Thermo-Mechanical Cycling of the ROTAJOINT Flexible Interconnection Installed in a Parabolic Trough Test Facility

Abstract

Rotation and expansion performing assemblies (REPA) are one of the key components of parabolic-trough collectors (PTC) solar fields. This element is a flexible connector that connects the moving absorber tubes between adjacent PTCs or the absorber tubes to the fixed pipes of the solar field. A hybrid REPA model consisting of a flexible hose and a swivel joint, manufactured by the Spanish company ROTARM, has been installed in one of the PTC of a pilot plant at the Plataforma Solar de Almería (Spain) and tested to evaluate its life-time performance. Due to the lack of standardized procedure for testing this type of components for use in PTC solar fields, a test procedure has been defined consisting of a continuous thermo-mechanical cycling of the component to evaluate its performance under real conditions and to check any possible wear or failure. The total number of accumulated cycles has been 4000, which means that the tested REPA can withstand at least 10 years of trouble-free operation, if the periodic revisions and maintenance actions are carried out according to the manufacturer’s specifications.

Keywords

• Parabolic Trough
• Rotation and Expansion Performing Assemblies
• Flexible Hose
• Swivel Joint
• Thermal Cycling
• Mechanical Cycling