Finally, a Stern Tube Bearing Guaranteed to Last the Life of the Vessel!

Lifetime Bearing Wearlife Guarentee

Our COMPAC bearing system is proven to last!  We have references on 550+ commercial vessels that use seawater lubricated shaftlines and we are backing that up with a lifetime bearing wearlife guarantee.

Thordon is offering this guarantee because of the proven performance and wear life with the COMPAC propeller shaft bearings operating in commercial vessels over the last 25 years.   Using the proven principles of seawater lubrication, Thordon’s COMPAC propeller shaft bearing system will reduce your operating and maintenance costs with its reliable performance.  We don’t believe in selling spare parts!  The 100% pollution free system is future compliant and has zero environmental impact.

Get on board and find out for yourself why Thordon is the proven choice.

“It's a No Brainer! A seawater lubricated shaft means there is less to worry about.”

– Andy Wright, Fleet Operations Director | Technical Operations,
Holland America Group | Serving Princess Cruises

COMPAC System Strip

COMPAC Lifetime Bearing Wearlife Guarantee

The Thordon seawater lubricated COMPAC bearing is guaranteed to meet Classification Society propeller shaft bearing wear specifications for the lifetime of the vessel or Thordon Bearings will supply new bearings free of charge.*


Commercial newbuild ship owners of Classed ships with stern tube (single/twin screw) with shaft diameter of 300mm (12”) or greater. The program excludes vessels such as naval/coast guard/government vessels.  COMPAC conversions may also be considered on a case by case basis.


The ship owner must clearly specify the complete COMPAC system (see below) to the shipyard in order to qualify for the lifetime bearing wearlife guarantee. There will be a full technical signoff by Thordon Bearings prior to issuance of the lifetime wear life guarantee.   A copy of the specification is available from Thordon.

COMPAC Propeller Shaft Bearing System:

The COMPAC propeller shaft bearing system specification includes:

a) COMPAC propeller shaft bearings for shafts of 300mm (12”) or greater

b) Thordon Water Quality Package

c) Shaft liners

d) ThorShield shaft coating

e) Forward seal (SeaThigor or Blue Water or seal approved by Thordon Bearings)

Items a, b, c, and d must be supplied by Thordon. Item e must be approved by Thordon before issuance of the guarantee. If bearing carriers are a required part of the design, they would also be supplied by Thordon Bearings.

* What is the Guarantee?

The Thordon seawater lubricated COMPAC bearing system is guaranteed to meet Classification Society propeller shaft bearing wear specifications for 25 years or Thordon Bearings will supply new bearings free of charge. The guarantee is limited to the supply of replacement bearings delivered to the ship. It does not include replacement of any other Thordon supplied components nor any drydocking or installation costs.  Standard operating parameters as specified by Thordon Bearings (for example – system maintenance, minimum water flows, etc.) must have been provided and maintained by the ship owner.

The guarantee is limited to the owner of the ship. If the ship were sold, the balance of the time outstanding on the guarantee can be transferred to the new ship owner for a fee (25% of price of fully machined set of bearings). The guarantee would be issued by Thordon Bearings directly to the shipowner or his designate and would not be offered through the shipyard.

Thordon is offering this guarantee because of our confidence in Thordon COMPAC propeller shaft bearings and the proven experience and wear life of COMPAC bearings operating in commercial vessels in the last 35 years.

Propeller Shaft Bearing



Thordon COMPAC is a high performance water lubricated bearing system primarily for “blue water” operating conditions. Specially formulated with a low coefficient of friction to reduce startup friction and eliminate stick-slip,

Learn More

Shaft Coating



Thordon's ThorShield propeller shaft coating system provides corrosion protection against seawater. This toughened, 2-part epoxy coating is up to nine times more flexible than existing shaft coating products.

Learn More

Water Quality Package



Thordon Water Quality Package is designed to supply seawater to the propeller shaft bearings for lubrication and cooling while condition the seawater by removing suspended solids.

Learn More

Shaft Seals

Seal installed on Hudson low res (crop)


The Thordon SeaThigor Seal is a mechanical face seal for 300mm (11.8") to 750mm (29.5") water lubricated propeller shafts found in yachts, cruise ships, merchant ships and naval vessels. The SeaThigor has evolved from a design first tested in 2003 and improved during the next decade.

Learn More


Technical Papers


Class Society Requirements For Extended Shaft Withdrawals



The final (fully finished) sizing of a Thordon elastomer or ThorPlas bearing can be determined by using the Thordon Bearing Sizing Calculation Program.

You cannot run the Thordon Bearing Sizing Calculation Program without a User Registration Number. Once you have a User Registration Number you can download the Program below and enter it when prompted.

Click here to Request a Bearing Sizing Program User Registration Number

If you have a Bearing Sizing Program User Registration Number, you can download the program here


Find My Thordon Contact

Our Newsletter

View All Recent News

  • News Thumbnails 320x160_NW23-MF

    Thordon Merchant Fleet NewsWorks 2023

    Thordon’s web-based newsletter specifically developed for marine users of oil-free and grease-free bearings in the merchant marine sector. This newsletter includes articles that highlight our successes on tankers, bulk cargo carriers, ferries, and cruise ships with COMPAC seawater-lubricated propeller shaft bearings, and ThorPlas-Blue deck equipment installed and used around the world. We also introduce Thordon’s new BlueWater Seal and highlight the largest rudder bearing Thordon has ever produced.
    Learn More

Recent Marine News

View All Recent News

  • Orkim Sapphire fitted with COMPAC

    Orkim Takes to the Water with Five Product Tankers Fitted with COMPAC

    Jul 12, 2021
    China’s Fujian Southeast Shipyard has delivered four in a series of five new product tankers ordered by Malaysia’s Orkim Sdn Bhd. The 9000dwt Orkim Sapphire and Orkim Pearl, and 14,500dwt Orkim Diamond and Orkim Emerald represent the first vessels in the ship operator’s fleet to be fitted with a COMPAC seawater lubricated shafting system from Thordon Bearings.
    Learn More
  • COSCO Vessel fitted with COMPAC bearings

    COSCO Confirms Thordon Seawater Lubrication for Eight Newbuild General Cargo Ships

    Jun 15, 2021
    COSCO Shipping Specialized Carriers, a subsidiary of China Ocean Shipping Group (COSCO), COSCO Shipping Lines, has confirmed that the eight newbuild multipurpose cargo vessels entrusted to COSCO Shipping Heavy Industry (Dalian) Co. Ltd. will each feature a COMPAC seawater lubricated shaftline arrangement from Thordon Bearings. The scope of supply, to be rolled out in two four-ship batches scheduled for August 2021 and December 2022, includes COMPAC propeller shaft bearings, shaft liners, ThorShield shaft coating, and Thordon’s Water Quality Package.
    Learn More