Patent ID: 9115555
Filing Date: 2015-08-25
Classification: E21B,H01F

Abstract:
1. A magnetic attachment mechanism for use with a downhole tool comprising: a plurality of permanent magnets having a first magnetic field; a demagnetizer comprising an electric coil configured to form an electromagnet having a second magnetic field, wherein the second magnetic field of the demagnetizer is configured to at least partially cancel the first magnetic field of the permanent magnets when the demagnetizer is in the activated state, and wherein the second magnetic field of the demagnetizer is configured to increase the first magnetic field of the permanent magnets when the demagnetizer is in the deactivated state; an actuator configured to transition the demagnetizer between the activated state and a deactivated state, or the deactivated state and the activated state; and at least one downhole tool coupled to the plurality of permanent magnets.