Drill pipe is a steel pipe with thread at the end, which is used to connect the surface equipment of the drilling rig to the drilling and grinding equipment or the bottom hole equipment at the bottom of the drilling. Drill pipe can be divided into three categories: kelly, drill pipe and heavy drill pipe. Drill collar is located at the bottom of the drill string and is the main component of the lower drill tool assembly. Its main feature is that the wall thickness is larger, and it has greater gravity and rigidity. In order to facilitate tripping work, elevator grooves and slip grooves can be processed on the outer surface of the inner thread of the drill collar. Drill collars are generally divided into three types: spiral drill collars, non-magnetic drill collars, and integral drill collars.



