Function of Non-Magnetic Drill Collars

Since all magnetic measuring instruments sense the Earth's magnetic field in the wellbore when measuring its direction, a non-magnetic environment is required. However, during drilling, drill strings often possess magnetism and magnetic fields, affecting magnetic measuring instruments and preventing the acquisition of accurate wellbore trajectory measurement data. Non-magnetic drill collars can achieve a non-magnetic environment while retaining the characteristics of drill collars used in drilling. A significant number of non-magnetic drill collar products were included in the API standard in 1990.