Conduits for feeding air to small bearings of journal area of rotary drill bit

A method for operating a rotary drill bit including a cone rotatably supported on a leg, the method comprising:

• rotating the cone relative to a journal area of the leg;
• supplying air from an air compressor to a primary conduit within the leg;
• supplying air from the primary conduit to a first journal conduit and a second journal conduit within the leg;
• cooling at least part of the journal area with air from the first journal conduit;
• and
• cooling at least part of the journal area with air from the second journal conduit,
• wherein a ratio of a cross-sectional diameter of the first journal conduit to a cross-sectional diameter of the second journal conduit is in a range of about 1 to about 1.4.

A drilling system comprising:

• a drilling machine comprising an air compressor;
• a drill string extending from the drilling machine;
• and
• a rotary drill bit connected to an end of the drill string and receiving air from the air compressor via the drill string, the rotary drill bit comprising:
• a plurality of legs each comprising:
• a journal area configured to rotatably support a cone;
• a primary conduit extending internally within the leg and configured to receive air from the air compressor;
• a first journal conduit downstream from the primary conduit and extending to a first air orifice of the journal area;
• and
• a second journal conduit downstream from the primary conduit and extending to a second air orifice of the journal area,
• wherein a ratio of a cross-sectional diameter of the first journal conduit to a cross-sectional diameter of the second journal conduit is in a range of about 1 to about 1.4.