Magnetic single shot inclinometer

摘要

An apparatus and method for preventing damage to the mechanical components of a borehole inclinometer is disclosed. The inclinometer uses a freely suspended pendulum to align with the vertical at a selected position in the borehole. A compass connected to the pendulum rotates to an orientation defined by the earth's magnetic field. To protect the components which suspend the pendulum, the pendulum is clamped between a timer and a lens as the inclinometer is lowered into the borehole. At a selected time, the pendulum is unclamped and is permitted to reach an equilibrium, measuring position. After a selected interval, the timer urges the pendulum against the lens to clamp the pendulum. The inclinometer is raised from the wellbore, and the orientation of the pendulum relative to the lens is observed to determine the azimuth and inclination of the borehole.