What is a broach in electrics. The most effective ways to stretch a cable in a HDPE pipe

In accordance with the rules for the installation of electrical equipment, corrugated pipes are used when laying low-voltage networks or electrical wiring. This is due to the fact that the corrugation is a pronounced dielectric that protects the wiring from mechanical and thermal effects.

What is corrugation

Cable installation in corrugation

Corrugation, despite its simple design, is considered one of the most useful and sought-after inventions of mankind. Visually, it is a pipe with a ribbed surface, which simultaneously gives it rigidity and flexibility. Corrugations are made from various materials, the most popular are metal, aluminum, and plastic pipes.

The corrugation comes in different diameters, the indicators range from 10 mm to 2 m. This product has a wide range of applications.

Scope of corrugated pipes

Corrugation allows you to lay electrical wiring of any complexity and length with the least number of turns and joints

Corrugated pipes are widely used in various industries, as well as for domestic purposes.

• computer networks (white color);
• general electrical wiring (gray);
• connection of electrical appliances, household appliances (brown);
• laying of telephone lines (green);
• external wiring (red);
• for connecting heating systems, underfloor heating (blue);
• gas supply systems (yellow).

For electrical cables, special electrical corrugations made of polyvinyl chloride are most often used.

How to run a wire into a hose

Correct connection of the string with the wire installed in the corrugation

1. Remove the end of the wire (a kind of cable or string) from the hose and connect it to the cable to be installed. A hole is made in the winding of the wire, a thin wire is pushed through it and securely fixed by twisting.
2. The hose is leveled along the entire length, only after that you can proceed to the cable plant into the corrugation.
3. One worker firmly holds the end of the pipe from which the cable is wound, and the second pulls the wire from the back. This approach allows the wire to be pushed through efficiently.
4. A fully extended wire must be wound to the pipe to prevent the structures from moving relative to each other.

There are cases when the wire gets stuck inside the corrugation. This is due to the weakening of its tension or the formation of bends. Until the end of the pulling process, it is important to monitor the condition of the hose.

How to stretch the wire

The scheme of pulling the wire into the corrugation

You can run electrical cables along walls or ceilings using special clips. Their diameter is selected in accordance with the cross section of the corrugation. This method is more common, because it securely fixes the pipes and has an attractive appearance. In hidden places, it is preferable to use dowel-screws or metal staples.

When laying pipes, the joints are connected using a budgetary connecting element - a coupling. If the wires are not insulated in this section, the place of attachment to the pipe coupling can be sealed with sealant. To pass through the walls, special perforated sleeves are used, which, if necessary, are also treated with sealant.

When pulling the cable in the corrugation, it is important to avoid bends that exceed the allowable radius.

Installation of electrical wiring in the corrugation in an open way

Installation of open wiring in a wooden house

Installation of corrugated pipes includes several stages. The algorithm for installing electrical wiring in the corrugation in an open way:

1. To fix the hose, special clips made of high-quality plastic are used. They are characterized by different sizes, the choice will depend on the diameter of the pipes used.
2. Clips are attached to surfaces with an interval of 30-40 cm. This is done using dowel screws or self-tapping screws. The choice of details depends on the material from which the surface is made, for example, wood, concrete, brick, etc.
3. For reliable fixation, the corrugation is pressed into the clip until a characteristic click appears. If the clips were chosen correctly, the probability of spontaneous loss is excluded.

At the design stage, laying a schematic wiring path, you need to take into account the following important points:

• The maximum and allowable radius of the corrugation is 90 degrees. The smoother the angle, the better.
• Turns should not be located close to each other, the optimal distance between them is 4-5 meters. If this is not possible, for safety reasons, the wiring is additionally equipped with a junction box.
• The maximum length of an individual section is 25 meters, the allowable number of turns is 4.

How many wires can be laid in one corrugation

Selection table for corrugated pipes depending on the number of wires and cross-sectional dimensions

According to the rules for the installation of electrical installations, it is required to lay the main and backup cables, as well as emergency and working lighting wires through different channels.

An approximate calculation of how many cables can be laid in one corrugation:

• With a diameter of 16, 3 cables fit.
• If it is 20, 4-5 will fit.
• Diameter over 25 accommodates 5-6 cables.

The exact amount is calculated on the condition that the length of the pipe is at least 35 meters.

If the integrity of the metal structures is damaged, they are soldered with a special acid. If the integrity of the plastic corrugation is broken, the holes are welded with polyethylene.

The advantages of corrugations are affordable cost, light weight, which greatly simplifies the process of transportation and installation, high resistance to thermal and mechanical stress, long service life.

As a rule, there are no difficulties in choosing and installing corrugated pipes. During work, personal safety precautions must be observed; when working with electrical cables, it is important to de-energize the room and check the voltage in the cores.

There are a huge number of different terms and verbal expressions inherent in a certain professional field of activity.

For example, all specialists involved in the construction of various electrical, telephone and intercom systems know what a cable pull is.

This is exactly the device that cannot be dispensed with when laying wires through various voids / pipes or switchboard cabinets. By the way, in another way this device is called an ultrasonic cable puller and its main purpose is to pull cables or wires into various communication channels.

At first glance, this design is very strong, flexible and unaffected by the external environment. In our today's article, we will try to reveal in more detail the topic of using cable pulling, as well as all existing types of this design.

Where is cable pulling used?

It should immediately be said that the scope of cable pulling is quite extensive. First of all, the design is used to create complex lines or systems in hard-to-reach places. This device helps to overcome various types of voids through which the cable is laid, such as: pipes, boxes, channels, metal hoses, floor panels.

The main function of ultrasonic testing is the introduction of the cable into the necessary environment for its full-fledged operation. Basically, broach is used in the following works:

• creation of an electrical wiring line;
• equipment for various types of communication, both telephone and computer;
• installation of intercom networks;
• formation of video, audio systems, as well as security systems;

It should be noted that the required temperature regime for the full operation of the product is -15C to +50C. The cable puller is able to last at least 1.5 years, but this indicator may vary depending on how aggressive the environment in which it is located and the intensity of use of the system. Of course, replacing wiring is a painstaking and time-consuming process, which is why pulling a cable allows you to do it much less often.

Types of cable broaches

Cable broach is classified according to the material of manufacture of its inner part, which protects the cable from an aggressive external environment. Thus, distinguish:

• fiberglass;
• steel;
• nylon.

Each type has its own characteristics and therefore is used in different situations. For example, fiberglass broaches have the greatest rigidity due to everything they practically cannot exist in a bent state and tend to straighten all the time. That is why you need to handle the material as carefully as possible, because due to bends, the material can be damaged. To a greater extent, fiberglass is suitable for pulling cables through small holes and stretch ceilings.

Steel broach is formed by metal wire or metal strip, which is packed in a nylon sheath. This material is responsible for providing better bending strength and preventing tensile deformation. This type of device is perfect for laying the cable cable through the L-shaped turns in the channels.

As for nylon cable broaches, they are great for laying cables through closed channels (pipes, various boxes). They have great flexibility and can coexist safely with other live cables.

As for cable broaches in general, it should be noted here that the device has recently undergone significant improvement.

The material from which it is made - polyester fiber, has a huge number of undeniable advantages, namely strength, wear resistance and quick adaptability to the environment. The latest cable puller has an exceptional property of preventing any friction. It is also absolutely resistant to ultraviolet radiation, all kinds of adverse weather conditions, to alkaline and acid solutions.

Cable broaches made of polyester fiber do not corrode over time and have good insulating properties. And thanks to easy color marking, they provide easy size identification and navigation in cable ducts, pipes,
tunnels.

That, in principle, is all the necessary information about cable broaches that you need to have. It is worth saying that this is far from all the information about this device, but it is sufficient to have an idea of ​​what cable pulling is, where it is used and what its practical purpose is.

If you want to understand this topic on a more professional level, then, of course, additional literature will not harm you. And we, in turn, wish you good luck and hope that the service life of this structure will not be 1.5 years, but will serve you for at least 10 years.

My favorite broke (and happily found on the street!) fiberglass broach, which has been in many battles with holes, pipes and channels in the walls in the process of laying networks and even power cables. I was looking for a replacement for her for a very long time, and somehow I found one that more or less meets my nitpicking and requirements. I will try to express my thoughts on this topic in the form of a short review.

What is there anyway cable pull? This is usually a flexible, durable and indelible round structure, with the help of which soft and delicate cables are pulled into communication channels, boxes, corrugations and other similar things. The simplest application example broaches- these are Internet users who pull a twisted-pair cable from floor to floor: a low-current riser is usually clogged with other cables and wires, a twisted-pair cable is rather soft and it is very difficult (and sometimes impossible) to push it through this mess. And the rigid (and at the same time flexible) broach is perfectly pushed in and, due to its small diameter, passes through a bunch of cables perfectly. Then a twisted pair is tied to it and pulled.

In total, of those that I came across, there are three main types of broaches, classified according to the material from which its inner part is made:

• Fiberglass broaches. They have the greatest rigidity (and, apparently, the price too), and withstand all the tests of the form "you need to stick it into a small hole clogged with dirt and debris on the other side under a false ceiling." Cope with a bang in the most difficult situations. Also, due to the fiberglass structure, they tend to straighten up. This allows you to use it when laying cables in false ceilings such as Armstrong: the broach twitches and pushes - since it goes almost in a straight line, you can immediately push it five meters, open the plate and catch it there. And all this can be done by one person. Here () we just pulled the cables with such a broach. Minuses This broach is that fiberglass is a fragile material and if you bend it under a small radius, step on it, it will break. And now let's imagine: we tighten the twisted pair cable into the apartment, and there is almost an L-shaped turn. The cable does not climb ... let's pull harder - trrrrak! Minus stretch!
• Steel broaches. It feels like something in between (the price is also average - about 600-900 rubles per 10 meters) between fiberglass and some kind of minimum necessary for work. Steel broach consists of a steel tape or wire wrapped in a nylon sheath (nylon is a slippery material and this property is used in the manufacture of broaches). Due to steel, it turns out to be stronger than nylon in bending and stretching, but at the same time it has greater flexibility in the longitudinal direction, which probably will not allow it to be used as fiberglass when passing cables under ceilings. On the other hand, this flexibility will be useful when passing L-shaped turns in the channels.
• Nylon broaches. I really don't know why they release them. She has only one plus - the price (150-300 rubles). They are made of pure nylon and do not straighten at all - it can be useful for complete beginners who have problems with money. It can be used for pulling only in closed channels: boxes, pipes, and can be a metal hose, as it also has a flexible head. As soon as I bought it for myself, I was immediately upset, and it has been lying around idle since the summer.

Estiare steel broach (nylon coated)

So, here's what I bought. I bought it in the Shop220.Ru store, hitting it from a search. Description of the broach from the store -. While driving home, I examined the packaging and was inspired by the description of possible additional accessories: here you have a device for gripping the broach itself (so as not to pull with your hands), and a special spring for quickly clamping cables and even gel lubricant (BDSM?! ;))! It's also cool that all these devices are simply screwed onto the main part of the broach.

So let's unpack the box. A bag with standard accessories is glued from the inside with adhesive tape, which caused my question to the sellers: “Is there anything in the kit at all?” - since nothing was shaking and dangling by ear while I was buying it (but the sellers, after the question of broach, greeted me with the question: “Oh! Do you connect the Internet, right?”) :) There are two accessories: a flexible head and a tail for attaching a pulled cable.

The broach itself is heavy and durable in appearance, worth the money and well done. I also liked the idea with interchangeable screw-on lugs: for example, using a flexible head, push two meters of this broach into a metal pipe, and then, unscrewing the flexible head, put on the tail, attach the cable and pull the entire structure back, instead of pulling everything out 10 meters (Yes, yes! These steel broaches start from 10 meters in length).

As for self-flattening, I was a little upset - it does not straighten as quickly and strongly as fiberglass, but at the same time it has enough flexibility for acceptable work. I immediately decided to test it in the “case”: I scattered it around the apartment - in the photo below it straightened itself like this, and pushed it into a relatively clogged channel from the apartment to the stairwell. A little effort - and the broach came out on the other side. On this, I recognized such synthetic tests as valid, collected it and postponed it until the first large order - there we'll see how it is in this work.

A broach, or UZK (cable laying device), is a highly specialized installation tool that is used in the installation of electrical, computer and telephone systems. The cable puller allows you to pull the wire through hard-to-reach places where it begins to bend, so it does not go through on its own. In this case, the probe is first installed, after which a wire is attached to one of its ends. The broach is removed, while pulling the cable. The peculiarity of ultrasonic testing is greater rigidity and a tendency to level out, which allows for controlled installation through voids, boxes and pipes.

What is cable pull

A broach can be used to drag electrical or other types of wires into communication channels. The device is a rod twisted into a bay, which is easily straightened. Inside it is a cord that forms an elastic rod. The reinforcing fibers and radial threads that surround the core make the structure flexible and rigid enough to overcome complex voids. At the same time, the probe is tear-resistant, therefore it is able to drag even a thickened cable or wire, which has a large mass, behind it.

The outer coating of the broach is resistant to abrasion. This reduces the likelihood of damage to the straightened rod during operation. Despite this, with intensive use of the ultrasonic device, it may well wear out. If you use the device professionally and daily, then the service life on average does not exceed 2 years. In many ways, it depends on the materials of manufacture.

Broaches are usually marked with two numbers, between which there is a fraction. For example, the inscription on the probe “9/80” means that the diameter of the broach is 9 mm and the length is 80 m.

Where is broach applied?

The cable puller is used to carry out the installation of the wire through hard-to-reach places, which are a long void, such as:

• Pipe.
• Box
• Channel.
• Corrugation.
• insulating sleeve.
• Roof space.
• Fixed wall panels, etc.

Basically, broaches are used when it is necessary to lay wires through a previously created structure, with existing voids for installation, which cannot be disassembled to manually lead the wire without additional devices. Similar situations are encountered when laying telephone or computer communication lines in old houses where they did not exist before. Broaches are also professionally used by installers of intercoms, video surveillance and alarm systems. With the help of ultrasonic testing it is possible to lay wires above suspended ceilings or under flooring.

How to work with a broach

To carry out cable installation using a broach, it is first laid through the cavity where the wire is to be installed. The end of the ultrasonic device is inserted into the hole into which the cable should go. The probe is then pushed through the entire mounting space until its end exits on the other side. In this case, it is quite possible that you will have to tinker, especially if the cavity has small bends and irregularities. The more of them, the more difficult. Due to the fact that the straightened bar retains sufficient flexibility, it can go around obstacles and straighten further as it goes.

As soon as the cable puller comes out of the back of the cavity, a wire is attached to its protruding end. For this, a special ferrule is used, which securely fixes the cable, giving the impression that the extension wire becomes part of the probe.

Once the cable is fixed, all that remains is to pull the broach back from the side from which it started into the empty cavity. As it is pulled out, the cable will be tightened. As soon as the probe leaves the cavity and the end of the wire appears, the broach is disconnected. It remains to twist, solder or otherwise connect the wire to a common trunk.

If you immediately try to pull the wire through the cavity, then in most cases this will not give any result, since it does not have the necessary elasticity and will constantly rest against something. Also, the cable has a big drawback, namely the memory effect. When unwinding from the bay, he tends to dodge back into the rings. The same will happen in the cavity if it is wide enough. The broach does not have this effect, so even if it has been kept wound on a reel for years, it remains smooth and well controlled when unwinding.

Types of broaches depending on the material of manufacture

There are 3 types of broach materials:

1. Steel.
2. Fiberglass.
3. Nylon.

Steel It is a metal wire, which is covered with a nylon sheath on top. Such a system is resistant to stretching and can withstand heavy loads if it is necessary to drag the cable through hard-to-reach places. Such systems cope well with L-shaped turns and standard cable channels.

fiberglass broaches have high rigidity. They are capable of straightening even after many years of storage in a twisted coil. This probe is great for when you need to go through a straight line. Fiberglass is a rather brittle material, so if you have to make a sharp bend, then under tension the probe can crack and break off.

Nylon probes are used when it is necessary to penetrate closed channels where maximum flexibility is needed. This material is a dielectric, so it can work even in those channels where there are live elements.

Ultrasound equipment

The cable puller has a headband in the form of a tip at one or two ends. A wire is attached to it after the probe passes through the cavity in which it is necessary to carry out installation. The headband is threaded, so the connection with the wire is reliable and the possibility of detachment during the tightening process is excluded. Sometimes a loop or stocking is used instead of a standard headband.

A short, thin storage probe is usually coiled. A longer coil is wound on a reel. The broaches used for thick power cables are supplied on a reel with a trolley, as they are quite massive and heavy.

How to choose

In order for the cable broach to be exactly suitable for the required purpose, when buying it, you should first of all focus on the length. If it is necessary to carry out the installation of wires through cavities 20 m long, then it will not be possible to do this with a shorter probe. It is advisable to always try to choose a broach with a margin. If several probes are subsequently connected together with a cable end cap, the controllability of the resulting rod will be worse because the material will become inhomogeneous.

Also important is the thickness of the broach. It is desirable that it corresponds to the diameter of the wire that will need to be dragged. Theoretically, you can get by with a thin probe using a thicker cable, thanks to the use of adapters for the tip, but dragging a heavy cable with a light rod is at least inconvenient, and sometimes impossible.

Installation of the cable in the corrugation is most often carried out during the conduction, as well as in the floor screed. Also, a self-extinguishing corrugated pipe is used during electrical work in a wooden house. It will be quite problematic for a person without experience to thread the conductor, because. its end can cling to the inner walls of the corrugated pipe. In fact, the pulling technology is not difficult, so if you do not know how to stretch the cable in the corrugation, we recommend that you read the instructions below.

Mounting technology

To make the information easier to perceive, we will provide it step by step:

Overview of the entire event

That's actually the whole installation technology. As you can see, pulling a wire or cable through a corrugated pipe is not exactly difficult. The last thing left is to fix the corrugation on the clips. However, we provided the most successful situation. There are more difficult cases when it is rather problematic to stretch the conductor, for example, if there is no broach. Below we will consider all force majeure situations.

Read about what they are in the article we referred to!

Non-standard cases

The first and most common situation is when the string is pulled away from the conductor due to strong tension. In this case, it is recommended that the part of the corrugation that has already been threaded be cut off and left, then reconnect the wire to the end of the cable and finish the broach. Two pieces of corrugated pipe are then connected with electrical tape.

Pulling the wire through the corrugation, if there is no broach, is also not difficult. It is enough just to bend the end of the conductor by 180 ° and insulate it so that it does not cling inside the pipe, and then insert the product to the entire desired length. This technology is clearly demonstrated in the video below:

How to start a wire without a probe

If you have little space in the apartment and you need to thread a long piece of corrugated pipe yourself, for example, 30 meters, it is not always possible to do it in the room without experience. In this case, it is recommended to first connect the cable to the string, then go out to the entrance and on the top floor to the railing, fix the free end of the wire. After that, stretch the corrugation until the problem is solved. Or use the Health disc as shown in the following video (second minute):

Sometimes it becomes necessary to stretch the conductor in a corrugated pipe along the ceiling, or rather inside a suspended plasterboard structure. It is quite difficult to do this, because. if the sheets are already sewn up, installation must be carried out through the strobes under the lamps. In this case, an ordinary string will help to get the corrugated pipe through the ceiling. In the video tutorial, the masters clearly demonstrated the essence of the work:

How to run a corrugated hose through a plasterboard ceiling

Well, the last situation that I would like to describe is the laying of a cable with rubber insulation in the corrugation. The difficulty lies in the fact that during the broach there is a strong friction between the walls of the corrugated pipe and the insulation of the conductor. As a result, even the wire does not facilitate the process, and if there is no broaching, in this case it is generally unrealistic to complete the installation. A special lubricant comes to the rescue, for example Wire Pulling Lubricant from 3M, with which you can quickly pull the cable through the corrugated pipe. The cost of such a lubricant is a little high, however, if you often do electrical work, we recommend purchasing it, because. one bottle lasts a long time.

That's actually all the information that we wanted to provide. We draw your attention to the fact that it is better to tighten a cable with a cross section of 3 * 1.5 mm 2 into a pipe with a diameter of 16 mm. At the same time, for a section of 3 * 2.5 mm 2, a diameter of 20 mm is needed. Now you know how to stretch the cable into the corrugation with your own hands and what to do if there is no broaching!