Seal arrangement with improved shaft bushing for a rotating ship propeller shaft

A seal arrangement for sealing around a rotatable propeller shaft of a watercraft between an exterior side and an interior side, comprising:

• a shaft bushing that is arranged coaxially around said propeller shaft and that extends along said propeller shaft from said interior side to said exterior side;
• a stationary support that is arranged coaxially around said shaft bushing with an annular gap therebetween;
• and
• at least one seal ring that is carried by said stationary support and that extends and seals around said shaft bushing in said annular gap between said stationary support and said shaft bushing;
• wherein:
• said shaft bushing comprises an inner bushing part that is made of a first material, and an outer bushing part that is arranged coaxially around said inner bushing part and that is made of a second material different from said first material;
• said first material has a higher thermal conductivity than said second material;
• said second material has a higher wear resistance than said first material;
• a ratio of a second wall thickness of said outer bushing part relative to a first wall thickness of said inner bushing part is in a range from 1:10 to 1:3;
• said inner bushing part comprises an annular cylindrical inner bushing sleeve that has said first wall thickness, and that has a radially outer cylindrical surface thereof extending axially along an entire axial length of said shaft bushing to a distal axial end of said shaft bushing on said exterior side;
• said outer bushing part comprises an annular cylindrical outer bushing sleeve that has said second wall thickness and that extends axially along said radially outer cylindrical surface of said annular cylindrical inner bushing sleeve to said distal axial end of said shaft bushing on said exterior side, and a flange part protruding radially outwardly from said annular cylindrical outer bushing sleeve on said exterior side, side;
• and
• said flange part of said outer bushing part is connected to a propeller hub.