Non-magnetic drill pipes are supporting equipment for measurement while drilling (MWD) in directional drilling. They function to reduce external interference on MWD devices, transmit signals, convey power media for downhole motors, and transfer power from drilling rigs. As a key component of underground directional drilling tools in coal mines, they feature low magnetic permeability, high tensile strength, and excellent torsional resistance. They provide a non-magnetic environment free from Earth’s magnetic interference for downhole measurement systems, ensuring that the magnetic field at the probe is almost equal to the nearby Earth’s magnetic field. This enables accurate identification of the borehole’s geomagnetic direction and guarantees the measurement accuracy of the system.

A set of non-magnetic drill pipes usually consists of an upper non-magnetic drill pipe, a probe outer pipe, and a lower non-magnetic drill pipe. The term “upper” and “lower” refers to their distance from the surface—those closer to the surface are called “upper,” and those farther are called “lower.” The probe is installed inside the probe outer pipe.

The upper end of the non-magnetic drill pipe is connected to ordinary drill pipes, and the lower end is connected to a screw drill (also known as a downhole motor).

Please refer to the following for the specific installation diagram: