Heat Shrink Tubing: What it is, How to Use it, and How to Choose it

What it is…How to choose it…
Heat shrink tubing is exactly what its name indicates: itThere are several factors to consider when choosing
is tubing that shrinks when heat is applied. It can beheat shrink tubing. Beyond the usual considerations of
used for a wide range of purposes and can be helpfultemperature and voltage ratings, environmental
for doing both preventative maintenance and makinghazards, and other application requirements involved in
repairs.choosing cable products, heat shrink tubing requires
How to use it…attention to a few more details.
Heat shrink tubing can be used many different ways.First are sizing requirements necessary to ensure that
Common preventative maintenance applicationsthe heat shrink will fit snugly in its application and work
include relieving strain, providing additional insulation, andthe most effectively. The sleeve diameter is crucial in
sealing the cable.heat shrink tubing. The tubing must be large enough in
When heat shrink tubing is applied to terminals orits original state to fit over any large or irregular
connectors, it can help relieve physical stress causedsurfaces, but it must also have a final diameter small
by flexing and bending. While flexing and bending canenough to ensure that it will shrink to fit tightly around
damage insulation and even the cable's conductor, athose parts. That is where the shrink ratio comes in.
layer of heat shrink tubing helps the cable withstandThe shrink ratio indicates how small the tubing will
impact, even in cables with built-in strain relief. For morebecome once heat is applied. These ratios usually
challenging flex applications, requiring firmer strain relief,range from 6:1 to 2:1. For tubing with a 2:1 ratio, the final
semi-rigid heat shrink tubing is recommended.product will be half of its original size once it is heated.
Not only can heat shrink tubing provide additional strainTubing with a 6:1 ratio, in its original state, will be six
relief, but it can also provide extra insulation. Heat shrinktimes larger than the final size of the tubing after it is
tubing has great electrical qualities which makes it idealshrunk. These high shrink ratios leave room for irregular
for use with connections, terminations, and circuit boardparts, allowing the tubing to slide over large objects
applications requiring additional environmental andwhile shrinking enough for a snug fit over smaller
electrical protection.sections. This is important to ensure that the heat
Heat shrink tubing also provides an extra layer ofshrink provides an adequate fit and an effective seal.
protection for the cable by working as a sealer. It canOther considerations are wall thickness and rigidity.
be placed over substrates, connections, joints, andRequirements for these depend on the individual
gaps to protect them from moisture, chemicals, andapplication. Stiff tubing with thick walls may be
dust. Tubing defends against environmental hazards bynecessary for applications where extreme durability
providing UV, oxidation, corrosion, and abrasionand strain relief are primary concerns. For other
resistance as well.applications, thin walled or less rigid tubing may be
Although heat shrink tubing can be utilized in manyperfectly adequate.
preventative maintenance applications, it can also beAnother thing to consider when choosing heat shrink is
extremely helpful when making repairs. Whether thehow the tubing will be heated. Consider adding a heat
fixes are temporary or permanent, heat shrink tubinggun to your order. Heat guns are recommended
can be used to cover damaged cable jackets,because they provide control over temperature and air
insulation, connections, or cable splices. It makes for aflow. However, butane torches may also be used to
quick and easy fix while you wait for the cable to beapply heat. Ideally, heat is applied evenly over the entire
replaced, but it also works effectively enough to servesurface of the tubing.
as a permanent repair in some cases.The shrink temperature also varies from material to
When making repairs to the jacket or insulation, bematerial, so be sure to check that the temperature is
sure to check that the rest of the cable is undamaged.realistic for each application.
Look to see that the conductor and any insulationThough these are all important things to consider when
between individual conductors are intact to avoidchoosing heat shrink tubing, it is a tool well worth the
shorts.thought. It can be helpful in many situations, from big
Finally, heat shrink tubing can simply be used to makeprojects to small details, from important factory repairs
life a little easier. It can bundle and organize cables orto simple circuit marking.
just mark circuits for easy cable identification. HeatNow that you know more about heat shrink tubing,
shrink tubing is available in a wide variety of colors andwhat it is, how to use it, and how to choose it, go
can be printed with permanent labels, so markingahead and start looking for the perfect heat shrink
circuits is simple.tubing solution for your needs.