Waterwrap: Weld after backfill sleeve

 Coating CHALLENGE: Covalence Waterwrap (Weld After Backfill)

Today we’re taking a look at Covalence Waterwrap – Weld After Backfill (WAB), a product designed for one of the most demanding coating applications you’ll ever encounter.

Let’s start with the baseline challenge.

You’re dealing with massive, heavy pipe. It’s already in the ground. Preheating a pipe with that much thermal mass is no small task. Installation crews have to be absolutely disciplined—every square inch of the sleeve must be properly heated to ensure a reliable bond. None of this is easy on a good day.

Now add this twist:
the pipe is going to be welded after the sleeve has been installed.

Yeah… kind of nuts.

Don’t let the photo above fool you (I borrowed it from tomorrow’s history post, which goes all the way back to 1975). What’s interesting about that image isn’t just what you see—it’s what it represents.

The product shown, LTSS, was literally Raychem’s first serious attempt at developing a solution for large-diameter water lines. It was an important starting point, but very much a first pass.

Fast forward to today.

Waterwrap WAB is the result of dozens of generations of product evolution, refined over decades. Each iteration has been driven by real-world field experience—improving long-term performance on the pipe while simultaneously making life easier for installation crews. Better materials. Better installation tolerance. Better outcomes where failure simply isn’t an option.

That kind of evolution matters when you’re coating buried pipe, welding after backfill, and asking a system to perform flawlessly for decades underground.

If you’re in the water pipeline construction world and dealing with these kinds of challenges, we’d love to talk. There’s a lot of hard-earned history—and a lot of practical knowledge—behind today’s Waterwrap systems, and we’re always happy to share it.

Raychem GRS Gas Repair Sleeve

 

A Little Pipeline Safety Time Capsule: The Story of Raychem’s GRS Sleeve (1973)

If you’re a safety-minded person—or just someone who enjoys a bit of pipeline history—you’ll appreciate this one. Every industry has moments that make us look back, shake our heads, and say, “Wow… things were really different back then.” And in the world of pipeline coatings, June 1973 in Richmond, Virginia, gave us a perfect example.

At that time, Raychem had developed a product called GRS—Gas Repair Sleeve. Its purpose was straightforward: seal a leaking natural gas line. But the installation method? Well… that’s where the story gets interesting.

GRS was a heat-shrinkable repair sleeve, and like all early shrink technologies of that era, it required an open flame for installation. Yes, you read that correctly:

Open flame.

On a gas line.

That’s already leaking.

Down in a hole.

It’s the kind of detail that makes today’s safety professionals cringe—and also appreciate just how far the industry has come in engineering, risk management, and installation practices.

Technically speaking, GRS was a wraparound product. It used Raychem’s classic rail-and-channel closure system, allowing the sleeve to be wrapped around the pipe, locked into place, and then shrunk to form a seal. For its time, it was clever engineering, and thousands of these sleeves were installed across the country.

But unsurprisingly, as safety standards evolved, GRS didn’t make the cut for the long term. The product was officially discontinued in the 1990s, though many operators still encountered them in the field years later—testament to just how widespread they once were.

Looking back, GRS is a reminder of two things:

1. Innovation often starts with bold ideas, even if those ideas don’t stand the test of time.

2. Safety evolves, and what once seemed acceptable can later become unthinkable as we learn, improve, and push the industry forward.

And that’s what makes these historical snapshots so fascinating. They show us where we’ve been—and how much better we’re doing today.

1973 Job Report

 

A Blast From the Past: Raychem Shrink Sleeves in 1973 — and How Covalence Continues to Lead Today

Every once in a while, a photo pops up that reminds us just how far the pipeline industry has come. This morning delivered one of those gems:

July 1973 — Tampa, Florida — Raychem Shrink Sleeves being installed on 45s, 90s, and straight-line field joints.

Back then, Raychem was the name everyone knew for heat-shrinkable pipeline coatings. Over the decades, the brand evolved into Covalence, now part of Seal for Life Industries, owned by Henkel. But that original innovation DNA? Still very much alive.

And the picture from that Florida project?
A completely different world.

No shirts.
No gloves.
No FR clothing.
No PPE.
Just a crew, a torch, and a box of Raychem sleeves — and somehow, no problem!

Despite the “old-school” approach, those early shrink sleeves performed incredibly well. The technology was solid, the materials were ahead of their time, and Raychem quickly became the global standard for field joint coatings.

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From Raychem to Covalence: The Same Heritage, But a Much Bigger Toolbox

Fast-forward 52 years, and Covalence remains one of the industry’s most trusted names — not because the products stayed the same, but because they kept evolving.

Today, Covalence offers field-proven solutions for:

• Straight pipe

• Hot bends

• Cold bends

• Fittings

• Tie-ins

• Directional drilling

• Road bores

• Specialty applications

If there’s a pipeline, chances are Covalence has a coating for it.

And while those 1973 TPS slip-on sleeves got the job done, our approach to bends today is even better.

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Why Today We Recommend Covalence Flexclad for Bends

If you were coating 45s and 90s today, you wouldn’t be reaching for a slip-on sleeve — you’d be reaching for Covalence Flexclad, the industry’s premier heat-shrinkable wrap-around tape for bends.

Why Flexclad?

• Form-fits perfectly around any curvature

• No wrinkling or bridging

• Handles movement and strain exceptionally well

• Eliminates the difficulty of sliding a sleeve over a bend

• Delivers long-term corrosion and mechanical protection

• Proven Covalence adhesive technology underneath

Flexclad is simply the modern, reliable answer for bend coating — engineered from decades of experience that began with those early Raychem installations.

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Pipeline Coatings Have Evolved — And So Have We

As fun as it is to look back at a 1973 jobsite where safety culture meant “try not to burn yourself”, it’s even more exciting to see how far the industry has come.

Better materials.
Better chemistry.
Better installation techniques.
Better safety.
Better results.

But the through-line remains the same:

Covalence continues to deliver coating systems for nearly every pipeline application — from the simplest field joint to the most challenging bend.

The tools have changed.
The safety standards have changed.
The industry has changed.

But the legacy of innovation — from Raychem to Covalence — is still shaping the pipeline world today.