摘要 |
<p>A device for determining the stuck point of a drill pipe in a borehole consisting of two relatively movable sections, anchoring means for each section, a sensing means for detecting relative movement of the two sections and producing an inductance representative of the movement. The inductance is transformed into a frequency modulated signal which is transmitted to the surface and converted from a non-linear direct current voltage representation of relative movement to a linear direct current voltage.</p> |