It is not difficult to buy a heat shrink tube in Vladivostok, but its quality leaves much to be desired. Translucency bothers me the most. The train of thought is simple: if the heat shrink is translucent, like a cover for a school notebook, then its insulation is poor. And to be honest, all these semi-pink and not green tubes do not harmonize with my wires of exclusively red, black, yellow or white color.

I prefer to buy heat shrink tubing from the hobbyking online store - there the price is more attractive, and the quality of the tubing is an order of magnitude higher. Just do not consider me an avid buyer of heat shrink: I bought once and took a meter of each tube from the diameters and colors I needed - so far there is enough, although the stocks of some are already running out. If you need more, I'll buy it there. As practice shows, a one-meter set is enough for a year of leisurely use. Heat shrink tubes are marked according to their original, primary diameter, that is, according to the size before shrinkage. On average, all heat shrinks shrink twice evenly. Some more, some a little less. In any case, it is worth choosing a tube so that the diameter of the wire is slightly larger than half the diameter of the heat shrink. For example, 14mm heat shrink tubing will shrink to 7mm, in which case it must be used with a wire at least 8mm in diameter.

How to heat and shrink heat shrink tubing?

The best tool for this job is a blow dryer. However, this thing is not cheap and buying it just for the sake of heat shrink is stupid. If you have a temperature-controlled soldering iron or soldering station, you can cauterize the tube with the thick part of the soldering iron. Not a sting, but the place where the heating element hides. Quite a working option.

Can an open flame be used for heat shrinking?

By an open flame, I mean any source of fire: a match, a lighter, a candle. In principle, the tube can be seated with an open flame, but a few points must be remembered:

1. The tube with a sharp shrinkage can be deformed and slip
2. With due diligence, heat shrink tubing can be burned through
3. The colored tube may become sooty

The main problem with using an open flame is that the source is always at the bottom, so the structure must be constantly rotated over the flame so that the tube is compressed evenly. By the way, it is advisable to keep it three to four centimeters from a visible flame: the temperature is most optimal there. It is not necessary to stick the tube directly into the flame or its base: the temperature is lower there. Turbo lighters and gas-burners I do not recommend using it - the tube will deteriorate in an instant!

Why is heat shrink better than classic blue electrical tape?

First, the tube does not unwind over time. Secondly, it does not stick to the insulated material and does not leave an adhesive layer on it. And with the right selection of color and diameter, it looks more aesthetically pleasing. By the way, it is much easier to remove the tube: it is enough to make a longitudinal incision. Heat shrink is also indispensable for insulating closely spaced contacts, for example, on connectors: it does not need to be wrapped, and therefore free space is not required.

Why is heat shrink tubing worse than regular blue electrical tape?

Except that it cannot be used to isolate structures of complex shapes, the size of which changes. If the connector has a diameter of 10 mm, and the wire is only 3 mm, then the tube simply will not reach the wire or fit on the plug.

What sizes are there?

The hobbyking site has tubes from 2 to 100 millimeters. I once was in a store with electrical goods and all sorts of powerful things - there were heat shrink tubing with a diameter of 25, and if I'm not mistaken, even 50 centimeters. Tubes up to one or two centimeters in diameter really look like tubes. And the larger ones are flattened into stripes and look like a ribbon. It is important to remember that they are all marked precisely by the diameter, and not by the width of the flattened tape. For example, a red tube with a diameter of 14 mm looks like a tape with a width of 24 mm.

The diameter of the tube and its width in a flattened state are two different things!

Which ones to take?

I'll tell you on personal experience. So here's what I bought:

• 25 mm, transparent - convenient for isolating ESC and any USB boards (hubs, modems, wi-fi whistles)
• 16 mm, transparent - suitable for connectors and some small boards, sensors or sensors
• 14 mm, red - I practically didn’t use it, because I took it for my ESCs, but didn’t calculate the dimensions; most often I cut it into thin rings and mark some cables; it is also indispensable for my Turnigy 4WD Rally car
• 6 mm, blue - for power wires; because of the color that is not the most popular for me, it was practically not used, but it will be useful for many electricians
• 6 mm, yellow - for power wires; used more often since I use the 12 volt line extensively
• 6 mm, black - actively used for wires and connectors (3.5 and 4 mm bullet)
• 5 mm, black - the absolute leader in use in its diameter, ended
• 5mm yellow - used to insulate motor connectors (3.5mm bullet)
• 5 mm, blue - helps in the color differentiation of wires, although it is not so actively used
• 5 mm, red - the second place in terms of use in its diameter, I already have very little of it left
• 4 mm, black - completely over, you need to re-order
• 4 mm, red - a little bit left and still comes in handy
• 4 mm, yellow - there is quite a lot left, usually 12 volts are not carried out with such thin wires
• 3 mm, black - over, because it is very useful for almost all wires
• 2 mm, red - ended quickly
• 2 mm, black - ended even faster

Obviously, the most popular with me are small diameters, but this is understandable: small models are thin wires. Diameters of 5-10 mm will be of interest to electricians and car enthusiasts: the former work with serious wires, while the latter like to seal everything. Larger diameters have even more specific applications, except for one: heat shrink can be stretched over tool handles and make it more convenient (and electrically safe) to handle. I use large gauges to insulate modules and boards.

In the process of performing work related to electricity, it becomes necessary to use a heat-shrinkable tube. We will talk about the features, varieties and scope of the heat-shrinkable tube further.

Features of the manufacture of heat-shrinkable tubing

For the manufacture of heat-shrinkable tubing, materials based on heat polymer are used, which have heat-resistant characteristics. As the temperature rises, the thermal polymers change shape and expand.

For the manufacture of heat shrink tubing, polyethylene is used, obtained by using low or high pressure.

By means of chemical and radiation exposure, hydrogen atoms are released and the process of fusion of molecules occurs. It turns out a fairly durable material that has high heat-resistant characteristics. After that, the material is heated, which acquires additional elasticity, but does not melt. Under the influence of high temperature, the heat polymer is able to stretch, change shape and shrink, depending on the required size.

After heating, the material has a shaped memory, which is easily restored during reheating.

For the manufacture of heat-shrinkable tubing, use:

• polyethylene,
• polyolefin polymers,
• polyvinylidene,
• polyethylene terephthalate,
• polyester,
• PVC,
• fluoroelastomer.

Main properties and requirements for heat shrinkable tubes:

• resistance to high temperatures,
• resistance to acid and alkaline solutions,
• elasticity,
• ease of deformation
• lack of flammability
• ease of extension of the tube in the presence of a gap of 300%,
• the value of strength in the process of stretching is not less than 15 MPa,
• operating voltage up to 100 W.

Most heat-resistant tubes are capable of operating in temperatures ranging from 55 to 120 °C. Some products are able to withstand temperatures up to +270 °C.

The principle of operation and the scope of use of heat shrinkable tubing

Heat shrink tubing is used as a complete insulator for the protected item. The properties of the heat shrink tubing allow it to shrink and change shape during heating. Thus, the tube, which is located on the object, under the influence of high temperature, completely repeats the shape of this object and provides insulation.

The scope of use of heat-shrinkable tubing is more expanded than that of electrical tape, which performs almost the same functions.

Thermal insulation tube is most often used to electrically insulate wires, terminals or contacts.

Areas of use of heat shrink tubing:

• cable production,
• electricity, as an electrical insulator,
• sealing of electrical equipment,
• repair, installation of cable couplings of connecting type,
• insulation and marking of electrical wiring,
• to recognize the wires use a heat-shrinkable tube of various colors,
• as an insulating material in the manufacturing process of electrical equipment,
• telecommunications and energy saving industry during installation and cable laying,
• as additional elements in nuclear energy,
• mechanisms that work in the aviation, shipbuilding, automotive and railway industries, protects against high temperatures, acids, alkalis and water.

Also, heat-shrinkable tubing is used to repair damage in electrical wiring, protect electrical wires from corrosion.

Benefits of using heat shrink tubing

• excellent protection of electrical appliances from mechanical and thermal influences,
• a variety of colors will help you choose a heat-shrinkable tube in relation to the color of the device,
• ease and simplicity of installation,
• the possibility of splicing several elements,
• providing high-quality plugs and filling irregularities,
• low cost,
• the absence of harmful components in the composition of the tubes.

Varieties of heat shrinkable tubes

Depending on the principle of operation and the device, heat-shrinkable tubes emit:

1. Adhesive heat shrink tubing, which are highly popular. Such tubes are equipped with an internal adhesive layer, which during heating helps to seal the joints. Thanks to this, the tube is attached to the object more firmly and provides a high level of protection against moisture. The value of the shrinkage coefficient of such tubes exceeds 300%. A heat-shrinkable tube with an adhesive layer is used to isolate objects in which the size differs significantly from the diameter of the tube.

2. Heat-shrinkable thick-walled tube - made of polyolefins. They are more widely used than adhesive because of their affordable cost and ease of use. These tubes come in a variety of colors. Thick-walled heat-shrinkable tubes are divided into:

• tubes with flame suppression,
• tubes with no flame suppression.

The first option contributes to self-extinguishing, in the absence of open fire, due to the use of non-combustible substances during the manufacture of tubes. Such tubes are used as an insulator in explosive industries, in the production of electrical equipment or in some military developments.

3. Special heat-shrinkable tubes - used to perform additional insulating functions in specialized enterprises.

Among the special heat-shrinkable tubes are:

• fluorescent type tubes - used in rooms with low light, after receiving light in daytime days, such tubes emit light at night;
• tubes with high voltage characteristics are used for high voltage electrical networks;
• Teflon-type tubes have an aggressive or high-temperature environment of use;
• corrugated tubes - used to cover the handles of tools or electrical appliances.

Installing heat shrink tubing professionally requires the use of a special tool, such as an industrial blow dryer or heat gun. Such a tool should have the property of regulation temperature regime and various fittings. Alternatively, at home, use an ordinary lighter, gas burner, matches, a regular hair dryer, or boiled water.

Before installing the tube, the surface of the object must be degreased and, if necessary, cleaned. To select the type of tube that is suitable for insulation, the following criteria should be considered:

• ease of installation
• ease of use,
• Terms of Use,
• material requirements.

Considering specifications pipes, pay attention to such parameters as:

• tube diameter after shrinkage,
• operating temperature,
• moisture resistance,
• working stretch,
• strength during stretching.

When choosing a thick-walled tube, before installation, the tube should be heated, then put on the object, and then heated to the required shrinkage temperature.

When cutting the tube, be careful not to have any nicks or rough cuts on the end of the tube.

During shrinking of the tubing, the recommended temperature specified by the manufacturer should not be exceeded. This will cause the tube to twist or wave-like structures.

Shrink the tubing from the middle to the ends, especially when installing the adhesive heat shrink tubing.

Criteria for correct shrinkage:

• lack of notches and waves,
• smooth surface,
• no bulges.

Photo of heat shrink tube:

heat shrink tubing cost

You can buy a heat-shrinkable tube in a specialized electrical store or on the market. The heat-shrinkable tube price depends on the quantity and quality of the material from which the tube is made. The higher the temperature regime of the tube, the higher the cost. The average price for 1 m of heat-shrinkable tubing is $5.

Overview of Heat Shrinkable Tubing Manufacturers

1. TE CONNECTIVITY is a company that manufactures heat shrink tubing. Consider two tube production series:

ATUM - heat shrink tubing with an adhesive backing, which differ high level shrinkage and have an average wall thickness. It is used as a sealant for such materials as:

• plastic,
• rubber products,
• steel,
• copper.

Versafit are flexible heat shrink tubes that are characterized by a high level of fire resistance and a low shrinkage temperature. This series is a tube that provides excellent strain relief and resistance to mechanical stress.

2. Rauchman CFM - Adhesive based heat shrink tubing. It is used to seal objects and protect equipment from corrosion. The company produces two types of tubes: with suppression and without combustion suppression.

Peculiarities:

• black color,
• operating temperature from -55 to +90 degrees,
• production material - polyolefin,
• function - protection of equipment from mechanical damage and moisture.

3. 3M BBI is a Russian company for the production of heat shrinkable tubes.

Peculiarities:

• resistance to high temperatures,
• good elasticity,
• a variety of colors and sizes of tubes,
• the presence of a tight fit to the subject.
• ease of shrinkage
• resistance to chemical and mechanical influences.

Scope of use:

• protection of tires of round, rectangular and square shape,
• bolt protection,
• armored switchgear protection,
• use for isolation of electrical substations.

4. HERE - a heat-shrinkable tube that provides reliable protection from moisture, corrosion and mechanical stress.

Peculiarities:

• resistance to mechanical influences of the external environment,
• resistance to ultraviolet radiation,
• antitoxicity,
• lack of combustion support,
• simplicity and ease of installation,
• temperature for shrinking from 90 to 125 °C,
• a variety of colors and the possibility of individual color selection.​​

A heat shrink tube (HERE) is a part that, under the influence of high temperatures, narrows and tightly wraps around the part. This property is provided by the technical characteristics of polymers, which serve as the main material for the manufacture of shrink tubes.

Specifications

When choosing a heat shrink tube, you need to focus on the following indicators:

• shrinkage ability (from 1:2 to 1:6);
• the presence of a layer of glue on the inner surface;
• the material from which HERE is made;
• color.

If you plan to use the part after shrinkage in extreme conditions, you must consider its susceptibility to high and low temperatures, exposure to chemicals and direct sunlight.

Heat shrink tubing has the following advantages:

• do not light up or immediately die out on their own;
• serve long enough;
• do not require special skills for application;
• well resist adverse influences.

Comparing the insulating tape and heat shrink, it is worth noting that the electrical tape can unwind over time and leave a layer of glue on the insulated material. Pipes look more aesthetically pleasing and are easier to remove by simply cutting them lengthwise.

Manufacturers make tubes different shapes, with thick and thin walls, suitable for use in different conditions.

How to use heat shrink tubing

On heat shrinkable tubes, two numbers are indicated through a fraction, it is important to know what they mean. The first is the diameter before shrinkage, the second is after. Nearby, the dimensions of the tube itself and its color can be indicated.

For the right choice, you need to be guided by the following rule: the diameter of the purchased tube should be wider than that of the wire or part on which it will be put on, and the diameter after shrinkage should be narrower. This is the only way to ensure high-quality insulation.

If a heat shrink with a layer of adhesive inside is required, it is important to thoroughly degrease the wire or part before use, otherwise the tube will not stick. The surface must be free from sharp edges that will damage HERE. Do not use heat shrink tubing that has holes or burrs.

Before you ask yourself how to use heat shrink, you first need to prepare tools that will heat the polymer surface. The temperature should not be lower than +70, otherwise the heat-shrinkable tube will not fit tightly and evenly. Can be applied:

• building hair dryer;
• gas-burners;
• lighters, etc.

The temperature required for shrinkage is indicated on the label.

Experts, telling how to work with heat shrink tubing, recommend focusing on the following steps:

1. The tube is put on the wire and shifted away from the junction of the wires. They must first be twisted together, then you can install the tube so that the junction of the wires is in the middle of its length.
2. Heating and shrinkage. Once the heat shrink is installed, you can start heating it. Warming up starts from the middle, then you can gradually move to the edges. The temperature must not be exceeded in any areas, otherwise the tube will sit unevenly. If there was a layer of glue inside, then when heated, it will flow out from the edges.
3. Cooling down. Until the heat shrink has cooled down, it must not be touched.

Applications

What is heat shrink tubing for? Heat shrinkage is necessary for high-quality insulation of junctions of electrical wires and parts of conductors. In addition to wires, it is used for rust protection and waterproofing. To this end, on inner part heat shrink is applied with a special layer of glue, allowing it to be attached to metal or wood.

A wide range of colors allows you to use heat shrink tubing not only for protection or insulation, but also as a mark for electrical cables or wires. The following designation has been adopted for the components of a three-phase network:

• phase A is marked in yellow;
• B - green;
• C - red.

The ground contact is usually indicated in yellow-green.

Due to its ease of use and durability, heat shrink tubing has become a great and reliable alternative to obsolete electrical tape.

After completing the electrical installation work safety issues come to the fore in the process of further operation of electrical wiring. Therefore, even at the installation stage, high demands are placed on compliance with the laying technology, quality and reliability of the connections. It is in these places that contacts are most often broken, overheating occurs, which causes a fire. To prevent such situations, there are various types of insulation, including heat shrink tubing.

Heat shrink for wires has many advantages than conventional insulating tape and is available in a variety of modifications with individual properties and specifications.

General information and scope

For the manufacture of these tubes, a special heat-shrinkable material from among thermopolymers is used, capable of changing dimensions under the influence of elevated temperature. Such heating can be generated hot water, heated air, open flames and other heat sources.

Any heat shrink tube is characterized by a higher transverse compression ratio relative to the longitudinal one. Consequently, its diameter can be reduced by several times, and its length by a maximum of 20%. High-quality products are reduced in length by only 8-10% and are in high demand.

When a segment is heated from one side, only this part will increase in size, while the other will remain with its previous dimensions. When the diameter of the tube is reduced, the thickness of its walls will increase proportionally, giving the product additional insulating properties. It immediately becomes clear why heat shrink tubing is needed.

The characteristics of heat shrink tubing enable their wide use in various fields:

• The main purpose of the products is to provide a reliable electrical insulating layer during installation work. Heat shrink is much more convenient and practical compared to conventional electrical tape, especially when in large numbers connections.
• Thermotubes are often used as cambric, with the help of which it is carried out.
• Heat-shrink tubing for wires is used not only in electrical engineering. These products have proven themselves as an anti-corrosion agent. In addition, thermotubes provide additional mechanical stability to moving mechanisms, such as conveyor rollers and rollers.
• IN production area insulation of the thermotube reliably protects against aggressive environment, including from external atmospheric influences.

Types of heat shrink tubing

First of all, each heat shrink tubing is classified according to the type of material used to make it.

On this basis, all products can be conditionally divided into the following groups:

• Polyolefin. They are based on polyethylene “cross-linked” by chemical or radiation methods. Dyes, plasticizers, materials that suppress combustion and other components are added to it. This technology is used to manufacture most of the heat shrinkable tubes capable of operating in the temperature range from - 50 0 C to + 125 degrees. Special additives can increase the bar up to 150 degrees. The material has increased resistance to benzene and strong oxidizing agents, but does not withstand long-term exposure to fuels and lubricants.
• Elastomers based on synthetic rubber. The main characteristic is considered to withstand high temperatures, up to 175 degrees. They tolerate the aggressive effects of fuels and lubricants well. The low demand for products of this group is explained by their high cost.
• PVC. For the manufacture of tubes, thermoplastic polyvinyl chloride is used, which has excellent insulating qualities, represented by many types. A significant disadvantage is the low temperature range within - 20 0 С - +80 0 С, as well as the release of toxic substances in case of fire.
• Polyester. This material has left PVC products far behind. High physical strength and chemical resistance have made this type of heat shrink tube the most popular in electrical engineering.
• Fluoropolymers. Allow to obtain products with unique physical and chemical properties, such as good shrinkage temperature, capable of performing any specific task. Short consumer demand explained sophisticated technology production and high cost of products.
• Silicone. Tubes made from this material are flexible and non-toxic. They have increased chemical inertness and electrical strength. The only downside is low stability to the effects of organic solvents, which limits the use of silicone tubing in the field of fuel and lubricants.

Additional product classification

Each heat shrink tube can be classified according to other criteria. First of all, the separation occurs according to the method of installation. This procedure is performed with or without an adhesive layer. In the first case, the adhesive is applied from inside the tube, thereby providing the necessary sealing, including protection from moisture. After shrinkage, such products decrease in diameter by about three times.

Of great importance are the varieties of tubes in terms of wall thickness. All of them are available in the following versions:

• Thin-walled.
• Walls of medium thickness.
• Thick-walled.

For special cases, special varieties of products with additional technical characteristics are produced. Could it be heat shrink tubing? large diameter, with a corrugated surface, with fluorescent additives, high electrical density and other useful properties.

Properties

All the working properties of heat shrink tubing are due to the thermopolymers from which they are made. Under the influence of elevated temperatures, they can be easily heat-shrinkable, that is, they change their shape - they shrink or expand. That is, it is enough to put the tube on some object and heat it up with a special hairdryer or an ordinary lighter. As a result, its size will instantly decrease, and shrinking, it will tightly fit the object. The most important thing is to prevent overheating, otherwise bubbles will appear in the tube and it will lose its physical properties.

Radiation and chemical effects on the polymer during the production process lead to the release of hydrogen atoms and the fusion of molecules of the polymer substance. This leads to the creation of a strong "cross-linked" material with increased thermal stability. When heated, it becomes more elastic, but it does not melt, but simply changes its shape. A properly selected material after heating acquires the so-called shaped memory, with the help of which the configuration is restored after repeated heating.

Thus, the main properties of heat shrink tubes are the ability to change the thickness and diameter, the ability to work in a wide temperature range, color them in various colors. The latter property allows the use of products as wire and cable markings during installation. To control the quality of electrical connections, a transparent heat-shrinkable tube is often used.

Characteristics

The main technical characteristic of heat shrink tubing is considered to be a shrinkage coefficient of 200-600%. With it, each heat shrink tube marks its dimensions before and after heat treatment.

The ratio itself is displayed as 2:1, 3:1, …. 6.1, etc., indicating the ability to compress by 2, 3 ... 6 or more times.

Adhesive heat shrink tubing provides reliable tightness, waterproofing and anti-corrosion protection of joints. Under the influence of high temperature, the glue melts, and then after cooling it makes the tubes more durable and resistant to mechanical stress.

The high shrink ratio is very useful when working in difficult wiring conditions, with a lot of bends and turns. In this case, tubes with a large diameter and subsequent large shrinkage make them much easier to put on. An important role is played by heat shrink for wires and its dimensions before and after heating. These data are indicated in the marking in the form of a fraction sign.

The choice of a suitable diameter is carried out in such a way that the tube is freely put on the junction, without causing damage. Ideally, it should be at least 10% larger than the diameter of the insulated place. After shrinkage, the tube, on the contrary, decreases by 15-20%, guaranteeing high-quality compression and a snug fit.

Marking

To do right choice, you must be able to read the description and labeling on the product.

As a rule, the marking indicates the main parameter of heat shrink tubing - inner diameters before and after heating and installation. The first figure determines the factory dimensions of the product, and the second - the degree of compression in the free state after putting on the cable and heating.

The shrinkage ratio can be marked 2:1, 3:1, etc. or diameters in millimeters, indicated through a fraction: 10/5, 8/4, 60/25 mm. European and American manufacturers carry out similar designations in inches.

How to choose the diameter

The choice of a particular product largely depends on the operating conditions. Therefore, the tubes must have the appropriate technical characteristics and indicators of resistance to various types impacts. For example, for a high-voltage cable, special products with increased protection are selected that can withstand up to 1 kV.

When selecting the diameter, the method in the form of "-10 + 20" is used. It means the limits of the minimum and maximum shrinkage, which is selected in accordance with the dimensions of the conductors. This factor should be taken into account when choosing the length, which will also decrease. For high-quality pipes, the longitudinal shrinkage is only 5-7%, while for Chinese fakes - 20%.

It is quite easy to make a choice according to the initial characteristics. It is much more difficult to correctly determine what dimensions the product will take at the end of installation. It is believed that the higher the shrinkage, the thicker the walls will become after heating, contributing to an increase in the strength of the connection.

How to use heat shrink

Installation of tubes is quite simple, especially in domestic environments where special tools are not required. For heating, you can use a simple lighter or a gas burner. It is best to work with an industrial hair dryer, which provides a neat and uniform shrinkage. Each heat shrink tubing is easy to put on and anyone can learn how to use it.

A piece is cut off from the common tube, the length of which should be more plot by the amount of longitudinal shrinkage. The media is made evenly, and scratches are not allowed on the surface to avoid rupture of the tube under the influence of heat.

The tube worn on the conductor heats up in the direction from the middle to the edges if it has a long length or an inner layer of glue. Heating from edge to edge is carried out in order to avoid significant longitudinal shrinkage. Simultaneous heating on both sides will lead to the formation of air bubbles at the joints, and the tube itself will become wrinkled. The area should be heated evenly, avoiding overheating.

Heat shrink tubing is an innovative insulation method that is used when working with electricity. This material is much preferable to traditional electrical tape, as it creates a uniform, completely sealed electrically insulating layer.

When asked how to heat a heat shrink tube at home, we will try to give a detailed, constructive answer.

Main characteristics

A heat shrink tube is a special insulating element that, when heated, changes its diameter, indicated in millimeters (mm), reliably protects and isolates the base placed inside from damage.

Heat-shrinkable tubes are made from heat-polymer materials with high heat-resistant performance.

There are certain requirements that apply to heat shrink elements:

• elasticity;
• high temperature resistance;
• lack of flammability;
• resistance to aggressive environment;
• fast deformation;
• tensile strength - 15 MPa and above;
• elasticity - the ability to increase by 300% of the original size.

The most popular insulators are tubes that can deform at temperatures from 55 to 120 degrees Celsius, but there are products that can withstand heat up to +300 C.

The properties of this thermal insulation allow, when heated, to completely follow the contours of the object to be insulated.

Basically, thermal insulation elements are used for electrical insulation of contacts, wires, terminals, but in some cases they protect with this material hardware from corrosion.

Application area:

• electricity;
• cable production;
• protection of equipment used in electrical work;
• installation, repair of couplings;
• marking wiring during insulation through the use of elements of different colors;
• in the nuclear power industry as an addition to the installation work.

In addition, it is used to protect the wire from destruction, insulate objects in all areas of production.

Shrinkage with an open flame - pros and cons

An open flame is a lighter, candle, match, or other source of fire. If we consider an open flame for heating, then it is worth knowing some of the nuances:

1. Thermal insulation with strong heating can undergo severe deformation;
2. If the flame is not removed in time, then the heat shrink may simply burn out;
3. White, colored heat-shrinkable element, may smoke when heated.

The main problem of open fire shrinkage is that the source of heat is always at the bottom, and in order to evenly heat the insulator, the connection must be constantly rotated. This is the only way it will heat up evenly.

In addition, it is necessary to strictly observe the distance from the structure to an open fire. It should not be less than 3-4 cm, it is at this distance from the flame that the temperature indicator is highest.. You can not use gas burners or turbo lighters for heat shrink tubing for heating - it will immediately become unusable.

Application of various methods for heating

There are several heating methods, each of which can carry out heat treatment with high quality. But there are some that are not recommended.

The most widely available, at the same time controversial option - lighter or matches. This option can be used if there is no other source of high temperature at hand. Only a small section of wire with a small cross section can be well seated in this way. For large structures, this option is not suitable.

If we are talking about large products, then it will take a long time to heat up, while the connection itself will turn out to be of poor quality. And how many times do you need to repeat this procedure if you need to process several areas with a large cross section.

The same can be said about the lighter. Some home craftsmen try to use an ordinary hair dryer for shrinkage, which every housewife has. But it is worth remembering that this device cannot give desired temperature, so high-quality compression of the insulation will not work.

Important! Depending on the brand of material, the heating temperature is 90-150 degrees.

A household hair dryer produces a stream of hot air t 700 C at the outlet of the nozzle. If you use a narrow nozzle, then of course it is possible to heat a small area of ​​​​small diameter, as for large sections, the hair dryer will simply fail, while the insulation will turn out to be of poor quality and not reliable. Do not forget that there are some models of heat shrink that can be compressed at a heating temperature of 350 degrees.

The result of such work may be a loose fit of the material to the place of insulation, into which moisture can easily penetrate, so you should use a special tool.

Shrink tools

In fact, there are only five building tools for heating. Consider them:

• building high-temperature hair dryer for heat shrink tubing;
• special burners based on butane;
• gas soldering irons;
• propane burners;
• infrared device.

The most optimal option for heating heat-shrinkable, thin-walled elements is a building hair dryer. Its temperature regimes can be adjusted, in addition, you can purchase special nozzles for uniform heating.

Its disadvantage is that the heating of thick-walled material will be long, the compression quality will be unsatisfactory.

Before you start heating with a hair dryer, you need to hold the heating area with your hand so that the element does not move from its place due to a strong air flow from the nozzle.

The infrared burner does not have these drawbacks, as it heats up in a matter of minutes, without a strong air flow.

Important! When using infrared radiation, it is worth knowing that the elements are black, or dark shades absorb heat faster, so it is likely that thermal insulation will burn through when heated.

Gas burners are good to use as the flame has several functions. It should be understood that shrinkage should be done on the softest flame. How can you tell if a flame is soft? Adjust the burner so that all flames are yellow, the same values ​​\u200b\u200bshould be applied when using a gas soldering iron.

Interesting to know! Since this thermal insulation is used everywhere, including in mechanical engineering, the question arises: how to heat a heat shrink tube for a gas pipeline. There is one most important limitation, you can not use open fire in any form for heating. It is better to use a building hair dryer, or an infrared emitter to isolate the gas line.

A propane torch is the most suitable tool for compressing thick-walled thermal insulation elements.

The correct choice of devices for shrink work depends on the following nuances:

1. The size of the thermal insulator;
2. wall thickness;
3. Manufacturing material.

Before choosing one or another heating method, study the characteristics of the material that you plan to use.

Watch the video - how to use shrink tools, how to heat, etc.

Why is heat shrink better than electrical tape?

There are two main indicators by which thermotubes are preferable to insulating tape:

• using a thermal insulator, you can not be afraid that it will lose the desired properties over time;
• electrical tape sticks to the insulated surface, and leaves a dirty mark on it. As for thermotubes, with the right choice of shade, you can get an aesthetic appearance of any product. It is not difficult to remove the material: you just need to cut the heat shrink tube along;
• very convenient material, if the contacts are very close to each other and it is problematic to wrap with electrical tape - there is not enough space.

Thanks to their positive qualities thermotubes have become so popular and are used in many areas of activity.

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Varieties of tubes, how to choose according to characteristics

There are several types of heat-shrinkable tubes that differ in the device and the nature of the work:

1. Adhesive heat shrink tubing inside has an adhesive layer. This is a very popular material for insulation, since when heated, the joints are completely sealed. This makes the connection reliable. The shrinkage coefficient of this tube is 300%, which allows you to isolate objects whose diameter is much smaller than the tube itself. The adhesive heat shrink tube can be cut if it is not possible to put it on the entire element, and then heat it up, thanks to the inner layer, the seam is hermetically soldered.
2. Thick-walled heat-shrinkable tube - made from polyolefin. This is a very affordable insulator, it is easy to use, and such a tube costs much less than glue. This thermal insulator has a very wide range of colors and can be divided into:

• without flame suppression;
• flame retardant thermotubes.

The second option is used as a heat shrink in the production of electrical engineering, the military industry, explosive enterprises. These thermotubes are able to self-extinguish if they are not exposed to constant open fire, since non-combustible substances are used in the production.

1. Special thermotubes - used in specialized enterprises for additional insulation. There are several types of material:

• fluorescent - used in poorly lit rooms, these tubes absorb light energy during the day, and at night they begin to give it away;
• high-voltage elements - used for insulation work, for the installation of high voltage networks;
• teflon - used in the chemical industry;
• corrugated - used to isolate tool handles and electrical appliances.

1. Fabric heat shrink tubing - flame retardant, halogen free, braided fiber. Used to prevent abrasion and mechanical damage to wires, plastic pipes. When heated, the fabric insulation reduces in size by half, which makes it possible to insulate irregularly shaped products.

These are the most common types of heat shrink insulators, which are used in all areas of production.

What are the best tools to use and why?

Experts advise using polyolefin tubes. Why, out of the total number of heat-shrinkable tubes, is this one preferred?

The fact is that thanks to the material of manufacture, these tubes received the following characteristics:

• resistance to chemical influences;
• incombustibility and fire resistance;
• tensile strength;
• good shrinkage.

This is a reliable product that is produced according to latest technology, and according to the requirements production process. They are produced in any configurations and for different kind thermal insulation.

Installation

Before installing heat shrink insulation, the surface must be prepared - cleaned and degreased. You need to cut the tube in such a way that the edges are even and have no notches.

Heating is carried out without exceeding the temperature regime recommended by the manufacturer. Otherwise, the tube will sit unevenly. Heat shrink insulation is heated from the middle, gradually moving towards the edges.

Correct shrinkage is:

1. Absence of irregularities and waves;
2. Ideally smooth surface;
3. Absence of blisters.

We examined in detail how to heat a heat shrink tube at home - there are many options and everyone can find the right one for themselves.