Modern Fibre Optics Installation & Distribution Method?.

Thread Starter

MaxHeadRoom

Joined Jul 18, 2013
28,617
My local Internet provider is in the process of installing fibre optic sourced internet to all its customers.
I am watching them from my home office and am intrigued as to how they install the cable underground with minimum disturbance?
i.e. NO trenches.
A series of ~ 4ft deep holes are created in each property every so many 600 - 1000 ft, using high pressure water and the soil is sucked out of the pit into a specialized storage truck.
Then the cable or pipe is fed underground and ends up in each distant hole, one of the team follows the underground progress with a metal detector, they hit the next hole dead-on.
What process is used to install these underground with such accuracy?
 

Tonyr1084

Joined Sep 24, 2015
7,852
First - I DON'T KNOW! However, my time in the oilfield tooling arena I learned that a single off shore oil rig can drill up to 300 wells without having to move the rig. It's done by jetting at the end of the drill string. Electronics inside the drill string signal back to the driller what angle in two axis' and what direction via magnetometer the drill is facing. By rotating the string some number of degrees the driller can point the jet, which isn't straight out but rather off to one side by some angle I don't know, and literally make a hole for the drill to follow. A single drill string can be steered into an exact location by knowing these angles and how many pieces of pipe has gone down hole. I'm GUESSING they probably do something similar, jetting to a slight angle out of the end of the string to control direction and depth to end up where they are shooting.

Again, I don't KNOW this - I suspect this or something very much like it is how they accomplish that.
 

eetech00

Joined Jun 8, 2013
3,858
My local Internet provider is in the process of installing fibre optic sourced internet to all its customers.
I am watching them from my home office and am intrigued as to how they install the cable underground with minimum disturbance?
i.e. NO trenches.
A series of ~ 4ft deep holes are created in each property every so many 600 - 1000 ft, using high pressure water and the soil is sucked out of the pit into a specialized storage truck.
Then the cable or pipe is fed underground and ends up in each distant hole, one of the team follows the underground progress with a metal detector, they hit the next hole dead-on.
What process is used to install these underground with such accuracy?
mine was done with a similar process and it fascinated me as well. It was terminated in my garage with an ONT.
 

MisterBill2

Joined Jan 23, 2018
18,174
I have just watched a new gas main and branches to houses installed that way. The machine is a mechanical marvel, and the steering scheme is very impressive, And while that device used to track it looks likea metal detector, it is much more than that. At the head of the pipe is an active transponder that sends out a signal that the above ground device receives. And that device appears to be linked back to the boring machine. The3 end moving thru the ground has an angled plate so that it can steer up/down and left right, depending on which way it is positioned while pushing it thru the soil. And the transponder knows which way it is turned all the time. So the system knows what angle to turn to to steer in the required direction. It is a simple concept but the system is a mechanical marvel.
 

nsaspook

Joined Aug 27, 2009
13,081
I watched them try this near my house a few years ago. Just below the surface are massive boulders from the formation of the Columbia Gorge that make this method almost impossible for the boring head. After they hit my buried utility wires causing a power outage they did it the old fashioned way by tearing up the street to run fiber.
 

MisterBill2

Joined Jan 23, 2018
18,174
Sure would be handy to have an internationally recognized hand signal for "stop advancing the subterranean auger" because apparently waving an empty CD case at the operator 1/4 mi away doesn't get the point across.
The crew that did the work on my street were the most safety concerned group I have ever seen. As the drill advanced a worker followed it with his detector and marked the path every few feet with spray paint. AND there was constant radio communication when needed.
Part of that is probably because several years ago a crew damaged a residential line, the gas leaked into the basement of a house and exploded. One house was totally obliterated, two others were destroyed, and one person was very killed, with others being wounded. So the lesson was learned and that mistake will not ever have a chance to happen again. The guy advancing the drill knows within inches of where it is, and is in very good communication with the guy following the drill and giving the instructions for steering. In fact, I think that there is a display showing exactly where it is relative to the desired path.
 

SamR

Joined Mar 19, 2019
5,031
They use a guided cable thingy here to run cables under the pavement. It sometimes leaves a bit of a bump if too shallow. Some kind of guided miniature tunneler. Everything but power is buried here usually with a one pass specialized Ditch Witch that carries and inserts the spooled cable as it opens and closes the narrow slit. It uses what looks like a big chain saw bar but with a wider chain to dig the trench. Both phone and fiber for data and TV. Our counties private phone company is supposed to be the first with all buried service going back before the 50’s.
 
Last edited:

BillB3857

Joined Feb 28, 2009
2,570
When cable TV runs in our area were made several years ago, the installing company also used Ditch Witch equipment. One of the runs was about 10' inside the fence line of our back yard. I was lucky enough to be close enough to both see and hear the operators. Their commands were words such as, SPIN 10, PUSH 270, SPIN 5, ETC. The SPIN command was to move forward and the number represented the distance. The PUSH command was a little more complicated. The number following PUSH command represented the angle the shovel shaped end was to be positioned which controlled UP, DOWN, LEFT and RIGHT. The PUSH distance and depth was monitored by the wand being waved over the top of the ground. It was amazing to watch and see how direction, depth and overall accuracy was easily controlled.
 

MisterBill2

Joined Jan 23, 2018
18,174
It was quite impressive to see the safety protocols in action. Of course, they were working with an active, pressurized , gas main. They wound up having to replace a section about 500 feet long, because the steel gas main had developed a lengthwise split at one point. The new main was run beneath the sidewalk, which had very recently been updated by replacing many segments. So sections less than a month old had to be broken up and eventually replaced. Such a waste. If the city management had waited a month it would not have happened that way. (Sorry to bore folks with my off-topic rant, nobody in government listens to me.)
 
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