The Shrinkage Ratio Of Heat-shrinkable Pre-insulated Tubing Is Typically Between 2:1 And 4:1.

In the standard specifications of heat-shrinkable pre insulated sleeve, the common shrinkage ratios are between 2:1, 3:1 and 4:1. For a pre insulated junction sleeve with a nominal ratio of 2:1, its diameter will shrink to half of its original size after heating; while for a 4:1 ratio, the diameter will shrink to about a quarter of its original size, thus allowing it to cover larger and more complex shaped parts.

When selecting an appropriate shrinkage ratio, the maximum diameter of the object to be covered should be taken into account, and a insulated joint sleeve size should be selected where the expanded diameter is slightly larger than the maximum diameter but can fit tightly after heating.

Different shrinkage ratios correspond to different design requirements. For example, 2:1 is often sufficient for cable bundles with small diameter differences and regular shapes; if the object to be covered has large diameter differences or irregular shapes, 4:1 offers greater flexibility and versatility.