出典:Wikipedia
出典:『Wikipedia』 (2011/07/24 02:27 UTC 版)
Drill pipe, is hollow, thick-walled, steel piping that is used on drilling rigs to facilitate the drilling of a wellbore and comes in a variety of sizes, strengths, and weights but are typically 30 to 33 feet in length. They are hollow to allow drilling fluid to be pumped through them, down the hole, and back up the annulus.