in a vacuum jacket. These measures make it possible to comply with the extremely low heat ingress requirements permitted for the entire system.