COMPAC bearings are at the heart of the award-winning open seawater lubricated propeller shaft bearing system.The COMPAC polymer alloy bearing is homogeneous (there are no layers of differing materials) with properties that are consistent throughout the wall thickness. The Thordon COMPAC bearing is designed in a 2:1 L/D configuration in the AFT bearing.To promote early formation of a hydrodynamic film between the shaft and bearing, the lower (loaded) portion of the bearing is smooth, while the upper half of the bearing incorporates grooves for flow of the water lubricant/coolant. And although start-up friction is initially higher than an oil system, at rated shaft speeds, viscous friction acting on the rotating shaft is lower with seawater than with oil. This has been shown to lead to fuel savings and thus reduced emissions. A key benefit of the seawater system is that it negates the need for a damage-prone aft seal.

A Thordon COMPAC open seawater lubricated propeller shaft system offers considerable advantages to ship owners, not only in bearing wear life predictability and reliability, but they are also cheaper to maintain, easier to install and are future compliant.

The COMPAC system typically includes COMPAC bearings, shaft liners, a Water Quality Package, ThorShield shaft coating and a forward seal.

  • Zero pollution risk (no oil required)
  • 15-Year Wear Life Guarantee for COMPAC in bluewater  operation*
  • Turnkey engineering and installation support
  • Easy fitting
  • Reduced seal maintenance costs
  • Inspections without shaft withdrawal
  • Resistance to shock and edge loading
  • Survivability (our non-catastrophic failure mode allows ship to get to port)
  • Global availability

“We chose Thordon COMPAC for this vessel because these bearings are environmentally friendly, water lubricated and come with no risk of pollution.”

– Captain Simon Merritt, Technical Manager of Carisbrooke Shipping Ltd. (U.K.) 

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