Methods and apparatus for maintaining lubrication of rolling cone cutters
mounted on journal pins. Embodiments comprise a rotating cone disposed on
a journal pin and forming a journal gap there between. A cylindrical
journal sleeve is disposed in the journal gap. The journal sleeve has a
longitudinal gap forming opposing end portions, which are continuously
contoured. A lubrication port is disposed in the journal pin and in fluid
communication with a lubrication supply. The lubrication port has an
outlet located in a recess in the journal gap. Each end of the recess
comprises a transitioning surface extending between the bottom of the
recess and the outer surface of the journal pin to prevent sharp
transitions. In certain embodiments, the journal pin may comprise two or
more lubrication ports, each located in a recess with transitioning
surfaces.