How Do You Steer a Drill Below The Earth?

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I work in the fiber optic network industry, and previously worked in the gas utility industry. We used to joke that you should always carry a length of fiber optic cable with you in case you get stuck on a deserted island. Just bury the cable and when the guy with the backhoe comes out to cut it you can just ride back with him.

That string in the gel demo was awesome and gave such a simple and precise explanation of a problem that I always wondered about. Beautiful!

I used to work for a UK drilling company as a tracker. We drilled under railway lines with mm tolerances on the tracks. Under woods that had preservation orders and under lots of domestic properties. We drilled under a river aiming for a range rod that the client had stuck in the ground. I will never forget the look on his face when we emerged from the ground and knocked the rod over. We used to say " any fool can still down. Coming back up and arriving where you want to be takes skill.

I could never have imagined how you can steer a long, flexible drill bit. After you explained it, it seems so obvious.

used to work on a directional drilling crew. very cool. we were a small company and one day we hit a big set of fiberoptic lines. poor company went bankrupt after paying for repairs on that fiber.

Here in Germany that drilling method did become more known to the public when the company "FlowTex" was sued for the (back then) most expensive large-scale fraud in Germany. The damage was roughly 4.2 billion USD. The company had 270 machines but those were sold multiple times (3142 machines had been sold). When they had investors visiting they drove to one drilling site, then had lunch and then drove to a different drilling site. During the lunch brake they moved the drills from site 1 to site 2 creating the illusion of a bigger pool of machines. (see my correction) Correction The scam worked more like that they changed the serial number plates on existing machines with new created serial number plates.

As a utility locator, The talk about the potential impacting of other underground utilities was greatly appreciated. Always call before you dig!

Thanks Grady! This answered so many questions that I didn’t even know I had. We had one of these drill right through the water supply to our house. They were like, “there isn’t a pipe here” and I was like, “well, there’s no water going into our house anymore so…” They had it all patched up in a couple days.

My hone region of ohio is known as "DD paradise" because there are 50 or so directional drilling companies based in a 20 Sq mile area. Also 4 years ago, TC Energy did a reconstruction project on the east buckeye express 36in diameter natural gas pipeline which travels underneath 3 major waterways in my region. My favorite way to kill time was to go out and watch the semi sized drilling rigs boring and pulling up to 3 miles of pre-bent thick wall pipeline on the ROW.

Having recently experienced fiberoptic cable installation in my neighborhood, I can confidently say the lack of trenching was both noted and appreciated

I worked installing fiber optic cable when I was in high school, horizontal drilling 4’ underground in residential areas. I was the guy who used a hydrovac to expose existing utilities before drilling so you didn’t hit them with the bit. I then got a degree in petroleum engineering and work in the oil and gas industry drilling horizontal wells. The concept is identical and many technologies are shared , only difference is you start going horizontal at 10,000’ instead of 4’!!

I studied geology and worked with directionally drillers at a utility contractor. Their biggest challenge the drilling foreman told me was hitting hard rock at glancing angles. The problem project that eventually had to be trenched was at the foot of the Wasatch mountains and they hit a high quartz content sedimentary layer less than 30 degrees from parallel to it and it just skipped along the outside edge of that fold and came out where they didn't want it to. They had drilled right through it at more square angles where the bit would be forced to go ahead and chew through that harder to cut rock.

I assisted an HDD on Mariner East 2, ME2. We had an inadvertent return so bad we built a pit around it and simply used it as a recirculation pit. There was a lot of effort to mitigate damage professional geologists at each drill and field techs/engineers walking the surface to look for IR's. Amazing tech

They use pulsed mud systems sometimes for locational information. We used to do maintenance on downhole tools, and one we had was a probe that was powered by a turbine spun by the mud going down the drillshaft. it sent information back to the headunit by limiting the mudflow, causing pressure pulses upstream. More useful than radio when you're 20kft or more deep. Measured all kinds of information. Radiation, vibrations, temperatures, gyro orientation, magnetic fields. All useful for figuring out where and what you're drilling through when you can't see it. Oh also tangentially related (no pun intended), the drill bits on the end, are also powered by that same mudflow. It's quite ingenious use of an already required aspect of drilling to add a power transfer through the lubrication medium. It's like if the coolant pump on your CNC mill actually powered the computer and the spindle at the same time.

The drill bit knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the drill bit from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is.

I work at an Engineering firm and have designed multiple directional drills across intercoastal waterways. I now use this video to introduce new engineers to the basics of directional drill. Thanks for putting this together. Also, I see you used to work for Freese, we are partnered with them on a project. I'm a Kimley-Horn guy.

4:50 bentonite needs hours of mixing to shear so it creates the shear-thinning fluid it needs to be able able to suspend cutting while pump is off. Posting this comment while my drilling bit is drilling at 14,000 ft below ground. I always liked the way u demonstrate concept and really liked how u showed how mud supports well walls.. one more thing is also when water infiltrate in permeable sand leaving solids on wells wall which supports it which we call filter cake. Ty for ur quality content and good presentation. Glad i found something to relate to in ur channel.

that's super interesting its also similar to how the apollo capsules were steered on reentry. The mass was off center so by rotating the capsule it could change pitch or yaw

That offset drill bit is such a simple, elegant solution. I always wondered how those worked.