3PE heat shrinkable sleeve, also known as 3PE joint repair heat shrinkable sleeve, is mainly used for the corrosion protection of long-distance pipeline joints.
Heat shrinkable sleeve is also mainly used for anticorrosion of natural gas, petroleum and chemical pipeline. Its structure is the same as that of heat shrinkable tape, which is 3PE structure, that is, polyethylene base material layer, hot melt adhesive layer and epoxy primer layer.
Polyethylene base material layer mainly plays the role of mechanical protection, resistance to soil pressure, friction, etc. The substrate layer is the outermost layer, which is in direct contact with soil and water. The inner surface of the heat shrinkable sleeve is coated with hot melt adhesive. The hot melt adhesive layer is mainly used to bond the epoxy primer layer and the polyethylene base material layer. When we bake the heat shrinkable sleeve, the hot melt adhesive layer melts and evenly overflows 1-2cm from both ends of the heat shrinkable sleeve, making the base material layer closely adhere to the steel pipe, and insulating the air and water from entering. Epoxy primer, also known as two-component solventless epoxy primer, is applied on the surface of steel pipe and the innermost layer. Its main function is to slowly solidify the primer into a film, effectively isolating air and water. These three layers are closely combined and each plays its role to form an effective and compact whole. The primer layer is mainly applied on the surface of the steel pipe, which mainly plays the role of anti-corrosion and makes the main body of the heat shrinkable sleeve better bonded with the steel pipe surface. Before painting the primer, the steel pipe must be derusted, dehumidified and dusted according to the requirements. With these three-layer anti-corrosion structure system, it is called 3PE heat shrinkable sleeve, which is indispensable. When we use it for anticorrosion of some PE pipes, we usually don't apply primer. At this time, we call it 2PE heat shrinkable sleeve.