When drilling like 12 km deep into the ground, how is it possible that a 12 km long pipe (drill string) is able to turn the drill bit AND be pushed down enough to drill??

Question

A 12 km long pipe seems like a ridiculous length for any of that to be possible. Isn’t it like trying to drill a hole with a 258 ft long piece of spaghetti?

In: 1335

Answer 1

It is.

Which is why they’ll typically use stabilizers (short pieces of pipe with 3 to 5 steel fins that are close to the hole diameter) on the bottom hole assembly in order to keep the drill straight.

The pipe above it will wrap and flex along the sides of the whole, but that doesn’t matter as much so long as the bottom portion of the drilling pipe is held straight.

It gets a lot more complicated once you’re doing horizontal wells, but it’s relatively straight forward to drill a well straight down with minimal deviation.