Patent ID: 8844656
Filing Date: 2014-09-30
Classification: E21B,F16J

Abstract:
1. An earth bit, comprising: a lug; a cutting cone carried by the lug; and a seal assembly which forms a dynamic seal with a radial interstice lug surface of the lug, the seal assembly including a rigid sealing ring having lengthened and shortened arm portions and a separate elastomeric sealing ring, wherein the shortened arm portion is positioned between the elastomeric sealing ring and an axial interstice lug surface of the lug, the rigid sealing ring having a space between the shortened arm portion and the axial interstice lug face wherein the shortened arm portion does not form a seal, and the lengthened arm portion engages the radial interstice lug surface and the elastomeric sealing ring energizes the lengthened arm portion against the radial interstice lug surface, and wherein the shortened arm portion includes an end surface exposed to a radial interstice cone surface.