Replies to This Discussion

Permalink Reply by Les Bamburg on October 11, 2010 at 3:54

Sesport, HDD is used extensively in pipeline installation projects.

• ▶ Reply

Permalink Reply by Mac Davis on October 11, 2010 at 10:39

Is this the technology they've been using for years to go under rivers instead of doing pipeline bridges, or is it something new? I remember being fascinated as a kid 40+ years ago by the pipeline bridge over the Red River south of Shreveport, but they don't seem to do that any more.

• ▶ Reply

Permalink Reply by el paso techA1 on October 11, 2010 at 12:23

Been using it for years. Regency recently installed a 36" pipeline under Lake Bisteneau that extended over a mile. All the new pipes installed the past few years have used HDD under the Red
River.

• ▶ Reply

Permalink Reply by sesport on October 11, 2010 at 13:19

Thanks, guys. Any idea whether these kinds of lines hold up better as they age, in terms of safety & environmental concerns, than pipeline over ground? I've been reading up on one looonnnnggg (oil) pipeline project running N-S, but I can't find any info as to whether this kind of construction is being used in that particular project.

As usual, curiosity just gets the best of me, just wondering.

thanks again, 80)

• ▶ Reply

Permalink Reply by Johnnie Joe on October 11, 2010 at 14:09

Normally these use a thicker wall pipe and have an A.R.O. (Abrasion Resistant Overcoating) coating on top of the F.B.E. (Fusion Bond Epoxy) on the pipe. Since HDDs can go +100' underground, +7000' long, and will create a low spot for liquids to hang out you want them to last longer for sure since they are too costly to repair. Most times you will have a requirement that you have to use heavier wall pipe as well depending on what you are crossing(TxDOT, USACOE, UPRR, etc.). HDDs are used everywhere freely. Landmen will negotiate deals with landowners based on them for no other reason than they won't disturb their property. This is more common in urban areas. Wetlands, pipeline corridors, roads, neighborhoods, rivers, lakes, trees, you name it they drill it.

• ▶ Reply

Permalink Reply by sesport on October 11, 2010 at 16:08

Thanks, JJ. Would that be similar to the pipeline being used in the Keystone project?

80)

• ▶ Reply

Permalink Reply by Johnnie Joe on October 11, 2010 at 16:52

I would think so except the part about liquids at the bottom since the Keystone is crude oil. I'm used to doing natural gas pipelines where you can get liquids in low spots that you have to PIG out. HDDs are used for fiber optic, poly pipe, cable, anything that you can pull through a hole basically. One of the main challenges can be having a straight pullback string on pipelines since once the hole is drilled and reamed you then have to have the entire length of the HDD of pipe already welded up and on rollers so you can pull it through. You can break it into a few strings when you have to but one long one is best.

On the urban HDDs I know for a fact that here in Ft. Worth they will run below city streets as far as they can and then curve horizontally to hit a vacant lot to come out and then go right into another. You would have to have a pretty good reason to be able to block eminent domain to not open cut a pasture though. The cost of HDDs is way more than open cut. It can be risky too. You don't always have the correct geology for them to work. With gravel your drilling mud won't return, iron ore you can't see where your going, certain rock in the wrong location can keep you from steering where you want as well. It might take weeks and multiple trys and you still don't pop through. Then, if you do get through you might have your pullback string get stuck 3/4 of the way on pullback and have to leave that in the ground useless($$$$). Otherwise when the geology is right they can pop a 3,000' drill out within' a half inch of where it is supposed to come out, ream it, and pull it back before anyone has time to realize there's a pipeline 50' below em'.

Sorry I ramble but it took me awhile to gather what I know on HDDs and it was sort of hard to find a lot of info on them until I got to ask some contractors, so I don't mind sharing what I know or can learn here. Please correct me where I'm wrong.

• ▶ Reply

Permalink Reply by sesport on October 11, 2010 at 17:07

Thanks, again JJ. This is nowhere near my field of expertise, so I'll let those who are do the chiming in on that.

80)

• ▶ Reply

Permalink Reply by Dion Warr, CPL on October 12, 2010 at 10:43

Sesport:

Everything that JJ just said was true (except for the part of the iron ore, which I can't verify to be true or not because I've never worked such an area, but it makes sense).

I just finished working a pipeline install (we did ROW acquisition) with HDDs of up to 1600' while pulling dual 6" pipes. On that particular length bore, a reaction between a clay layer and prolonged contact with the drilling fluid resulted in a constriction of the borehole which seized the drilling string. The contractors had to temp. abandon the string in place, pushed a second drill string to the point of constriction, reamed the hole as much as possible, then worked (push/pull) the original string free to push the string through. Once there, they sized up the back reamer, pulling backward as the recirc'ed new drilling fluid to combat the swelling clay, and managed to finally pull it all (drill string, backreamer and pipe section).

This is where the HDD had value however: The drill allowed for the placement of these lines beneath a wetland area (thus no USACE mitigation), several active and abandoned utility crossings, newly relocated fire water and sewer lines, around and through commercial property frontage, in the middle of a road expansion project such that no manual exposures of any lines were required (time intensive), and no manpower was subjected to confined space conditions (4 feet or more below grade with limited access, which would result in additional personnel and plant protection supervision, inspection, and safety-related equipment). The process took approximately 6 days (which was longer than scheduled). The lines were placed 52 feet below grade at the road crossing, 20 feet below the deepest line (a sewer line upgrade which itself was placed by HDD), and thus should not require any relocation when the road is eventually expanded (thus paying further dividends in not costing the client for self-relocation in a designated construction corridor at a later time).

The contractor did not view this job as particularly challenging in the view of either length, pipe pull, or general congestion in the work area; they had pulled longer pipe lengths, greater diameters, multiple pipes, and worked in much more congested areas (one recent project was in "Chemical Plant Alley" in the Houston Ship Channel). Even the drill string difficulty, though unusual, did not throw them for a loop.

Though these guys were not tickled to death about pulling the pipe sections in two lengths (they welded up the pull length in two halves, which were welded together at the halfway point), their concern had more to do with the borehole status and conditioning while they waited for the welds to be completed and tested. As long as they can bore a clean hole, they would have rather pulled the entire length smooth and steady than give the borehole the time to try and close up around the pipe. Other than that, no worries.

Permalink Reply by sesport on October 13, 2010 at 11:17

Hold on, Dion, I'm assimilating that information. We virtual bookworms are like that, ya' know.

Thanks for chiming in.

lol, 80)

Permalink Reply by Mac Davis on October 11, 2010 at 14:13

I find the fact that the pipelines can be deep with this technology. You don't necessarily need to clear the surface, restrict surface usage, etc.

Got to be a bear if you need to make repairs, though.

I wonder if it will ever become common to use this instead of trenches in "normal" areas instead of rivers, environmentally sensitive areas, etc.

I wonder if it might ever become relevant to imminent domain cases. Could someone block imminent domain surface rights for a pipeline by claiming that HDD should be used instead?

• ▶ Reply

Permalink Reply by sesport on October 11, 2010 at 16:14

Mac - I wondered the same about repairs. I know it costs an arm & a leg & a first born to get in-ground home pipes repaired, so I figured it would cost even more for major transport pipeline installed in this manner.

And what JJ says about urban areas has me going "hmmmmm???" too. Your thoughts about eminent domain are food (probably donuts & coffee, lol) for thought. hmmmm???

80)

• ▶ Reply