Drill rod demagnetizing device

The utility model relates to a demagnetizing device for a drill rod, which belongs to the technical field of coal mine equipment and comprises a transmission mechanism, two demagnetizing coils which are connected with the transmission mechanism and synchronously and relatively move at the same speed, and a controller which is electrically connected with the transmission mechanism and the demagnetizing coils, the centers of the two demagnetizing coils are located on the same horizontal line, a drill rod is horizontally inserted into an inner cavity of each demagnetizing coil, and the two demagnetizing coils are symmetrical relative to the middle of the drill rod. The demagnetizing coils symmetrically arranged in the middle of the two opposite drill rods move relatively at a constant speed in the length direction of the drill rods, bidirectional demagnetizing is conducted on the drill rods, meanwhile, the polar direction of residual magnetism on the drill rods is changed, two polar polesin the polar direction a