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Advantages of Covalence® Heat-shrinkable Products

Demanding applications

In order to protect metal pipe structures in contact with an electrolyte (soil, water) coatings need to have a high electrical resistance and low permeability to hydrogen and oxygen. The coating must also be physically strong and chemically stable. Additionally, the requirements of particular applications, e.g. high operating temperature necessitate specific tailoring of pipeline coatings.

Optimal solutions

To provide the optimal solution for each application, Covalence® offers a range of products based on an irradiated crosslinked polyethylene carrier, combined with a hotmelt or mastic coating. The main purpose of the crosslinked carrier, called ‘backing’, is to provide a strong barrier against electrical current, permeation and mechanical forces. The adhesive assures long-term bonding of the backing to the pipe, and provides added electrical resistance and mechanical strength. Thickness of the backing and adhesive depend on the application requirements.


For the increasingly common three-layer factory-applied coatings, Covalence® has developed a three-layer field-applied joint coating. To provide a homogeneously coated pipe surface in the girth weld area, a layer of two-component epoxy is first applied to the pipe surface. A specially designed shrink sleeve is then applied over the wet epoxy. The three-layer coating performs extremely well in resisting cathodic disbondment. It offers high shear resistance against soil load, and consequently ensures long service life.

High reliability, high performance

Covalence® has over 40 years of experience in the development and manufacture of heat-shrinkable products. Continuous improvement ensures state-of-the-art performance. Approval by testing agencies around the world guarantees suitability for individual applications and field conditions.

  • Two-layer and three-layer constructions complement wide range of pipe coatings
  • Top quality hotmelt, copolymer coated sleeves resist elevated pipe operating temperatures and soil stresses on all pipe diameters
  • Mastic-coated sleeves balance performance, economy and ease of installation
  • Three-layer sleeves with epoxy primer and hotmelt copolymer have excellent resistance to both cathodic disbondment and hot water immersion even at maximum rated operating temperature
  • Fiberglass-reinforced sleeves withstand the high stresses of directional drilling
  • Self-healing adhesive flow automatically repairs minor mechanical damage
  • Dimpled backing providing a “permanent change ”indicator for application of heat.

Low installation cost

  • No primer required for two-layer products – install directly on cleaned, preheated surface
  • No waiting for primers to cure – install three-layer sleeves directly over wet epoxy primer
  • Simple tools such as hand brush, power brush or blast-cleaning, propane torches
  • WPC products available in Unisleeve construction – with pre-attached closure patch
  • Easy-to-understand installation instructions are shipped with every product, while clear product labeling allows rapid on-site identification.

Premium service

To place an order, or inquire about existing orders, deliveries, product documentation and information, contact the customer service center. Product documentation and information can also be found on the Berry Plastics CPG website ( Berry Plastics CPG field engineers can provide training and certification for contractors crews, either on site or at Berry Plastics CPG facilities.