The 3rd volume of "Engineering Innovations" includes articles reflecting the research results and describing technical solutions in the fields of mechanical engineering and technology development. Numerical analysis of slip flow and heat transfer with ohmic heating between rotating and stationary discs, pretreatment process on brine after reverse osmosis desalination as electrodialysis feed, and results of design and testing of rotary friction welding machine are presented in this volume. Readers will also be interested in investigations of usage features of glass fiber reinforced plastic in the shipbuilding and parametric analysis of MOSFET-based absorber for 5G base station. The presented articles will be appreciated by many engineers, technologists, academics, and students.