Heat shrinkable joint sleeve or cable patch is the most commonly used joint coating and anti-corrosion product, but it can not avoid some problems, such as the warping of the edge of the heat shrinkable joint sleeve. Generally, there are two factors that cause this problem.
1. The width of solventless epoxy primer applied on the steel pipe surface is not enough, or the two ends are not applied with primer. The edge of the heat shrinkable sleeve is not well bonded.
2. It may be that the baking is uneven, the two ends of the heat shrinkable sleeve are not well heated, resulting in not fully contracting to the steel pipe, so that the steel pipe surface cannot be well bonded. The baking is even and the heating is uneven. The hot melt adhesive on the inner surface of the heat shrinkable sleeve does not melt completely. This kind of situation is quite common. Because many construction workers use it for the first time, they don't know how long it takes to heat it, so they often stop heating without heating it in place.
Solution: in the face of the above two situations, first of all, we should brush the epoxy primer on the surface of the steel pipe as thin as possible, and the width of the brush can appropriately exceed the width of the heat shrinkable sleeve. Heat shrinkable sleeve shrinks back, not as wide as before, but we still suggest that it should be painted a little wider. Another point is that when we heat and bake the heat shrinkable sleeve, we must bake it fully from the middle to both ends, and heat it evenly in the circular direction until the glue overflows evenly at both ends of the heat shrinkable sleeve.