Waterwrap: A 50-Year Journey That Started with an Opportunity

 

It was October of 1975 when a team of Raychem pipeliners headed south to Grand Gulf, Mississippi with a simple goal: solve a real problem in the field.

At the time, the large-diameter pipe market was struggling with a familiar challenge—how to reliably coat field joints in a way that was consistent, repeatable, and practical for crews working under tough conditions. And in those days, when Raychem identified a need, the company didn’t hesitate. They saw opportunity.

In the mid-1970s, Raychem was best known for manufacturing tubular heat-shrink sleeves for oil and gas pipelines. One of the flagship products was the TSS (Tubular Shrink Sleeve). It worked well—but only when pipe sizes and logistics allowed for a sleeve that could slide over the pipe.

Large-diameter pipe created a new challenge. You couldn’t easily slip a tubular sleeve over it in the field. So Raychem’s engineers did what they did best: they invented something new.

The result was a wrap-around heat-shrink sleeve prototype designed specifically for large pipe. And what did they call it?

LTSS — Large Tubular Shrink Sleeve
(…even though it wasn’t actually supplied as a tube).

Raychem was exceptional at innovation and rapid R&D. Naming products? Maybe not their strongest suit—but the technology was what mattered.

Armed with LTSS sleeves and a team of field technicians, Raychem went to work evaluating the new design under real-world conditions. What’s fascinating—at least to those of us who live and breathe pipeline coatings—is that this LTSS prototype was the first generation of what we now know as Waterwrap.

Over the decades, that original concept evolved dramatically:

• Improved formulations

• New backing materials

• Multiple thickness options

• Enhanced performance for demanding environments

Each improvement built on the last, refining the product into something truly special.

Waterwrap Today

Fast-forward nearly 50 years, and Waterwrap stands as the premier field joint coating for water pipelines. It’s trusted around the world for its reliability, ease of installation, and long-term performance.

Even more impressive? Waterwrap has proven itself capable in weld-after-backfill applications—one of the most demanding scenarios a field joint coating can face.

Every proven product has a beginning. For Waterwrap, that beginning was a forward-thinking team in 1975, a job site in Mississippi, and a willingness to rethink how field joints could be protected.

So here’s to 1975 Raychem—seeing a problem, seizing an opportunity, and laying the groundwork for a product that’s still protecting pipelines half a century later.

Well done.

Heat Shrink Sleeves on Water Pipe

Water Pipe and Shrink Sleeves

     Are heat shrink sleeves ever used on water pipelines?  Absolutely!  Water lines (ie: pipelines that are being constructed to carry water....) are built just as often as oil and gas lines in the USA.  Ranging in diameter from 12" up to 156", shrink sleeves are used regularly in that industry.

     Generally coated in a factory with tapes, urethanes, epoxies, Pritec, polyurethanes or coal tar enamels, water lines are going to have a field joint or a girth weld just like natural gas and oil lines do.  In the field, during pipeline construction, there is going to be a bare section of pipe right at the weld after the weld has been made.  This bare area is going to have to be coated!  You can't simply bury an uncoated pipeline!

     Shrink sleeves are used regularly here.  With decades of experience and use history in that marketplace, you really can't make a more reliable, safer choice.  Also, shrink sleeves are generally fully compatible with all of the commonly used factory applied coatings listed above.  Historically, products like WPCT or WPC100M have been used extensively there.  Now, a product like the Covalence Waterwrap is a leader.

     Waterwrap is a 2 layer field joint coating system designed for corrosion protection of buried large diameter water pipelines operating at ambient temperature.  The first layer of the WaterWrap is a visco elastic, low preheat adhesive sealant.  The second layer is a thick walled, radiation crosslinked, high density polyethylene with the permanent change indicator built into the backing.

     WaterWrap is a wrap around heat shrinkable, ready fit assembly for the corrosion protection of field girth weld joints in water distribution and transmission systems.  WaterWrap/B is compatible with standard pipe coatings WaterWrap can also be used for coating bare, replacement sections of pipe and large radius bends.  WaterWrap system-B is designed to be applied with a minimum preheat temperature and is ideal for large diameter pipe.  The installation is carried out directly on the cleaned and dried (pre-heated) pipe surface.  The use of the 939 filler is required when the step down on the weld bead is greater than or equal to 1/4".  The filler 939 is a thick mastic-like butyl rubber designed to fill and smooth transition areas.  The semi-tacky composition remains flexible and easily molded in place to conform around irregular shapes.  During installation, the heat shrinkable sleeve is wrapped around the pipe and heat is applied.  The heat activated backing contracts to form a tight fit around the joint eliminating entrapped air and filling the smallest of crevices with a high quality, corrosion inhibiting visco elastic adhesive sealant.  The permanently cross linked polyolefin outer layer forms a tough barrier against mechanical damage and moisture. 

     Water wrap contains no ashpalt - does not give off gas toxic vapors.  It is safe to use.
     Water wrap offers to permanent change indicators:  underheat indicator ensures correct application heat to entire sleeve.  Overheat indicator ensures no excess heat.  Result - reliable installation and full inspectability at any time after installation.
     High modulus of elasticity backing - greater soil stress resistance and better overall performance. 
     High impact resistance - WaterWrap is tough, but flexible throughout. 
     High shrink force - optimizes flow and fill of visco elastic adhesive sealant which offers greater long term protection.
     Low application preheat makes installation fast and easy.  Keeps installation cost low.
     No special equipment or skills required - Waterwrap is easy to install and saves time.