摘要 |
In various embodiments, apparatus and methods of operating the apparatus are provided to determine existence and location of parasitic stress threes on a rod portion, the rod portion made of a magnetostrictive material and having a hollow tube. The apparatus may include a device comprising an envelope made of a non-magnetic material, a magnetic field source disposed inside the envelope, a motor to set the magnetic field source in rotational motion on the inside of the envelope, and a sensor to measure a value of the magnetic field and to deliver a signal representative of the value of the magnetic field. Operation of the apparatus may include penetration of the envelope into a portion of the hollow tube of the rod portion and translation of the envelope along the portion of the hollow tube. Additional apparatus, systems, and methods are disclosed. |