Today, in cottage, multi-storey, commercial and residential construction, the system of passive and active ventilation, the air heating or air purification system are widely used.
Considering that earlier for such a purpose they left a void in the wall and ceiling, today the laying of ventilation communications is carried out by a line for the production of air ducts or a ventilation pipe (a special hollow pipe-like structure to accommodate the supply air and eliminate the polluted environment).
Classification
Air ducts are different and they are classified according to different criteria:
Plastic air ducts
- shape (rectangular and round duct);
- material (various plastic, galvanized and stainless steel, aluminum, polyester, fiberglass, thermoplastic or other specialized rubber, silicone);
- the presence of special characteristics (flexible air duct, fire retardant);
- connection method (using a nipple or special fasteners).
Two main types of ducts:
- Hard.
- Flexible (frame).
The most common option is a round or rectangular duct made of galvanized steel or aluminum. They are produced by a specialized automatic air duct production line. It is practical, cheaper than plastic, faster and easier to install, fire retardant and will not rust. It also has aerodynamic low drag. This type of air duct, as a rule, is used for ventilation systems of various enterprises, offices, large cultural and entertainment complex, sports, educational, institutions, catering organizations. Also for any other type of buildings that have a room with a large area, where the operation of the air duct requires dynamic air exchange.
Galvanized steel air ducts A more complex option is a flexible duct. It is used only under specific circumstances. For example, in a small room that has a complex structure or that does not have a large galvanized air duct suitable for installation. It is also used for active ventilation systems: extractor with a fan, removal of acid vapors and hot air from industrial buildings.
Of course, a flexible ventilation pipe is more expensive than a rigid pipe. However, it is necessary to start production with rigid air ducts, since they are more in demand and, therefore, easier to sell.
The manufacturing process of an air duct, both rectangular and round, is absolutely unremarkable and seems to be simple roll-forming operations that are performed on specialized automatic equipment.
It is very important to correctly select the air duct production line itself and create a rhythmic process of manufacturing and marketing (realization) of the final product.
Production technology
The process of production of air ducts is very simple. Production is carried out by an operation that requires specialized metalworking equipment. Given the type of construction, the production technology itself also comes into play.
Connecting fittings for air ducts The quality of the finished product depends on the quality of the metal and machine tools. Particular attention is paid to the production of fastening and connecting fittings: couplings (nipples), plugs, tie-ins, bends. Galvanized steel air ducts remain the most popular air duct used in today's ventilation and air conditioning systems.
The manufacture of a galvanized duct seems to be a fairly simple process, however, it has a number of fundamental nuances. The seam gives strength to the structure. The tightness of the seams and, therefore, the air ducts as a whole is of the utmost importance.
The most conscientious manufacturers produce air ducts made on high-quality European technology. European quality standards are quite high and demanding, so that a responsible manufacturer in the end always makes a choice in their favor.
The production of galvanized air ducts is a process that requires exact observance of the required characteristics and dimensions. From a large sheet of galvanized steel, you can make an air duct of various shapes and sizes, both template forms and custom-made. The most common are round ducts. It can also be a straight-line duct. A large sheet of galvanized steel is rolled into a circle and tightly linked with a seam.
Galvanized steel - raw material for air ducts Such an air duct can have a large diameter, create little resistance in the air flow. In addition, a round air duct can be spiral-lock or spiral-wound. The special technique that is used to produce a round duct can make it very durable and functional. Air duct manufacturing technology is based on twisting galvanized steel strips into a spiral shape. With the help of a specialized profiled edge, the rectangular duct production line has a coil that is securely fastened with a so-called lock.
This technique will expand the continuous section of pipes and make the structure more durable. Moreover, this increases the characteristics of the overall sound insulation of the duct. The small number of the connecting element makes the construction more reliable. The pipe section is connected using a nipple connection.
The manufactured air duct can have a profile of rectangular sections. Such an air duct, taking into account its high compactness and a large number of size variations, is hidden behind a decorative wall or ceiling, while maintaining desired speed air flow.
The cost of a line for the production of rectangular ducts is slightly higher than for a round straight-seam duct. You can make a hidden gasket, which will make it indispensable, because it is necessary on most objects. The high strength, reliability and durability of the galvanized ventilation pipe has made it the most popular in the current construction market.
Rectangular ventilation duct is connected with flange or without flange connection. They are made from a large, solid sheet of galvanized steel and are always a little over a meter long. The accuracy of the parameters of rectangular ducts directly depends on the quality of the equipment that is used.
Equipment for the production of spiral ducts
Equipment
When choosing an air duct production line, there are three main characteristics of the ventilation pipe to consider:
If everything is very clear with rigidity: a flexible duct is less in demand, but a little more expensive than a rigid one. However, rigid pipes are purchased more, although they are cheap. With the shape and cross-sectional area a little more complicated. From these characteristics depends, for example, the speed of air flow and, therefore, the level of sound insulation.
In addition, there are other options to choose from. For example, a round duct is easier and faster to install, does not have a protruding part, has a greater strength and creates little aerodynamic drag (this is due to its natural shape).
A round vent pipe is easier to produce, since it is fastened with a snap nipple.
However, a rectangular duct has a better air flow rate in a ventilated area if a large cross-sectional area is needed or if the installation is in difficult circumstances, such as above a suspended ceiling.
Analyzing the market, we can conclude that the round and rectangular rigid ventilation pipe is sold in approximately equal shares. Taking into account the fact that they are produced using the same raw materials (galvanized steel or aluminum with a thickness of 0.6 to 1.1 mm), then for successful business you need to buy both lines (for the production of round and rectangular ducts).
The standard line for the production of air ducts of any section includes:
- unwinding machine for rolled metal sheets;
- feeding machine;
- machine for adjusting the sheet (the error of the duct diagonal allowed by the technique is 0.9 mm: ventilation pipes with detuned geometry produce powerful noise from the air flow, therefore all modern lines are equipped with such a function);
- guillotine, which cuts off finished air ducts;
- industrial CNC system.
The price of the circular duct production line, which are produced Russian manufacturer, is 1,376,285 rubles, or a little over 48 thousand dollars. The price of the line for the production of a rectangular air duct also from a domestic manufacturer is 1,688,952 rubles, or 57 thousand dollars.
Differences in the lines for the production of rectangular air ducts and round air ducts are manifested in the fact that in round air ducts the forming unit is a rolling roller. And in a rectangular air duct - a system for applying a stiffener, a corner cutting device and an automatic bending machine with a turning beam.
The total cost is quite small and amounts to approximately 3 million rubles. The profitability, which is 50% of the total costs, is very modest for such production. The selling price is from 125 to 3050 rubles per linear meter (depending on the diameter) when working in one shift and a five-day working week, the net income per month is at least 750-850 thousand rubles. Payback is approximately six months.
Automatic lines
Modern system ventilation is hard to imagine without components such as air ducts. This product has the most diverse version. The main task of any air ducts is to facilitate the rapid transport of oxygen, while minimizing the noise level.
The production of a high-quality rectangular duct requires the availability of appropriate technology. This equipment is an automatic line for the production of rectangular air ducts. With the help of this technique, which is equipped with a CNC system, you can easily perform the following operations:
- bending simple corners;
- creation of ducts in rectangular ducts;
- sheet cutting (in relation to the given parameters).
The use of this line will significantly increase the speed of manufacturing a rectangular duct and significantly reduce the proportion of defective products (in most cases, the defect is associated with the human factor).
Only one worker is needed to manage the production process. The dimensions of the product that should be the result and the amount of the product are set using the Touch-Screen controller.
This technique is equipped with a modular design, which makes it possible to use it when different combinations. The modular design performs the following functions:
- supply of metals;
- straightening of metals;
- applying a stiffener;
- transverse cutting of metal;
- bending.
To speed up manufacturing process multiple decoilers are required. This will significantly minimize the time consumption, because there will be no need for readjustment when changing from one thickness to another metal thickness.
Profitability
At first glance, the most obvious prospect in automatic lines the production of air ducts seems to be the organization of a service for the design and installation of a ventilation system. But this is the last step in the development of this business.
Initially, it is necessary to make mounting and connecting fittings for the air duct: bends, nipples (couplings), plugs, tie-ins, umbrellas, galvanized mounting perforated tape. This material is often made from scrap, substandard goods or other waste products.
The second step is the progressive expansion of the choice of product range, which is produced:
- rigid plastic pipes;
- flexible PVC pipes;
- polyester pipes;
- rubber pipes;
- silicone pipes;
- other ventilation pipes that do not require big investment into technology.
This will help the entrepreneur to occupy the minimum regional market segment.
And only after thoroughly preparing the industrial base and showing stable work for a couple of months, you can hire a ventilation system engineer. The installers themselves, as well as the workshop employees, may not have a special specialized education, therefore, their services are valued a little less than other workers. But an engineer specializing in heat and gas supply and ventilation is an employee with full higher education. They offer a service for the sale of ventilation, air purification or heating systems. Their work is highly valued accordingly.
Video: Production of air ducts for ventilation systems
In modern construction - even multi-storey, even cottage, even commercial, even residential - systems of passive and active ventilation, air heating and air purification are widely used.
If earlier voids were specially left in ceilings and walls for these purposes, today ventilation communications are laid using ventilation ducts (they are also called air ducts, ventilation pipes). These are special tubular hollow structures that allow you to distribute supply air and remove polluted air.
Types of air ducts
The production of ventilation ducts can become quite profitable business, but first you need to decide what specific types of structures you want to produce. Air ducts can be classified according to different criteria. So, depending on the shape, round and rectangular ventilation ducts are distinguished, based on the material used, the structures can be plastic, steel (galvanized or stainless steel), aluminum, polyester, thermoplastic, silicone, fiberglass and so on.
Availability special properties air ducts are divided into fire retardant, stainless and others, according to the connection method - into those that have special fasteners and those that are connected using nipples. There are two main types of ventilation ducts: flexible (they are also called frame) and rigid.
Choosing which ducts to produce
Manufacturing ventilation pipes rectangular or round shape made of aluminum or steel is the easiest option. Such structures are faster and easier to install than plastic ones, and also have a lower cost, they do not rust, are fire retardant, and have low aerodynamic resistance.
Installation of ventilation with such air ducts can be carried out at enterprises, offices, sports, educational, cultural and entertainment institutions, organizations Catering and in general in any buildings where there are large premises, during the operation of which active air exchange is expected.
Making flexible ventilation ducts is a more complex process. They can only be used in specific conditions, for example, in rooms with a complex configuration or in buildings where ventilation installation using large galvanized ventilation pipes is not possible. Also, such structures are used in rooms where it is impossible to provide active ventilation systems, for example, hoods to remove hot air and acid vapors.
The cost of manufacturing ventilation pipes from rigid materials will be less, but it is necessary to start production with them not for this reason, but because you can quickly implement such air ducts.
Production process
Structures of any kind are made on special automatic machines. In fact, the production process is a conventional roll forming operations. We will not talk in detail about how to make a ventilation duct. After all, this is not done manually, but with the help of technical devices. Therefore, the most important task for you, if you want to create a successfully functioning enterprise, is to choose good equipment for the production of ventilation.
We take into account important parameters
When choosing fixed assets, be guided by the main parameters of air ducts: stiffness, area and cross-sectional shape (based on the degree of demand in the market). We have already talked about rigidity, so everything is clear with this. Flexible ventilation ducts can be sold more expensive than rigid ones, but they are also less in demand.
As for the area and shape of the section, here the matter with the choice is more complicated. Different indicators will depend on what specific designs you will use, for example, the speed of the air flow, and, consequently, the level of noise emitted by this flow in case the speed standards are exceeded.
Other selection factors
The production of round ventilation ducts is less laborious, since they are fastened with clip-on nipples. Also, such air ducts are faster and easier to install, because they do not have protruding parts. They are durable and, due to their more natural shape, create less aerodynamic drag.
At the same time, rectangular ventilation pipes show the best indoor airflow when a large cross-sectional area is required or when installation is carried out in difficult conditions, for example, above suspended ceilings.
The manufacture of round and rectangular ventilation ducts is carried out from the same materials: either aluminum with a thickness of half a millimeter to a millimeter, or galvanized steel. According to statistics, their sales volume is also almost equal, they are in the same demand.
And yet, if you want to make your business more successful, purchase ventilation production equipment, which includes lines for the production of both round and rectangular pipes. What kind of cars do you need?
We equip the workshop for the production of air ducts
So, the production line for the manufacture of ventilation ducts of any section should include:
- feeding device;
- automatic machine for unwinding metal rolled sheet;
- apparatus for straightening a sheet (the technology allows a diagonal deviation of both the blank sheet and the air duct itself by 0.8 mm - if the ventilation pipe has a strong geometry violation, then a lot of noise will be emitted from the air flow, so modern technology in without fail includes dressing device);
- industrial numerical control system;
- guillotine that cuts off the finished duct.
The line used for the production of rectangular and round ventilation pipes differs only in that in the first case, the shaping units are corner cutting devices, a rib stiffening system, an automatic sheet bender equipped with a rotary beam, and in the second case, rolling rollers.
Process line cost
The production of ventilation ducts is quite expensive. A line for the manufacture of circular ducts (provided that the manufacturer is domestic) will cost about one and a half million rubles.
The cost of the line for the production of rectangular ventilation pipes will be from 1.8 million rubles and more. That is, in order to purchase both lines, you need to have in stock no less, but 3.3 million rubles by the most minimal standards.
Payback period
But there is also good news. Profitability in this area of business is quite high. And if you sell a linear meter at a price of 120-3000 rubles (depending on the diameter of the pipes), then even if you work in one shift five days a week, you can recoup the costs in six months.
Development prospects
The production of ventilation ducts is a promising business. Having established the technological process, you can expand your business and also engage in the manufacture of connecting and fastening fittings for pipes: plugs, nipples, "umbrellas", tie-ins, mounting punched tape and other things. Such products can be made from substandard goods, scraps and other waste.
In addition, try to enrich the product range: start making rigid plastic, polyester, silicone, flexible PVC, rubber and other air ducts. This will allow you to at least occupy a regional market segment in the field of ventilation systems.
Having worked steadily for at least six months and having thoroughly prepared the technological base, you can engage, among other things, in organizing services for the design and installation of ventilation systems. To do this, you will need to hire engineers who specialize in heat and gas supply work.
These are sought-after specialists at the present time, so get ready that their work will not be cheap at all. Also among the employees you will need installers, but their work is not valued so highly, it is believed that these are low-skilled workers, and sometimes they may not be qualified at all. Having recruited staff, you can offer services for the installation of ventilation systems.
Duct production
Box for ventilation and air conditioning systems are used in the construction of any duct systems. The material for their manufacture is selected depending on the actual operating conditions, the parameters of the working environment, and also on the purpose. For the manufacture of air ducts use low-carbon steel, "galvanized" or "stainless steel", as well as different kinds plastic.
Air ducts for ventilation made of "galvanized" are used in air exchange systems with a working environment with a temperature of up to + 80C (a short increase up to + 200C is possible) and humidity up to 60%. Air ducts made of galvanized steel can be used in areas with any climate in accordance with GOST 15150, subject to non-aggressive working environments (air and gas-air). Galvanized air ducts do without an additional protective coating, since the top zinc layer protects the metal from corrosion even in places where it is damaged (due to the steel-zinc galvanic pair, which forms an oxide film under the influence of atmospheric oxygen).
Air ducts made of stainless steel are designed to work with superheated air and aggressive gas-air mixtures. Working environment temperature - up to +500С (short-term increase up to +700С is allowed). As a procurement material for the production of stainless steel air ducts, steels are used according to GOST 5632-72 (heat and corrosion resistant).
"Black" air ducts are made from mild steel. Workpiece thickness - from 1.2 to 15 mm. "Black" air ducts for ventilation tolerate high temperatures and exposure to open flames well (they are slightly susceptible to deformation - the air ducts of the ventilation system do not depressurize and the fire does not spread to neighboring rooms).
For aspiration systems and smoke removal, "black" ventilation ducts are the most right choice. Simple carbon steel ventilation systems are mainly in demand in production areas where excessive emission of gases, dust, etc. is possible.
Air ducts can be round or rectangular in cross section. The production of rectangular ducts is a classic of ventilation systems, but thanks to progressive technologies, the market is increasingly losing ground to round ducts, since they are more technologically advanced in manufacturing, have better aerodynamic characteristics and are easy to install. To date, the production of round air ducts is "gaining momentum", becoming more and more popular.
For the installation of air ducts in a single line, various shaped components are used, which are conventionally divided into typical (corners, turns, splitters, "ducks", transitions, etc.) and non-standard (adapters for ventilation grilles or reducers for air exchange systems).
Air ducts made of polymers (plastic) in some cases can be an excellent alternative to metal counterparts. Among the advantages of plastic air ducts, it is necessary to highlight a small specific gravity, ease of installation (no need for special tools and fixtures), reasonable price. But plastic air ducts are not suitable for moving chemically aggressive gas-air mixtures.
There are rigid, semi-rigid and flexible plastic ducts. Rigid air ducts can be round or rectangular, while flexible and semi-rigid air ducts are only round in cross section.
Materials used in the manufacture of air ducts, basic technological processes and types of machines required for the implementation of this production cycle.
1. The dependence of the thickness of the walls of the duct on the area of its section.
2. The main types of machines required for the manufacture of steel galvanized air ducts.
The guillotine.
· Bending machine.
· Folding machine.
· Falseosadochny machine.
· Stiffening rib machine.
· Puklevochny machine.
ZIG machine.
· The device for production of works on spot welding.
· Spiral winding machine.
· The machine for production of branches of round section Gariloker (GORELOCKER).
· Rolling machine.
1. Materials used for the manufacture of galvanized steel air ducts.
Air ducts made of galvanized steel are mainly made from a sheet with a thickness of 0.5 - 1.2 mm, depending on their standard sizes, for example:
a rectangular air duct, ranging from 100x100 mm to 500x200 mm, is made of 0.5 mm thick galvanized steel sheet;
a rectangular air duct, ranging from 500x300 mm to 800x200 mm, is made of 0.7 mm thick galvanized steel sheet;
Rectangular air duct, from 800x300 mm up to 1000x1500 mm, is made of 1.2 mm thick galvanized steel sheet.
Used steel grade ST-3, ST-6.
2. The main types of machines required for the manufacture of steel galvanized air ducts:
Each machine is designed to perform one unique or several related technological operations for processing galvanized steel sheet, gradually turning it into a semi-finished product, a set of fittings and, finally, an air line ready for operation, consisting of a system of air ducts and ventilation equipment.
Guillotine.
The machine is designed to cut the steel sheet across the entire width of the roll and for nothing else. Structurally, it is a workbench on which a knife with a counterweight or an electric drive is mounted.
Bending machine.
The machine is intended for bending a steel sheet to the required angle (from 00 to 3600). Structurally, it is a bed with two guides, movable and fixed. The movable guide bends the sheet. The drive can be manual or electric.
Folding machine.
Designed for the production of several types of locks connecting the edges of a steel sheet, and, accordingly, for connecting different sections of straight-seam air ducts: single lock, double lock. Structurally, it is a frame with a rolling mechanism and an electric motor.
Folding machine.
This device is designed to tighten (settle) the corner at the junction of the extreme edges of two steel sheets, that is, to close the lock and obtain a tight connection between two adjacent sections of a straight-seam duct to each other.
Rib machine.
It is intended for the manufacture of stiffeners that serve to reduce the vibration of the duct walls during the passage of air and, accordingly, reduce noise. Air ducts, the walls of which are equipped with stiffeners, do not rattle during operation and “keep their shape” better.
Punch machine.
Serves for processing of places of connection of an air duct with a flange and giving them the necessary rigidity, durability and tightness. In fact, the machine presses through the sheets of the flange and air duct, ensuring the strength and immobility of their connection to each other.
ZIG machine.
Designed for the manufacture of the correct angles on the edges of the sheets at the points of attachment to the sections of the air ducts of the following fittings made of galvanized steel sheet: bends, half-bends, reductions and tie-ins. In fact, the machine performs flanging and preloading of the edges of parts previously cut from galvanized steel sheet on other types of machines, GORELOCKER, for example.
Apparatus for the production of work on spot welding.
Carries out welding operations for joining sheets of steel by spot welding. It is used for the manufacture of section transitions of galvanized steel air ducts, mixing and distribution chambers of central and duct air conditioners, silencer sections and adapters.
Spiral winding machine.
It is applied by production of air ducts of exclusively round section. The thickness of the steel sheet used for the manufacture of spirally wound air ducts directly depends on the cross-sectional area of the air duct - the larger the area, the thicker the sheet.
The air duct of circular section, starting from a diameter of 100 mm, and up to a diameter of 500 mm, is made of galvanized steel sheet with a thickness of 0.5 mm;
circular air duct, starting from a diameter of 500 mm, and up to a diameter of 900 mm is made of 0.7 mm thick galvanized steel sheet;
Circular air duct, from 900 mm in diameter up to 1250 mm in diameter, is made of 1 mm thick galvanized steel sheet.
The maximum allowable cross-sectional area of the air duct that this machine is able to digest is 1.13 m2, with a diameter of 1250 mm.
Gariloker (GORELOCKER).
The machine of this type is designed for cutting galvanized steel sheet into segments, and further manufacturing bends and half-bends with a diameter of 100 mm to 1250 mm inclusive.
rolling machine.
This device is designed for the production of round straight-seam air ducts. Allows to make shaped products and inserts from 50 mm long. up to 1250 mm. inclusive: adapters and section transitions (from rectangular to round, and vice versa). It is also possible to manufacture a straight section of the duct, however, its length will be limited to 1250 mm.
The machine park listed above is used in the production of galvanized steel air ducts and fittings of the following types:
- Straight-seam galvanized steel air ducts of square section with a length of 10 cm to 2.5 m inclusive;
- Straight-seam galvanized steel air ducts of circular cross section from 5 cm to 1.25 m long inclusive;
- Spiral-wound galvanized steel air ducts with a length of 50 cm to 5 m inclusive.
- Section transitions (designed to connect air ducts of various diameters and section shapes).
- Elbows (Designed to rotate the duct by 900, can be either round or square).
- Semi-bends (Designed to rotate the duct by 450, can be either round or square).
- Tees (Intended for dividing the air duct line into two parts of the same section, in a non-standard version it is possible to divide it into equal parts with a transition to a larger section, for example (100x100 / 100x100) / 200x100).
- Adapters (Intended for attaching gratings of both ceiling and wall types. A non-standard part that requires the development of an individual drawing. Structurally, the adapter is a steel box with an inset on top or side).
Reduction (A shaped part designed to switch from a main pipe to an air duct of a smaller diameter. Reductions of both rectangular and round sections are used. Structurally they are divided into straight tie-ins and saddle tie-ins. The length of the tie-in cannot be more than 20 cm).
Reminder: You can buy wholesale components and spare parts for industrial ventilation systems from us: fastening of air ducts, air conditioners, rectangular and round air ducts, traverse, mounting rail, galvanized corners, bracket for connecting flanges, mounting tape, perforated, tape clamp, aluminum tape, brackets, gratings and anemostats, sheet and roll insulation, galvanized metal sheets. We also produce wholesale trade fasteners: threaded studs, self-tapping screws, screws, bolts, screws, nuts, washers, rivets, drive-in anchors. Deliveries go throughout Russia, from a warehouse in Moscow.
For the manufacture of air ducts, metal, non-metallic and metal-plastic materials are used, as well as building structures. Materials for the manufacture of air ducts are selected depending on the characteristics of the medium transported through the air ducts.
| Materials for air ducts | ||
| Characteristics of the transported medium | Products and materials | |
| Air with a temperature not exceeding 80°C with a relative importance of not more than 60% | Concrete, reinforced concrete and gypsum ventilation blocks; plasterboard, gypsum concrete and wood concrete boxes; thin-sheet, galvanized, roofing, sheet, rolled, cold-rolled steel; fiberglass; paper and cardboard; other materials that meet the requirements of the specified environment | |
| The same, with a relative humidity of more than 60% | Concrete and reinforced concrete blocks; thin-sheet galvanized, sheet steel, sheet aluminum; plastic pipes and plates; fiberglass; paper and cardboard with appropriate impregnation; other materials that meet the requirements of the specified environment | |
| Air mixture with reactive gases, vapors and dust | Ceramic and pipes; plastic pipes and boxes; blocks of acid-resistant concrete and plastic concrete; metal-plastic; Sheet steel; fiberglass; paper and cardboard with protective coatings and impregnation corresponding to the transported medium; other materials that meet the requirements of the specified environment | |
Note: Air ducts made of cold-rolled and hot-rolled steel sheets must have a coating that is resistant to the transported medium.
Carbon steel of ordinary quality according to the rolling method is hot-rolled, if the workpiece is preheated, and cold-rolled, i.e. without heating the workpiece. According to the thickness, such steel is subdivided into thick sheets - 4 mm thick or more and thin sheets - up to 3.9 mm thick. Sheet steel with a thickness of 0.35 to 0.8 mm is called roofing.
hot rolled steel sheet manufactured in sheets 0.4...16 mm thick, 500...3800 mm wide, 1200... ...9000 mm long and in rolls 1.2...12 mm thick, 500...2200 wide mm. They are used for the manufacture of air ducts for general ventilation and aspiration.
sheet cold rolled steel are produced in sheets with a thickness of 0.35 ... 0.65 mm and in rolls with a thickness of 0.35 ... 3 mm. Used for the production of spiral-seam air ducts.
Galvanized sheet steel produced with a double-sided galvanized coating that protects steel from corrosion, in sheets 0.5 ... 3.0 mm thick, 710 ... 1500 mm wide. Used for the manufacture of only folded air ducts.
Thin sheet cold rolled carbon steel use a width of 100 ... 1250 mm, a thickness of 0.6 ... 2 mm.
Cold rolled low carbon steel strip thickness of 0.05 ... 4 mm, width up to 450 mm is used for the manufacture of spiral lock air ducts.
In the manufacture of air ducts and parts of ventilation systems, structural materials are widely used - sectional and shaped steel, as well as rolled aluminum.
flat steel produced in widths from 12 to 200 mm, thicknesses from 4 to 16 mm. These products are supplied in coils or strips, depending on the size. Flanges and fasteners are made from strip steel.
Angle Equal Shelf Steel profiles No. 2 ... No. 16 are made, which corresponds to the width of the shelf in centimeters; the thickness of such steel is from 3 to 20 mm. Frames, duct flanges are made of steel.
Non-ferrous metals
Aluminum- silver-white, light (ρ = 2700 kg/m3) and ductile metal. Interacting with atmospheric oxygen, aluminum is covered with a thin and durable film of aluminum oxide, which well protects the metal from corrosion. Folded and welded air ducts are made of aluminum.
aluminum sheets and aluminum alloys, produced with a thickness of 0.4 to 10 mm, a width of 400, 500, 600, 800 and 1000 mm, a length of 2000 mm, are used for the manufacture of air ducts and individual parts of ventilation systems.
The corners pressed from aluminum and aluminum alloys let out shelf width from 10 to 250 mm. With the same shelf width, the profiles can be of different thicknesses. Separate elements of network equipment are made from the corners.
Aluminum foil is produced with a thickness of 0.05 to 0.4 mm and is also supplied in rolls. Use foil for flexible corrugated air ducts. The height of the corrugation is 4 mm, the distance between the corrugations is 10 mm. Such air ducts are easily bent and serve for connection to local suctions.
Titanium- silvery-white refractory metal with high corrosion resistance (especially to acids), rather ductile, density ρ=4500 kg/m3. The high strength of titanium alloys is maintained at temperatures from -253 to +500 °C.
Commercially pure titanium grade VT1-00 or VT1-0, as well as low-alloy alloys of increased ductility grade ST4-0 or ST4-1 in the form of sheets with a thickness of 0.4 to 4 mm are used for the manufacture of air ducts. Air ducts made of titanium are usually welded.
Copper- viscous metal of a reddish color, heat and electrically conductive, plastic enough, which allows it to be processed by rolling, stamping, drawing. Copper in its pure form, as a rule, is not used in ventilation systems; usually alloys of copper with other metals are used. An alloy of copper and zinc is called brass. Compared to copper, brass is stronger, more ductile and harder, more resistant to corrosion and, when cast, has good mold filling.
Copper-zinc alloys (brass) are produced in seven grades: L96, L90, L85, L80, L70, L68, L62 (the numbers indicate the average percentage of copper in the alloy). Brass is used to make spark-proof ventilation equipment.
metal plastics
metal-plastic- structural material, which is a low-carbon cold-rolled sheet steel coated with a film. The industry produces metal-plastic of two types: with one- and two-sided coating.
Metal sheet with one-sided coating produced in the form of a steel tape with a thickness of 0.5 ... 1 mm, protected on one side with a polyvinyl chloride film with a thickness of (0.3 ± 0.03) mm. Metal-plastic is supplied in rolls with a strip width of (1000 ± 5) mm, weighing up to 5.5 tons. The outer diameter of the roll is not more than 1500 mm, the inner diameter is (500 ± 50) mm.
Double-sided coated metal is a steel tape with a thickness of 0.5 ... 0.8 mm, both sides of which are protected by a film of modified polyethylene with a thickness of 0.45 mm.
The metal-plastic has the properties inherent in metal and plastics; it is plastic, can be processed on the mechanisms that manufacture seam air ducts.
non-metals
Sheets of plasticized polyvinyl chloride) are made from an unplasticized polyvinyl chloride composition with the addition of auxiliary substances (stabilizers, lubricants, etc.) by film pressing or extrusion.
Sheets of unplasticized polyvinyl chloride are produced with a length of at least 1300 mm, a width of at least 500 mm. The thickness of the sheets depends on their brand and is for sheet vinyl plastic: VI - from 1 to 20 mm; VNE and VP - from 1 to 5 mm; VD - from 1.5 to 3 mm.
Sheet vinyl plastic has high mechanical strength, lends itself well to both manual and mechanical processing on conventional metal and woodworking machines. When heated, it acquires plasticity and is easily molded. After cooling the heated vinyl plastic, all its mechanical properties are restored. Viniplast is an electrically insulating material.
Sheet vinyl plastic is used in the manufacture of air ducts as an anti-corrosion material operating at temperatures from -20 to + 00 ° C.
Polyethylene- Synthetic polymer, dense, characterized by high chemical resistance. Apply at temperatures up to 60 ° C. A film for ventilation ducts is made from high-density polyethylene, which is delivered to the construction site in the form of a roll wound around a sleeve. 300...400 m of film up to 4000 mm wide and 30 to 200 microns thick are wound into a roll.
fiberglass- a material formed by interlacing mutually perpendicular strands of glass fiber. Flexible reinforced air ducts are made from fiberglass SPL impregnated with latex using glue and spring wire made of carbon steel with a diameter of 2 ... 2.5 mm.
textile materials
Types of air ducts
1. Round 2. Rectangular
Rice. 1. Details of duct networks:
1 - straight sections of round air ducts (a) and rectangular (b) sections;
II - branch nodes of round air ducts (in) and rectangular (r) sections;
III - bends and half-bends of round (d) and rectangular air ducts (e) sections;
IV - transitions;
1 - tee;
2 - transition;
3 - crosses;
4 - plug
Rice. 2. Unified details of round ducts: a- straight seam straight part; b - spiral locking straight part; shaped parts: in - bend 90 degrees; G- bend 30, 45, 60 degrees; d - symmetrical transition to B == 400 mm; e- asymmetrical transition from above AT= 400 mm; and- internal nipple, designed to connect the straight parts of the air ducts to each other; h - external nipple, designed to connect the fittings of air ducts to each other; and- end cap
Rice. 3. Unified details of rectangular ducts: a - straight part: fittings; b - bend 90 degrees; in- outlet 45 degrees; G - plug; d - duck; e- transition from a rectangular section to a round one; and - transition from rectangular to rectangular
3. Semi-oval
BUT - minor axis;
AT- major axle
Rice. 5. Shaped parts of semi-oval air ducts:
a - bend 90 degrees:
a1 - vertical;
a2- horizontal;
b - the transition is asymmetric;
in - the transition is symmetrical;
G - nipple internal;
d - plug;
e - tee;
and- insert in a circle;
h - transition from oval to round;
and - transition from oval to rectangular
4. Spiral lock
Rice. 6. Spiral lock air duct
Rice. 7. Installation diagram (a) for the production of spiral lock air ducts:
1 - decoiler,
2 - mechanism for cutting and welding the ends of the tape,
3 - belt degreasing mechanism,
4 - ribbon,
5 - profiling mill,
6 - mold head,
7 - spiral lock pipe
5. Spiral welded
Rice. 8. Spiral welded duct
6. Semi-rigid and textile
Rice. 9. Semi-rigid ducts:
a- circuit diagram semi-rigid duct;
b- semi-rigid air duct
Rice. 10. Textile air duct
7. Metal-plastic
Rice. 11. Air duct made of metal-plastic:
a -general form,
b - seam design,
c, g- two-sided and one-sided metal-layer,
1- PVC film,
2 - glue,
3 - steel tape
Seam connections
Rice. 12 Types of seam connections;
a - recumbent fold,
6 - recumbent fold with double cut-off,
c - corner fold,
g - corner seam connection with slotted latches,
d - standing fold,
e-zig connection,
g - rack connection
Rice. 13. Seam connection of round elements on the ridge
Rice. 14. Lying seam
Rice. 15. Standing seam
Rice. 16. Corner rebate
Figure 17. Pittsburgh (Moscow) fold
In the manufacture of air ducts, the sheets are interconnected:
- for welding (butt or overlap)
- on folds
Welded joints
Rice. 1.2.1 Welded joints:
a - butt, 6 - lap
Fig 19. Schemes for welding round ducts:
a - overlap,
6 - along the bent edges on one side,
c - along the bent edges on both sides
Rice. 18. Seam classification:
a - depending on the position of the parts to be welded,
6 - in the direction of efforts,
in - in length,
d - by degree of amplification
Rice. 20. Types of welded joints used in welding metal ducts:
a - a longitudinal seam for round and rectangular air ducts, paintings,
6 - annular seam for round bends,
c - welding of round flanges and fittings of rectangular air ducts,
e - welding of rectangular flanges and fittings,
e - welding of flanges of rectangular and round sections,
g - tacking of flanges of rectangular section,
h - welding of spirally welded air ducts,
and - welding of ventilation ducts
Rice. 21. Scheme of welding a section of a rectangular duct:
a - welding of knots,
6 - tacking the branch to the straight section
Rice. 22. Snap fold
Methods for connecting air ducts to each other
Flange connections
Corner flanges
Rice. 23. Angle steel flange
Flanges made of profiled galvanized tape
Rice. 24. Z-rail flange:
1 - Z-rail;
2 - C-rail;
3 - seal 8 x 15;
4 - inner corner;
5 - decorative corner
Rice. 25. Flange from profile type "tire"
Flat steel flange
Rice. 26. Flange made of strip steel for flanged air ducts with a diameter of 100 ... 375 mm
Sheet steel flange
Rice. 27. Sheet steel flange with flanges
Rice. 28. The position of the closing transverse end
rebate on round air ducts
Wafer connections
Fig.29. Flanged connection of rectangular ducts:
a, b- the sequence of preparation of air ducts;
in- section of the connection;
G- complete connection;
1 - lock profile;
2 - rubber compressor;
3 - kapron corner;
4 - decorative corner;
5 - connecting rail;
6 - stiffening corner
Socket (nipple) connection
Rice. 30. Nipple connection of round ducts
bandage connection
Rice. 31. Bandage connections of links of round air ducts:
a - with rubber seals;
b - with buteprol sealant;
in - on rivets;
g - with inserts during installation:
1 - bandage;
2 - sealant;
3 - steel corners;
5 - branch pipe;
6 - apron;
7 - air duct;
8 - bandage with buteprol sealant;
9 - bottom loop;
10 - buteprol
Telescopic connection
Rice. 32. Telescopic duct connection:
a - on self-cutting screws;
b - using combined rivets;
1 - self-tapping screw;
2 - rivet of one-sided riveting
Rice. 33. Connection of parts with one-sided riveting:
1,2 - details;
3 - rivet body;
4 - rod head;
5 - weakened section of the rod;
6 - riveter or pistol;
7 - collet riveter;
8 - rod.
Plank connection
Fig.34. Plank connection of steel
air ducts:
a - general view;
b - types of slats;
c - T-shaped rails
Production of round ducts
Rice. 2.1. Typical technological layout production site production of air ducts on a seam connection:
a - straight sections;
6 - fittings;
1- container for metal;
2 - marking table;
3 - guillotine shears;
4 - sheet bending mechanism;
5- rolling mechanisms;
6 - roller tables;
7 - containers for flanges;
8 - spot welding machine;
9 - folding mechanisms;
10- mechanisms for flanging;
11 - workbenches;
12 - painting conveyor;
13 - mechanism for
flanging of rectangular air ducts;
14 - welding transformer;
15 - false-sedimentary mechanism;
16 - cutting mechanism;
17 - mechanism for bending curved edges;
18 - sigmachine;
19 - mechanism for upsetting corner folds;
20 - selenium rectifier
Manufacturing sequence
| Working cycle | Operation | Equipment and tools | Operation sketch |
| Marking and cutting blanks | Trim both sides of a standard sheet at a 90° angle (if necessary) | Guillotine shears | |
| Mark the elements of the ventilation blank | Marking table, templates, scriber, ruler, compasses | ||
| Cut corners of elements | Pneumatic manual scissors | ||
| Rectilinear cutting of elements according to the markup | Guillotine shears | ||
| Curvilinear cutting of elements according to the markup | Die cutting mechanism | ||
| Procurement of semi-finished products | Roll rebate (straight) | Seam rolling mechanisms | |
| Roll curved seam and edge | Mechanism for forming curved edges | ||
| Roll (bend) elements of blanks | Rolling mechanisms | ||
| Sheet bending mechanisms | |||
| Cut out elements from the side to form a ridge and corrugation | Mechanisms for the manufacture of bends, ring templates, rollers | ||
| Assembly of elements | Assemble the ventilation blank, close and upset the fold | Seam upsetting mechanism | |
| Assemble the ventilation blank, close and upset the fold | Locksmith workbench; hammer | ||
| Assemble the ventilation blank on the ridges | Mechanism for making taps | ||
| Collect the elements of the parts on the rail and upset | Locksmith workbench, mallet, hammer | ||
| Flanging | |||
| Install the flanges on the ends of the assembled products and flange on the flange mirror or weld | Semi-automatic welding in environment with 2 | ||
| Coloring | Duct painting and drying | Painting conveyor | |
| Packing and marking | |||
| Stacking in a warehouse or in a container |