Abstract: An apparatus that includes one or more flow channels and method for fabricating such flow channels. The apparatus includes a body and one or more blades extending from one end of the body. Each blade includes a leading section, a trailing section, a face section extending from one end of the leading section to an end of the trailing section, and at least one flow channel extending from the leading edge section to the trailing edge section.

Abstract: An earth boring bit having a body, pressure compensating lubricating system and cantilevered bearing shaft with an annular seal surface and a radial seal surface. A cutter is rotatably secured to the bearing shaft, with an annular seal recess having radial and cylindrical seal surfaces to oppose the seal surfaces on the body and bearing shaft to define a seal gland. A resilient and annular packing ring is compressed between the cylindrical seal surfaces, but has a length less than the minimum length of the gland. A shroud extends inwardly near the outer backface a selected distance behind the packing ring to bias it inwardly. The shroud extends inwardly toward the bearing not more than about 30% of the cross-sectional thickness of the O-ring in the relaxed condition. The O-ring is compressed in a range of about 10 to 15 percent.