A cable company is running fiber into our neighborhood.?ÿ They are using something I?ÿ hadn't seen before. An air-driven box about the size of a small car's rear differential sits at a pothole and goes thud-thud-thud, apparently driving a probe to the next pothole maybe 10-15 yards away. I didn't see any provision for steering it or anyone tracking it, but didn't watch for long. Anybody know how it is guided?
Sounds like a mighty mole. Guided by the start of the hole and operator's luck from what I've seen.
Might be similar to the equipment used to start on one side of a river, go down at some angle to go below the river bed, then come back up at some angle to arrive at a pre-determined spot on the other side.
Seems like the river job would require the directional drilling equipment where the operator can guide in any direction and there is a transponder in the head that a locator can follow. The big name around here is Vermeer.
A cousin's son is a field engineer for Vermeer, but I've never had detailed discussion of them with him. Learned more from watching a crew in our neighborhood.
It is amazing what they can do with those rigs. But, it has to be based on real-world information. How they get that data, I don't know.
I watched a few years ago while they used directional drilling to run new power lines through our back yard.
The drill string is made of linked shafts, and the machine can add them as needed. They are always rotating except for when a guidance correction is needed. The rotation and forward thrust makes it advance in nearly a straight line.
The guy with the locator follows the transponder head and steers by calling for the machine operator to stop rotating with the drill head at a requested angle. The drill string is pushed forward and the wedge shape on the head pushes it up, down, left, or right depending on the rotary position.
When they get to the next pothole, they attach a rope or cable and pull it all back.
A job I was close to had the first pothole a few hundred feet from the high bank of the river. They were to drop roughly 55 feet to pass about 15 feet below the bottom of the river, which was flowing about 15 feet deep at the time. The end pothole was over a quarter mile distant and probably about 20 feet lower than the starting pothole.
As somebody said, it's a mole and they line it up just like a contractor lines up a pipe laser. I have a Plumber friend who has a similar set up to install new sewer laterals without opening a trench across the yard,
It looks like a scaled down bore and jack operation.
