مهندس بترول - TOTCO RING A Totco ring is not really a sub, but it is included here for convenience. It is a small insert that is placed inside the drill string
e Totco D392002161 MMD 001 update08 - YouTube
مهندس بترول - TOTCO RING A Totco ring is not really a sub, but it is included here for convenience. It is a small insert that is placed inside the drill string