The Steamboating Forum

Ahoihoi,

Considering, that all the forward push stemming from the propeller has to be distributed into the hull, I was wondering how that is done. From the mechanical POV, I always thought there must be some kind of axial bearing if there are significant longitudinal forces to handle. But I see lot's of launches having only the ball bearings or flange bearings.

So, all the axial thrust is caught by these radial engine bearings without any axial bearing?

Some use purpose-built thrust bearings pre-manufactured like Dodge or others that are mounted to the hull, some have thrust bearings built into their engines. Some are the conventional collar type while others I've seen are opposing tapered roller bearings.

For our steam boats, rule of thumb is that a pillow block bearing will handle any thrust loads from a prop that fits on that diameter shaft.

Engines w/ journal bearings w/o integral thrust bearings (or pillow blocks ) should have a pillow or flange bearing to handle the thrust.

- Bart

Ah, I see. Thanks.