New shaft seal has SRTP benefit

The Thordon BlueWater Seal is a commercial grade axial lip seal specifically designed for merchant shipping fleets. It seal incorporates a secondary Safe Return to Port emergency seal. This inflates in the event of damage to the primary seal, allowing the shaft to continue to turn, allowing the vessel and crew to return safely to the nearest port. First used in the company’s TG100 and SeaThigor, designed for the workboat and specialized naval vessel markets respectively, it represents the first SRTP seal designed for the merchant fleet.

As well as its SRTP capability, the seal features a RENFORM main seal ring. This technology, developed in-house by Chief Research Engineer Gary Ren, allows the facing elements of the seal to operate almost without any friction. In practical terms, it means the seal is much better suited to variable and low draught conditions – a key benefit to a globally-operating merchant ship.

During comparative trials on Thordon’s full-scale test rig in Ontario, Canada, the seal operated without friction spikes and considerably less friction than similar seals leading to reduced wear, longer life and less maintenance. Thordon Bearings confirmed to The Motorship that the new seal was expected to lead to marginal fuel efficiency savings estimated at “0.5-1.0%”. 

The COMPAC system includes Thordon’s proprietary seawater lubricated COMPAC bearings, shaft liners, ThorShield anti-corrosion shaft coating, a Thordon Water Quality Package, a Thordon Bearing Condition Monitoring System, and, now, the new BlueWater Seal.

The seal can be installed to all vessels with shaft diameters between 300mm to 1000mm (11.8in to 39.4in) and is simple to install, operate and maintain.

Class approvals have been received from ABS, LR, DNV, BV and CCS.

Thordon Bearings was also working on a project with a major shipyard and naval architect to investigate the possibility of eliminating the stern tube. This would be likely to improve the economics of adding a water lubrication option to existing and future series designs, The Motorship heard.