Where published:
Year:2025
Water-injected and lubricated compressors face specific complications due to water low viscosity, poor film formation, causing high corrosivity, leading to potential wear and abrasion damage. Therefore, certain coatings are required to address the wear and corrosion challenges on the rotor helical surfaces to maintain their safe operating characteristics, especially in their direct drive configuration. A coating provides homogeneous surface qualities with low material utilisation, making it an efficient and economical solution to the high cost of advanced bulk materials. This study reviewed various coating methods and materials for water-lubricated rotors. The coating processes can be utilised by electrodeposition, physical vapour deposition (PVD) techniques, chemical vapour deposition (CVD) techniques, and thermal spray. Several additional methods are also explored, such as the wet paint spray coatings, and dip coatings. A wide range of coating materials are reviewed in this study, such as alloys, tungsten carbide-cobalt (WC–Co), tungsten carbide-cobalt-chromium (WC–CoCr), graphite composites, molybdenum disulphide, diamond-like carbon (DLC), carbides and flash carbide (WC–10Co–4Cr). Wear resistance and hydrophilicity are assessed for carbon fibre composites and polymers such as hydrophilic polyether ketone (PEEK) and polytetrafluoroethylene (PTFE). By concentrating on “as-coated” solutions, the study presented in this paper seeks to find materials and procedures that maintain rotor clearances while satisfying functionality and cost-efficiency of water injected screw compressors. The results shed light on the advanced solutions, process optimisation, and material selection for the water-lubricated compressors.