Cryo Component Test of Herschel EPLM

The Herschel satellite is a space based telescope designed for the investigation of sub millimeter radiation from astronomical objects. The cryogenic system is an essential part of the telescope’s Extended Payload Module (EPLM). The cryogenic system has to provide an environment of sufficiently low temperatures to assure the proper functioning of the scientific payload.

Main component of the cryogenic system is the cryostat, a huge vacuum vessel (see: Figure 1) with various cryogenic components inside. In order to qualify the components of the cryogenic system, multiple tests such as leak tests, thermal cycle tests, pressure cycle tests and vibration tests are performed.

In this paper the test program for two cryo components, the rupture disc and a safety valve is discussed. The testing philosophy is presented and selected results of tests at ambient and low temperatures are shown.