(under subclass 57) Processes comprising drilling or forming a borehole in which the axis of the borehole is (1) curved or arcuate, (2) two straight line portions intersecting at an angle or (3) a straight line portion and a curved portion.
(1) Note. Processes of reaming or enlarging the diameter of a borehole or cutting slots longitudinally of the borehole are not included.
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4, for process and devices involving driving a core receiver into the earth formation usually in a lateral direction by an explosion.
73+, for apparatus having means traveling with a tool to constrain it to bore along a curved path.
77, for side wall sampling tool fed laterally without rotation from inaccessible hole. 78, for means carried by housing insertable in inaccessible hole to advance side wall tool laterally.
79+, for tool shaft advanced relative to guide insertable in inaccessible hole to change direction of advance.
231, for means movable relative to tool below ground to control eccentric fluid emission.
