Matching Pairs Drilling RigOnline version Parts of drilling rig by Tatiana Yaikina 1 kelly 2 travelling block 3 mud pit 4 derrick 5 rotary drive 6 crown block 7 draw works A large structure standing on four legs and reaching the crown block. A machine used to impart rotational power to the drill string. A steel frame with wheels which moves up or down in the derrick A steel frame on beams at the top of the derrick. A hoisting mechanism which raises or lowers the drill pipe and drill bit. Steel tank used as a mud collector. A steel pipe, located at the top of drill string.