BNF Water lubricated propulsion system (Stainless steel sterntube) 

To prevent the stern tube from corrosion, our water lubricated stern tube is manufactured in stainless steel. The stern tube is executed with at least two welding sleeves, already welded onto the sterntube in our workshop. This way the stern tube can be welded into the (mild steel) boat casco easily.

Delivery of the stern tube with more / longer length welding sleeves is possible on request. Welding has to be performed with care, to prevent high welding stresses in the stern tube, causing deformation and/or bending (bearings will no longer be aligned).

The stainless steel stern tubes are executed with pre-mounted rubber bearings. The bearings have straight flutes with an optimised shape. The shape of the flute is very important; creating a water film between bearing surface and the shaft is highly dependent on this shape. All bearings are individually locked with a locking bolt, making it possible to replace if needed. When bearings are replaced the stern tube is remaining in the aligned position.

We have two options for the propeller shaft seal at the front side of the stern tube; the ‘Volvoseal’ radial seal or the ‘PSS-seal’ mechanical seal. The connection for water supply is located at the front side of the stern tube but in some cases it is located at the propeller shaft seal.

Downloads
Download the Drawing BNF water lubricated propulsion system (pdf). It can be used for a request for a quotation or to send us your purchase order directly.

---

Back to Water lubrication