Marine Bearings

 

 

 

 

Palmer Products Inc. is proud to offer the ShaftSaver™ Rotary Bearing line to the Maritime Industry, the only shaft bearing on the market that eliminates shaft wear and replacement by rotating with the shaft.  Not only does the ShaftSaver save your shaft, it can usually be retro-fitted to a worn shaft that would normally have to be scrapped, saving you down time, drydock fees, and shaft replacement costs.  Imagine not having to drop rudders and pull shafts every time you hull out, you might even forget you have shaft bearings!  

 

 The ShaftSaver was originally adapted for the high speed, high RPMs of the WWII era PT boats, reaching speeds of 50 knots with 3000 RPMs on three shafts, the conventional bearings of the day didn’t stand a chance.  Navy Engineers found that at high RPMs the shaft would ride off center toward direction of rotation, similar to the effects of prop walk during single screw maneuvering.  The reason the ShaftSaver works so well at these speeds is that the rotary bearing will compensate for a change in shaft position from 0º - 135º and not loose its efficiency.

 

 

ShaftSaver bearings also have the added benefit of reducing vibration, making for a smoother, quieter night, and a happier crew in the morning!  Along with a smoother ride, ShaftSavers are well known to increase efficiency by reducing friction usually associated with shaft/bearing interaction.  At high shaft speeds the bearing actually floats on a cushion of water, which reduces the coefficient of friction, meaning you will see higher shaft RPMs at the same power output.  At low shaft RPMs the weight of your shaft presses down on a conventional ‘cutless’ bearing, and will, over time will wear out the bottom of the bearing, that’s the shaft ‘thump’ you sometimes hear when you clutch in and out.  Because the ShaftSaver rotates with the shaft you can’t wear out the bottom!   Speaking of wear, the ShaftSaver has been proven to out last ‘traditional cutless’ bearings up to 12 times in extreme sand and silt conditions, this is due to the 360º water cushion that keeps grit suspended throughout the rotation and pushes it out though the water grooves on the topside of the wear sleeve. 

Since its inception in the 1930’s the rotary bearing has seen a few improvements, back then navy grade brass was the only option for shell material, today we offer a range of both metallic and non-metallic options.  We have also added set screws to the locking rings ensuring that no matter how often you touch bottom, your bearings will stay put!  Run of the mill nitrile rubber has given way to our unique LCF (Low Co-efficient of Friction) nitrile rubber, developed with offshore racing in mind, allowing the bearing to ‘run dry’ while skipping over the seas. 

 

These improvements, among others have made the ShaftSaver rotary bearing the clear choice when performance, efficiency, and economics are factors in your shaft bearing selection.  We offer almost every ‘traditional’ bearing size, and will be glad to set you up with the right configuration for your vessel. 

 

 As a professional mariner, I ran conventional tugs and workboats for years, and understand how vital efficiency and cost cutting is, especially to owner/operators and fleet managers.  I stand behind the ShaftSaver rotary bearing 100%.  I personally guarantee you will notice the difference the first day running ShaftSaver bearings, and you'll see the savings next hullout.

 

 

 'Whether it’s your work, or your pleasure, your boat should be running ShaftSaver™  bearings.'