Thordon Bearings has received a Canadian Coast Guard contract to supply six SeaThigor shaft seals for retrofit installation to three purpose-built icebreakers.
The 5,910grt CCGS Pierre Radisson, named after the 17th-century French fur trader and explorer, along with sisterships CCGS Amundsen and CCGS Des Groseilliers, will each be retrofitted with two SeaThigor forward seals during scheduled drydockings over the next year.
The order, confirmed on the 1st of April, follows the success of the 2017 installation and subsequent operation of SeaThigor seals aboard the oceanographic and hydrographic survey vessel CCGS Hudson, for which a procurement agreement was signed with the Government of Canada under its Build in Canada Innovation Program (BCIP).
Due to the success of that first SeaThigor installation, the government permitted the Canadian Coast Guard (CCG) to deal directly with Thordon Bearings without either party having to go through a competitive bid process, via the BCIP – Additional Sales.
Scott Groves, Thordon Bearings’ Regional Manager – Americas, said: “This is a significant order for Thordon Bearings, marking not only the SeaThigor seal’s first-ever reference onboard a purpose-built icebreaker but also the largest propeller shaft seals we have ever manufactured.”
The 98.2m (322ft) long, 1200-class vessels are designed to Arctic Class 3 requirements and operate twin 674mm (26.5in) diameter shafts driving fixed pitch propellers. Propulsive power is generated by six Alco M251F main engines delivering 10142kW of power.
“The vessels’ existing seals were leaking water into the machinery spaces, which meant they could not discharge oily-water overboard into Arctic waters. Ultimately, CCG needed a seal solution that was robust enough to withstand heavy-duty ice-breaking operations, without leaking. SeaThigor provides that level of robustness,” continued Groves.
The seals supplied to the Pierre Radisson-class of ships will also be the first SeaThigors designed with a split casing, as Carl Sykes, Manager of Thordon’s Global Service & Support division, explained.
“The limited space available in the vessels’ engine room prevented the installation of a SeaThigor seal with a conventional, fully encased bronze housing. So, we designed a seal with a split casing to simplify the installation and commissioning process, allowing engineers to access the underside of the seal. Many different departments – procurement, design, engineering and manufacturing – came together to really make this happen. It was a complete team effort.”
Jasmin Racicot from Thordon’s Quebec-based distributor RMH Industries, added: “What interested CCG about the SeaThigor was the seal’s emergency safe-return-to-port function and low maintenance requirement; the silicon carbide faces are designed for reduced wear and tear throughout its operational life, resulting in improved life cycle costs for the Coast Guard.”
CCG is a long-standing customer of both Thordon Bearings and RMH, with a number of vessels operating Thordon’s seawater lubricated COMPAC bearing system.
One of the first CCG vessels to benefit from COMPAC was the 6098gt CCGS Des Groseilliers, which was installed with the system 17-years-ago. It will be fitted with a SeaThigor seal at a scheduled drydocking in 2020. CCGS Amundsen will be converted to COMPAC at its next drydocking, when the SeaThigor seals will also be installed.