Magnetic Single Shot Survey Tool Instrument
The magnetic single shot survey tool instrument was first used in the 1930s for measuring the inclination and direction of a well. Here we shall explain its mechanism and components.

Application

Single-Shot surveys, which photograph the instrument at a single position, are often used by the directional driller to track the drilling bit’s progress while drilling is underway. The compass unit of a magnetic survey instrument is placed in a non-magnetic drill collar (NMDC)
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