The Tesla coil is a high-frequency resonant transformer without a ferromagnetic core, with which you can get a high voltage on the secondary winding. Under the action of high voltage in the air, electric breakdown occurs, like the discharge of lightning. The device was invented by Nikola Tesla, and its name carries its name.

By the type of switching element of the primary circuit, Tesla coils are divided into spark (SGTC - Spark Gap Tesla Coil), transistor (SSTC - Solid State Tesla Coil, DRSSTC - Dual Resonant Solid State Tesla Coil). I will consider only spark coils that are the most simple and common. By way of charge of the contour capacitor, spark coils are divided into 2 types: ACSGTC - Spark Gap Tesla Coil, as well as DCSGTC - Spark Gap Tesla Coil. In the first embodiment, the capacitor charge is carried out by alternating voltage, the resonance charge with a constant voltage is used in the second.

The coil itself is a design of two windings and a torus. The secondary winding is cylindrical, wounds on the dielectric pipe with a copper winding wire, into one layer of the turn to the turn, and it usually has 500-1500 turns. The optimal ratio of diameter and the winding length is 1: 3.5 - 1: 6. To increase electrical and mechanical strengthThe winding is covered with epoxy glue or polyurethane varnish. Usually, the dimensions of the secondary winding are determined based on the power of the power supply, that is, a high-voltage transformer. Having determined the diameter of the winding, from the optimal relationship is long. Next, select the diameter of the winding wire, so that the amount of turns is approximately equal to the generally accepted value. Sewer plastic pipes are usually used as a dielectric pipe, but a self-made pipe can be made using a drawing watman and epoxy sheets. Hereinafter, we are talking about medium coils, with a power of 1 kW and a secondary winding diameter from 10 cm.

On the upper end of the tube of the secondary winding, a hollow conductive torus is installed, usually made of aluminum corrugated pipe For removal of hot gases. Basically, the diameter of the pipe is selected with an equal diameter of the secondary winding. The torus diameter is usually 0.5-0.9 on the length of the secondary winding. The torus has an electrical container, which is determined by its geometric sizes, and acts as a condenser.

The primary winding is located at the lower base of the secondary winding, and has a spiral flat or conical shape. It usually consists of 5-20 turns of thick copper or aluminum wire. High-frequency currents occur in the winding, as a result of which the skin effect may have a significant impact. because of high frequency The current is distributed mainly in the surface layer of the conductor, thereby decreases the effective cross-sectional area of \u200b\u200bthe conductor, which leads to an increase in the active resistance and a decrease in the amplitude of electromagnetic oscillations. therefore the best option For the manufacture of the primary winding will be hollow copper tube, or flat wide ribbon. Above the primary winding over the outer diameter, an open protective ring (Strike Ring) is sometimes installed from the same conductor, and ground. The ring is designed to prevent discharges in the primary winding. The gap is necessary to exclude current flow through the ring, otherwise the magnetic field created by the induction current will weaken the magnetic field of the primary and secondary winding. You can refuse the protective ring if you ground one end of the primary winding, while the discharge hit will not harm the coil components.

The communication coefficient between windings depends on their mutual location than they are closer, the greater the coefficient. For spark coils, the typical coefficient value is k \u003d 0.1-0.3. The voltage on the secondary winding depends on it, the greater the communication factor, the greater the voltage. But it is not recommended to increase the communication factor above the norm, as it will start slipping the discharges damaging the secondary winding.


The diagram presents the simplest version of the ACSGTC Tesla Type Coil.
The principle of operation of the Tesla coil is based on the phenomenon of the resonance of two inductively related oscillatory contours. The primary oscillatory circuit consists of a C1 condenser, the primary winding L1, and communted by the arrester, as a result of which a closed circuit is formed. The secondary oscillating circuit is formed by the secondary winding L2 and the C2 capacitor (torus having a container), the lower end of the winding is necessarily grounded. With the coincidence of the proper frequency of the primary oscillating circuit with the frequency of the secondary oscillating circuit, there is a sharp increase in the amplitude of the voltage and current in the secondary chain. At a fairly high voltage, an electric air breakdown occurs in the form of a discharge outgoing from the torus. It is important to understand what is a closed secondary contour. The second circuit current flows through the secondary winding L2 and CONDENSER C2 (TOR), then by air and earth (since the winding is grounded), a closed circuit can be described as follows: Land winding-torch-discharge-land. Thus, the exciting electrical discharges are part of the contour current. With a large resistance to grounding discharge, outgoing from the torus to beat directly on the secondary winding, which is not good, so you need to do high-quality grounding.

After the dimensions of the secondary winding and the torus are defined, you can calculate your own frequency of oscillations of the secondary circuit. Here it is necessary to take into account that the secondary winding except inductance has some capacity due to the considerable sizes, which must be taken into account when calculating, the winding capacity must be added with the tactual capacity. Next, it is necessary to estimate the parameters of the C1 rebound coil parameters, so that the proper frequency of the primary circuit is close to the frequency of the secondary circuit. The capacitance of the primary circuit capacitor is usually 25-100 NF, based on this, the number of turns of the primary winding is calculated, there should be 5-20 turns on average. When making a winding, it is necessary to increase the number of turns, compared with the calculated value, for the subsequent setting of the coil into the resonance. You can calculate all these parameters according to standard formulas from the textbook of physics, also in the network there are books on calculating the inductance of various coils. There are also special Calculators programs for calculating all the parameters of the future Tesla coil.

The setting is carried out by changing the inductance of the primary winding, that is, one end of the winding is connected to the diagram, and the other is not connected anywhere. The second contact is performed in the form of a clamp, which can be transferred from one turn to another, thereby using the entire winding, but only its part, the inductance is changed, and the intrinsic frequency of the primary circuit changes. The setting is performed during the preliminary launches of the coil, the resonance is judged by the length of the issued discharges. There is also a method of cold adjustment of the resonance using a RF generator and an oscilloscope or a voltmeter, and the coil is not necessary to start. It is necessary to note that the electrical discharge has a capacity, as a result of which the proper frequency of the secondary circuit may slightly decrease during the coil operation. Grounding can also have a slight effect on the frequency of the secondary circuit.

The arrester is a commuting element in the primary oscillatory circuit. With an electrical sample of the arrester under the action of high voltage, an arc is formed in it, which closes the chain of the primary circuit, and high-frequency decaying oscillations arise, during which the voltage on the C1 condenser gradually decreases. After the arc goes out, the C1's contour capacitor again begins to charge from the power supply, the next time the discharge breaks starts a new oscillation cycle.

The arrester is divided into two types: static and rotating. The static arrester is two closely located electrodes, the distance between which is regulated so that the electrical breakdown between them occur at the time when the C1 condenser is charged to the greatest voltage, or a little less than the maximum. The estimated distance between the electrodes is determined based on the electrical strength of the air, which is about 3 kV / mm under standard conditions. ambientand also depends on the shape of the electrodes. For AC power voltage, the frequency of the static arrester (BPS - Beats Per Second) will be 100Hz.

The rotating arrester (RSG - Rotary Spark Gap) is performed on the basis of the electric motor, on the shaft of which the disk with the electrodes was imposed on each side of the disk, therefore, all the electrodes of the disk will fly between static electrodes. The distance between the electrodes makes minimal. In this embodiment, you can adjust the frequency of commutations over a wide range by controlling the electric motor, which gives more possibilities for setting up and controlling the coil. The engine housing must be grounded, to protect the engine winding from breakdown, when the high-voltage discharge is hit.

Condensation assemblies (MMC - Multi Mini Capacitor) from sequentially and parallel connected high-voltage high-frequency capacitors are used as a contour capacitor C1. Usually used Ceramic capacitors of the type KVI-3, as well as film K78-2. Recently, the transition to paper capacitors type K75-25 has been scheduled, which showed themselves well in operation. The rated voltage of the condenser assembly for reliability should be 1.5-2 times the amplitude voltage of the power supply. To protect capacitors from overvoltage (high-frequency pulses), the air arrester is installed in parallel to the entire assembly. The arrester may be two small electrodes.

A high-voltage transformer T1 is used as a power source for charging capacitors, or several sequentially or parallel to the connected transformers. Basically, beginner teslastroels use a transformer from microwave oven (Mot - Microwave Oven Transformer), the output variable voltage of which is ~ 2.2 kV, power is about 800 W. Depending on the rated voltage of the contour capacitor, the moths are connected sequentially from 2 to 4 pieces. Application of only one transformer is not advisable, since due to a small output voltage, the gap in the arrester will be very small, the result will be unstable results of the coil. Moth have disadvantages in the form of weak electrocrust, are not designed to work in a long time, they are very hot at high load, so often fail. More intelligently use special oil transformers like OM, OMP, OMG, which have an output voltage of 6.3 kV, 10 kV, and a capacity of 4 kW, 10 kW. You can also make a homemade high-voltage transformer. When working with high-voltage transformers, you should not forget about safety techniques, high voltage is dangerous for life, the transformer body must be grounded. If necessary, the autotransformer can be installed successively with the primary winding of the transformer, to adjust the voltage charging of the contour capacitor. The power of the autotransformer should not be less power transformer T1.

LD choke in the power circuit is required to limit the short-circuit current of the transformer when the discharge breakdown. Most often, the choke is in the chain of the secondary winding of the T1 transformer. Due to high voltage, the necessary inductance of the choke can take large values from units to dozen Henry. In this option, it must have sufficient electrocrust. With the same success, the choke can be installed in series with the primary winding of the transformer, respectively, it does not require high electrocrust, the necessary inductance is an order of magnitude lower, and is tens, hundreds of milligers. The diameter of the winding wire should be at least the diameter of the transformer primary wire winding. The inductance of the choke is calculated from the formula for the dependence of inductive resistance from the frequency of the AC.

The low frequency filter (FNH) is designed to eliminate the penetration of high-frequency pulses of the primary circuit into the throttle chain and the secondary winding of the transformer, that is, to protect them. The filter can be M-shaped or P-shaped. The filter cutoff frequency is chosen an order of magnitude less than the resonant frequency of the oscillatory contours of the coil, but the frequency of the cut should be much greater than the frequency of the arrester.


With the resonant charge of the contour capacitor (the type of coil - DCSGTC), use constant voltage, unlike ACSGTC. The secondary winding voltage of the T1 transformer is straightened with a diode bridge and smoothed the capacitor capacitor of the capacitor should be an order of magnitude larger than the C1 contour capacitor, to reduce constant voltage ripples. The magnitude of the tank is usually 1-5 microfi, the rated voltage for reliability is chosen by 1.5-2 times more amplitude straightened voltage. Instead of one capacitor, you can use condenser assemblies, it is desirable not forgetting about leveling resistors with a sequential connection of several capacitors.

A sequentially connected high-voltage diode poles of type KC201 and others are used as a bridge diodes. The rated current of the diode poles must be greater than the rated current of the secondary winding of the transformer. The reverse voltage of diode pillars depends on the straightening scheme, for reliability considerations, the reverse voltage of the diodes should be 2 times the amplitude voltage value. It is possible to manufacture homemade diode pillars by serial connection conventional rectifier diodes (for example, 1N5408, UEB \u003d 1000 V, IOM \u003d 3 A), using leveling resistors.
Instead standard scheme Straightening and smoothing can be collected voltage doubleder from two diode pillars and two capacitors.

The principle of operation of the resonant charge scheme is based on the self-induction of the LD choke, as well as the use of the cut-off diode VDO. At the time when the C1 capacitor is discharged, the current begins to flow through the throttle, and an increase in the sinusoidal law, and the energy is accumulated in the throttle magnetic fieldAnd the condenser is charged, accumulating the energy in the form of an electric field. The voltage on the condenser increases to the voltage of the power supply, while the maximum current flows through the throttle, and the voltage drop on it is zero. At the same time, the current cannot stop instantly, and continues to flow in the same direction due to the presence of self-induction of the choke. Charging the capacitor continues until the doubted power supply voltage value. The cut-off diode is necessary to prevent the power flow from the capacitor back to the power source, since the potential difference is equal to the power supply voltage between the condenser and the power supply. In fact, the voltage on the condenser does not reach the doubled value due to the presence of the voltage drop on the diode pole.

The use of a resonant charge allows you to more effectively and evenly transmit energy to the primary circuit, and to obtain the same result (by the length of the discharge), the DCSGTC requires a smaller power supply (transformer T1) than for ACSGTC. The discharges acquire a characteristic smooth bend, due to the stable supply voltage, unlike the ACSGTC, where the next rapprochement of the electrodes in RSG may have time to any section of the sinusoidal voltage, including a zero or low voltage hit and as a result of the discharge length (ripped discharge).

Below in the picture presents formulas for calculating the parameters of the Tesla coil:

I suggest familiarizing yourself with my experience of building.

In the case of solid bodies, interconnected, the forces acting on this system can be divided into two groups:

1) external forces;

2) Domestic forces.

Internal forces are called the forces of interaction between bodies belonging to this system. According to the Law of Equality and Counteraction, the internal forces are always pairwise equal in the module and are directly opposite to the direction, but applied to two different interacting bodies of the system.

The external forces are called those forces with which the bodies that are not included in this system act on the bodies of this system.

Consider, for example, the system shown in Fig. 39. The beam AB weight can rotate around the axis A of a fixed cylindrical hinge and the end in reluctantly on another CD beam weighing, which is subhead at the point E and connected to the wall of the hinge.

In this case, the system consists of two bodies: AB and beam beams.

The internal forces for the DHNEY system are the forces of interaction between beams, i.e., the power of the AV beam pressure on the CD beam and the force with which the CD beam acts on the AV beam. According to the law of equality and countering force N, and are equal in the module and are opposite to the direction, i.e..

Weight and beams are the forces with which these beams are attracted to the Earth, and, therefore, for this system are the forces external, as the Earth relative to this system is an external body. Reactions and hinge supports A and D, as well as the reaction of support E are for this system, too, by external forces, since the hinged supports A and D and the support E do not belong to the system under consideration consisting only of two beams.

When solving problems for equilibrium bodies, it is necessary to consider that all external and internal forces applied to each body separately are balanced. Therefore, in the case of a flat system of power, three equilibrium equations can be made for each of these bodies separately.

Thus, for a system consisting of bodies, the equations of equilibrium can be made. Therefore, if the number of unknown forces in this task is no more, then such a task is statically defined. If the number of unknown in the problem is greater, this task cannot be permitted only on the basis of the equal solid body equations and therefore it is statically uncertain.

Since the internal forces are pairwise equal in size and directed along one straight line to the opposite directions, the algebraic sum of their moments relative to any point is zero and the sum of their projections on any axis is also zero. Therefore, if the equilibrium equation (the equation of moments relative to any point, or the equation of projections on any axis) for each body is separate and then all the equations will add, then in the resulting equation, members containing internal forces are destroyed in pairs and, therefore, This equation will include only external forces.

Thus, if the boding system is in equilibrium, then the external forces applied to this system satisfy the same three equilibrium equations as in the case of equilibrium of one absolutely solid body. These equations are the equilibrium conditions of the external forces acting on the system.

From these equation, you can find all external reactions if the number of these external reactions is not more than three.

If the number of external reactions will be more than three or if in the problem, in addition to external reactions, it is required to find unknown internal forces, it is necessary to apply the method of dismembering the system, that is, it is necessary to consider the equilibrium of each body of the system separately and for each of these bodies to make equations Equilibrium, taking into account all the forces attached to the body under consideration. If the system consists, for example, of two solid bodies, then, applying the dismemberment method, we get in the general case six equilibrium equations (three equations for each body). To compile six equilibrium equations, you can also apply another reception, namely: to form three equations for the entire system as a whole (as for one absolutely solid body) and then to these three equations to attach three equilibrium equations, compiled only for one of two bodies This system. This second reception is often preferable, since the equilibrium equation, compiled for the entire system as a whole, includes only external forces and therefore these equations are usually simpler.

The tasks relating to the equilibrium system of solid bodies, depending on the type of connection of these bodies, can be divided into the next four types:

1. Tasks where the bodies entering the system are based on each other.

2. Tasks where the bodies that are included in the system are interconnected by flexible thread or weightless rod, the ends of which are attached to these bodies with hinges.

3. Tasks where the bodies entering the system are interconnected using a hinge.

4. Tasks related to the definition of efforts in the rods of a flat farm.

Today, houses are so diverse today that the erected structures sometimes acquire a completely quaint look. Especially architects love to experiment with the roof, which is made and flat for picnics, and transparent for winter Gardenand in the form of a bizarre flower.

However, most practical remains the most simple options, such as a double roof. Consider the device of the chalk system double roof in this article.

With this design, a large attic space is created that does not require special insulation, so it is very popular when building residential buildings.

In addition, it is easy to install in contrast, for example, from four-page and does not require large investments during installation.

The double roof is a design of two rectangular surfaces, the upper parts of the connected to each other, and the bottom resting on the walls of the house.

Thus, the roof remains unclothed two triangular parts in the ends - frontoths. These parts are either performed by deaf, or used for the input device in the attic.

Very convenient to use the resulting attic room For an extra room, which can be used in the warm time. And if you make an effort and insulate it, then you will get a full room suitable for life and winter.

The main parts of the rafting roof are visible in the figure:

• mauerlat, holding the whole design on the walls;
• rafters forming the roof itself;
• the doomle on which the roof coating is attached;
• the ski run connecting two planes of the roof at the top;
• racks and saws, additionally reinforcing roof.

The construction of the rafter can be two types:

• hanging;
• inclined.

Hanging rafters are fixed only at two points - on the skate and on the walls. Therefore, their design is subjected to two types of load - compression and bending. In addition, inclined in addition to this, in the middle part, rely on intermediate supports, which significantly reduces bending loads.

Most effective way The devices of the solid system of the two-tie roof is a combination of hanging and inclined rafters. Such a combination increases the strength of the structure and reduces the consumption of materials.

Thanks to such simplicity of design, the double roof has a number of advantages:

• simplicity of performance and repair when damaged;
• a small cost of work and materials;
• high wear resistance and strength;
• the low probability of leaks, since such a roof has no joints different surfaces, the design is almost whole;
• the ability to device a full-fledged residential area in the attic.

Payment

Before mounting a rafter system, it is necessary to carry out its calculation. This requires perfection and attentiveness, all calculations need to be tweaked a couple of times. Stay in the midst of work without the right building materials or, on the contrary, buying too much will cost you much more expensive.

In case the installation of a two-sheet roof is made by a detailed project, it is necessary to select all the elements of its design with the dimensions and the number of each position. Using the principles of rational cutting, fold the volumes by:

• species of sawn timber (M.P.);
• vaporizolation material (m 2);
• roofing (amount per pc, m 2);
• insulation (m 2).

For the convenience of calculations, it is best to calculate the area of \u200b\u200beach simple element separately, and then folded the results.

For clarity of the calculations, we calculate several options for the roof for houses of the same length of 8 m and width 4, 5, 6, 7 and 8 m. We will define that the angle at the top of the roof (from the skate c) they will have the same - 120 °. The corners of the roof row at the mounting points to Mauerlat (A and B) also in this case will be the same - 30 °.

We begin with the calculation of the height of the roof H, it is calculated by the formula

Length of rafted speakers according to theorem rectangular triangle, calculated as half of the width of the house of AB, divided into sinus ½ angle α at the top

AC \u003d ½AV / SIN (α / 2) + 0.5 m

The value obtained is required to add the length of the cornese swell, which ranges from 0.5 to 0.8 m.

The total amount of material that we need for the manufacture of rafters, calculate how the product of the length of one rafter to the desired number of rafters.

The step of the rafter is chosen from the standard range of 0.6-1 m.

We define for our calculation that the step of the rafter will be 0.7 m.

In the area where there is elevated level Accumation of snow, it is necessary to strengthen the truck system - to establish a solid crate and paired rafters.

So, from the results obtained to make a table, studying which, you can understand how the width of the building affects the number of materials necessary for the device of the solid system of the two-tie roof.

Please note that the exact formulas calculates the exact value of the materials. On sale board, tile, slate and all other materials are only certain sizes. You are unlikely to purchase a 5.12 m long chalkboard. It is possible that the closest size will be 7 or even 8 m, and you will be unnecessary.

When calculating and buying a material, it is necessary to take into account that on sale it only has fixed sizes, which do not coincide with yours, and part it will go into waste.

Of course, the final calculation of the number of required materials is better to entrust the specialists, but using the proposed scheme, you can pre-determine what expenses you expect.

Installation

You can set the truck system in two ways:

• mount rafters directly at the installation site;
• mount the rafter pairs (farm) on earth and raise up.

The first method requires smaller physical effort, and the second allows the use of a wide construction site and reduces the risk of falling from height.

"Farm" is called a pair of rafter feet interconnected in accordance with the project.

Required tool

From how you prepare for work, directly depends on how quickly and efficiently spend them and how convenient will you work.

For work on the device of the rafter system, it is necessary:

• ax;
• hammers different weight and species;
• nail holder;
• screwdriver;
• hacksaw or chainsaw;
• bulgarian;
• drill with a set of drills and zenker;
• long roulette;
• construction level and plumb;
• pencil, marker for applying;
• construction cord;
• fastening fittings: corners, planks, nails and self-tapping screws.

Making template

To facilitate the connection of the rafters in the farm and compliance with the same sizes, the template should be made on which the rafters will be cut off and connect. For this, two long boards use, connecting them in the form of a letter A in exact accordance with the dimensions of the future roof. Then each rafter pair is adjusted to this pattern and secure, gradually forming a roofing system.

The rigidity of the built-in design directly depends on how high quality and firmly fixed with each other. Special metal lining should be used to increase the strength at the places of compounds.

Fastening rafted to Mauerlat

The most important element when installing the roof - fastening rafters to Mauerlat.

It can be carried out in two ways:

• rigid;
• sliding.

Hard fastening of rafters to Mauerlat eliminates any impacts on the resulting connection - shifts, turns, bends. Such durability can be achieved, stringly rafters with supports, bars, metal corners, use brackets and nails. Additionally, you can fix rafters to the wall with anchors or wire.

The moving fastening of rafters to Mauerlat has two degrees of freedom. This mount is recommended for roofs. wooden houses. The rafters are able to move along its longitudinal axis. To do this, they are placed in special cuts of Mauerlat, excluding lateral movements, but allowing you to move up and down. Such limiters can also be made from two limiting large nails or a special plate.

Ferm Installation

Farms are installed along the ends of the building, and the cord is tight between them. The cord must be strictly horizontally, which is controlled by the level. If one of his ends turns out to be higher than the other, then the farm, to which he is tied, will be necessary to lower a little.

To exclude the sagging of the rafter system from the load, it is required to increase the medium rafters with special pins.

The remaining rafters are installed in terms of this cord with the necessary step and are fixed with the disconsets, retaining beams and other methods provided by the project.

Aluminum stairs are a design of two racks interconnected by steps. Aluminum and silicon alloy is usually used as the manufacturer's material. This ensures the high strength of such products. Such stairs usually have different types Designs. It depends on the purpose of their use.

Four-section Staircase - Tool for a wide variety of works

Types of aluminum stairs

Aluminum stairs According to the design of the structure differ on the same, two-, three- and four-section. They have from 6 to 25 steps and apply for various purposes. While doing household work A stepladder is useful, able to cope with most tasks. The most common stairs, having the main part of the metal, and the legs with steps are made of plastic.

In addition to domestic, these types of structures can be distinguished:

Household ladders, as well as dielectrics and most transformers have many additional details. They increase the safety and reliability of structures.

Types of stairs

Most modern stairs It turns out to be indispensable for operation at height, both in domestic conditions and in manufacturing enterprises. According to this sign, they are divided into used in everyday life and professional.
The first type of products is performed from aluminum, has a high ease, simplicity of the design and must respond important requirements - Strength, simplicity of carrying and installation, security, inconspicuous to storage conditions.

Professional designs have near characteristic featuresdefining the scope of their application. For example, transformers are characterized by high functionality and are often exploited as a variety. Telescopic stairs are very compact and allow you to perform the same amount of work as many three-section structures.

Design features

The maximum weight of the user of aluminum stairs varies - from 100 to 150 kg. With more high indicators It can be said that the design is professional. The working length is measured to the last platform or the steps. Professional designs have a height of 15-20 meters.

Note: Sometimes the working length can be considered height from the floor to the penultimate stage, and 120 cm is added to it. This question is better to clarify the seller.

Single-section stairs

The staircase of three sections is like a stepladder, only better

This design is called the Power, and it requires a vertical support. To avoid ridiculous injuries when used, the legs need to be well fixed. The distinctive features of the filter structures are:

1. Widespread use in everyday life. Indispensable with easy repair, work in the garden, in the country. It allows, without much effort to collect a crop and chop dried branches of trees.
2. A single-sectional ladder is not extended when carrying out installation and construction work. Frequent use is due to ease of use - it is only worth noticeing to the wall and securely secure.
3. Choice. When buying an internal single-section staircase, the main parameter to which you want to pay attention is height. Not only the functionality of the product depends on it, but the cost. On the construction market Available various options: from 1.5 to 5.6 meters long.

Production material (aluminum with dural, magnesium, silicon) is characterized by high strength and long time Services. Although the stairs for drawing aluminum single-section are still inferior to their advanced versions.

Two-section structures

The peculiarities of such stairs include: anti-slip steps, a variety of models (from 3 to 25 steps) and the possibility of bilateral climb. The maximum stirring height comes to 13 meters. The advantages of the stairs include corrosion resistance, unlimited operating conditions, low weight and compactness.

Two-section aluminum stairs have 2 types of design: folding (stepladers) and sliding. The latter differ in that one part of them is extended from another. The recommended load does not exceed 150 kg. Similar structures are distinguished by high functionality and convenience, can be used as dotted.

Any staircase, the same two-section aluminum, must first have the necessary functionality.

Three-section stairs

With the help of such a staircase, you can easily paint the ceilings and inaccessible from the floor

It is possible to use such a staircase in the form of a ladder, anxious design. It has transverse stretching between the legs, which ensures the greatest strength. Aluminum profile allows you to use a design with a load of up to 150 kg.
Is a product for domestic use. In the form of an inlet staircase, it usually reaches a height of 6 meters. As a stepladder can be used at an altitude of 5 meters.
In folded form, such a staircase most often has the following dimensions (height, width, depth): 2.5 * 0.4 * 0.15. The approximate width of the stage is 25 mm. Caps are performed from two-component plastic.

Floor section products

Stairs with 4 sections are called by transformers. They are most functional and used both as a stepladder and in the form of dotted structures. Can replace the scaffold.

main feature Such stairs are relatively rare use. They have several parts connected by hinged mechanisms. The advantage is compactness in folded form, as well as high stability and reliability in use.

Distinctive features Such structures consist in high functionality, a large working length, the ability to withstand a large load - up to 150 kg, the possibility of using the principle of the inlet ladder, the maximum simplification of complex construction work.

A small mass of the product allows you to easily carry it in the process of work. It is also convenient to be able to quickly change the height. working surface.

Advantages of the 4-section Step

Due to its design, the four-section staircase can cope with a huge amount of tasks and has several advantages:

• compactness;
• high stability on different types of surfaces;
• the presence of a special relief;
• high strength of the product provided by an aluminum profile;
• convenient in storage and during transportation;

Composite elements of the stairs due to the characteristics allow the staircase to withstand significant operational loads. Suitable for both lovers and professional-level builders.

The cost of aluminum stairs

Now let's turn to the most interesting question: how much do such designs cost? Aluminum stairs depending on the characteristics have a large variation of the cost. Below are the main types of their.

So, prices for structures with only 2 sections:

• two-section staircase (maximum length 314 cm, weight - 6.4 kg) aluminum - 5 thousand rubles;
• the same design that has a length of 427 cm costs about 6.3 thousand rubles;
• universal two-section staircase with a 687 cm working height will cost the buyer at 11 thousand rubles;
• sliding structures can cost from 4.5 to 12 thousand rubles;
• universal stairs can be purchased for 5.5-12.5 thousand rubles.
• three-section staircases cost from 3.5 to 11 thousand rubles, and the prices for structures consisting of their 4 parts range from 5.5 to 12 thousand rubles.

As can be seen at the rates, four-section products differ not only to high operational characteristics, but also accessibility.

How to choose the desired staircase

Before buying a specific product, you should decide on it. necessary characteristics and operating tasks.

Before buying, carefully examine the staircase on the build quality

For proper choice The staircase will certainly help achieve high goals. For example, as cosmetic repair Apartments are suitable for the usual attachment. First of all, consider the applications. stair structures:

• repair I. construction works;
• household needs;
• electric installation work;
• use in large libraries;
• work in the garden.

It is necessary to select the necessary working height, maximum load and pay attention to the presence of special fasteners.

Entrance metal double doors represent a design of two doors. Most often these are two doors, outdoor and internal, and the outdoor opens on staircase, and internal - in the apartment. In some cases, under the phrase "double entrance doors"Measures a double door, but it is rather an exception than the rule.

It is convenient to install double entrance doors when it allows the width of the doorway and there is no second single-door door to the apartment. There are projects of houses, where the double door is provided with the design, and the architecture of the building contributes to such a choice. Sometimes double doors are installed and in accordance with technological restrictions.

Double door: Increased safety of your home.

For the same reasons, double doors with framugs can be installed. Their advantage is that they can easily overlap the opening of large sizes.

Before you start choosing a double metal door, you should pay attention to the components of the structure. Framuga is a static element of metal doors, which does not open and manufactured from the same materials as the other parts of the double door. Framuga consists of an outer and inner cover. For greater strength, it has rigidity ribs. Also, the fraumuga must have excellent insulating properties: do not pass warm and sound.

Double entrances metal doors can be with a collapsible fraumuga, or represented by a one-piece element. Due to this, such doors can close the openings of different, including non-standard, sizes.

Framuga can be an all-welded with a box of the door - then the metal structures will be uniform. But it can also be removable and attached separately.

The most basic when selecting double entrance doors is the choice of the parameters of the fixed and rotary sash. Because A similar door design consists of two canvases, in addition to the main locking mechanism, the doors are equipped with a special lock, locking the fixed sash. Double doors are no less reliable than ordinary single-holder, because Their design implies a profile door frame. If you want to install the metal and wooden entrance doors at the same time, then you need to thoroughly check their size.

Most often double metal entrance doors are installed in apartment houses To create a tambour before adjacent apartments. A common occurrence in such cases - the installation of the usual is not armored iron Door Without additional protective elements. Therefore, the attacker will not be much difficult to discover such a door, and in the vestibule it is much more convenient to open the locks on the other entrance doors. Therefore, you should take care of security, and carefully approach the selection of a tambourine door.

Tambourous doors serve to control access to the room. In most cases, such doors are not inspected.

If bivalve entrance doors are installed as an external one, then a visor is required over them to reduce the effects on the doors of the sun's rays, the temperature drop and other effects.

Types of double doors

Double metal doors can be installed as independent designOr in a tandem with a wooden single door. The most common installation options:

In addition to this design, double entrance doors can consist of two sash. It's pretty convenient - if you need to put a large house household appliances, The second sash opens, significantly increasing the width of the opening.

Installation double door appropriate with the width of the opening more than 110 cm. They can be installed not only in residential buildings, but also to offices, public buildings or industrial premises - Everywhere, where non-standard doorway width will not allow the usual door. Double doors are often used as driveway.

Depending on the purpose and configuration, double entrance doors are characterized by such parameters:

• door finish (external and internal);
• type of castle systems;
• accessories;
• insulating characteristics.

Despite the fact that double metal entrance doors themselves already non-standard formthey can have unusual arched shape And finish. Often together S. decorative materials Used artistic forging, giving the doors an elegant and stylish look.

The entrance door decorated with artistic forging will always be unique.

Pros and Cons Metal Double Doors

Consider why dual metal doors are gaining popularity and are increasingly installed not only in office rooms, but also as entrance doors in the apartment.

1. Double metal doors provide a high security class. Even if one door is hacked, the second will delay the attackers before the arrival of law enforcement agencies.
2. Double doors provide much better thermal insulation than single. If the entrance doors come out in a tambour, but on the staircase, such a parameter is especially important.
3. Available cost. Input metal doors are not only more reliable, but also cheaper made by their tree. Almost everyone can afford steel doors.
4. If you put metal double doors, you do not have to spend money on their service. They will not require additional operating costs other than installation.
5. Metal entrance doors are durable and reliable. High-quality metal is not deformed under the influence of atmospheric precipitation, it moves well sun rays and physical impact.

These benefits when installing double metal doors are very significant, but there are disadvantages:

1. Metal in its structure does not support a healthy microclimate in the apartment.
2. Many consider metal doors too rude.
3. Compared to wooden, steel doors spend sound well.

Double metal doors will ensure inexhibence to your home.

Thus, the input metal doors are the optimal value for money, they are indispensable for the apartment and reliably protect you and your property.