SETUP FOR DRILLING HOLE Russian patent published in 1997 - IPC

FIELD: drilling equipment. SUBSTANCE: this is used for drilling holes to test promising bed. Hole drilling setup has pilot drill bit, tester, safety adapter, expander, drilling tubes. Tester has body with valve located inside it and it is in the form of spool or spring-loaded lock with collet detent, and mounted on outer surface is movable piston with collet interacting with holes made in boss of body. In process of drilling pilot hole, inner passage and annular space are open for passing drilling fluid. At creation of depression upon bed, circulation of drilling fluid is stopped, and tool is slowly lifted. At this operation, inner valve is closed and piston closes holes in body boss, thus plugging annular space. Then, lifting is discontinued, time lag is effected during certain period, then drilling is continued. Reservoir fluid brought into solution is delivered to surface where it is detected by means of geochemical apparatus. EFFECT: high efficiency. 1 cl, 5 dwg