Wire lug crimping pliers: types of tools and methods of application

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In order for the contact of electrical wires to be of high quality and for a long time to facilitate the supply of electricity to the desired object, the connection must be made using the appropriate tools. Wire lug crimping pliers provide sufficient connection area. You only need to choose the right matrix size and consumables - tips and bushings.

For crimping lugs, in order to secure them at the ends of wires of different sections, hand press pliers are used

Crimping technology

There are two methods by which crimping is carried out:

• local indentation;
• complete compression.

The wire for crimping is copper or aluminum. Therefore, the sleeve can be either copper or aluminum. There is also copper-aluminium. Since an aluminum cable is prone to the formation of an oxidizing film, the aluminum sleeve must be cleanable and treated with a special lubricant. To protect aluminum from oxides, quartz vaseline paste is used. Copper wire is also subject to lubricant treatment. With its help, the likelihood of damage to the core during crimping is reduced and friction is reduced.

If the cores are multi-wire, they are aligned and folded so that they easily fit into the sleeve; you can twist the wires a little. Then the cable is inserted into the cartridge until it stops. The connection can be made not end-to-end, but, for example, with a factory. Then the total cross-section of all wires should not exceed the cross-section of the bushing.

In any case, sleeves are used that are designed for the total cross-section of the cores being crimped. If a press with point (local) indentation is used, make 2-3 pressings evenly distributed along the length of the sleeve to ensure mechanical strength of the connection and good electrical contact. For continuous crimping using hexagonal or square dies, the recommendations are essentially the same

In both cases, it is important that the sleeve does not crack during crimping (if it is too small) and that there are no uncompressed areas or cavities (if it is too large)

After the crimping has been carried out, it is necessary to create an outer insulating layer at the junction using electrical tape or elbow cloth. After insulation, you should carefully fold the wires and the cable itself in the junction box.

The video below clearly shows how to crimp wires with press pliers:

Technology

1. Remove the insulating layer by 2-3 cm from the wires to be connected.
2. Now, using fine-grit sandpaper, sand the bare areas to a metallic shine.
3. If the conductors are aluminum, apply quartz-vaseline paste to them, if copper, then technical petroleum jelly.
4. When crimping on one side, place the wires parallel to each other and put a sleeve on them. For double-sided applications, insert the stripped wires into the tube from opposite ends to the joint.
5. Crimp the connection with press pliers, wipe with a cloth soaked in gasoline or solvent, insulate with electrical tape, heat-shrinkable tubing or varnished cloth.

The wiring in the junction box using crimping is shown in detail in this video:

As you can see, there is nothing complicated in crimping, and you get a reliable and high-quality connection. If you need to do similar work of a one-time nature, you can ask someone for press pliers or rent them. If you often deal with electrical installation work, buy a tool, it is not too expensive.

How to connect electrical wires with lugs

Another way is to use tips. The tip looks like a piece of tube, cut and turned flat on one side. A hole for a bolt is drilled in the flat part. The lugs allow you to connect cables of any diameter in any combination. If it is necessary to connect a copper cable to an aluminum cable, special lugs are used, in which one part is copper and the other is aluminum. It is also possible to place a washer, brass or tinned copper, between the tips.

The ferrule is pressed onto the cable using a crimper, similar to how wires are connected using crimping.

Types of lugs for crimping stranded wires

The above article contains a lot of information about the tool used to perform crimping. But for the quality of the connection, it is equally important to choose the right tip. There are also several types of them. Let's focus on products for multi-core wires.

Related article:

Wire stripping tool: variety of accessories

Characteristics, scope of use. Types of devices. Types of strippers. Popular models from famous brands.

Copper tips. Externally, they look like a copper tube, flattened on one side, in which there is a hole for a bolt. Such tips are divided into uncoated (TM) and tinned (TML) elements. The latter are used in cases where it is necessary to make a connection with high anti-corrosion properties. Crimping of wires with lugs of this type can be carried out by any type of pliers, the matrix of which corresponds to the cross-sectional dimensions.

Copper with inspection hole. This option cannot be crimped; soldering is used for connection. The information is provided for general information. Externally, the tips are similar to the previous ones, differing only in the presence of a hole through which the position of the conductors can be seen.

Insulated lugs are suitable for stranded wires; non-insulated lugs are suitable for solid wires.

Aluminum. Aluminum wires are crimped with lugs made of the same material. Externally, they are absolutely similar to copper ones and are marked MA.

Important! Before crimping, aluminum conductors must be treated with quartz-vaseline paste. It prevents the appearance of an oxide film.

Press pliers for crimping tips of this type can be used either hydraulic or manual.

Pin. They are used to make permanent connections. They are designated by the abbreviation NSHVI - insulated pin sleeve end. The wires, stripped of insulation, are inserted into a sleeve and crimped using pliers.

Copper lugs with inspection holes cannot be crimped

Wire lug for crimping: ring, hook, fork

To connect to the terminal blocks, you need to use lugs that will ensure the most reliable connection. The main condition is that they must match the type of this terminal block. Today there are three main types of such tips:

1. Ring. Their purpose is to connect to screw terminal blocks. Providing a large contact surface is one of the advantages of this type of tip. A similar option is used for temporary and permanent connections in low-voltage networks.
2. Hook type tips. They create a contact surface a quarter smaller than ring ones. To crimp an electrical cable with lugs of this type and connect it to a terminal, you do not need to completely unscrew the fixing screw. Such lugs are more often used for temporary connections or in situations where it is impossible to unscrew the screw for some reason.
3. Fork. These tips have a contact surface that is 50% smaller than ring tips. It is for this reason that they are more often used for temporary connections when constant change of contacts is required.

There are other types of tips, but they are specific and are used quite rarely, mainly by professional electricians when installing complex circuits.

Using press pliers, you can crimp various types of lugs: ring, fork, pin

Domestic tool: wire lug crimping pliers KVT

Among the domestically produced tools, the press pliers for crimping KVT wire lugs deserve attention. The main enterprise is located in Kaluga. Particularly popular are CTF kits, which include matrices for crimping insulated and non-insulated tips, and CTF kits, which include number matrices.

The STV set consists of the following subject units:

• press jaws;
• 5 numbered matrices;
• plastic case.

The pliers are equipped with a mechanism for quickly replacing matrices. High-quality steel is used as the material for the manufacture of the tool. The design of the press has a lever for unlocking. If the matrix size is incorrectly selected, the crimping process may not be completed, as a result of which the handles will be blocked in an intermediate position. In such cases, the tool returns to its starting point using a lever.

It is worth noting that the handles of the pliers are elongated, which allows crimping to be done with two hands. Five matrices make it possible to select the option needed for a specific type of tip.

Press pliers for crimping KVT wire lugs are a fairly popular tool.

The CTF set also has 5 matrices. Pressing pliers for tips are not equipped with a device for quickly changing them, so a hex key must be used. The process of replacing the matrix takes quite a long time, sometimes even longer than the crimping itself. The STF kit (unlike STV) contains two additional screws for the matrices in case the used one is lost or damaged.

Important! When inserting the matrices, in order not to make a mistake, you need to pay attention to the size of the slot: the large one goes towards the handles, the smaller one - towards the head of the pliers.

How to brew twist

For good contact, the twist can be welded with a graphite electrode or a gas torch. Torch welding has not become widespread due to the complexity and the need to use gas and oxygen cylinders, so this article only talks about electric welding.

Electric welding is performed using a graphite or carbon electrode. Graphite electrode is preferable. It is cheaper and provides better welding quality. Instead of a purchased electrode, you can use a rod from a battery or a brush from an electric motor. It is better not to use copper electrodes. They often get stuck.

For welding, you first need to make a twist 100 mm long, so that the finished one turns out to be about 50. The protruding wires need to be trimmed. For welding, it is best to use an inverter welding machine with adjustable current. If this is not the case, then you can take a regular transformer with a power of at least 600 W and a voltage of 12–24 V.

Near the insulation, “ground” or “minus” is connected using a thick copper clamp. If you simply wrap a wire around a twist, the twist will overheat and melt the insulation.

Before starting welding, it is necessary to select the current. The required current varies depending on the number and thickness of the wire that makes up the twist. The welding duration should be no more than 2 seconds. If necessary, welding can be repeated. If everything was done correctly, then a neat ball will appear at the end of the twist, soldered to all the wires.

How to connect wires using crimping sleeves correctly

A large variety of options for connecting wires have been invented - from simple twisting to the most complex welding machines. However, among this variety, there is no ideal method. When operating the electrical network at nominal or peak loads, you can find advantages and disadvantages in each method. Crimping using a sleeve is sometimes the only correct method.

Purpose, types of sleeves and crimping tools

To ensure contact between the connected conductors, special materials are used - sleeves. They are made from copper or aluminum tubes of various diameters according to the wires being fastened, so that electrochemical equality is maintained. Crimping is used in cases where it is necessary to withstand high current loads or when using other methods is problematic.

Table. Types of produced sleeves

GML are not suitable for aluminum conductors. Metal deformations in the area where pressure is applied by the pliers cause damage to the tin coating; the conductors will come into contact with each other.

To install wiring with a cross-section of up to 120 mm², you will need manual ones, and above that, hydraulic press pliers. The professional tool is equipped with dies and punches designed for different diameters. The size is adjusted by turning the matrix or punch. When working with aluminum conductors, quartz-vaseline paste is used to remove the oxide film from the metal surface.

Features and rules for crimping wires

The crimping procedure is extremely simple: the exposed wires are tightly inserted into the tube and pressed with press pliers. If voids have formed between the wires, they must be filled with the remaining scraps of the appropriate length. Compression is carried out at at least two diametrically opposite points to obtain reliable contact. The conductors must not be twisted.

After the preparatory work, you can begin crimping. Sequencing:

1. Strip the wires of insulation and connect them into a bundle.
2. Place the lug and fill the voids with cable scraps.
3. Clamp at the edges (force is applied while rotating the tool 180°).
4. Trim the protruding edges of the cores.
5. Use heat shrink tubing to insulate exposed parts.
6. Twist the cables tightly and lay them down.

Advantages and disadvantages

Such a connection has high mechanical strength and resistance to tearing. But it is non-separable: if necessary, it cannot be disassembled to replace one of the conductors. During repairs, the old sleeve is cut out and replaced with a new one. Reducing the cable length may require an extension procedure. In general, this is the only drawback when installing electrical wiring using the crimping method.

The crimping method has the following advantages:

1. Performed with hand tools that do not need to be connected to an electrical outlet. If there is no voltage during operation, this is the only way to make a quality connection.
2. Using aluminum-copper lugs, dissimilar conductors are installed in one electrical unit.
3. If welding or soldering requires special equipment and skills to work with it, then even an amateur can do the work with pliers.
4. The crimping tool allows for commutation in confined spaces.
5. Installation is carried out quickly.
6. Operational maintenance is not carried out.

Tip sizes, design features

The minimum available sections for GML are 1.5 mm 2. Further sizes increase - 2, 4, 6, 10 mm 2 and higher. Based on these values, we can say that the cross-sections of the sleeves are equal to those of wires and cables. It is quite easy to decipher the tip designations. For example, GML-6 is a copper tip, tinned. The cross-section is 6 mm 2. In the case of combined sleeves, the marking indicates two sizes - for aluminum wire and for copper. For example, GAM 16/10 - 16 for aluminum, and 10 for copper.

By design, the sleeves can be end-to-end in the form of a hollow tube or with a partition. The latter are used when crimping wires with end-to-end lugs is performed. These partitions are located in the middle of the sleeve. With their help you can adjust the depth of the cable entry. If it is necessary to extend it, then both ends will go into the tip to the same length.

Dimensions and design features of sleeves - how to choose the right one

Connecting tubes are used for installation of single-core and multi-core cables. When choosing, take into account not only the material, but also the size of the product.

It is better to use standard data:

The quality of the formed electrical contact depends on the correct choice of diameter. The conductor must fit inside the tube and sit tightly.

Products can also be classified according to their design features. They can be hollow or with a partition. The first type is used if the connected conductors are made of the same metal. Combined devices are necessary for end-to-end wiring.

Principle of wire crimping

You can perform crimping of wires using sleeves in several ways. It will not be possible to single out the best of them, since comparison is inappropriate here. The choice of crimping method directly depends on the conditions for electrical installation work, cross-sectional parameters and other important points. Let's consider the features of the main method of crimping using sleeves.

Work begins by introducing the previously stripped ends of the wires into the cavity of the sleeve. The next step is crimping - squeezing using a special tool. The metal surface of the cores and sleeve is compressed, resulting in a reliable adhesion of the parts. It is necessary to connect at several points, followed by insulation of the connection points. An exception is working with insulated sleeves for crimping, which do not require additional insulation.

When choosing this method of connecting wires, you need to remember that the contact will not be disconnected in the future. Taking this into account, work will need to be carried out carefully and prudently.

Wire lug crimping pliers: how to choose

In the variety of terminal crimping pliers and ferrules offered by manufacturers, it is quite easy to get lost. Product descriptions in online stores are full of positive characteristics. The following tips will help you navigate and choose the appropriate tool model:

1. The choice should begin with a clear definition of the tasks. It is on the basis of these that it is necessary to select the size and functionality of the press jaws. If you have to repeatedly crimp, strip contacts and cut wires, it is worth purchasing a universal version of the tool.
2. For crimping and connecting cables with a large cross-section, it is more convenient to use a hydraulic mechanism.
3. Important criteria are the price and manufacturer of the tool. Trusted brands are always more reliable. A low cost will most likely be an indicator of the fragility of use.
4. When purchasing, you should definitely check the press pliers for crimping tips for defects and evaluate the quality of the assembly: using a visual inspection, identify possible dents and chips, check the correctness of the contact lines of the blades, and the position of the handles.
5. Be sure to pay attention to the shape of the handles. The presence of recesses for gripping helps to hold the tool more securely.
6. It is recommended to hold the pliers in your hands. Possible inconveniences associated with shape and weight will certainly appear.

Among the wide range of crimpers on the market today, everyone can easily select a tool according to their profile

The main points of the process of crimping wires and twists

To do this, you will need to strip the wire from the outer insulation, and then use a mounting knife to remove the inner protective sheath. To make it convenient to twist the wires, I personally collect the bare wires into a bundle and bend the ends.

Then, first twisting the wires by hand, I achieve greater contact through the work of the pliers with which I tighten the twist.

Having bitten off the excess wires with the same tool, I get a good connection 3-5 cm long.

Next, the only thing left to do is put copper sleeves of suitable sizes on the twists and crimp them. Moreover, crimps come in different diameters (6 mm, 8 mm, 10 mm and more). Usually, I use 6 mm products to connect strands of light groups, where the cross-section of the wires is not so large (1.5 sq. mm). For socket groups, sleeves with a diameter of 8 mm or more are taken, since here the wires have a cross-section from 2.5 to 4 sq. mm.

After that, I insulate the connections, put them in the junction box and close the lid so that everything is “feng shui”.

Types of sleeves

It is very important to choose the right sleeves for crimping wires

According to the material of execution

A copper cable or wire should be crimped with copper sleeves accordingly. They come in two types and have the following abbreviation:

• GM - copper sleeves. They are made purely of copper, do not have any coating or processing, and in appearance they look like ordinary pieces of copper pipes.
• GML – tinned copper sleeves. They undergo a tinning procedure, that is, their surface is treated with a special tin-bismuth layer. This is done in order to prevent oxidation and corrosion processes. It is also known from school physics lessons that copper, like any other metal, oxidizes. Tinning prevents this process; the crimped wires will not enter into a chemical reaction with the tinned sleeve.

I would like to give one useful piece of advice. Do not listen if suddenly one of the experienced electricians tries to prove to you that using GML sleeves it is possible to crimp aluminum wires, since the tin layer will not allow direct contact of aluminum with copper. This is incorrect, because during crimping the surface layer of the tube is deformed and the corrosion process is still inevitable.

To connect aluminum wires, they use products made of the same metal; they are designated GA (aluminum sleeve).

There are also combined sleeves, they are designated GAM (aluminum-copper sleeve), in everyday life many call them aluminum-copper. This option is used when you need to connect wires made of different metals end to end. The sleeve is a tube of two parts; at the junction of dissimilar metals, the connection is made by friction welding. Here everything is extremely simple and clear - you need to insert copper wires into the part of the tube made of copper, and an aluminum conductor into the aluminum part.

And the most modern version with the designation GSI (insulated connecting sleeves). They are based on ordinary tinned tubes, only they are covered with polyvinyl chloride insulation on top. They crimp copper wires. During crimping, the insulating layer is not removed, pliers are put on top of it, and compression is performed. Such sleeves greatly simplify the work of an electrician, since the crimped electrical assembly no longer requires any additional measures to insulate it.

By size

After the letter designations, a number is written on the sleeve. What does it mean? This is the cross-section of the conductor for which this product is designed. For example, tinned copper sleeves are produced for wires with a cross-section from 2.5 to 300 mm2. Accordingly, with an increase in the cross-section of the conductor, the sleeve itself has larger dimensions (diameter and length). For combined products, two numbers are written through the fraction, one indicates the cross-section of the copper conductor, the second - the aluminum.

By design

The sleeves also differ in design. They can be hollow, that is, inside they are bare through tubes. And they come with a partition in the middle, which allows you to adjust the depth of the conductors, that is, the tips of both connected wires will enter the sleeve to the same length. Combined sleeves are produced with partitions, which are used when connecting conductors at the joint.

Common mistakes when crimping

Cutting shells

At first glance, they are long. People who do not have the necessary knowledge and experience believe that using the entire cartridge case is wasteful, and cut it into pieces. This leads to a reduction in the length of the section where the conductors are bonded. The result is that the mechanical strength of the contact suffers, since working with pliers becomes inconvenient, and the number of pressure points decreases.

Wrong choice of sleeve diameter

If it is larger than required, then it is unlikely that it will be possible to produce high-quality crimping. The only way out is to bend the tip of the wire and then insert it into the sleeve. But such crimping is only suitable for “copper”, but the strength of the connection becomes lower. Aluminum wire breaks easily, so it is not an option.

With a smaller sleeve diameter, people without experience try to “plant” the ends of the wires into it by sharpening them a little. This is absolutely forbidden to do! Reducing the cross-section in a particular area leads to overheating and destruction of the metal. By the way, this often causes inflammation. It remains to add that the contact strength also decreases.

Crimping with pliers

Press jaws are specially designed for this specific job. Crimping with pliers is fraught with the fact that the conductor is deformed, and quite significant. After all, with this connection method it is impossible to control the clamping force. The consequences of reducing the cross-section of the core are indicated above.

Some craftsmen do crimping exactly this way, while assuring that everything is “acceptable.” But this does not mean that this technique is correct. The author came across such a situation and asked the unfortunate master a question: if he needs to do crimping at home, will he also work with pliers? As expected, there was no clear answer.

Useful tips

• It is not always possible to select a sleeve so that after placing the ends of the conductors in it, there are no voids left. The more free space, the higher the risk of poor contact after crimping it. How to proceed? The easiest way out of the situation is to cut pieces of wire (bare) with a length slightly shorter than that of the sleeve, and “hammer” them into it. Such artificial compaction will significantly improve the quality of crimping.
• If the connection of wires is made to extend the line, then their joint should be located in the center of the sleeve.

• When insulating the joint, the tape (tube) must extend beyond the sleeve cuts by at least 10 mm.
• In the case when at least one of the wires is multi-core, or different numbers of them are spliced ​​on both sides, not metal sleeves are used for crimping, but insulated lugs (NSHVI).

It turns out that there is nothing complicated about crimping with sleeves. The main thing is to choose the right size. If the reader takes into account the recommendations given, then it is quite possible to cope with such work on your own. Good luck!

Do-it-yourself crimping of wire lugs

In theory, wire crimping is not a complicated process. The presence of a tool, appropriate consumables and some physical effort is all that is needed. In reality, connections may leave much to be desired, and sometimes you even have to repeat the procedure. This sequence of actions when crimping wires will be useful for those who are ready to do the termination with their own hands:

1. It is necessary to process the cable, remove the insulation using a special device, leaving a margin of 0.3 - 0.5 cm. If stripping was done with a knife, you should make sure that the core is not touched. If damage is found, the area will have to be removed.
2. Place a piece of insulating braid over the wire. Wipe the open part with alcohol, degrease and apply a special paste to it.
3. Set the desired section size and tip type in the matrix. Insert the tip all the way.
4. The cable cores in the straightened state should be inserted into the tip until they stop.
5. Press the crimper handles. After a characteristic click, compression can be considered complete. The handles should return to their original position.
6. Return the piece of braid to the joint and heat it with a hair dryer.

Crimping of wire lugs is performed in a certain sequence

There is an opinion (and some do) that crimping is easy and without special tools, using ordinary pliers. To a certain extent, this is acceptable, but only for small cross-section wires and, if necessary, make a temporary connection. A tight fit of the tips to the core can only be ensured by a matrix. And then the entry of air, water, and metal oxidation is eliminated, and the connection functions for a long time and reliably.

Connection Features

The technology involves two options for crimping. This is a method of local indentation and continuous compression. Copper or aluminum wires are used for work. The sleeve must also be made of these materials. There are also elements made of copper-aluminum alloy.

Since aluminum cables are prone to the appearance of oxidative films on them, the sleeve must first be cleaned and treated with special lubricants. Copper wires are also pre-treated. The use of lubricants in the process reduces the risk of possible damage to the cores. The friction force is also noticeably reduced. Pressure testing is carried out using manual or hydraulic tools. In the latter case - with a figure press. It is usually used in large industries.

How it works? The two ends of the cable are crimped until they take a round shape. Next, the core is inserted into the sleeve until it stops. It is possible to connect not exactly end-to-end. But in this case, the cross-section of all cores does not exceed the bushing. In the case of local compression, contact directly depends on the depth of the pits. The latter can be measured with a caliper. If continuous compression is used, then check the cross-sectional area. Then, when the crimping of the wires is completed successfully, it is necessary to treat the outer layer with electrical tape or elbow cloth. Next, the wire and cable are carefully laid in the junction box.

Main types and varieties of ticks

Structurally, crimping pliers can be divided into two main types - diaphragm pliers and those that work on the principle of pliers.

The second option is considered more common: when you press the handles, the tool compresses the bushing with two working planes, but, unlike pliers, there are cutouts of the desired shape on the edges, which serve as guides. This device is suitable for crimping U-shaped lugs.

The main advantage of the tool is its versatility, since the tips can be crimped from any side. The versatility ends when it comes to liner sizes: specific press jaws are designed for a small dimensional range of sleeves.

If you crimp frequently or are currently working on a large wiring project, you are more likely to crimp wires with both large and small sizes of cable lugs. Thus, you need to keep several crimpers on hand for different bushings.

There is an excellent alternative: crimpers with a set of removable dies installed on a cassette. To change, the working part of the tool is inserted into the hole in the cassette, then pulled towards you, and the matrix is ​​inside. All that remains is to insert the base into the hole with the matrix of the desired shape. Remember high-quality razors with removable blades - a similar principle works.

As for diaphragm press pliers, they allow crimping from four or six sides. The exact amount depends on the diaphragm mechanism. The full circumference of the sleeve improves the quality of the connection and ensures maximum crimp density. In addition, this device automatically adjusts to the thickness of the sleeve used, so there is no need to change dies.

But even such a tool has a drawback - you can crimp the end of one wire, since there is a closed “working head” on the other side. Using diaphragm pliers, you cannot crimp two wires instead of twisting them.

Types of connecting tubes

Crimping of wires can be carried out using connecting sleeves in several designs. The choice of connecting tube will depend on the electrochemical properties of the metal from which it is made and its interaction with the material of the wire.

There are several options for materials for the manufacture of sleeves:

• copper;
• tinned;
• combined universal;
• isolated.

Copper tubes (CM) are used for copper wires, the crimping of which cannot damage the protective layer due to its absence. The tubes cannot be used in aggressive environments.

Tinned sleeves (GML) are suitable for copper type cables used in aggressive conditions. The white protective layer covering the surface of the product fully copes with the main functions. The tubes are not suitable for working with aluminum wires due to possible contact of the protective layer, which is partially destroyed during compression, with aluminum.

Combined wire sleeves have a distinctive feature - their shape. The aluminum part is larger than the copper part. This is due to the resistance of aluminum, which exceeds the resistance of copper. During the crimping process using such tubes, wires are inserted on each side, taking into account the type of metal.

The last option for sleeves is insulated (GSI). They replace additional insulation with PVC tapes due to the presence of heat-shrinkable tubing. Their structure is similar to the structure of GML tubes, with the exception of a PVC layer that does not transmit electricity. The protective layer is quite plastic and reliable, indestructible even during the crimping process, taking the shape of a metal.

Differences in wire crimping tubes by material

Connecting sleeves are divided into several types depending on the material of manufacture. The use of different types is due to the fact that, due to the electrochemical properties of metals, some react actively with each other, which leads to oxidation of the wires and their overheating under load.

Copper sleeves

The abbreviation GM indicates that the sleeve is made of high-quality copper. Used exclusively for connecting copper wiring. The surface of the GM is not covered with a protective shell, so it can only be used in non-aggressive environmental conditions.

Tinned sleeves

Tinned sleeves are used to connect copper wires intended for use in aggressive environments. These are the same copper sleeves, only their surface is coated with a special compound that forms a white protective shell. The abbreviation is as follows - GML.

The advantage of tinning is to protect the material from electrochemical corrosion, however, it is prohibited to use GML for aluminum wiring. This is due to the fact that during the compression process the protective layer is partially destroyed, which will result in direct contact between aluminum and copper.

Connecting tubes for cores made of different materials

The installation of electrical lines, as a rule, is not complete without the use and connection of cores made of different materials. For such purposes, special sleeves are used, which are considered combined and are called GAM. The design is simple, but its peculiarity lies in the use of different materials. Two parts of the tube are welded into one, one is made of aluminum and the other of copper. The middle, the junction is equipped with a special limiter. Thanks to it, equal input of the cores is ensured on both sides.

This variety differs in shape. This can be explained by the fact that the aluminum part of the tube has a larger diameter due to the need for a larger cross-section of the conductor.

The algorithm for crimping GAM is similar to the previous methods.

What is the essence of the method?

Crimping is a method of connecting wires using special sleeves. Outwardly, they look like ordinary tubes and serve as a connecting mechanism.

The wire strands that are to be connected are inserted into the tube from two opposite ends, crimped with press pliers, and as a result, a strong and reliable electrical unit is obtained. The tube is compressed in two or three places, depending on its length and the cross-section of the switched conductors. The connected cores and the sleeve are jointly subjected to deformation. At this moment, the tube compresses and squeezes the conductive surfaces of the conductors. Due to this, the wires interlock with each other, which provides reliable electrical contact.

The junction is then isolated.

Most often, this method is used in situations where it is not possible to use another type of connection. For example, welding requires the presence of electricity so that the welding machine can be connected. When working in a small junction box, it is inconvenient to position the bolt connection, nut clamp or terminal block. And reaching up to the distribution box from the ceiling with a soldering iron is also not very convenient. It is in such cases that crimping wires using sleeves helps out.

The crimping method is most in demand:

• if it is necessary to connect wires in power lines with a high current load;
• for switching multi-core conductors;
• if it is necessary to connect large cross-section wires.

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What is crimping with sleeves?

The essence of crimping is that electrical wires or cables are connected using conductive sleeves, which are tubes made of metal. The process of crimping cables, as a result of which a strong and reliable electrical connection is created, is as follows:

1. The cores of the electrical wires, previously stripped of insulation, are inserted into the inner part of the crimp tube at both ends and must be connected.
2. Using special press pliers or ordinary pliers, crimp the sleeve around the conductor placed in it. For higher reliability, the tube is crimped in two or three places.
3. The place where the crimping is performed is isolated using TUT or electrical tape made of PVC for this purpose. If connection sleeves covered with a layer of insulation are used for crimping, there is no need for additional insulation of the formed connection.

Stages of crimping an electrical wire with a sleeve

Crimping wires with sleeves is especially relevant in the following situations:

• when connecting elements of electrical networks operated under high load;
• when connecting wires with a large cross-section;
• in cases where it is not possible to connect the wires in any other way (in particular, this method is used to connect wires in a junction box in which it is quite difficult to mount a terminal block;
• In addition, crimping sleeves are used to connect wires located at high altitudes or in conditions of limited visibility).

Crimping of wires with sleeves ensures excellent electrical contact and high mechanical strength of the connection

Let us list the most significant advantages of connecting wires by crimping.

1. The tool for crimping wires, which is mainly used as press pliers, does not need to be connected to an electrical network, which distinguishes it favorably from electrical devices with which wires are connected by soldering. Thus, crimping (or sleeve, as this process is also often called) is practically the only possible way to form a high-quality connection of wires in places where there is no possibility of connecting the tool used to the electrical network.
2. To connect wires using the crimping method, special knowledge and skills are not required. This cannot be said, for example, about soldering, which is unlikely to be done efficiently without the appropriate skills and experience.
3. Using a special tool for crimping sleeves, you can create high-quality wire connections even in hard-to-reach places, such as distribution boxes and socket boxes. Moreover, the use of the crimping method for connecting wires in socket boxes makes it possible to reduce the length of the connected contacts to a minimum, which makes it possible to increase the density of the electrical installation performed.

An important advantage of using crimping is that using this method you can successfully connect wires whose cores are made of different metals. The same soldering cannot achieve this.

Twist connection

The easiest way to connect wires is twisting. Previously, this was the most common method, especially when wiring in a residential building. Now, according to the PUE, connecting wires in this way is prohibited. The twist must be soldered, welded or crimped. However, these methods of connecting wires begin with twisting.

In order to perform high-quality twisting, the connected wires must be cleared of insulation to the required length. It ranges from 5 mm when connecting wires for headphones to 50 mm if it is necessary to connect wires with a cross-section of 2.5 mm². Thicker wires are usually not twisted together due to their high rigidity.

The wires are stripped with a sharp knife, insulation stripping pliers (ISR) or, after heating with a soldering iron or lighter, the insulation is easily removed with pliers or side cutters. For better contact, bare areas are cleaned with sandpaper. If the twist is supposed to be soldered, then it is better to tin the wires. Wires are tinned only with rosin and similar fluxes. This cannot be done with acid - it corrodes the wire and it begins to break at the soldering site. Even washing the soldering area in a soda solution doesn’t help. Acid vapors penetrate under the insulation and destroy the metal.

The stripped ends are folded parallel into one bundle. The ends are aligned together, the isolated part is held firmly with your hand, and the entire bundle is twisted with pliers. After this, the twist is soldered or welded.

If there is a need to connect the wires to increase the total length, then they are folded opposite each other. The cleaned areas are placed crosswise on top of each other, twisted together by hand and tightened tightly with two pliers.

You can only twist wire made of the same metal (copper with copper, and aluminum with aluminum) and of the same cross-section. Twisting wires of different sections will turn out uneven and will not provide good contact and mechanical strength. Even if it is soldered or crimped, these types of wire connections will not ensure good contact.

What is the joining process?

The use of terminals allows you to create reliable contact.
Before starting work, you need to purchase couplings suitable for the diameter of the wire. This figure should be exactly 2 times the diameter together with the insulating layer.

There are two types of couplings - simple and with complicated insulation. The former have a single layer of plastic, the latter are equipped with a layer of heat shrink on the surface and inside with a layer of glue and sealant.

It is worth taking a responsible approach to the choice of tool – press jaws. The best option is a modification equipped with a ratchet for fixation, which greatly simplifies the process of working with bare and insulated conductors.

Work begins by cutting the wire with wire cutters. Next, it is important to clear them of insulation to a length equal to 0.5 times the length of the sleeve. If several wires are connected on one side, first twist them. Next, the sleeve is put on and carefully healed with pliers. If heat shrink was included in the kit, put it on before crimping.

One side of the pliers is equipped with an oval sponge, and the other with the same sponges, only larger sizes. The smaller side is intended for clamping the wire insulation in the sleeve, and the second is for fixing the metal coupling.

The process of crimping wires using press pliers and lugs

To make a reliable connection, the pliers crimp the sleeve first on one side and then on the other. Next, heat shrink is installed and processed by fire from one side to the other. If the wires are connected on one side, heat shrink is applied in advance.

Standard crimping errors

There are several typical mistakes that novice electricians or those who carry out the core crimping process themselves make. For example:

1. The used sleeve has a cross-section smaller than the wire. There is never any need to reduce the cross-section of the cores and adjust it to the diameter of the sleeve. This leads to an increase in resistance and a decrease in throughput. Where there was a combination, the vein will heat up and collapse.
2. Large size sleeve. If the socket is used with a large diameter, it will not bring a strong and reliable connection. Even if you bend the wire several times, this will not lead to good performance, since the mechanical strength will drop by almost half.
3. Cutting the sleeve into several parts. When crimping a cable with a short length of exposed ends, it is inconvenient to work with pliers, and the contact area is reduced.
4. Crimping should be carried out exclusively using press jaws. Special tools were invented for this joining method. Therefore, you should not use pliers or a hammer, as this can damage both the sleeve and the cable. To prevent this from happening, it is necessary to use a tool such as press pliers, as they greatly simplify the work of crimping cable connections.

That's all I wanted to tell you about how wires are crimped with sleeves. We hope the information provided was useful and interesting for you!

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Advantages and disadvantages

There are many positive aspects to crimping:

1. The tool used to make this connection is hand-held and does not require electricity to operate. In cases where you have to work in a room where there is no voltage, crimping is the only high-quality connection method.
2. Using crimping tubes, you can connect conductors from different metals, which is a solution to the eternal problem of switching copper and aluminum conductors in one electrical unit.
3. If welding requires a specialist capable of performing welding work, and when soldering it is necessary to be able to use a soldering iron, then anyone can do crimping; you just need to try the press pliers in action once.
4. Using a special crimping tool, it is possible to make connections in any, even limited spaces. It is especially convenient when connecting wires in a socket box or box.
5. Crimping with press pliers and sleeves allows you to shorten the connected sections of wires to a minimum.
6. Due to mechanical force, the most durable contact connection is created.
7. As a result of crimping, a permanent connection is obtained that can withstand heavy physical stress when breaking.
8. Installation speed is minimal, connection quality is maximum.
9. This contact does not require any maintenance.

The one-piece type of crimping is in some way a disadvantage, that is, if necessary, it is impossible to unscrew the connection and replace one of the conductors. The sleeve can only be cut out.

Wire crimping: common mistakes

Many novice electricians or people who do not have information in the field of electrical installation often make a number of mistakes that affect the subsequent operation of the entire electrical circuit.

Pressure testing can be carried out using sleeves or tips

Installation errors:

• The sleeve cross-section is smaller than the cable cross-section;
• Sleeve of larger cross-section;
• Saving;
• Crimping without using pliers.

When purchasing crimps (sleeves), many do not take into account such an important factor as the cable cross-section. Therefore, after purchasing a crimp sleeve or sleeves, it turns out that its cross-section is smaller than the cross-section of the wire.

The main mistake that is made in this case is reducing the cross-sectional area of ​​the cable, which is completely unacceptable. This is due to the fact that at the junction of the wires, resistance increases, which leads to heating of the wires during operation. And if a device with higher power is connected to this network, the wire may simply burn out and lead to a short circuit.

The use of sleeves with a large cross-section will not allow achieving high-quality and reliable contact

It is important to understand that with this connection, the mechanical strength also decreases

In order to save on connecting elements, many divide one sleeve into several parts, thereby increasing the resistance accordingly.

The rules stipulate that crimping of sleeves must be done only with a special tool in the form of press pliers. Therefore, a hammer or pliers are completely unsuitable for this job.

This is due to the fact that using a hammer can damage the sleeve, and compressing the sleeve with pliers is not enough for good contact.

Tools for crimping

Despite the fact that it is possible to crimp wires using special sleeves even with simple tools such as pliers, a hammer or a chisel, this is not recommended. It is quite difficult to achieve the formation of high-quality and reliable contact between two conductors in this way. In addition, using such tools, you can easily damage the sleeve, which you simply have to throw away.

Manual crimping tool for cable sleeves with adjustable crimping force

Special tools allow you to obtain guaranteed high-quality electrical connections using crimp sleeves:

• press jaws, which today are available in various modifications;
• press of mechanical and hydraulic type (manual or powered by an electric drive).

Wire crimping pliers with ratchet mechanism

The main elements of the tool designed to perform wire crimping are:

• a matrix, which, acting on the sleeve with its shaped working surface, compresses it around the conductor;
• punch - a movable element that transmits pressure from the power mechanism of the tool to its matrix.

In order for the connection made using such a tool to be of high quality, it is necessary not only to correctly select the replacement matrix for a sleeve of a certain diameter, but also to apply sufficient pressure to the connecting tube.

Classification by material of manufacture

One of the main parameters, depending on which wire sleeves are divided into different types, is the material of their manufacture. The need to use dissimilar sleeves is determined by differences in the electrochemical properties of the connected wires made of different metals. So, if an inappropriate sleeve is chosen to connect wires made of a certain metal, the place of the formed contact will oxidize, which over time will lead to a decrease in its reliability in terms of electrical conductivity.

The main types of sleeves for crimping electrical wires, depending on the material from which such tubes are made, are:

• copper sleeves;
• tinned connecting sleeves;
• combined;
• isolated.

Copper

A copper sleeve, which is marked GM, is needed for crimping wires also made of copper. Taking into account the fact that the copper sleeve does not have a protective coating, it can only be used to connect wires operated in a non-aggressive environment. If you neglect this requirement, the copper sleeve will quickly oxidize and cease to perform its functions.

Copper cable sleeves must be made from copper tubes of grades M1 or M2

Tinned

To connect electrical wires operated in an aggressive environment, tinned copper sleeves for crimping are used, which are marked GML. In order to protect the main material of their manufacture - copper - from electrochemical corrosion, GML sleeves are coated with a special compound.

This is explained by the fact that part of the protective coating of such a tube is destroyed when it is compressed, which will lead to contact between aluminum and copper and, accordingly, to the development of electrochemical corrosion.

Connecting sleeves type GML, made of electrical copper with a tin-bismuth protective coating

Combined

Quite often, when installing electrical networks, it becomes necessary to connect wires whose cores are made of different metals. To solve such problems, combined type sleeves have been specially developed and are successfully used. The design feature of such crimp tubes, which are marked GAM, is that one half of them is an aluminum connecting sleeve, and the second is made of copper. At the junction of two such tubes, which are connected to each other by welding, there is a special limiter. It is necessary in order to prevent contact of two dissimilar wires inside the sleeve itself.

Adapter cable sleeve aluminum-copper 16/10 sq. mm

Another design feature of combined crimp tubes is that the part of them, which is the aluminum connecting sleeve, has a larger diameter than the tube intended for copper cables. This design feature is explained by the fact that aluminum, when compared with copper, has greater electrical resistance, therefore the wire made from it, which will be connected to the same electrical network with a copper conductor, must have a larger diameter.

The crimping itself using combined sleeve clamps is performed according to the same algorithm as the procedure with sleeves of any other type. However, it is necessary to carefully ensure that dissimilar wires are inserted into a tube of the appropriate metal.

Isolated

Among the crimping tubes used for crimping electrical wires, the category of insulated connecting sleeves is distinguished. The use of the latter eliminates the need to perform additional insulation of the contact area formed with their help. In terms of their design, insulated sleeves are the same tinned copper tubes, the outer surface of which is covered with an insulating layer of fairly durable and at the same time plastic PVC. Due to the mechanical properties of such a protective layer, sleeves of this type can be successfully crimped without compromising their original characteristics.

Fully insulated connection sleeves

Insulated sleeves for hermetically sealed connection of SIP wire cores

Crimper for crimping tips: design specifics, application

The operating principle of crimpers for crimping wire lugs is the same as that of double-jaw pliers. The difference is that the latter clamp the sleeve, and the crimper clamps the plugs. More precisely, crimping is not performed in its standard sense, but the contacts are shifted, which leads to tight pressing. This tool is designed to work with twisted pair cables.

Cable connection always begins with stripping the insulation from the ends of the wires

Before performing crimping with a crimper, be sure to evenly trim the untwisted conductors. If this is not done, a uniform position in the connector will not be achieved, and this will affect the quality of the crimp. You can do this with regular wire cutters, but this does not always give the desired result.

Many models of pliers for crimping Internet cables are equipped with special cutters. They are blades that close tightly when you press the handles of the tool.

Important! Before cutting, the straightened wires must be placed in the sequence required for connection (based on color).

There are many types of crimpers. The operating principle of all models is the same, but there are differences in connector standards. The body of the cable crimping pliers must contain symbols indicating the purpose of the tool. For example, RJ 45 is designated as 8P. This indicates the standard and maximum number of pairs. RJ 11 – 6P, the maximum number of pairs does not exceed 6.

A typical crimping crimper has comfortable plastic handles and a steel body and jaws.

Crimping pliers for crimping RJ 45 wire lugs

RJ45 connectors are one of the most used in the field of computer networking. RJ stands for Registered Jack, a standardized network interface. The body of this device is much larger than RJ 11. The latter cannot be used for computer connections; it is used when laying telephone cables. The internal contents and operating principle of these two types of connectors are almost identical.

Crimping pliers for RJ45 cable lugs are selected in accordance with the markings. As for the general requirements, you should pay attention to the following indicators:

1. Weight. A small one most likely indicates the use of insufficiently strong materials for manufacturing, so you should not count on a long service life. Excessively heavy ones will contribute to rapid hand fatigue.
2. The shape of the handles. It should be ergonomic and easy to grip.
3. Presence of defects. Traces of dents and other mechanical damage may be a consequence of improper assembly. It is worth paying attention to the contact lines of the blades and jaws: even minor deviations will affect the quality of the crimp.

Among the most popular models of manual press jaws for twisted pairs is the Hanlong HT-500. The tool is designed for both RJ45 connectors and RJ11 and RJ12 options. The crimper is equipped with blades for cutting and stripping. The price of the product is 1250-15000 rubles. The model should be classified as professional.

Crimping pliers for RJ45 cable lugs are selected in accordance with the markings

Inexpensive pliers 5bites LY-T568R are quite in demand. They are also designed for three types of connectors and have blades. The products are lighter, weight – 340 g, less durable (according to user reviews on social networks). They can be purchased for 450-500 rubles.

How to connect electrical wires by soldering

Connecting electrical wires by soldering is very reliable. You can solder untwisted wires, but such soldering will be fragile due to the fact that the solder is a very soft metal. In addition, it is very difficult to lay two conductors parallel to each other, especially when suspended. And if you solder on some kind of base, the rosin will stick the soldering area to it.

A layer of rosin is applied to the pre-tinned and twisted conductors with a soldering iron. If another flux is used, it is applied in the appropriate manner. The power of the soldering iron is selected based on the cross-section of the wire - from 15 W when soldering headphones to 100 W when soldering twisted wires with a cross-section of 2.5 mm². After applying the flux, tin is applied to the twist with a soldering iron and heated until the solder completely melts and flows into the twist.

After the soldering has cooled, it is insulated with electrical tape or a piece of heat-shrinkable tubing is put on it and heated with a hairdryer, lighter or soldering iron.

When using a lighter or soldering iron, be careful not to overheat the heat shrink.

This method reliably connects wires, but is only suitable for thin wires, no more than 0.5 mm², or flexible ones up to 2.5 mm².

How to choose the right wire and tip

First, you need to find out what cross-section of wire you will be crimping. This can be done by following the inscriptions on the core insulation, or using a caliper. Further, when choosing certain sleeve tips, you can be guided by the color marking of their insulated skirt. Each color must correspond to a specific section and size of the tip sleeve.

True, there are also manufacturers who don’t bother with this and produce single-color products of different sections. After choosing, be sure to physically check how tightly the wire fits into the sleeve or tip. In this case, there is absolutely no need to twist the wires before inserting them into the tip.

The tip at the entrance has a special skirt that will help you put it on even a slightly fluffy wire. In addition, this skirt acts as an insulation retainer. You can compare how many kinks in different directions the wire will withstand and without a skirt. As you understand, the result will not be in favor of the latter option.

Another important point that needs to be remembered: many wires are manufactured not according to GOST, but according to their own technical conditions.

It often happens that a 2.5mm2 wire easily fits into a tip with a cross-section of 1.5mm2. Therefore, choosing from tables is, of course, good, but you can’t do without practical fitting of the sleeved part and wire.

Terminal block connection

A development of the bolted connection is the terminal connection. Terminal blocks come in two types - with a rectangular pressure washer and with a round one. When using a terminal block with a pressure washer, the insulation is removed to a length equal to half the width of the terminal block. The bolt is released, the wire is slipped under the washer and the bolt is clamped again. On one side, you can connect only two wires, preferably of the same cross-section and only flexible or only single-core.

Connecting to a terminal block with a round washer is no different from using a bolted connection.

The connection of the wires is reliable, but cumbersome. When connecting wires with a cross-section of more than 16 mm², the connection is unreliable or the use of lugs is necessary.

Manual press pliers - how crimping occurs

When connecting wires using the crimping method, the electrical contact that is created between them is rightfully considered one of the most reliable. Manual press pliers for crimping PK-16 sleeves, produced by the KVT company, are a compact crimping tool that allows you to perform this work efficiently.

To perform crimping you must do the following:

1. - strip the insulation from the wires that need to be connected;
2. — the stripped wires are threaded into a sleeve, the diameter of which is equal to the sum of their sections (the sleeve must be made of the appropriate metal);
3. — crimp using the above tool;
4. — insulate the sleeve with electrical tape or heat-shrink tubing.

At first glance, the procedure is quite simple, but it is the use of the correct press tongs that is the most important nuance. Therefore, the choice of such a tool must be balanced and deliberate. After all, not everyone can squeeze ordinary hand press pliers with a force sufficient for high-quality crimping.

The model of manual press tongs that we will consider in this article are excellent for solving the problems described above. These are hand press pliers PK-16 from.

How to connect wires by crimping

Another way to connect wires is crimping. This is a method in which a copper or aluminum sleeve is placed on the wires or cables to be connected, and then crimped with a special crimper. For thin sleeves, a manual crimper is used, and for thick ones, a hydraulic one is used. This method can even connect copper and aluminum wires, which is unacceptable with a bolted connection.

To connect using this method, the cable is stripped to a length greater than the length of the sleeve, so that after putting on the sleeve, the wire sticks out 10–15 mm. If thin conductors are connected by crimping, then twisting can be done first. If the cable has a large cross-section, then, on the contrary, in the stripped areas it is necessary to align the wire, fold all the cables together and give them a round shape. Depending on local conditions, the cables can be folded with the ends in one direction or in the opposite direction. This does not affect the reliability of the connection.

A sleeve is tightly placed on the prepared cables or, when laid in opposite directions, the wires are inserted into the sleeve from both sides. If there is still free space in the sleeve, it is filled with pieces of copper or aluminum wire. And if the cables do not fit in the sleeve, then a few wires (5–7%) can be cut off with side cutters. If you do not have a sleeve of the required size, you can take a cable lug by sawing off a flat part from it.

The sleeve is pressed 2–3 times along its length. The crimping points should not be located at the edges of the sleeve. It is necessary to retreat 7–10 mm from them so as not to crush the wire during crimping.

The advantage of this method is that it allows you to connect wires of different sections and from different materials, which is difficult with other connection methods.

MMA welding: features

Creating a permanent connection of stainless steel using simple electrodes is carried out in several stages. First, all rust and excess inclusions on the surface of the product are removed. If there are edges over 4 mm, the master will cut them with a file, which will ensure effective fusion of the part. If the product has thin dimensions, it is necessary to move the two edges of the workpiece tightly together. According to GOST 10052-75, OZL-8, TsL-11, and UONI brands are suitable for stainless steel. If you have information about the grade of metal according to GOST, you can select the required consumables.

Procedure:

1. Workpieces with a width of more than 7 mm must be heated to 150 °C.
2. After preparation, the finished tool is brought up and lightly struck at the site of the future seam several times. This way the welder activates the electric arc.
3. The further operation takes place under the influence of the short arc effect. The welder slowly passes the entire section of the seam along the line with smooth zigzag movements.
4. At the end you need to make a lock to prevent seams.
5. After cooling, you can remove the slag and weld spots and then polish the seam.

To create a seam, corrosion-resistant and heat-resistant electrodes are required. Such electrodes include OZL-6 with characteristic heat resistance. ANO-27 rods are also beneficial for welding the necessary structures and parts. The seam perfectly withstands low temperatures.

Features of using NShVI tips

Electrolytic copper is used to make pin sleeve lugs. There is insulation on the back of the product. To prevent corrosion from damaging the metal, copper is treated using galvanic tinning. The size of these tips varies between 0.25-150 mm.

When crimping NShVI, time is significantly saved, which simplifies the process of connecting electrical devices. The tips are suitable for household use. They are designed for crimping multi-core wires of any type. Manufacturers produce two types of NShVI. Some lugs are used for crimping one wire, while others are designed for two.

Products are marked as follows:

1. Single - the first digit of the marking indicates the section size, and the second displays the length of the contact part.
2. Double - the number “2” in brackets indicates that this tip is intended for splicing two wires, and the next number means what the cross-sectional size of each of them is.

The sizes of NSHVI crimp lugs range from 0.25 to 150 mm

It is desirable that the size of the shank in the tip be slightly larger than the cross-section of the wire, i.e., its bare wires. So, for a 1.25 mm cable, you should purchase an NShVI with a cross section of 1.5 mm.

Basic rules for crimping wires with sleeve-type lugs

You can connect wires efficiently using a lug at home, without professional skills and knowledge. To do this you need to adhere to the basic rules:

1. Select the correct type and size of wire lug for crimping.
2. Clean the conductors thoroughly and correctly.
3. Use only specialized tools for work.
4. Follow the crimping technology exactly.

Typically, the insulation on the wire is removed taking into account the size of the contact part of the tip. After stripping, the end of the core should coincide with the edge of the sleeve. To achieve this, you need to add 2-3 mm to the length of the cleaned area

It is very important to choose the correct tip size. In order not to make a mistake, you need to be guided by the color markings in which the insulating cuffs are painted

To crimp wires with ferrules, you must use only special tools

There are some subtleties when working with insulated connectors. It is imperative to ensure that the insulating material on the wire goes all the way inside the cuff and is completely covered by it.

Preparatory work is carried out in the following order:

1. The veins are cut strictly perpendicularly.
2. To remove the insulating layer from the cores, it is necessary to take into account the size of the shank and the increase.
3. If the conductors are copper, the oxide film must be removed from their surface. To do this, the exposed area is degreased and then lubricated with technical grade Vaseline.
4. If the shape of the cores is sectoral, you will have to round them.
5. If the wire cores are made of aluminum, this metal must be cleaned to a shine. After this, the bare area is treated with quartz-vaseline lubricant, which will prevent the appearance of an oxide film.

How to connect wires by crimping in a junction box

In distribution boxes, the most common task is to route a 2.5 mm2 line into several directions. If copper wires are used, then the connection requires sleeves for crimping copper wires and special press pliers.

Let's look at how to crimp wires with sleeves in a distribution box; for example, let's branch the cable in the distribution box in three directions.

First, the insulation from the wires is cleared to a length corresponding to the length of the sleeve. The stripped ends of the wire are inserted into the sleeve very tightly so that there are no voids.

If they. However, it turned out that often when connecting three or more wires, it is necessary to “stuff” them with pieces of cores of the same wire, the length corresponding to the length of the sleeve.

I would like to draw your attention to one very important point. If you compress several conductors into one sleeve, with a standard cross-section of wires and sleeves it will not be possible to pack the sleeve tightly; there are always voids left in it and these voids must be filled

To do this, you need to “finish off” the sleeve with several more pieces of the same wire. This will allow you to create high-quality and reliable contact at the crimping site.

Crimping of wires is carried out using two or three presses in different directions (to do this, the press pliers just need to be turned 180 degrees).

It is especially important to remember that the wires must not be twisted before connecting with a sleeve. For the specified brand of wire, when connecting four branches, another sealing piece of wire and a sleeve with a cross-section of 2.5 mm2 are required

When the sleeves are put on and tightly finished off with pieces of wire, you can begin crimping. For this I use hand press pliers PK-16.

In order for the sleeve to be securely pressed, we do two presses along the edges of the sleeve (at the beginning and at the base). We do presses in opposite directions.

Crimping of wires is performed using GLM-10 sleeves. During operation, the working area of ​​the pliers must correspond to the size of the sleeve.

The photo clearly shows that the sleeve is compressed with two opposite presses. This allows you to improve the quality of contact at the junction.

The ends of the wires extending outward are cut with pliers to fit the edge of the sleeve.

The entire connection is insulated with a heat-shrinkable tube, the length of which is selected so that it extends 1 cm beyond the outer cut of the sleeve and extends onto the insulation by 1.5 cm. If you don't have heat shrink tubing, you can use electrical tape.

We heat the heat-shrinkable tube placed on the sleeves using a hairdryer. After compressing the tube, the connection points are reliably insulated.

After insulation, carefully lay the wires in the junction box and close the lid. All our wiring connections are done.

Tip material

Another relevant point in choosing a tip is the material of manufacture. When purchasing, make sure that they are selling you copper or tinned tips. To do this, it is enough to first purchase one tip and file it with something foreign.

With copper material, especially if high-quality copper is used, the cut will be reddish in color. If ordinary copper alloys are used, which is most often the case, then the cut will be a pale yellowish color.

When exposed to air, copper may darken and lose contact quality. Copper tinning is a long-known method that makes the contact durable and reliable.

Advantages of crimping wires with lugs

• the crimped end of the wire is considered airtight
• the ferrule sleeve prevents individual wires from being damaged or excluded from contact
• tinned tip surface – reliable protection from environmental influences

Advantages and disadvantages

Like any type of connection, crimping has its positive and negative sides. When deciding on the type of connection, you should rely on many factors that make it impossible to use one or another method. Among the advantages of crimping:

• High degree of connection reliability. Only welding or soldering is more reliable than this method;
• Manufacturability of the process. The method takes a very short amount of time and does not require its performer to have any special knowledge in electricity, metals, and so on;
• The pressed sleeve does not require any attention and maintenance throughout the entire life of the cable;
• Does not depend on the availability of power and can be performed even in places where electricity has not yet been supplied.

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Performing crimping

But this connection method has quite a few disadvantages. The main ones are:

• The need to have a special tool with you - press pliers or a crimper. You cannot replace them with ordinary pliers;
• The need to constantly carry with you different sleeves for each type of wire or cable, to distinguish between them;
• High costs for raw materials in the form of metal tubes and tools;
• The connection is cumbersome compared to the same methods of welding and soldering, which can result in a seam equal in diameter to an insulated cable.

Important! The method itself is a disadvantage because it is not removable. If necessary, you cannot take and unscrew the connection, and then screw it back.

Various crimp sleeves