A heat-shrinkable sleeve is a protective sleeve placed over wire, hoses and other components required to remain dry and covered. Made of a unique plastic blend, the heat-shrinkable sleeve is placed over a component and then reduced in size or shrunk to approximately one-half of its original size by applying heat. This is typically accomplished via a hot air blower or heat gun, as it is commonly called. Advances in technology have also created a woven-type of heat-shrinkable sleeve that is used in applications where the stronger woven material is used to add strength to a splice.
While it is most commonly found on electrical splices and terminal ends, heat-shrinkable sleeve use is not limited to these applications. The sleeving is also used to create corrosion protection, abrasion protection and strain relief. When used as a primary weather-insulating protection, an adhesive-lined sleeve is commonly used. This sleeve incorporates a type of adhesive that melts and flows throughout the sleeve as it is heated and shrunk. The adhesive seals out any moisture, dirt and debris that might otherwise harm the terminal connector or splice.
Often manufactured using multiple colors, the heat-shrinkable sleeve is also used to color-coordinate cables, wires and tubing. This enables workers to color code the use of the component in future repair endeavors. The shrinkable sleeve is also used to contain and hold several individual wires or cables into one singular bunch, allowing the bunch to be more easily routed throughout a conduit tube, between building floors and throughout the interior of an automobile.
The tight seal created when the sleeve is shrunk is far more protective against outside contamination than black or electrical tape, duct tape or glue alone. When cutting a piece of the heat-shrinkable sleeve, it is critical to cut the sleeve oversize. This is necessary, as the product shrinks in length as well as in diameter when it is heated.
Contrary to some misconceptions, the heat-shrinkable sleeve cannot be activated by using a common hair dryer or blow dryer. The use of a job-specific hot air gun is required for the activation of most sleeving. Some of the heavier gauge shrink sleeve can also be activated or shrunk with the help of a cigarette lighter, while the heaviest materials will require the use of a propane torch to shrink. When fire is used to activate the heat-shrinkable sleeve, it is important to guard against any accidental burning or holes in the surface of the sleeving.