How does directional drilling work

Previous Next. View Larger Image. We Drill a Pilot Hole To start horizontal directional drilling , drilling fluid is pumped through a pipe and bit which creates high-pressure jets and grinding of the soil ahead of the drill. We Pre-Ream the Pilot Hole After the pilot hole is created, it is enlarged and expanded to the appropriate size for the needed utility lines. We Pull Back the Pipe Lastly, the pipe is pulled back through the pre-reamed tunnel using a drill rod and reamer attached to a swivel.

Call: or email: advanvedlinesystems boretherockies. About the Author: Advanced Line System. Related Posts. It began at the first site, Judy Way in Aston, early in The HDD process proceeds in stages. First, a relatively small pilot hole is drilled.

Finally, the pipe itself is pulled through. For the Dragonpipe, a final hole of around 30 inches will be needed for the larger of the two planned pipes 20 inches.

How do you get the drill to go where you want? When I first heard of HDD, my curiosity was aroused. How was it possible to stick a drill into the ground and have it emerge again, perhaps half a mile away, at a precise location?

How could they know where the drill was, once it was underground? And how could they change its direction if it strayed off course? The well drilling I had witnessed, growing up in the Midwest, was a simple process.

Point the drill straight down, push the spinning drill pipe downwards until the end of it was near ground level, add another length of pipe to the drill string, and repeat. The mud flowed back up the hole and emerged around the drill pipe, bringing with it bits of rock and other material the drill had penetrated. HDD, as I learned, is a refined version of that process.

Steering the drill. In order to be able to change the direction of drilling, the drill pipe cannot rotate as it does in traditional drilling. Instead, only the drill bit at the front end of the drill pipe is rotated. The drilling mud, which is constantly pumped down the pipe, is used as a source of power to turn the bit.

The speed of the pilot hole will vary upon existing soil conditions and the amount of steering which is required. Upon reaching the exit point, the beacon housing and bit is detached and replaced with a reamer. The second step is to pre-ream the pilot hole and enlarge it to a size sufficient to safely install the product lines. A reamer is pulled back and rotated while pumping drilling fluid to cut and remove solids to enlarge the hole.

Pre-reaming speeds will vary depending on existing soil conditions and the amount of cuttings that are removed from the hole. Bentonite and other additives will be used to ensure a clean and stable hole. This will help with the stability of the bore hole and with fluid loss or infiltration. The accuracy of the tool is 0. At the same time the tool is not affected by magnetic fields from for example railways and cables.

Because of our modular and state-of-the art design it is possible to add specific add-ons to the drill, like GPS track and Radar Intersect. The modules offer a solution for every situation, that make drilling projects possible that were previously unthinkable. To view this video please submit your cookies. During the first fase a drilling head that is hollow inside is pushed through the ground via a rig. Bentonite is poured into the hole from the surface. This is done to keep the borehole open.