Castrol BioStat ST, a New Stern Tube Lubricant

Castrol launched a new stern tube oil range, Castrol BioStat ST, for use in stern tubes, CPP systems and stabilizers. It is based on selected synthetic esters and an optimized performance additive system. The lubricant has been specifically designed to provide a good level of lubrication and corrosion protection, good oxidation performance and hydrolytic stability.

Castrol BioStat ST is an Environmentally Acceptable Lubricant (EAL)^{that has been developed and tested to comply with the US Environmental Protection Agency Vessel Incidental Discharges Act (VIDA) 2018, with the lubricant being biodegradable, minimally toxic and not bio accumulative, as currently defined by the 2013 US VGP criteria.}

Offering improved oxidation, hydrolytic and thermal stability, Castrol BioStat ST also offers higher resistance to corrosion in the EMCOR test with synthetic seawater based on competitor analysis. Castrol BioStat ST emulsifies readily with sea water entering the stern tube to form a stable emulsion. This reduces the risk of free water which can severely impact stern tube components' health and performance.

Castrol’s BioStat ST is compatible and miscible in all proportions with Castrol BioStat^{and has also been tested and approved by key leading stern tube and sealing manufacturers. Castrol's Bio Range of Lubricants are carbon neutral in}