Heat shrink cambric how to use. How to use heat shrink tubing - the subtleties of the correct application HERE

There are several ways to heat up when working with HERE heat shrink tubing. Each of them can be used with different types heat shrink, but some may not fit or even ruin the insulation.

The cheapest and most controversial option is matches. They are used when there is no other tool at hand, and heat shrinkage of very small sizes and sections. For large sizes, this is not the best option.

The result is not a very neat form of compression of the tube, and the whole process can take a long time if we are talking about larger items. And how many matches will be required if you need to isolate not one connection, but several dozen?

A lighter in this matter is also not always an assistant.

In those rooms where it is impossible to use a flame or an open fire, they try to adapt an ordinary hair dryer for drying hair. However, he is not able to create the required temperature for high-quality shrinkage compression.

The optimum shrinkage temperature is from 90 to 140 degrees, depending on the brand of the product.

A household hair dryer has a low outlet temperature, just a few centimeters from the nozzle, it can give out about 70C. Highly focused nozzles can help with heating small diameters, but the use of non-standard ones leads to the failure of the hair dryer itself. But there are thermotubes with a shrinkage of 350 degrees!

As a result, you may end up with an uncompressed or not completely isolated junction, where water can easily penetrate and absorb moisture. Therefore, instead of using improvised means, try to always use a professional tool.

Pipe tool HERE

In fact, there are 5 types of such a tool for heat shrinking in everyday life:

• • high-temperature building hair dryer (choice + order)
  • portable butane gas-burners(you can buy)
  • gas soldering irons(acquainted with current prices )
    
  • propane burners
    
  • infrared burners

    industrial hair dryer perfect tool for thin wall tubes. It has in its assortment not only temperature control, but a variety of nozzles. You can choose the required set for yourself by following the link.
    

    Of course, if you are not the owner of a cordless tool, then you can only work with a building hair dryer if you have 220 volts nearby. Even the presence of a generator does not always guarantee normal work hair dryer due to its high power.
    

    Characteristics

    

    This is its main drawback and inconvenience. In addition, it is not always possible to warm up thick-walled tubes even with a powerful hair dryer. The quality here will obviously suffer.

    Even before you start working with a hair dryer, you will have to hold the tube a little. Otherwise, a powerful jet of air can move it from its place. Infrared burner in this case has an advantage. It does not create air currents, and its rays warm up very quickly.
    

    Just be sure to keep in mind that dark pipes absorb heat much faster than light or multi-colored ones. Forgetting this, you can easily burn through the insulation.

    Gas burners have several flame functions. Heat pipes should be shrinked with a soft flame. How to understand that the flame is soft and suitable for shrinkage? It must contain languages yellow color. The same applies to gas soldering irons.
    

    A propane torch is the only tool that is optimally suited for thick-walled pipes.

    When working with a burner or a hair dryer, you need to constantly make circular translational movements. Do not stop in one place, otherwise you can easily burn through the insulation.

    In general, the choice of shrink tool depends on the following parameters:

    • wall thickness
    • tube size
    • the material from which they are made

    You can read more about these characteristics in the article “10 types of heat shrink tubing.”
    

    Rules for installing heat shrink tubing

    
    

    There is no need to rush though. First, the product warms up and shrinks around the entire circumference, and only then can you move forward gradually.

    • remember that heat shrinkage decreases not only in diameter, but also along the entire length

    The decrease, of course, does not occur by 2.3 times, but by several percent (maximum 15%). So do not be surprised if the tube HERE was originally 10 cm, and later became shorter by 1.5 cm. Therefore, when choosing the right size segments, always make a small margin.
    

    The reduction in length is especially noticeable when connecting and insulating materials of different diameters.

    For some reason, everyone forgets to take into account the height difference in this case, and it also takes a decent margin.
    

    If you do not know for sure whether the selected size will be sufficient or not, then in this case it is better to ignore the above advice about starting warming up from the middle.

    Here, follow a different rule - heat the tube not from the middle, but from one end to the other. Thus, it is possible to reduce the longitudinal contraction of its length.

    • when the heat shrink isolates any metal surface or a product with good thermal conductivity, it is necessary to preheat this surface.

    In this way, the walls stick together more tightly and the so-called “cold scars” can be avoided. First of all, this applies to tubes of large diameters; without preheating, it is unlikely that it will be possible to avoid skew.
    

    In addition, due to temperature differences, condensation can form, which you "seal" directly onto the insulation. In general, any surface of the material must be cleaned and degreased before work. This is done with a cloth soaked in alcohol or solvent.
    

    If there are extraneous sharp edges on the metal, then they need to be removed and sanded.

    • when cutting and shortening the tube yourself, do it with a sharp knife, and preferably with scissors, so as not to leave burrs. Its edges after the cut should be smooth, only in this case the tube will be seated as tightly as possible.

    
    

    Of course, in this way it is possible to increase its length by more than two times.
    However, at the same time, the thickness of the insulating wall also decreases by the same two times. And correspondingly dielectric strength will be already within smaller limits (for thin-walled it is usually 600V), and someday the phase will definitely break through to the case or another core.

    Moreover, it also decreases mechanical strength. How long your connection will now last is a mystery. If, of course, you use this option for low current, telephone cables or USB, then something may work. Plus, no one forbids in the same way to put on top of the first layer, another such stretched thermocambric.

    In the same way, some people manage to increase the width with round-nose pliers, expanding the tube while still cold.
    Thus, trying to make an analogue of expensive 4k1 from cheap HERE 2k1.

Safety is one of the main requirements for electrical wiring. Overheating, fire, contact failure most often occur at the junction. Therefore, the isolation of connections is important for reliable and safe operation electrical networks. Ordinary insulating tape does not protect against prolonged exposure to moisture, the material of the fabric tape can be destroyed over time, the joint does not look very neat. Therefore, today an alternative to electrical tape is heat shrink tubing.

Scope of heat shrink tube

Heat shrink before other insulation methods have several advantages:

• a tight fit eliminates the displacement of the insulation even under mechanical stress;
• ease of installation;
• additional mechanical strength;
• durability.

Heat shrink is made from polymer material which shrinks under high temperature. After shrinkage, the tube tightly fits the junction, exactly repeating its relief, and forms a durable hermetic coating. Therefore, its main, but not its only purpose is to ensure reliable insulation of the connections of current-carrying wires. In addition, heat shrink tubing is for a few more purposes:

• sealing and protection against moisture;
• protection against mechanical influences, dirt and chemical corrosion;
• protection of places of inflections and protection from deformation;
• restoration of damaged insulation and sheaths of wires and cables;
• tying harnesses;
• color marking.

The use of colored tubes for marking is very convenient, a small ring of the corresponding color sits on top of the insulating layer on the end of the wire. For example, in circuit wires direct current use red on the plus and black on the minus, in the ground wires - a yellow-green combined color, and in a three-phase circuit - red, yellow and green for the corresponding phases.

Large color gamut allows the use of heat shrink and as a decorative material.

In everyday life, heat shrink is used for repairs home appliances, electrical wiring insulation. Due to its durability, a variety of sizes and the ability to work at high temperatures, it is very convenient when repairing onboard electrical network and installation of alarms, radio tape recorders, autoacoustics and on-board computers in the car. On foreign car brands, rigid heat-shrinkable tubes are used for mechanical and anti-corrosion protection of fuel lines and brake hoses.

Properties and characteristics of heat shrink tubing

Heat shrink properties:

Main characteristics:

1. Shrinkage ratio from 2:1 to 6:1, that is, the ability to shrink 2 - 6 times;
2. The presence of an adhesive layer, if reliable sealing, waterproofing and anti-corrosion protection of contact joints are required. A hot-melt adhesive layer on the inner surface of the tube gives the connection additional strength and resistance to mechanical stress;
3. Resistance to aggressive environment. Heat shrinks are chemically resistant, oil and petrol resistant, heat resistant, light stabilized, with photoluminescence effect;
4. The composition of the polymer. These can be polyolefins, PVC, elastomers and other materials on which the resistance to fire, UV rays, color solutions depends;
5. The color range in which the standard and combined options from two colors. Often tubing with similar specifications is available in clear polyolefin and in black for different connection requirements.

The process of installing heat shrinks is quite simple, and in everyday life you can do without special tool. You can heat up the tube ordinary lighter or gas burner. Although, of course, industrial dryer allows you to shrink neatly and evenly.

All the complexity lies in correct selection heat shrink tubing sizes.

The initial inner diameter is always known, and the thickness of the tube and its shrinkage coefficient, that is, it is possible to independently determine the diameter after shrinkage, although usually the geometric parameters before and after shrinkage are indicated by the manufacturer. You need to know the initial dimensions so that the tube is put on the wire or connector without interference. And in order to provide reliable hermetic protection, the diameter of the heat shrink after heating must be less than the diameter of the wire connection or the product that it protects. How more shrinkage tube, the greater its thickness after heating and the higher the strength.

Choosing a heat shrink of a suitable diameter, you need to cut off a piece from it in such a way that along the length it overlaps the area that needs to be insulated with a margin for longitudinal shrinkage of the tube. This indicator is also set by the manufacturer, and is usually 5-10%.

The cut must be smooth and the surface without deep scratches, so that the tube does not break under the action of high temperature in places where there are burrs and external damage.

When the tube is put on the section of the wire that is being insulated, it is heated with a hot air gun or a lighter from the middle to the edges, if it is long or with an adhesive layer, or from one edge to the other, in the case when it is necessary to avoid large longitudinal shrinkage. If you start heating immediately from both sides, air bubbles will remain at the junction and wrinkles will appear on the tube itself. You need to warm up the entire area evenly without overheating, so that there are no gaps, charring or bubbles on the heat shrink.

It is also important to correctly select heating temperature, but this is already defined empirically. The main thing is not to rush, high temperature will not increase the shrinkage rate by much, but it will definitely lead to marriage, especially if the installer does not have experience in such work.

If it is necessary to isolate the joints with heat shrink tubes with an adhesive layer, then the sharp edges on the product are cleaned, the surface is cleaned and degreased, then warmed up.

Heat shrink tubing dimensions

Manufacturers always label heat shrink tubing. The main parameter is always the inner diameter before shrinkage. Sometimes the diameter after shrinkage is indicated through a fraction, and sometimes the coefficient by which the final diameter is calculated.

standard and most common is a ratio of 2:1.

European manufacturers indicate tube sizes in inches, and when converted to millimeters (1 inch = 2.54 mm), diameters of the type 1.6 mm, 12.7 mm are obtained.

Asian and Russian manufacturers available in multiples of 0.5 or 1 mm.

As a rule, tubes are supplied in cuts of 1000 mm (one meter each). Although there are types of heat shrinks that are supplied in bays of 50, 100 or 200 meters.

It is almost always possible to pick up two tubes of similar sizes, in which case it is better to use a product with a larger diameter.

According to the thickness of the heat shrink are divided into two types:

If you learn (and this is not difficult at all) to isolate connections in electrical circuits using heat shrink tubing, then you can quickly and reliably not only repair household appliances, but also to implement more complex networking work in a house or apartment.

A heat shrink tube is a device that can change its diameter, shrink under the influence of high temperatures. In the process of shrinkage, it will cover the object placed in it and provide protection: insulation and from mechanical damage. The scope of the tubes is radio electronics, automotive, used as a wire insulator, for protection metal pipes against corrosion, as well as for antenna equipment.

Basic statements

If to speak in simple words, then heat shrink tubing (HERE) is a replacement for the standard blue electrical tape. The only thing is that they cannot be used in areas with ornate bends and where there is different thickness along the "follow".

Their main advantage is the ability to shrink when heated, it provides the necessary insulation and mechanical protection. The cost of tubes is relatively low, ease of use is provided different colors, including the most common for cables - red, blue, green, yellow, striped. With the help of them, you can not only isolate, but also mark the wires to facilitate further work with them.

I would like to dwell on the marking in more detail, since this is one of the important areas of use of HERE. They are widely used when necessary to mark three-phase electrical circuits. They use red, yellow and green colors. By marking the same wires that correspond to a certain phase, you can facilitate the operation process. The standard option for grounding is yellow-green striping.

Material characteristics

Before using HERE, you need to choose them correctly, and for this you need to know the main characteristics. These include:

• Shrinkage ability - this ratio varies from 1:2 to 1:6.
• adhesive layer.
• The composition of the tube can be PVC, polyolefin, elastomer, fluoropolymer.
• Color - one-color, combined.

And, also resistance to such influences - temperature, chemical attack, light stabilization, resistance to petroleum products.

There is also a division according to the strength of the walls of the tube, according to this indicator HERE are thick, medium and thin-walled. The first two types are combined into one group and are characterized by a wall thickness of 1.5-4.5 mm, as it will become as a result of shrinkage. The ratios range from 2:1 to 6:1. It is in them that there is an adhesive inner layer.

Thin-walled can be transparent or colored, with a wall thickness of up to 1 mm after shrinkage, the contraction ratio is from 2:1 to 4:1. Used as insulators and as markers. They often have special characteristics, among them:

• Self-extinguishing.
• No halogen emissions in case of fire.
• Thermal resistance.
• Reduced shrink temperature.
• Improved UV resistance.
• Resistance to mechanical and chemical influences.

1. Denoting the size of the tube, manufacturers indicate two numbers through a fraction: one is the diameter before shrinkage, the second is after. Additional marking can characterize the color and length of the cut.
2. When choosing HERE, it is important to consider that its diameter must be larger than the product for which it will be used. In order for shrinkage to occur correctly, its diameter after shrinkage should be slightly smaller than the diameter of the product on which it is mounted.
3. Before using HERE, you need to inspect it for damage and burrs. If there are scratches or burrs, it is better to refuse to use such tubes.
4. If you plan to use HERE with an adhesive layer, then first the surface on which they will be seated must be cleaned and degreased. To avoid damage to the tube, the product should not have places that could be potentially dangerous for HERE. If there are sharp edges, they need to be sanded and leveled.

First you need to prepare the tools. For this, any sources that will give the necessary heat flux are suitable. The minimum temperature should be +70 degrees. The required indicators are indicated when marking. It depends on the type of tube: for a thick-walled tube, the temperature should be higher, for a thin-walled tube, it should be lower. If you plan to use a building hair dryer, then the requirements for it are to identify the required temperature. If you use gas burners, it is important that they have a soft yellow flame. Matches, lighters can be options for use as a heat source.

Shrinkage technique:

1. Surface preparation, which includes degreasing, grinding and heating. To do this, depending on the material, sandpaper or a solvent-soaked rag can be used.
2. The choice of the tube in accordance with the requirements, its heating, which is especially important for thick-walled tubes. You need to warm it up without planting it on the place of "permanent residence" and not to the maximum temperature, but by half, that is, if the temperature of full shrinkage is 120 degrees, then you need to warm it up to 60.
3. Next, the tube is placed on an insulated object, a surface. On the heating device set the required temperature.
4. Shrinkage should start from the middle. After uniform seating in the center, you should move to the right and left.
5. You need to heat it evenly, moving the heat source along it, this will not allow local overheating, and hence damage HERE.
6. If there is glue on the inner surface, then as a result of shrinkage, it should flow out. After shrinkage, the item must be left alone until it cools completely.

The application of HERE is modern and convenient solution. To feel the full benefits of this insulator, you need to use it correctly. We have tried to explain in as much detail as possible everything you need to know for a successful application HERE.

Video: how to use heat shrink tubing

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 specifications 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, impact chemical substances 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 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 joints electrical wires and parts of conductors. In addition to wires, it is used for rust protection and waterproofing. For this purpose, a special layer of glue is applied to the inside of the heat shrink, 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.

Heat shrink tubing is used for sealing, marking and insulating cables, wires and other similar components. Heat shrink insulation distinguished by its compact, aesthetic and professional look. In the seated state, the tube retains its shape, fits snugly to wires, terminal blocks and connectors. When overheated, the heat shrink does not collapse, retains its properties and becomes soft.

Depending on the application, thermotubes have different characteristics:

• shrinkage factor;
• wall thickness;
• adhesive compound.

Colored and thin-walled shrink tubes

Colored, transparent and black heat pipes with a wall thickness of less than 1 mm after shrinkage are used for marking and insulating wires. Their shrinkage ratio is in the range from 2 to 1 to 4 to 1.

Special properties of tubes:

• heat resistance;
• self-extinguishing;
• resistance to ultraviolet radiation;
• low shrink temperature;
• zero emission of halogens during combustion;
• resistance to mechanical and chemical influences.

Thin-walled tubes do not contain an adhesive layer.

Medium-walled and thick-walled thermotubes

Characteristics:

• wall thickness - 1.5-4.5 mm;
• shrinkage ratio - from 2 to 1 to 6 to 1;
• hot glue is applied to the inner surface.

For insulation power cables with an average voltage level, thermotubes with specified chemical and dielectric properties, for example, track resistance, are used. Pipes are mounted using sealing and insulating mastics.

The principle of working with thermotubes is quite simple, but there are certain nuances that a novice electrician needs to know:

1. The size of shrink tubes is indicated by a fraction, where the numerator contains the initial diameter, and the denominator, respectively, the diameter after shrinkage. Additionally, the color and length of the segment is indicated.

2. The initial diameter of the thermotube must be greater than the diameter of the product on which it will be put on. For a snug fit, after heat shrinking, its dimensions should be at least a little smaller sizes products.

3. The stronger the shrinkage, the thicker the tube walls will be.

4. Longitudinal shrinkage in length is 5-10 percent.

5. There should be no burrs on the ends of the tubes, and deep scratches and other damage on the surface.