a sleeve bearing is described which is useful for carrying the rotating propellor shaft of water craft , as well as for various industrial purposes . the sleeve bearing consists of a single homogeneous solid , hard elastomeric urethane polymer having a shore d hardness of at least 60 , a compressive modulus of elasticity at a 4 % compressive strain of at least 50 , 000 psi and a dry dynamic co - efficient of friction against steel of no more than 0 . 20 . this polymer is machined so as to fit within a cylindrical housing by means of a forced interference fit providing sufficient outward radial force by the outer surface of the sleeve on the housing to retain the bearing in movement - free fit during the operational life of the bearing .