Castrol launches BioStat ST
Castrol has launched a new stern tube oil range, Castrol BioStat ST for use in stern tubes, CPP systems and stabilisers
Castrol launches BioStat ST , a new stern tube lubricant
Pangbourne
04 March 2025
Castrol, a global leader in lubricants and part of the bp group, has launched a new stern tube oil range, Castrol BioStat ST. The stern tube oil range is for use in stern tubes, CPP systems and stabilisers. It is based on selected synthetic esters and an optimised performance additive system. The lubricant has been specifically designed to provide a very good level of lubrication and corrosion protection, good oxidation performance and hydrolytic stability.
Castrol BioStat ST is an Environmentally Acceptable Lubricant (EAL)1 that has been developed and tested to comply with US Environmental Protection Agency’s2, 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 according to Castrol analysis, can severely impact stern tube components health and performance.
Castrol’s BioStat ST is compatible and miscible in all proportions with Castrol BioStat3 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 accordance with BSI PAS 2060 since 20214.
Eda Gökay, Global Marine and Energy Marketing Manager, Castrol, said, “Castrol BioStat ST demonstrates our commitment as an end-to-end lubrication service provider. It is a clear example of our mission to deliver high-performing EALs1 which are biodegradable, minimally toxic, and non-bio accumulative5 lubricants that provide the equipment protection the maritime sector depends on while meeting complex regulatory targets.”
Eda Gökay added, “For 125 years, Castrol has been at the forefront of market-leading lubricant solutions, and the latest Castrol BioStat ST product is another example of our proactive approach to meeting our customers’ needs. It provides operators and crew with a reliable lubricant proven to deliver improved performance and stern tube health.”
As with its entire Bio product range, the use of Castrol BioStat ST will be supported by the Castrol team, providing hands-on support as well as technical services. This includes Castrol’s condition-based monitoring services, such as its recently launched Castrol SmartMonitor, which combines IoT Technology with Castrol’s extensive engineering experience.