Drill pipe is hollow, thick-walled piping that transmits drilling fluid and torque through the wellbore to the drill bit on a drilling rig. It is manufactured to withstand severe internal and external pressure, distortion, bending, and vibration as it both rotates and lifts the bottom hole assembly (BHA). Drill pipe is threaded on each end in a section of pipe referred to as the tool joint. It is manufactured, sampled, tested, and inspected in accordance with standard specifications such as the American Petroleum Institute (API).