Shell Naturelle S4 Stern Tube Fluid 100
Shell Naturelle S4 Stern Tube Fluid 100 is an advanced biodegradable synthetic lubricant specifically developed for the lubrication and protection of marine stern tube bearing systems. Manufactured using fully saturated synthetic ester base fluids and advanced additive technology, the fluid delivers reliable lubrication performance while maintaining strong environmental compatibility. The product is classified as an Environmentally Acceptable Lubricant (EAL) and complies with the United States Environmental Protection Agency Vessel General Permit (EPA VGP), making it particularly suitable for marine vessels operating in environmentally sensitive waters.
One of the key benefits of Shell Naturelle S4 Stern Tube Fluid 100 is its high viscosity index, which allows the lubricant to maintain stable performance across a wide range of operating temperatures. The fluid provides low torque during system start-up at lower temperatures while maintaining an effective lubricating film at higher operating temperatures. This helps ensure consistent protection of stern tube bearings under varying marine operating conditions, supporting reliable equipment performance and reduced mechanical wear.
Shell Naturelle S4 Stern Tube Fluid 100 also offers excellent resistance to oxidation and hydrolysis due to its fully saturated ester base fluid formulation. Marine stern tube systems can be exposed to moisture, contaminants and varying temperature conditions during operation. The lubricant’s strong resistance to chemical degradation helps maintain oil stability and prolong service life compared with conventional mineral oils. This extended oil life can contribute to reduced maintenance frequency and improved long-term reliability of stern tube lubrication systems.
Another important advantage of Shell Naturelle S4 Stern Tube Fluid 100 is its strong wear protection performance. The lubricant contains advanced ashless and zinc-free additive technology designed to protect metal surfaces across a wide range of operating conditions. This helps reduce wear on stern tube bearings and other critical components, contributing to longer component life and improved operational reliability.
Shell Naturelle S4 Stern Tube Fluid 100 also helps maintain system efficiency through excellent load carrying capability and strong demulsification properties. Water contamination is common in marine environments and can compromise lubrication performance if not properly managed. The fluid’s ability to separate water quickly helps maintain clean lubricant and ensures effective lubrication of contact surfaces within the stern tube system.
The lubricant is specifically designed for marine stern tube applications where reliable lubrication and corrosion protection of stern tube bearings are required. It is widely used in commercial marine vessels where environmental compliance and high-performance lubrication are essential. The product also holds European Union Ecolabel certification, demonstrating its reduced environmental impact compared with conventional lubricants.
Physical characteristics include a kinematic viscosity of approximately 100 mm²/s at 40°C and 13.7 mm²/s at 100°C with a viscosity index of approximately 137. The fluid has a density of approximately 940 kg/m³ at 20°C, a flash point above 230°C and a pour point of approximately –30°C, supporting dependable lubrication performance in demanding marine operating conditions.
