Visit our website:
Call: (936) 321-3333

Wednesday, August 7, 2013

Preventing Pipe Damage During a Bundled Directional Drill

          In today's directional drilling world, it is becoming more and more common that pipeline companies are electing to save time and money by pulling multiple pipes through a single bore hole at the same time.  Think about it; one bore and one pull instead of two or three?  There must be significant cost and time savings there.

     It does present a new wrinkle on an old challenge though.  Road bores and directional drills are and have been one of the most challenging coating scenarios dating back to the invention of boring machines.  Pipelines (and by default, their coatings) are put under an enormous amount of stress during a bore.  They are (often) bearing the weight of the pipe; subject to collisions with roots, rocks or hard soils.  They are under attack and their penetration resistance, peel resistance, shear resistance and abrasion resistance values are all put to the test.   In the world of factory applied coatings, this has led to the creation of coating systems like the plant applied Powercrete ARO (abrasion resistant overcoat) or dual layer FBE.  In the world of field joint coatings it has led to the invention of DIRAX which is absolutely unmatched in the coatings world. 

     The new wrinkle however; is:  How do you prevent the pipes in your bundle from banging into each other through out the bore; creating all kinds of damage on your factory applied coating?  This is not a simple question to answer.  Any spacers or bumpers that are used are going to be subject to the same extreme forces as the coating (as detailed above).  It isn't very hard to imagine a scenario where some kind of bumper is used (say every 20 feet along the pipes) and those bumpers are knocked loose or forced to slide down the pipe; resulting in a giant pile of bumpers about 10 feet below the beginning location of your bore!  What a nightmare that would be!  You'd end up with a couple thousand feet of pipe that is damaged before the line is even put in service!  In addition; that damage would be somewhat difficult to detect for quite a long period of time (you don't have to read very much about pipeline spills, explosions and disasters before it becomes clear that; like all corrosion prevention system: cathodic protection is often flawed; broken and/or poorly designed).

     So the question is there.  How do I secure the ~1" thick bumpers to my boring bundle to make sure they stay in place and prevent my 10" line from beating the hell out of my 12" line?  Duct tape isn't going to work.  Cold applied tape isn't going to work.  No "standard" adhesive or coating is going to work.  In order for something to be successful, it is going to have to have been specifically designed to withstand the forces of a road bore.  In this case, the forces will be even GREATER as this product will have a high profile that sticks 1" off of the pipeline!!  Talk about a tall order.

     Terrifying isn't it?  Have no fear:  DIRAX is hear.  It has been used for just this type of application.  Just the other day; talking with an experienced pipeliner who has been on the job for many years - he called to get "some more of that DIRAX, that stuff is phenomenal."  So, use DIRAX to keep your bumpers / spacers in place.  It works.  It is designed for it.  Your pipe is just too expensive to trust it to anything else.  Aside from all of that; you don't want to end up saving all of that money on a bundled road bore - just to piss it away on CP system expansion and ultimately: pipeline repairs!  Just use DIRAX to hold your bumpers in place.

1 comment:

  1. Hi. In your Bundled Directional Drill w/ BBS Bumper System video on youtube can you tell me how far was the crossing? How long can you pull 4 x 16 inch pipes for?