WPCT for Road Bores?

Standard Shrink Sleeves on Road Bore Applications

     The world of pipeline coatings is much like the world of tools. Different tools are designed for different functions.  Brooms are great, and very effective when sweeping up dirt....but they are going to be pretty much useless if you're trying to cut down a tree.  Likewise an axe is great for cutting down a tree, but is not going to be particularly effective for tightening a bolt.  A wrench can tighten a bolt great, but it isn't going to be very effective if you're trying to dig a deep hole.  Likewise; standard shrink sleeves are great for basic, drop the pipe in a ditch and backfill it types of applications; but they are quite simply:  not designed for use in road bore applications. 

     WPCT is our most commonly sold ambient temperature, wrap around, heat shrink sleeve for corrosion prevention.  It is a fantastic product.  It has successfully prevented corrosion for decades on literally millions of field joints over the last decade.  It is easy to install.  It is reliable.  It essentially inspects itself.  But WPCT is not approved or recommended for use on road bore applications.  That simply isn't what it is designed for. 

     The product that is specifically designed for road bore service is our DIRAX product.  Incredible peel and shear resistance.  Unparalleled abrasion resistance and penetration resistance.  This sleeve is three times thicker than the WPCT product (on the leading edge of the coating).  DIRAX uses a two part epoxy as the primary corrosion coating.  That two part epoxy brings with it excellent cathodic disbondment resistance and improves the physical characteristics of the system (better peel / shear).  The DIRAX sleeve is then installed over the wet epoxy.  DIRAX is comprised of a three layer backing system and a high shear polyamide adhesive; which is designed to physically and chemically bond to the two part epoxy; forging a contiguous, bonded, thick field joint coating system that will easily withstand any forces it is put through during the boring process. 

     To sum up:

DIRAX for directional drilling:  GOOD

WPCT for directional drilling:  Not Good

    
     Now, there are folks out in the world who will tell you that "WPCT will do just fine on a road bore."  Please, do not believe those folks.  They are just looking to make a quick and easy sale.  They aren't evil people, they are simply uneducated.  They want things quick and easy rather than spending the time to learn the ins and the outs of the Covalence heat shrinkable products product line. 

Wrap Around Shrink Sleeves vs Road Bore Shrink Sleeves

Standard Shrink Sleeves vs Directional Drilling Shrink Sleeves

     Common question:  why can't I just use normal wrap around shrink sleeves for my road bores?

     The simple answer is:  standard shrink sleeves are not designed to withstand the incredible stresses that a road bore or directional drill puts a coating through.

     So what is the difference?  Let's talk about it.

     WPCT is our standard wrap around shrink sleeve.  It is a two layer sleeve incorporating a radiation cross linked polyolefin backing and an aggressive mastic sealant.  It has been used for decades successfully and does an excellent job when installed on pipelines that will operate at ambient temperatures and be either buried underground or installed subsea.  Though WPCT exhibits soil stress resistance levels that are sufficient for all standard pipe movement and backfill scenarios; it is not designed to withstand the soil stresses, penetration, abrasion and shear attacks that a coating involved in a road bore will see.  Would it work?  Possibly; but it isn't designed for that scenario and we can't give our stamp of approval to such an application.

     DIRAX on the other hand is our product specifically designed to withstand the incredibly difficult conditions of a road bore or directional drill.  Utilizing a two part epoxy bonding agent, a high shear hot melt adhesive and a multi layer sleeve backing (including a fiber mesh to add superior penetration and abrasion resistance), DIRAX is made for this application.

     Using a WPCT sleeve on a road bore would be like taking a Honda Accord through an extensive offroad driving course.  It might make it through -- but wouldn't it make a lot more sense to drive a Jeep or a Range Rover?