The Science of Heat Shrink Tubing



For both kids and adults alike, heat shrink tubing poses a fun and practical way to cover an object. You simply slide the tubing onto an item, heat it and watch it quickly shrink down in size. However, there’s a simple science to heat shrink, making it useful in nearly any industry. Understanding its concept gives you a glimpse at other applications for this miraculous product.

 The Manufacturer’s Trick

The actual manufacturing of heat shrink is relatively simple when you see the process from the beginning. Heat shrink begins as a particular size tube, but has gas applied to its surface. The material becomes engorged with gas, forcing the tube to grow larger. Adding gas to the tube’s environment creates a lot of heat. When the tube expands enough, it’s quickly cooled down to stay in its expanded size. It can only shrink when heat is applied to it to reverse the gas process. You are essentially altering the material’s chemistry through heat application.

 Common Materials

All heat shrink is made of some plastic type. Typical materials include polyvinyl chloride, fluorinated ethylene propylene and other thermoplastics. They are chosen for their durability and strength under heated conditions. As they shrink, they must be able to stay strong as they conform to an item’s shape, even with jutting portions piercing the plastic slightly. Thermoplastics are flexible enough to wrap around almost any object, maintaining a perfectly formed structure for years of use. As more thermoplastic types become available in the marketplace, there may be even thinner heat shrinks possible for more delicate applications, such as extremely thin wires.

 Special Additives

Heat shrink isn’t just about covering an item. You can purchase specialty heat shrink that nearly forms a watertight section. Adhesives built into the plastic activate during the heating process. As the material presses down on the item, the adhesives form a bond. The tubing won’t slide or move from that point. There is also conductive heat shrink, giving you a chance to connect two electrical wires together without binding them with solder. These specialty heat shrinks need an experienced hand to make them work as directed. Improper adherence to the item creates a poor bond for both adhesive and conductive types.

 Common and Unusual Applications

According to this website, you can fix your vehicle with some heat shrink. This particularly unusual application is what makes heat shrink so versatile. Use it to fix frayed wires at home or even a broken handle on a watering can, for example. If the tubing fits onto the item, it can be fixed. Be sure to use caution while applying the heat shrink. Don’t allow the item to be damaged by the heat gun, for instance. The item’s material must be strong to withstand the heat as well.

Heat shrink continues to be a common accessory for any electrician or technical expert. Keep several tubes of varying sizes in your tool box. You’ll find their uses are endless, fixing almost any item around the home, office or vehicle.