.~ Bit with leading portion (e.g., pilot) forming smaller diameter initial bore {6}
387
.~.~ Leading portion is core forming type
DEFINITION
Classification: 175/387
(under subclass 385) Apparatus in which the leading or pilot portion has a cutter element or cutting edge so arranged that the bit makes an annular cut in the formation, leaving a
central undisturbed portion of the formation in the form of a cylinder.
SEE OR SEARCH THIS CLASS, SUBCLASS:
403+, and the search there noted for other core forming type bits.
