With the N-ARPEX coupling, Siemens is presenting an additional series in the field of torsionally rigid all-steel multi-plate couplings with improved performance data. An optimized plate pack and a revised component design enable the transmission of higher torques and speeds as well as a larger bore capacity for standard hubs. All-steel couplings can be used in all applications where reliable torque transmission with simultaneous shaft misalignment is required. The couplings are designed for an explosive environment in accordance with Directive 2014/34/EU and meet the requirements of API610/ISO 13709 and API671/ISO 10441. The all-steel couplings are designed as standard for low temperatures of up to -50 degrees Celsius - up to ten degrees better than previous versions of the ARPEX series.