Borehole surveying appts. - has groups of centering and measuring bolts on container circumference, which are extended telescopically by electric and hydraulic drives

摘要

The appts. (1) a television camera (6), a compass (5) and an inclinometer (4) accommodated within a container (3). The container is supported in the borehole by a cable (9) through which power passes to the instruments and through which measurement signals are passed. Centering bolts (14, 15, 16, 14', 15', 16') and measuring bolts (21) are provided on the container. The bolts (1) are radially extended by electric motors and rack and pinion (17, 18). The measuring bolts (21) are extended radially by hydraulic drive.