Manufacturing technology of air ducts description drawings. Air ducts. Technologies for the production of rectangular air ducts
Manufacturing on our own even small batches of air ducts required for equipping ventilation systems at various facilities, as a rule, is beneficial not only from an economic point of view. And if the company provides services for the provision of equipment for ventilation systems and performs their installation, the presence of its own production sites makes it possible to reduce prices and gain an advantage in the market.
Today, the production of air ducts can be carried out using several technologies and be organized in different ways geographically. As for the organization of production, it can be:
- Organized on a stationary production base;
- Be mobile and deploy directly at the facility where the ventilation system is being installed;
- Use combined approaches to organizing production.
Both the one and the other method of organizing production has its advantages, which ultimately allows you to reduce the cost finished products and transportation costs. For example, when working on large objects, it is often much more profitable to deliver machines and equipment to the site than to incur significant transportation costs for the transportation of air ducts manufactured in the main production.
Technologies for the production of rectangular air ducts
Air ducts of rectangular and square cross-section are often used for arranging ventilation systems and can be made using either welding or soldering, or using a mechanical lock. The very technology for the production of rectangular air ducts is quite simple and consists of several stages:
- First, a sheet of metal is cut according to the scan of the finished product;
- Then the finished workpiece is bent on a plate bending machine until it is given the required shape;
- Sealing of joints is carried out either using the folding lock technology, welding or soldering.
It should be noted that a mechanical lock is faster to manufacture and the manufacturing technology of such a joint is less laborious, its use leads to a slightly higher metal consumption. In addition, the joints of the duct turn out to be leaking and can worsen the performance of the ventilation system with a significant length. However, with a small thickness of a metal sheet, and therefore a low cost of an air duct, such a lock can be considered optimal for the manufacture of air ducts for ventilation hoses of small and medium length.
With a small thickness of the sheet from which the air duct is made, soldering can be used to achieve complete tightness of the structure. If the metal thickness is from 1.5 mm or more, a welded joint of the seam can be used.
Circular air ducts can be manufactured in two ways:
- By bending on a rolling machine with subsequent seam welding or using a folded lock;
- According to the technology of winding on a winding machine from a metal tape.
The rolling technology has almost the same features as the manufacture of rectangular air ducts. As for winding air ducts, the manufacturing process is simpler and does not require subsequent sealing of seams. In addition, winding air ducts can be made of non-standard lengths, which allows you to optimize costs in the manufacture of non-standard ventilation systems.
Materials used in the manufacture of air ducts, basic technological processes and types of machines required for the implementation of this production cycle.
1. Dependence of the duct wall thickness on its cross-sectional area.
2. The main types of machines required for the manufacture of steel galvanized air ducts.
· Guillotine.
· Bending machine.
· Folded rolling machine.
· Folding machine.
· Stiffening machine.
· Pucklevochny machine.
· ZIG machine.
· Apparatus for the production of work on spot welding.
· Spiral-wound machine.
· Machine for the production of round bends GORELOCKER.
· Rolling machine.
1. Materials used for the manufacture of galvanized steel air ducts.
Galvanized steel air ducts are mainly made of sheet with a thickness of 0.5 - 1.2 mm, depending on their standard sizes, for example:
rectangular duct, ranging from 100x100 mm, and up to 500x200 mm, is made of galvanized steel sheet 0.5 mm thick;
rectangular duct, ranging from 500x300 mm, and up to 800x200 mm, is made of galvanized steel sheet 0.7 mm thick;
rectangular air duct, ranging from 800x300 mm, and up to 1000x1500 mm, is made of galvanized steel sheet 1.2 mm thick.
The grade of the used steel is 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 transforming it into a semi-finished product, a set of shaped products and, ultimately, a ready-to-use air duct consisting of a system of air ducts and ventilation equipment.
Guillotine.
The machine is designed for cutting steel sheet across the entire width of the coil and 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 designed to bend steel sheet to the required angle (from 00 to 3600). Structurally, it is a frame with two movable and fixed guides. The movable guide bends the sheet. The drive can be manual or electric.
Folded rolling machine.
It is intended for the production of several types of locks connecting the edges of the steel sheet, and, accordingly, for connecting different sections of longitudinal seam 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 the longitudinal seam duct.
Stiffening machine.
It is intended for the manufacture of stiffening ribs, which 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 stiffening ribs, do not rattle during operation and “keep their shape” better.
Bulk machine.
Serves for processing the joints of the air duct with the flange and giving them the necessary rigidity, strength and tightness. In fact, the machine pushes the flange and air duct sheets, ensuring the strength and immobility of their connection to each other.
ZIG machine.
It is intended for the production of correct angles on the edges of sheets at the points of connection to the sections of air ducts of the following shaped products made of galvanized steel sheet: bends, semi-bends, reductions and tie-ins. In fact, the machine produces flanging and tightening of the edges of parts previously cut from galvanized steel sheet on other types of machines, for example, GORELOCKER.
Spot welding machine.
Carries out welding operations for joining steel sheets by spot welding. It is used for the manufacture of cross-section transitions of galvanized steel air ducts, mixing and distribution chambers of central and duct air conditioners, sections of silencers and adapters.
Spiral winding machine.
It is used in the manufacture of exclusively circular air ducts. The thickness of the steel sheet used for the manufacture of spiral-wound air ducts directly depends on the cross-sectional area of \u200b\u200bthe air duct - the larger the area, the thicker the sheet.
The circular air duct, starting from a diameter of 100 mm and up to a diameter of 500 mm, is made of galvanized steel sheet 0.5 mm thick;
a circular air duct, starting from a diameter of 500 mm and up to a diameter of 900 mm, is made of galvanized steel sheet 0.7 mm thick;
a circular air duct, from a diameter of 900 mm to a diameter of 1250 mm, is made of galvanized steel sheet 1 mm thick.
The maximum allowable cross-sectional area of \u200b\u200bthe air duct that this machine can digest is 1.13 m2, with a diameter of 1250 mm.
Garilocker (GORELOCKER).
The machine of this type is designed for cutting galvanized steel sheet into segments, and further production of bends and semi-bends with a diameter from 100 mm to 1250 mm inclusive.
Rolling machine.
This device is designed for the production of round longitudinal seam air ducts. Allows to manufacture fittings and inserts with a length of 50 mm. up to 1250 mm. inclusive: adapters and cross-section transitions (from rectangular to round, and vice versa). It is possible to manufacture a straight section of the air duct, however, its length will be limited to 1250 mm.
The above machine park is used in the production of galvanized steel air ducts and fittings of the following types:
- Straight-seam galvanized steel air ducts of square cross-section with a length of 10 cm to 2.5 m inclusive;
- Longitudinal steel galvanized circular air ducts with a length of 5 cm to 1.25 m inclusive;
- Spiral wound galvanized steel air ducts with a length of 50 cm to 5 m inclusive.
- Cross-section transitions (designed to connect air ducts of various diameters and cross-sectional 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 (Designed for dividing the air duct into two parts of the same section, in a non-standard version, it can be divided into equal parts with a transition to a larger section, for example (100x100 / 100x100) / 200x100).
- Adapters (Designed for attaching grilles of both ceiling and wall types. Non-standard detail requiring the development of an individual drawing. Structurally, the adapter is a steel box with a cut-in from the top or side).
Reduction (Shaped part intended for transition from a main pipe to an air duct of a smaller diameter. Reductions are used both rectangular and circular. Structurally, they are subdivided into straight inserts and saddle inserts. The insertion length cannot be more than 20 cm).
We remind: Here you can buy wholesale components and spare parts for industrial ventilation systems: fastening of air ducts, air conditioners, rectangular and round air ducts, traverse, mounting bus, galvanized corners, bracket for connecting flanges, mounting tape, perforated, tape clamp, aluminum tape, brackets, grilles and anemostats, sheet and roll insulation, galvanized metal sheets. And also we produce wholesale trade fasteners: threaded stud, self-tapping screws, screws, bolts, screws, nuts, washers, rivets, drop-in anchors. Deliveries go all over Russia, from a warehouse in Moscow.
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 for these purposes voids were specially left in the ceilings and walls, today ventilation communications are laid using ventilation ducts (they are also called air ducts, ventilation pipes). These are special tubular hollow structures that allow the distribution of supply air and the removal of polluted air.
Types of air ducts
The production of ventilation ducts can be quite a lucrative business, but first you need to decide what specific types of structures you want to make. Air ducts can be classified according to various criteria. So, depending on the shape, they distinguish round and rectangular ventilation boxesbased on the material used, structures can be plastic, steel (galvanized or stainless steel), aluminum, polyester, thermoplastic, silicone, fiberglass, and so on.
According to the presence of special properties, air ducts are divided into fireproof, stainless and others, according to the method of connection - 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 air ducts to produce
Manufacturing rectangular or round ventilation pipes from aluminum or steel is the easiest option. Such structures are faster and easier to install than plastic ones, and also have a lower cost price, 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, in offices, sports, educational, cultural and entertainment institutions, catering organizations and in general in any buildings where there are large premises, during the operation of which active air exchange is expected.
Manufacturing flexible ventilation ducts is a more complex process. They can be used only in specific conditions, for example, in rooms with complex configurations or in buildings where installation of ventilation using large galvanized ventilation pipes is not possible. Also, such structures are used in rooms where active ventilation systems cannot be provided, for example, hoods for removing hot air and acid vapors.
The cost of manufacturing ventilation pipes from rigid materials will require less, but it is necessary to start production with them not therefore, but because you can quickly implement such air ducts.
Manufacturing process
Structures of any kind are manufactured on special automatic devices. Basically, the production process is a conventional roll forming operation. We will not go into details on how to make a ventilation duct. After all, this is not done manually, but with the help 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 the ducts: rigidity, area and cross-sectional shape (based on the degree of demand in the market). We already talked about rigidity, so everything is clear with this. Flexible ventilation boxes can be realized more expensively 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 air flow rate, and, consequently, the noise level emitted by this flow in case of exceeding the speed standards.
Other selection factors
Round ventilation ducts are less labor-intensive to manufacture since they are fastened with snap-nipples. Also, such air ducts are faster and easier to install, because they have no 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 air flow in the room when a large cross-sectional area is required or when installation is carried out in conditions of increased complexity, for example, over suspended ceilings.
The manufacture of ventilation ducts of round and rectangular cross-section 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 equal demand.
However, if you want to make your business more successful, purchase ventilation equipment that includes both round and rectangular pipe production lines. What kind of cars do you need?
We equip a workshop for the production of air ducts
So, a technological line for the manufacture of ventilation ducts of any section should include:
- feeding device;
- an automatic machine for unwinding a metal roll sheet;
- a device for straightening a sheet (the technology allows a deviation of the diagonal of both the blank sheet and the duct itself by 0.8 millimeters - if the ventilation pipe has a strong violation of the geometry, then a strong noise will be emitted from the air flow, therefore, modern technology without fail includes a straightening device );
- industrial numerical control system;
- a guillotine that cuts off the finished duct.
The line used for the manufacture of rectangular and round ventilation pipes differs only in that in the first case, the shaping units are angular notches, a system for applying rib stiffness, an automatic sheet-folding equipped with a swivel beam, and in the second - rolling rollers.
Process line cost
The production of ventilation ducts is quite costly. A line for the manufacture of circular air 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 range from 1.8 million rubles and more. That is, in order to purchase both lines, you need to have in stock no less than 3.3 million rubles by the very minimum standards.
Payback period
But there is good news too. The profitability in this area of \u200b\u200bbusiness is quite high. And if you release a running 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 will be able to recoup the costs in six months.
Development prospects
The production of ventilation ducts is a promising business. Having established technological process, you can expand your business and also engage in the manufacture of connecting and fastening accessories for pipes: plugs, nipples, "umbrellas", tie-ins, mounting punched tape and others. Such products can be produced from substandard goods, scraps and other waste.
In addition, try to enrich your 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 for ventilation systems.
Having worked steadily for at least six months and having thoroughly prepared the technological base, you can, among other things, start organizing services for the design and installation of ventilation systems. To do this, you will need to hire engineers specialized in heat and gas supply work.
These are specialists in demand 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 so highly valued, it is believed that these are low-skilled workers, and sometimes they may not have any qualifications at all. Having recruited staff, you can offer services for the installation of ventilation systems.
Air duct production
Boxes for ventilation and air conditioning systems are used in the construction of any channel systems. The material for their manufacture is selected depending on the actual operating conditions, the parameters of the working environment, as well as on the purpose. For manufacture of air ducts use low-carbon steel, "galvanized" or "stainless steel", as well as different kinds plastic.
Air ducts for ventilation from "galvanized" are used in air exchange systems with a working environment of up to + 80C (possibly a short rise to + 200C) and humidity up to 60%. Galvanized steel air ducts can be used in areas with any climate in accordance with GOST 15150, provided that the working media are not aggressive (air and gas-air). Galvanized air ducts do without additional protective coating, since the top zinc layer protects the metal from corrosion even in places of damage (due to galvanic steel-zinc pair, which forms an oxide film under the influence of atmospheric oxygen).
Stainless steel air ducts are designed to work with overheated air and aggressive gas-air mixtures. Working environment temperature - up to + 500C (short-term increase up to + 70C is allowed). Steel according to GOST 5632-72 (heat- and corrosion-resistant) is used as a blank material for the production of stainless steel air ducts.
"Black" air ducts are made of low-carbon steel. Workpiece thickness - from 1.2 to 15 mm. "Black" ventilation ducts tolerate high temperatures and exposure to open flames well (they are weakly susceptible to deformation - the ventilation system ducts will not depressurize, and the fire will not spread to neighboring rooms).
For aspiration systems and smoke extraction "black" ventilation ducts are the right choice. Ventilation systems made of plain carbon steel are mainly in demand for production areaswhere excessive gas, dust, etc.
Air ducts can be round or rectangular in cross section... The production of rectangular air ducts is a classic of ventilation systems, but thanks to progressive technologies, the market is increasingly giving way to round air ducts, since they are more technologically advanced in manufacturing, have better aerodynamic performance and easy to install. Today, 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 subdivided into typical (corners, turns, splitters, "ducks", transitions, etc.) and atypical (adapters for ventilation grilles or reducers for air exchange systems).
In some cases, air ducts made of polymers (plastic) can become an excellent alternative to metal counterparts. Among the advantages of plastic air ducts, it is necessary to highlight a low specific weight, ease of installation (no need for special tools and devices), and a reasonable price. But plastic air ducts are not suitable for moving chemically aggressive gas-air mixtures.
There are rigid, semi-rigid and flexible plastic air ducts. Rigid air ducts can be circular or rectangular, while flexible and semi-rigid air ducts have only a circular cross-section.
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.
| Duct materials | ||
| Characteristics of the transported medium | Products and materials | |
| Air with a temperature of no more than 80 ° C with a relative importance of no more than 60% | Concrete, reinforced concrete and gypsum ventilation blocks; gypsum plasterboard, gypsum concrete and wood concrete boxes; sheet, galvanized, roofing, sheet, coil, 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; galvanized sheet steel, 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; metalloplast; 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 by the rolling method is hot-rolled, if the billet is preheated, and cold-rolled, i.e. without heating the workpiece. In terms of thickness, such steel is subdivided into thick-sheet steel - with a thickness of 4 mm or more and thin-sheet steel - up to 3.9 mm thick. Thin sheet steel with a thickness of 0.35 to 0.8 mm is called roofing.
Hot rolled sheet steel made in sheets with a thickness of 0.4 ... 16 mm, width 500 ... 3800 mm, length 1200 ... ... 9000 mm and in rolls with a thickness of 1.2 ... 12 mm, width 500 ... 2200 mm. They are used for the manufacture of air ducts for general ventilation and aspiration.
Cold rolled steel sheet made in sheets with a thickness of 0.35 ... 0.65 mm and in rolls with a thickness of 0.35 ... 3 mm. They are used for the production of spiral-seam air ducts.
Galvanized sheet steel produced with a double-sided galvanized coating, which protects steel from corrosion, in sheets 0.5 ... 3.0 mm thick, 710 ... 1500 mm wide. They are used for the manufacture of folded air ducts only.
Cold rolled carbon steel sheet used with a width of 100 ... 1250 mm, a thickness of 0.6 ... 2 mm.
Cold Rolled Low Carbon Steel Strip 0.05 ... 4 mm thick, up to 450 mm wide are used for the manufacture of spiral-lock air ducts.
In the manufacture of air ducts and parts of ventilation systems, construction materials are widely used - section and shaped steel, as well as rolled aluminum.
Strip steel produced in width from 12 to 200 mm, thickness from 4 to 16 mm. These products are delivered in skeins or strips, depending on the size. Flanges and fasteners are made of strip steel.
Angle equal steel make profiles No. 2 ... No. 16, which corresponds to the width of the shelf in centimeters; the thickness of such steel is from 3 to 20 mm. Frames and air duct flanges are made of steel.
Non-ferrous metals
Aluminum - silvery white, light (ρ \u003d 2700 kg / m3) and ductile metal. By interacting with oxygen in the air, aluminum is covered with a thin and durable film of aluminum oxide, which protects the metal well from corrosion. Seamed and welded air ducts are made of aluminum.
Sheets of aluminum 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.
Extruded corners of aluminum and aluminum alloys are produced with shelf widths from 10 to 250 mm. With the same flange width, the profiles can have different thicknesses. Separate elements of network equipment are made from the corners.
Aluminum foil produced with a thickness of 0.05 to 0.4 mm and supplied in rolls. Use foil for flexible corrugated 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 suction units.
Titanium - a silvery-white refractory metal with high corrosion resistance (especially to acids), sufficiently ductile, with a density ρ \u003d 4500 kg / m3. The high strength of titanium alloys remains at temperatures from -253 to +500 ° C.
Technically pure titanium grade VT1-00 or VT1-0, as well as low-alloyed alloys of increased ductility grade CT4-0 or CT4-1 in the form of sheets with a thickness of 0.4 to 4 mm are used for the manufacture of air ducts. Titanium air ducts are generally welded.
Copper - ductile reddish metal, heat and electrically conductive, sufficiently ductile, which allows it to be processed by rolling, stamping, and drawing. As a rule, pure copper is not used in ventilation systems; usually use copper alloys with other metals. An alloy of copper and zinc is called brass. Compared to copper, brass is stronger, more ductile and harder, more resistant to corrosion and has good mold filling during casting.
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). Spark-proof ventilation equipment is made of brass.
Metal-reinforced plastics
Metalloplast- structural material, which is a low-carbon cold-rolled sheet steel covered with a film. The industry produces metal-plastic of two types: with one- and two-sided coating.
Metalloplast with one-sided coating produced in the form of a steel tape 0.5 ... 1 mm thick, protected on one side with a polyvinyl chloride film with a thickness of (0.3 ± 0.03) mm. Metalloplast 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.
Metalloplast with double-sided coating is a steel tape 0.5 ... 0.8 mm thick, both sides of which are protected by a modified polyethylene film with a thickness of 0.45 mm.
Metalloplast possesses properties inherent in metal and plastics; it is plastic, it can be processed on mechanisms that manufacture folded air ducts.
Nonmetals
Sheets made of plasticized polyvinyl chloride (vinyl plastic sheet) are made from non-plasticized polyvinyl chloride composition with the addition of auxiliary substances (stabilizers, lubricants, etc.) by pressing films 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.
Vinyl plastic sheet has high mechanical strength, lends itself well to both manual and mechanical processing on conventional metal-woodworking machines. When heated, it acquires plasticity and is easily molded. After cooling the heated vinyl plastic, all of it mechanical properties are restored. Viniplast is an electrical insulating material.
I use sheet vinyl plastic in the manufacture of air ducts as an anticorrosive material operating at temperatures from -20 to + 00 ° C.
Polyethylene - synthetic polymer, dense, characterized by high chemical resistance. Applied at temperatures up to 60 ° C. High-density polyethylene is used to produce a film for ventilation ducts, which is delivered to the construction site in the form of a roll wound on a sleeve. A roll is wound 300 ... 400 m of film up to 4000 mm wide, with a thickness of 30 to 200 microns.
Fiberglass - a material formed by interlacing mutually perpendicular strands of glass fibers. Flexible reinforced air ducts are made of SPL fiberglass, impregnated with latex, using glue and spring wire from carbon steel with a diameter of 2 ... 2.5 mm.
Textile materials
Types of air ducts
1. Round 2. Rectangular
Figure: 1. Details of air duct networks:
1 - straight sections of round air ducts (and)and rectangular (b) sections;
II - nodes of branches of round ducts (in)and rectangular (d) 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
Figure: 2. Standardized parts for circular air ducts: and- longitudinal seam straight part; b -spiral lock straight part; fittings: in -bend 90 degrees; r- bend 30, 45, 60 degrees; d -transition symmetrical to B \u003d\u003d 400 mm; e-transition asymmetrical over IN\u003d 400 mm; f- internal nipple, designed to connect straight parts of air ducts to each other; s -external nipple, designed to connect the fittings of air ducts to each other; and- end cap
Figure: 3. Unified details of rectangular air ducts: and -straight part: fittings; b -bend 90 degrees; in- outlet 45 degrees; r -stub; d -duck; e- transition from rectangular section to round; f -transition from rectangular section to rectangular
3. Semi-oval
AND -minor axis;
IN- major axis
Figure: 5. Shaped parts of semi-oval air ducts:
and -bend 90 degrees:
a1 -vertical;
a2- horizontal;
b -asymmetrical transition;
in -the transition is symmetrical;
r -internal nipple;
d -stub;
e -tee;
f- inset in a circle;
s -transition from an oval section to a round one;
and -transition from oval to rectangular
4. Spiral-lock
Figure: 6. Spiral-lock air duct
Figure: 7. Installation diagram (and)for the production of spiral-lock air ducts:
1 - decoiler,
2 - a mechanism for cutting and welding the ends of the strip,
3 - belt degreasing mechanism,
4 - tape,
5 - roll forming mill,
6 - forming head,
7 - spiral-lock pipe
5. Spiral-welded
Figure: 8. Spiral-welded duct
6. Semi-rigid and textile
Figure: 9. Semi-rigid air ducts:
and- schematic diagram of a semi-rigid air duct;
b- semi-rigid air duct
Figure: 10. Textile duct
7. Reinforced plastic
Figure: 11. Air duct made of metal-plastic:
and -general form,
b -seam design,
c, d- double-sided and one-sided metal-plastic,
1- polyvinyl chloride film,
2 - glue,
3 - steel tape
Folded joints
Figure: 12 Types of folded joints;
a - recumbent fold,
6-fold double cut-off fold,
в - corner fold,
g - corner seam connection with grooved latches,
d - standing seam,
e-zig connection,
w-lath connection
Figure: 13. Seam connection of round elements on a zig
Figure: 14. Reclining fold
Figure: 15. Standing fold
Figure: 16. Corner fold
Figure 17 Pitsburgh (Moscow) fold
In the manufacture of air ducts, the sheets are interconnected:
- welded (butt-welded or overlapped)
- on the folds
Welded connections
Figure: 1.2.1 Welded connections:
a - butt, 6 - overlap
Fig. 19. Diagrams of welding round air ducts:
a - overlap,
6 - along the bent edges on one side,
c - along the bent edges on both sides
Figure: 18. Classification of seams:
a - depending on the position of the parts to be welded,
6 - in the direction of efforts,
c - in length,
d - by the degree of amplification
Figure: 20. Species welded jointsused in welding metal air ducts:
a - longitudinal seam for circular and rectangular air ducts, paintings,
6 - circular seam for round bends,
c - welding of round flanges and fittings of rectangular air ducts,
d - welding of rectangular flanges and fittings,
e - welding of flanges of rectangular and round sections,
g - tacking of rectangular flanges,
h - welding of spiral-welded air ducts,
and - welding of ventilation ducts
Figure: 21. Welding scheme of a rectangular duct section:
a - welding of nodes,
6 - tacking a branch to a straight section
Figure: 22. Snap fold
Methods for connecting air ducts to each other
Flange connections
Angle flanges
Figure: 23. Angle steel flange
Flanges made of profiled galvanized tape
Figure: 24. Z-bar flange:
1 - Z-rail;
2 - C-rail;
3 - seal 8 x 15;
4 - inner corner;
5 - decorative corner
Figure: 25. Flange made of profile "tire"
Strip steel flange
Figure: 26. Flange made of strip steel for flanged air ducts with a diameter of 100 ... 375 mm
Sheet steel flange
Figure: 27. Flange made of sheet steel with collars
Figure: 28. The position of the closing transverse end
seam on round air ducts
Wafer connections
Fig. 29. Wafer connection of rectangular air ducts:
a, b- sequence of preparation of air ducts;
in- connection section;
r- connection assembly;
1 - lock profile;
2 - rubber compressor;
3 - nylon corner;
4 - decorative corner;
5 - connecting rail;
6 - corner of rigidity
Socket (nipple) connection
Figure: 30.Nipple connection of circular ducts
Bandage connection
Figure: 31. Bandage connections of round duct links:
a - with rubber seals;
b - with a butteprol sealant;
c - riveted;
d - with inserts during installation:
1 - bandage;
2 - sealant;
3 - steel corners;
5 - branch pipe;
6 - an apron;
7 - air duct;
8 - bandage with buteprol sealant;
9 - bottom loop;
10 - buteprol
Telescopic connection
Figure: 32. Telescopic duct connection:
a - on self-cutting screws;
b - using combined rivets;
1 - self-tapping screw;
2 - blind rivet
Figure: 33. Joining parts with one-sided riveting:
1,2 - details;
3 - rivet body;
4 - rod head;
5 - weakened section of the rod;
6 - riveter or gun;
7 - rivet collet;
8 - rod.
Bar connection
Fig. 34. Steel bar connection
air ducts:
a - general view;
b - types of planks;
c - T-shaped slats
Production of round ducts
Figure: 2.1. Typical technological layout of the production area for the manufacture of rebated air ducts:
a - straight sections;
6 - fittings;
1- container for metal;
2 - marking table;
3 - guillotine scissors;
4 - bending mechanism;
5- rolling mechanisms;
6- roller tables;
7 - containers for flanges;
8 - spot welding machine;
9 - folded rolling mechanisms;
10- mechanisms for flanging;
11- workbenches;
12 - painting conveyor;
13 - mechanism for
flanging of rectangular air ducts;
14 - welding transformer;
15 - folding mechanism;
16 - die-cutting mechanism;
17 - mechanism for bending curved edges;
18 -zig machine;
19 - mechanism for upsetting corner seams;
20 - selenium rectifier
Manufacturing sequence
| Work cycle | Operation | Equipment and tools | Operation sketch |
| Marking and cutting blanks | Cut a standard sheet at a 90 ° angle on both sides (if necessary) | Guillotine shears | |
| Mark the elements of the ventilation blank | Marking table, templates, scribe, ruler, compasses | ||
| Cut out corners of elements | Manual pneumatic scissors | ||
| Straight line cutting of elements according to marking | Guillotine shears | ||
| Curvilinear cutting of elements by marking | Die cutting mechanism | ||
| Procurement of semi-finished products | Roll seam (straight) | Folded rolling mechanisms | |
| Roll a curved seam and an edge | Curved edge forming mechanism | ||
| Roll (bend) workpiece elements | Rolling mechanisms | ||
| Sheet bending mechanisms | |||
| Cut elements from the drawer side to form a ridge and corrugation | Mechanisms for the production of bends, ring templates, rollers | ||
| Assembling elements | Assemble the ventilation blank, close and close the fold | Fold upsetting mechanism | |
| Assemble the ventilation blank, close and close the fold | Locksmith's workbench; hammer | ||
| Assemble the ventilation blank on the zig | Mechanism for making bends | ||
| Collect elements of parts on the rail and besiege | Locksmith workbench, mallet, hammer | ||
| Flanging | |||
| Install the flanges on the ends of the assembled products and flange onto the flange mirror or weld | Semi-automatic welding in the environment with 2 | ||
| Coloration | Air duct painting and drying | Paint conveyor | |
| Picking and marking | |||
| Stacking in a warehouse or in a container |