What is Covalence®?

Covalence® sleeves are offered in a two-layer and three-layer construction that compliment a wide range of pipe coating applications both onshore and offshore. The Covalence® DIRAX system is a patented three-layer formulation designed especially for HDD installations. Covalence® also provides sleeves for sealing in the district heating and cooling markets.

Covalence® heat shrink sleeves meet all relevant global standards (ISO, EN, AWWA, NACE, GOST) ensuring suitability for pipeline applications and special field conditions. Covalence® sleeves come in various thicknesses and can accommodate any diameter pipe. Easy-to-understand installation instructions are shipped with every product and clear product labelling allows rapid on-site identification.

Why use Covalence®?

Covalence® heat shrink force technologies provide strong mechanical strength performance and corrosion protection for oil, gas and water transmission pipelines. With technology born of the atomic age, shrink sleeves are unique in their ability to perform safely and efficiently.

Covalence® has over 40 years of experience in the development and manufacturing 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 Heat Shrink Sleeve System

The Covalence® two-layer sleeve system consists of a first layer of a mastic pressure sensitive adhesive and a second layer of irradiated cross-linked polyethylene backing. The two-layer system is widely used with FBE, coal tar, epoxy, polyurethane and PE tape mainline coatings. Wire brush cleaning is suitable for all Covalence® two-layer systems.

Three-Layer Heat Shrink Sleeve System

The Covalence® three-layer sleeve system consists of an initial epoxy primer layer with a second layer of a hot melt adhesive and a top layer of irradiated cross-linked polyethylene or polypropylene backing. Covalence® three-layer sleeves are designed for use with three-layer PE or PP mainline coatings. Blast cleaning is required for Covalence® three-layer systems.

Features and Benefits

  • Covalence® has 40+ years of proven in-service performance
  • Systems conform to all pipe diameters
  • Mastic-coated sleeves balance performance, economy and ease of installation
  • Excellent resistance to cathodic disbondment, hot water immersion, thermal aging and soil stress at maximum-rated operating temperature
  • Dimpled pattern provides a “permanent change” indicator for proper heat application
  • Cost effective installation
  • Products available in uni-sleeve construction with pre-attached closure patch
  • DIRAX sleeves withstand the high stresses of HDD requirements