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??

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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?

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38 Answers

Anonymous 0 Comments

Mud motors are a thing. They rotate on the end on a drill string (pipe). The fluid that is pumped down hole (mud) to clean it out is used to turn a turbine of sorts in the mud motor or “drill bit” but this is mostly used to provide directional drilling. That being said, the drill isn’t actively “pushed” the pipes are put together such that gravity provides the “pushing” force. You put heavier pipe at the beginning to provide more weight after a while you end up with kilometers of heavy steel pipe that provides all the weight you need. The fluid “mud” l, is pumped into the center of the pipe all the way to the bottom and back up again. You track your torque and such and adjust your fluid to ensure the tailings “dirt,rock etc” makes it back to the surface and doesn’t bind everything up down hole. The drill rigs I worked on were “table drive”, the pipe would pass through the floor of the rig and interface with the table and be rotated by either big diesel motors or diesel electric set ups.

Anonymous 0 Comments

Mud motors are a thing. They rotate on the end on a drill string (pipe). The fluid that is pumped down hole (mud) to clean it out is used to turn a turbine of sorts in the mud motor or “drill bit” but this is mostly used to provide directional drilling. That being said, the drill isn’t actively “pushed” the pipes are put together such that gravity provides the “pushing” force. You put heavier pipe at the beginning to provide more weight after a while you end up with kilometers of heavy steel pipe that provides all the weight you need. The fluid “mud” l, is pumped into the center of the pipe all the way to the bottom and back up again. You track your torque and such and adjust your fluid to ensure the tailings “dirt,rock etc” makes it back to the surface and doesn’t bind everything up down hole. The drill rigs I worked on were “table drive”, the pipe would pass through the floor of the rig and interface with the table and be rotated by either big diesel motors or diesel electric set ups.

Anonymous 0 Comments

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Anonymous 0 Comments

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Anonymous 0 Comments

It works like a basic hand drill. Except driven by gigantic motors instead of hand.

The drill is rotated while being pushed down, both by gravity and machine. It is a relatively slow process. This causes a hole to form and the material drilled to be moved up along the shaft. As it gets deeper, sections of pipe/tubing are added.

Typically for wells, this is done with a specialized fluid for lubrication and to help bring the debris drilled up to the surface. The fluid is often called mud. The mud slurry is pumped down and filtered when it comes back up with drilled material.

A casing is pushed down along the sides of the well to maintain its structure and prevent contamination in and out of the well bore hole.

Then a pump system is installed and production begins.

Anonymous 0 Comments

It works like a basic hand drill. Except driven by gigantic motors instead of hand.

The drill is rotated while being pushed down, both by gravity and machine. It is a relatively slow process. This causes a hole to form and the material drilled to be moved up along the shaft. As it gets deeper, sections of pipe/tubing are added.

Typically for wells, this is done with a specialized fluid for lubrication and to help bring the debris drilled up to the surface. The fluid is often called mud. The mud slurry is pumped down and filtered when it comes back up with drilled material.

A casing is pushed down along the sides of the well to maintain its structure and prevent contamination in and out of the well bore hole.

Then a pump system is installed and production begins.

Anonymous 0 Comments

A traditional drilling rig has no ability to push, and the first joint of pipe or two will be special, super heavy weighted stuff called drill collars.

The rig is used to pull up on the pipe, and as the hole gets deep this pulling force can be a hundred tons. That leaves just a little weight on the bit, just enough to do it’s job.

Yes, the pipe is like a wet noodle, and spinning the top takes just a bit to make it to the bottom, winding up the pipe. Same happens when the rig lifts the pipe, it stretches.

Anonymous 0 Comments

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.

Anonymous 0 Comments

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.

Anonymous 0 Comments

You actually don’t push down on the bit at all. You suspend the weight of the drill string, except for a few thousand pounds. For example, if your string weighs 500,000 lbs the draw works might be holding 480,000. Every bit/motor/rock type has an ideal “weight on bit”. Otherwise you would become incredibly stuck as the pipe, which you accurately describe as behaving as spaghetti, would be shoved into the sides of the borehole.