Development of a pre-screening-method for the qualification of environmentally acceptable lubricants for stern tube systems—The evaluation of friction efficiency and scuffing capacity

Abstract Lubricants for stern tube systems are subject to increasingly stringent requirements in terms of environmental compatibility, as any lubricant leakage leads contamination the sea. As a result, interest environmentally acceptable lubricants (EALs) is increasing. Biodegradable ester represent possible alternative conventional, mineral oil-based lubricants. In addition compatibility requirements, these must also meet tribological requirements. this study, suitable tribometers were therefore combined pre-screening method cost-effectively test their (friction efficiency, wear protection and scuffing capacity). For purpose, contact parameters transferred from real conditions system’s journal bearing standardized component tests (FZG gears FE8 rolling bearings) model on Mini-Traction-Machine (MTM, PCS Instruments). The result study EALs under application-related conditions, respectively. results show an influence composition friction efficiency fluid well transition point mixed friction. Furthermore, capacity could be shown. confirm high reproducibility those tests.