Pipeline Repair - Case Study

    

How many 'near miss' pipeline catastrophes occur each year?

     Last week, there was very nearly another major pipeline disaster in the southeastern United States.  Under ground, a high pressure, natural gas line has been in service for many years.  This pipeline is coated with coal tar (paper and all) and is doing exactly what it was designed to do.  If we're being honest, this line is doing more than it was ever asked to do; as the coatings applied 30+ years ago have prevented corrosion better and longer than the original engineers required them to! (Click HERE if you're interested in reading an article summarizing Coal Tar as a pipeline coating).

     In any case, this pipeline was quietly doing its job when WHAM.  A construction crew laying a new pipeline in the area accidentally gouged the side of the pipe; significantly damaging sections of the coal tar and (in a few cases) causing bare steel to be exposed.  My understanding is that there was no meaningful damage to the pipe wall itself.  Isn't that incredible all on its own?  A pipeline coating that was 1/4 of an inch thick (or there about) was completely scraped from the pipe in some cases; but the pipe itself was undamaged.  I've heard football described as "a game of inches" many times; but in this particular case 'Life' was a game of inches; as who could predict what might have happened if the back hoe had struck the pipe hard enough to cause a break in the steel; a spark; a disaster.  I imagine the crew was wide eyed when they realized what had almost just happened.

     All of this resulted in a fairly common phone call to us at Joint Specialists.  On the line was a man in the field; he had a representative from the gas company on the line as well.  The question was "I've got significant damage to an active natural gas line - what do I need to do to repair this coating?" 

     I walked them through the options (as discussed here) and we quickly came up with a custom solution and application procedure for getting the pipeline coating back intact as quickly, easily and reliably as possible.  Crisis averted.  Pipeline service not interrupted and hopefully the end user will get another 25 years out of that coal tar coated pipeline!