Canadian CG opts for SeaThigor seal for icebreaker retrofits

Canadian CG opts for SeaThigor seal for icebreaker retrofits
 The Thordon SeaThigor Seal

Thordon Bearings will provide the Canadian Coast Guard (CCG) with six SeaThigor shaft seals for retrofit to three purpose-built icebreakers.

CCG will retrofit its 5,910 GRT CCGS Pierre Radisson and sisterships CCGS Amundsen and CCGS Des Groseilliers, with two SeaThigor forward seals during scheduled dry-dockings over the next year.

SeaThigor is a seawater lubricated mechanical face seal. It has a safe return to port mode and is maintenance free to provide no visible or minimum leakage, long life and high operational reliability, and can withstand heavy-duty ice-breaking operations.

According to Scott Groves, Thordon Bearings’ regional manager – Americas, the vessels’ existing seals were leaking water into the machinery spaces, which meant they could not discharge oily-water overboard into Arctic waters.

The order, confirmed on the 1st of April, follows the success of the 2017 installation and subsequent operation of SeaThigor seals onboard 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.

“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,” said Scott Groves.

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 seals supplied to the Pierre Radisson-class of ships will also be the first SeaThigors designed with a split casing.

“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,” said Jasmin Racicot, from Thordon Distributor RMH Industries.