On a variety of electrical joints, including soldered joints and crimped connections, heat shrink tubing is employed. When heated by a heat source, the tubing covers the connection and then contracts down around it to form a tight connection.
The heat shrink occasionally needs to be removed in order to redo the connection or cut the connection apart. There are numerous ways to accomplish this, but the simplest one only requires a few simple tools and a brief amount of time.
Table of Contents
What Is Heat Shrink Tubing?
Electrical engineers and other professionals can apply heat shrink tubing, a flexible plastic layer, to components and cabling for a variety of uses, including:
- Electrical insulation – for example, to repair a damaged or exposed length of wire
- Protection – from dust, chemicals, moisture, or abrasion
- Reinforcement – relieving the strain applied by cables held at tension
- Bundling multiple wires into a single unit
- Identification – the wide range of available colors allow for easy coding
When used with cables, they are also known as heat shrink sleeves.
The name alludes to the fact that the tubing is intended to contract into place and stiffen when heat is applied, providing a long-lasting, protective coating.
Heat shrink tubing is offered in a variety of materials, sizes, and colors due to the wide range of potential uses. For added support, once the tubing is installed, some also include an adhesive liner.
Watch out for the ‘shrink ratio’ – the relationship between the original size of the heat shrink tube and its shrunken form following application. Typically, this is a 2:1 or a 3:1 ratio, with higher numbers denoting a higher ratio and, consequently, a tighter fit. For instance, tubing with a 2:1 ratio will shrink to half its size, while a 3:1 ratio indicates shrinkage to one-third the full size.
What Is Make Heat Shrink Tubing Made Of?
There are many different materials used for heat shrink, and each one has useful characteristics. Choosing the best heat shrink tubing for your needs depends on understanding their differences.
Polyolefin
The most common type is polyolefin heat shrink tubing, and for good reason. Up to 125-135 degrees Celsius (257-275 degrees Fahrenheit) it can withstand before rapidly shrinking. It is also strong, extremely flame-resistant, and flexible.
It’s important to remember that some Polyolefin heat-shrink shouldn’t be used outside because UV light can fade some pigments. The sun is always safe for black polyolefin heat shrink.
PVC
Although significantly less expensive, polyvinyl chloride (PVC) heat shrink is somewhat comparable to polyolefin. This is the solution to choose if you need heat shrink tubing on a tight budget.
This material is relatively simple to dye, so it is available in almost every color.
PVC tubing’s inability to withstand high temperatures is one of its main drawbacks. The highest temperature to which it can be exposed is typically 105°C (221°F). Be cautious when working with it as it could get burned if you touch it with a soldering iron.
Less Common Materials
- Elastomeric heat shrink tubing stands out because of its flexibility, even at low temperatures down to -75°It is impervious to hazardous substances like hydraulic fluid, diesel fuel, and temperatures as low as -103°C. It also withstands abrasion well.
- PVDF (If you need a heat shrink that can withstand flames or other high temperatures, polyvinylidene fluoride heat shrink is a good choice. Some of its other strengths include resistance to corrosive substances, fuels, and perforation.
- Silicone heat shrink is both flexible and resistant to extreme temperatures. It is frequently the material of choice for insulation in medical devices because it works well with a variety of sterilization techniques.
- PTFE (Teflon (Polytetrafluoroethylene/Teflon) heat shrink is non-reactive and has a high chemical resistance. It operates in a wide temperature range, from -55 to 175°C (-67 to 347°F), and has a very low coefficient of friction, making it very slippery.
- FEP (PTFE and fluorinated ethylene propylene heat shrink tubing are both chemically resistant materials. But it costs a little less and shrinks at a lower temperature.
- Viton heat shrink tubing is a popular option for hydraulic equipment. It is pliable, chemically inert, and creates a barrier that is effectively sealed off from all types of liquids.
What Is Heat Shrink Used For?
Heat shrink tubing is appropriate for a variety of applications due to its characteristics. Although most of these involve wires and cables, it can also be applied to other things. Here are a few of the most widely used applications for heat shrink.
Electrical Insulation
Electrically insulating wires, solder joints, splices, and terminals is one of the main applications for heat shrink tubing. Heatshrink creates a shield that stops unintentional short circuits because it is non-conductive.
Heat shrink can be utilized for repairs in addition to insulating electrical connections. For instance, a section of shrink tubing can be used to quickly fix a wire with damaged insulation and exposed copper.
Environmental Protection
Heat shrink tubing offers protection not just from mechanical harm. A barrier that protects against liquids like water, oil, or acids is also provided by this. In a similar way, heat shrink prevents the entry of dust and other unwelcome small particles.
Preventing Damage
Heat shrink is a great way to add a layer of physical protection from abrasion, unintentional cuts, or scuffs in situations where moving parts have the potential to be damaged.
You can use heat shrink to protect a variety of connectors, wires, and solder joints because its shape adapts to the components it surrounds.
Bundling Wires
If you work with electrical systems that have numerous wires, you understand how useful it is to have them organized in a tidy manner. For bundling loose wires, heat shrink is a fantastic tool. In comparison to tie wraps, it produces a neater result.
Strain Relief
Mechanical stresses on wires are relieved using strain relief. In applications like phone chargers, for instance, where wires are frequently pulled or moved, this is crucial. Fragile wires break easily without a strain relief.
Add a piece of heat shrink tubing around the bent portion of the wire for one of the simplest ways to add strain relief to cables. As a result, some forces are transferred through the heat shrink rather than the copper wire itself. As a result, the wire will endure a lot longer.
Color Coding
Color-coding wires is yet another excellent use for heat shrink. It is unnecessary to purchase wire in various colors when specific colors of heat shrink can be used to identify specific wires.
Why Should Remove The Heat Shrink Tubing?
There are many reasons why you might need to take heat shrink out of its previous application. It is not surprising that the abrasions and cuts you were preventing on your wiring end up on your heat shrink tubing since it receives the bulk of the force when it comes to protecting your wiring.
The implementation of cable organization using new heat shrink tubing that is color-coded or has personalized printing on the shell may be another reason you want to replace your heat shrink tubing.
Although it doesn’t happen frequently, heat shrink tubing can come loose with enough movement, putting your wires’ safety in danger by leaving them open to substances like liquids, chemicals, or other environmental elements.
How To Safely Remove Heat Shrink Tubing?
When heat shrink tubing has been installed correctly, it is intended to be replaced with a new one when it sustains significant damage. Your wires will be kept safe by following this easy process.
Protective Gear
When working with wiring and cable equipment, it is best to wear protective gear. Personal protective equipment, such as rubber shoes, gloves, safety glasses, and masks, can shield you from flying objects, electric shocks, and electrocution.
Heat Shrink Tubing Replacement Gear
You must first make sure you have the right equipment in order to replace your heat shrink tubing successfully. This includes:
- A blade or a pair of scissors to cut the tubing.
- To disassemble the outdated tubing, use pliers or a gripping tool.
- a ruler or measuring tape to determine the length of the wire that will hold the tubing in place.
- A heat gun is used to attach new heat shrink tubing.
Removing The Old Tubing
Find the ends of the old heat shrink tubing first, then use pliers to pry it back. The old tubing should then be cut lengthwise with a pair of scissors or a blade after this step is finished. keeping an eye out not to accidentally cut or harm the wiring underneath.
Installing The New Tubing
The wire on which the new tubing needs to be installed must be measured in length. The length of heat shrink tubing required to cover the required area should then be determined. Verify the tubing’s internal and external diameters as well. Use the heat gun to shrink the new tubing after cutting through it, distributing the heat evenly over the wire to help the wire bond.
Important Notes
Different Internal And External Diameter Of Tubing
During the installation process, it is necessary to make reference to the internal and external diameters that the manufacturer specifies in its specifications. This is due to the fact that the diameters of the tubing change as it shrinks and may not fit properly on the wire.
Different Heating Temperatures
Heat shrink tubing comes in a wide variety of forms, and each of them has a specific temperature at which they return to their original size. Before heating the tubing, it is crucial to take note of these specifications.
Hair Dryer
Despite the fact that a hair dryer can be used to heat the tubing, the temperature won’t be as high as needed. The best tool you can use to ensure that your heat shrink tubing is tightly sealed is a heat gun because it can reach extremely high temperatures.
Electrical Tape
Some individuals think electrical tape can take the place of heat shrink tubing. Although it might only last a few minutes, the electrical tape’s adhesive will quickly lose its hold.
Cutting Technique
To maintain its strength and integrity, the tubing must be cut cross-sectionally when it is being cut. It will be essentially wasted if it is cut along its length.
Recycling
Heat shrink tubing is used to protect wires and cables, but it can only shrink once after being heated. A heat shrink tubing’s performance may also be permanently impacted by the damage sustained during removal whenever it is removed.
How Can Heat Shrink Tubing Be Used Safely?
When using heat shrink tubing, it’s crucial to move slowly and follow the rules of safety to prevent mishaps or injuries. To use heat shrink tubing, follow these instructions:
- To start, pick tubing that is the right size and has the right shrink ratio. To ensure a tight fit once it has been shrunk into place, it should comfortably cover the wire or components beforehand. Remember that it will be across both its breadth and its length
- If the components to be covered might enlarge or contract after application, check the tubing’s expandability by contrasting its diameter after contraction (referred to as the “recovered diameter”) with its size before contraction (referred to as the “expanded diameter”). Check the recommended heating temperature for the tube to avoid uneven application or melts
- Using common scissors, cut a suitable length of tubing, then lay or slide it over the desired components. The shrink wrap needs to be heated right now. Hand-held heat guns or heat shrink ovens can be used for this. The latter are specialist appliances for more precise and advanced heat application
- To lessen the risk of burns when using a gun, move the heat back and forth across the tubing rather than remaining stationary. Continue until the wrap has been tightly secured
Conclusion
One of the best options for wire insulation is heat shrink tubing. It not only has excellent insulation qualities but also a number of other helpful features, including the capacity to bundle cables, add strain relief, or color-code particular wires.
Heat shrink is available in a variety of materials, but PVC and Polyolefin are by far the most widely used. For typical, low-demand applications, both of these types are sufficient and reasonably priced.
An excellent 2:1 shrink ratio kit with multiple sizes will provide you with what you need while lasting a long time if you need straightforward heat shrink for your DIY home or electronics projects.
Adhesive-lined 3:1 ratio heat shrink is a better choice for tougher applications where waterproofing is necessary. This tube fits the target components more snugly, and when it melts, the adhesive creates an impenetrable seal.
