| 摘要 |
A rotary drill bit for use in drilling or coring deep holes in subsurface formations comprises a bit body having a shank for connection to a drill string, a plurality of cutting elements mounted at the surface of the bit body, and a passage in the bit body for supplying drilling fluid to the surface of the bit body. At least some of the cutting elements are each mounted on a stud which is received in a socket in the bit body, there being provided within the socket and disposed around at least a portion of the periphery of the stud resiliently compressible retaining means, such as a corrugated sleeve, which is formed separately from the stud and bit body and is resiliently compressed between the stud and the wall of the socket so as frictionally to retain the carrier in the socket. |
