API Oil Drill Pipe Standard: API 5D Size: 60.3 ~ 168.3mm Grade: E75,X95,G105,S135 Application: Drill Pipe Drill pipes are steel tubes with threaded ends that are used to connect a drill rig’s surface equipment with its drilling equipment, or bottomhole assembly, at the bottom of a well. They are used to transport drilling fluid to drill bits, and to raise, lower and rotate the bottomhole assembly ...