Views: 0 Author: Site Editor Publish Time: 2025-12-12 Origin: Site
For any electrical project to be effective, it's important to protect the cable joints that connect internal components. Moisture, dust, and other contaminants are serious threats to these joints, but fortunately, we have shrinking technology that helps to insulate and protect them.
Generally, shrinking can be grouped into two major classes - heat shrink and cold shrink. Both are similar in many ways, but they also differ due to their underlying technologies. In this article, we'll break down the heat shrink vs cold shrink debate to see which option you might want to go with depending on the nature of your project.
A heat shrink is basically a protective piece of tubing that is made from thermoplastic materials that shrink when you apply heat to them. The tube is used primarily for insulating electrical components, as well as reinforcing cable joints and other connections.
Heat shrink operates under the principle of cross-linked polymers. When they're being made, these tubes are expanded as their internal polymer structures remain in place. As soon as heat is added to the mix, the material's memory is activated, and the tube starts to contract to its original form.
The shrinkage causes a tight grip on the component or cable, forming a sealed protective layer that improves insulation and prevents the entry of dust and moisture.
Today, heat shrink tubing can be made from different engineered polymers. Some of the more common options include:
Polyolefin: A polymer with optimal heat and chemical resistance, as well as electrical insulation
PVC: A more affordable option that's very flexible and works well in light applications
Elastomeric Materials: Great for heavy-duty work, offering strong toughness and flexibility.
Fluoropolymers: Great temperature and chemical resistance overall
Adhesive Lining: An added inner layer of hot-melt adhesive that seals moisture
Flexibility is one of heat shrink's biggest benefits. You can find these components used in fields like:
Here, what shrink helps to protect any exposed conductors and reinforce cable joints.
In cable termination methods, a heat shrink can offer environmental sealing and stress control, especially at cable ends.
A heat shrink will protect your cables from the effects of impact and even abrasion.
Heat shrink can also work for solder joint insulation and protecting internal components from environmental stress. Plus, color-coding your heat shrink can help with identification.
While heat shrinks are great, there are specific projects where the application of heat can be considered a bit of a safety hazard. This is where the cold shrink comes in.
Over the years, cold shrink technology has emerged as a potentially safer and quicker alternative to heat shrink ruting. And, for some experts, this process could even be more efficient.
Like the heat shrink tubing, a cold shrink is a sealing device made from a pre-stretched elastomer rubber. This rubber - usually EPDM or silicone - will immediately contract onto a connector or cable as soon as you take out its inner core.
The application of pre-stretched elastomer technology provides a new outlook towards shrinking in general:
The cold shrink tube expands and is held in place on a plastic core when it's made
As you install it, you place the tube over the termination area or cable joint
Take the core out, and the elastomeric material will immediately contract
From there, the sleeve tightens around the able, forming a reliable seal against moisture
Whenever you need that mix of efficiency and safety, you can count on cold shrink technology to have your back. The technology is especially great for instances like:
Petrochemical plants, oil and gas facilities, and other related environments usually have serious issues with flame or heat. Cold shrink technology ensures you can get a good moisture seal and protect your electrical components while staying compliant.
For outdoor telecom systems, overhead lines, and even terminations on poles, cold shrink technology offers impeccable moisture and UV resistance to accommodate harsh conditions.
You can also find cold shrink being used for underground vaults, medium-voltage terminations, and areas prone to flooding.
In recent times, cold shrinks have become a reliable option for rural installations, offshore platforms, and other projects where the use of heat-based tools might not be so practical.
Now that we're acquainted with the two options, let's look into the heat shrink vs cold shrink debate to see where they both stand.
When installing a heat shrink, you'll need a gas torch or a heat gun to properly ensure a shrunken tube. You'll also need to apply heat evenly to avoid things like over-shrinking and air pockets, with the entire process being quite time-consuming.
On the other hand, cold shrink offers a simpler and quicker installation method. Simply pull out the inner core of the tube, and the elastomer will conform on its own. You don't need any heat, and you get a more consistent installation process.
Working with a heat shrink will require hot air or an open flame. In the hands of an inexperienced person, this could be a hazard. We should also mention that you'll need protective gear, and heat shrinks aren't good for environments with flammable gases.
Again, cold shrink takes the cake here. You don't need a heat source to work with it, making it especially great for hazardous and sensitive environments.
How long do they both last? Well, heat shrink tubing is known to last quite long. Its materials remain stable, and it doesn't change its form if you expand or relax it.
For cold shrink, you need to consider that the rubber materials can become lax with age. So, between 2 and 5 years, you might need to swap it out.
The fact that you need to use a heat gun or torch with heat shrinking makes it a tad challenging in confined spaces. You could damage nearby insulation or other components, especially if you're not quite experienced.
Compare this to cold shrink, which can be installed without any additional components. For things like underground applications and telecom poles, this is much better.
Both options are quite evenly matched here. Heat shrink tubing can provide reliable sealing, especially when you line it with an adhesive and use the right installation technique.
The same can be said for cold shrink, which offers impeccable and consistent radial pressure that gives a reliable seal over time. So, whichever option you choose here should be fine.
There's a possibility that you would lose some radial pressure as time goes on with heat shrink tubing. While it lasts long, it can degrade if you expose it to the sun for long.
Of course, this is an issue you don't have to worry about with cold shrink technology. The elastomer holds its compression, and you can even rely on it in situations where vibration or temperature changes are constant.
For heat shrink, things like UV resistance will depend significantly on the material you use. For instance, while polyolefin is solid with UV resistance, the same can't be said for PVC. If the latter isn't UV-stabilized, it could crack.
On the other hand, cold shrink is made from ozone-and UV-resistant materials like EPDM or silicone, so it's better in outdoor or harsh environments.
In terms of cost, heat shrink also wins. It's usually more affordable, and you get different variants and sizes. Cold shrink tends to cost more because of the complexity in manufacturing, although it could also pay for itself in the long run since you won't need to do so much maintenance.
Considering the characteristics that they both have, let's see where heat and cold shrink do when it comes to their pros and cons.
Very Tight Seal: Once heat is applied, a heat shrink tube will conform to the cable and offer a secure protective layer
Multiple Material Specs: You can find heat shrink tubing in different materials and sizes, making them very flexible
Solid Insulation: Heat shrink can offer impressive strength, making it ideal for cable termination methods
Relatively Affordable: Generally, heat shrink is more affordable
Compact & Easy to Store: Thanks to a lightweight build, heat shrink tends to take very little space
Heat Source Needed: You need a torch or heat gun, and this can be a bit dangerous
Temperature Sensitivity: When being installed, cold weather can make the tube stiff and even break it
Radial Pressure Degradation: Over time, the material can relax, dropping its long-term compression.
You Don't Need Heat: This makes cold shrink better for dangerous areas and underground projects
Quick, Consistent Installation: All you have to do is remove the inner core, and you're done!
Great Environmental Sealing: Cold shrink is very reliable in regions prone to water access
Very Flexible Build: For cables that are exposed to movement, cold shrink is more than suitable.
It's More Expensive: Considering its benefits, this is expected
Bulkier Before Installation: Since the rube is pre-expanded on a core, you'll need added storage space
Material-Specific Installations: You might notice some elastomers degrading more quickly in environments with some chemicals and oils.
The similarities and differences between heat shrink and cold shrink technologies are pretty clear to see. As an installer or an engineer looking to make the right choice, here are a few factors you might want to keep in mind:
You can use heat shrink when working on an indoor project or a location where exposure to temperature and water is quite low. For outdoor installations, however, cold shrink is most likely the better choice. Its sealing and compression are consistent regardless of the environment, and this is key.
As long as heat sources are allowed and safe, you can work with heat shrink tubing. But, if you're working in a dangerous or sensitive location where there's a fire risk, we'd recommend sticking to cold shrink.
Generally, you need a skilled installer to properly apply heat shrink. This installer needs to be familiar with using heat guns or gas torches too, so they don't cause any overheating.
For cold shrink, you can pretty much install on your own. For those quick deployments, this is the right choice.
Heat shrink tubing works for different voltage classes. And, the fact that you can find it in different materials means you should see an option that works for your chosen voltage stress level.
On the other hand, cold shrink is better suited to medium-voltage and outdoor uses and performs especially well on flexible cables.
How Much Are You Willing to Spend?
Of course, the money question comes into play here. Heat shrink is more affordable and easily sourced, so it works for standard installations.
While cold shrink is more expensive, it offers lower maintenance requirements and can maintain its compression for years without any hiccups along the way.
Every electrical project has its needs, and your project's needs should generally be the catalyst behind your choice - whether it's a heat shrink or a cold shrink.
Want to learn more about shrinking and electrical connections? Get in touch with us at Haivo Electrical and let's see how we can help you!
