The role of hydrogen and its effects on bearings in compressor applications

Abstract

The hydrogen market is growing and becoming more and more relevant for future energy systems. It is, therefore, necessary to know what role hydrogen will play in the energy system, and for what applications it will be used. Most hydrogen applications utilize compressed hydrogen which makes this relevant for SKF, as hydrogen compressors contain bearings. The bearing material is likely to be exposed to hydrogen in these applications, making it necessary to know how susceptible the bearings are to hydrogen embrittlement. To answer these questions were a literature study of the future of hydrogen and a market study of the compressor market done. A lab trial was also performed, where bearings made of 100Cr6 grade steel were cathodically charged with hydrogen before being tested in a test rig. It was found that hydrogen is likely to play a significant role in the future energy system, as a potential fossil-free energy carrier. Both the demand for hydrogen and the number of applications are growing. Infrastructural applications will probably be widely used as they are a key part of hydrogen becoming a part of the energy system. To compress hydrogen a wide variety of compressors will be used as different applications use different amounts of hydrogen at different pressures, where mainly reciprocating and centrifugal compressors are highlighted as the most promising alternatives. The lab tests showed that the charging was detrimental to the material, which broke after only a short time in the test rig. With the equipment available could it however not be proven that this is due to hydrogen embrittlement, although that is the most likely cause. The 100Cr6 EN ISO 683-17 grade steel is thus not suitable for hydrogen applications.