DIRAX Shrink Sleeves for Road Bore Pipe
DIREX / DIRAX
I think it has been well established that pipe that is involved in a road bore is just about the 'scariest' pipe there is. Here you have both a factory applied coating - and a field joint coating - that are installed and inspected, and then we wave goodbye to that section of pipe as it is dragged down into a deep hole and never seen again. Sure, that pipe will have an inspection pig go through it. Sure, that pipe will be covered by some kind of a CP system (and it will be possible to detect current load increases if a corrosion problem occurs), but really - once that pipe leaves the sunshine and enters the darkness; you are pretty much depending on those coatings to survive and do their job throughout the life of the pipeline. If they are damaged during the bore; you won't know until it is far,
far too late. That's why you pay for expensive pipe coatings like
Powercrete on top of FBE or dual layer FBE. That's why you should consider a product like DIRAX for your field joints.
DIRAX is installed on top of our S1301M epoxy primer. The epoxy has been specially formulated to bond both physically and chemically to the adhesive of the DIRAX shrink sleeve system. It works. When fully (and freely) recovered; the backing of the DIRAX is 2.3mm thick. That includes a layer of fiber mesh woven between two layers of polyethylene (fiber reinforced is kind of a big deal). DIRAX is sold as a kit, which includes the shrink sleeve for coating the field joint (in a 12", 17" or 24" width); S1301M Epoxy and a 3" wide leader strip.
Now getting back to where we started...the DIRAX is installed on the field joint and it needs to be wide enough to coat all bare steel and overlap onto the factory applied ARO by at least two inches per side. In many cases, this can use the 12" wide sleeve - but some users....some users who know how scary it is that a coating cannot truly be inspected after being involved in a road bore -- those users who believe that using the best possible coating is important enough to spend a little extra - those users typically use a 24" wide DIRAX. They know that a few extra dollars on the front end of a pipeline project -- in order to avoid the incredibly costly replacements, spills, corrosion problems and damage - is well worth it (not to mention that you can't put a price tag on restful sleep at night!). People who want the best use DIRAX. People who are want to take their absolute best shot at coating that field joint in the best possible manor - use DIRAX in a 24" width. *
*Let me be 100% clear and forthcoming. I know from experience that 12" wide and 17" wide DIRAX sleeves do exactly what they are supposed to do. I know that they survive the bore without damage and without being displaced. I know that they continue to offer corrosion protection to those field joints for the life of the pipeline. I know it because it has been done -- thousands of times -- and the number of problems I've heard about is exactly ZERO. Some people just like to be extra cautious - they want to be able to look back someday and say "I did EVERY POSSIBLE THING I COULD HAVE" - and there is nothing wrong with that. It's natural in many cases. Why do people wear a belt AND suspenders? Why do cars have seat belts AND air bags? Why do my jeans have a button AND a zipper (what ever happened to button fly jeans anyway?) Why do we have a lock, and a dead lock, and a chain, and a security system on our homes? Because being certain carries great value with it.
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| This is the DIRAX shrink sleeve as supplied. As it is shrunk, it looks even more like alligator skin and is just as tough! |
Now getting back to where we started...the DIRAX is installed on the field joint and it needs to be wide enough to coat all bare steel and overlap onto the factory applied ARO by at least two inches per side. In many cases, this can use the 12" wide sleeve - but some users....some users who know how scary it is that a coating cannot truly be inspected after being involved in a road bore -- those users who believe that using the best possible coating is important enough to spend a little extra - those users typically use a 24" wide DIRAX. They know that a few extra dollars on the front end of a pipeline project -- in order to avoid the incredibly costly replacements, spills, corrosion problems and damage - is well worth it (not to mention that you can't put a price tag on restful sleep at night!). People who want the best use DIRAX. People who are want to take their absolute best shot at coating that field joint in the best possible manor - use DIRAX in a 24" width. *
*Let me be 100% clear and forthcoming. I know from experience that 12" wide and 17" wide DIRAX sleeves do exactly what they are supposed to do. I know that they survive the bore without damage and without being displaced. I know that they continue to offer corrosion protection to those field joints for the life of the pipeline. I know it because it has been done -- thousands of times -- and the number of problems I've heard about is exactly ZERO. Some people just like to be extra cautious - they want to be able to look back someday and say "I did EVERY POSSIBLE THING I COULD HAVE" - and there is nothing wrong with that. It's natural in many cases. Why do people wear a belt AND suspenders? Why do cars have seat belts AND air bags? Why do my jeans have a button AND a zipper (what ever happened to button fly jeans anyway?) Why do we have a lock, and a dead lock, and a chain, and a security system on our homes? Because being certain carries great value with it.
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