Cold Shrink is a rubber tube or sleeve that shrinks to a size many times smaller than its original size. Unlike heat shrink, it doesn't require any type of heat to shrink in size,that’s why it is named “cold shrink”.

But Heat shrink requires heating, while cold shrinking does not need cold process . The word “ cold “ just means no heating process require. 

How does the tube shrink?

The tube is held in place by an inner plastic core which unable it to shrink. The plastic core can be pulled out by a tube inside what we call “pull cord”, that makes removal easier. The tube will shrink immediately as soon as you start pulling the core out.

The image below is an example of a cold shrink tubing before and after gluing. On the left of the image is the original or the pre-shrunk version, with the plastic core in place. Then the core is removed and the size has shrunk to the smaller size, as shown on the right.

The installation of the cold shrink tubing is very simple and can usually be done within a minute.

What is cold shrink tubing made of?

Cold shrink tubing is usually made of two materials: Silicone or EPDM: Ethylene Propylene Diene Monomer.

Silicon shrinks to a smaller and tighter size than EPDM, making it ideal for applications such as weatherproofing cell towers.

On the other hand, ethylene propylene diene monomer (EPDM) tends to be stronger and can withstand impact, making it ideal to contact with other materials, such as the interior parts of a machine.

Cold-shrink cable accessories are made of elastomer materials, commonly used are ethylene-propylene rubber and silicone rubber. Injected and vulcanized firstly, and then expanded in diameter and lined with plastic spiral supports to form various cable accessories.

When installing on site, put these pre-expansion parts on the treated cable joint or end, pull out the inner supporting plastic spiral or support, and press it on the cable insulation layer to form a cable accessory.

Because it shrinks by elastic retraction at room temperature, instead of heating and shrinking with fire like heat-shrink cable accessories, it is commonly known as cold-shrink cable accessories.

Where should I use cold shrink tubing?

One of the most popular uses for cold shrink tubing is in cell phone towers, where it is often used to protect cables/connections from water and weather. Cold shrink tubing is also used in various areas like cable trench applications, splice joints, cable protection, and in very confined or hazardous spaces where a heat gun or blow torch would be difficult to use.

Cold shrink tubing is very popular in the telecommunications market as well as in the energy, cable television, petroleum, WISP industries and satellites.