Covalence Heat Shrink Sleeves for Field Joints
In the oil and gas industry, protecting pipelines from corrosion is critical to long-term performance and safety. One of the most vulnerable points on a pipeline is the field joint—the exposed area created when two factory-coated pipe segments are welded together during construction. This uncoated zone must be properly protected in the field using a coating that restores corrosion resistance, bonds reliably to the adjacent factory-applied coatings, and withstands environmental and mechanical stresses. One of the most trusted solutions for this purpose is Covalence™ heat shrink sleeves, formerly known as Raychem.
Covalence heat shrink sleeves have been used worldwide for decades to protect field joints on pipelines coated with Fusion Bonded Epoxy (FBE), 3-Layer Polyethylene (3LPE), 3-Layer Polypropylene (3LPP), and other common coating systems. These sleeves consist of a cross-linked polyolefin backing combined with a high-performance adhesive layer. When heated, the sleeve shrinks tightly around the joint, and the adhesive melts, forming a durable, moisture-resistant seal that prevents corrosion.
The benefits of Covalence sleeves are numerous. They offer excellent adhesion to bare steel as well as to factory coatings, ensuring a continuous protective barrier across the field joint. Installation is efficient and consistent; technicians wrap the sleeve around the pipe, apply heat using a torch or induction equipment, and the sleeve conforms tightly to the surface. This quick and repeatable process minimizes downtime on the job site and supports project efficiency.
Covalence sleeves are also designed to withstand the tough conditions pipelines often face. Once installed, they resist impact, abrasion, and soil stress, making them suitable for use in demanding scenarios such as directional drilling, rocky terrain, or road crossings. The company offers a range of sleeve products to meet various pipeline conditions and requirements. For example, DIRAX sleeves are specifically designed for horizontal directional drilling, WPCT sleeves are used for moderate-temperature buried pipelines, WPC100M is suited for standard field joint applications, and TPS sleeves are sold as tubular or slip on shrink sleeves.
Another important advantage of Covalence products is their compatibility with global industry standards. These sleeves are designed to meet or exceed specifications from organizations such as ISO, CSA, and AWWA, and are approved by many of the world’s leading oil and gas pipeline operators. Their performance has been validated in countless projects across a wide range of environmental conditions—from arctic climates in Alaska and Russia to high-temperature installations in the Middle East.
The application process for Covalence heat shrink sleeves involves several key steps. First, the weld area must be cleaned to the specified standard, usually near-white metal blast. Then, the surface is preheated to activate the adhesive and ensure proper bonding. The sleeve is positioned around the joint with overlap onto the adjacent coating, and heat is applied to shrink the sleeve and flow the adhesive. After installation, the sleeve conforms tightly to the pipe surface and forms a reliable seal. A visual inspection and optional holiday testing confirm the success of the installation.
In summary, Covalence heat shrink sleeves offer a field-proven, reliable, and efficient solution for protecting field joints on oil and gas pipelines. Their strong adhesion, mechanical resilience, ease of installation, and global track record make them a preferred choice among pipeline engineers and contractors. As oil and gas infrastructure continues to expand and age, using proven technologies like Covalence ensures pipelines remain protected and operational for decades to come.
