AIR DUCT

Nguyễn Mai Bích TiênVũ Hoàng Thủ

AIR DUCT SYSTEM

CK05BNHAIR DUCT SYSTEM

2

1. DUCT CONSTRUCTION MATERIALS

2. DUCT CONFIGURATIONS

3. VINADUCT SYSTEM

4. DUCTWORK INSULATION

5. DUCTWORK INSTALLATION

metal

polythene

Textile/fabric

flexible

- Galvanized steel sheet- Stainless steel- Power coating sheet-Prepainted steel sheet- Mild steel-Aluminium


3



3. VINADUCT SYSTEM




4



3. VINADUCT SYSTEM




polythene

inflatable polythene ducts

steel wires

Rows of small holes in the sides of the ducts



3. VINADUCT SYSTEM



http://images.google.com.vn/imgres?imgurl=http://www.cnhuaxing.cn/cp/1.jpg&imgrefurl=http://www.cnhuaxing.cn/Ecpzs4.html&usg=__SwcS4ZKKo2LcV6O7UCuv56bhnRE=&h=470&w=500&sz=205&hl=vi&start=4&um=1&tbnid=FoMOxQqUL108jM:&tbnh=122&tbnw=130&prev=/images?q=steel+wire&imgtype=photo&as_st=y&hl=vi&lr=lang_vi&sa=G&um=1

http://images.google.com.vn/imgres?imgurl=http://img.alibaba.com/photo/200088282/Hot_Rolled_Mild_Steel_Wire_Rod_in_Coils.jpg&imgrefurl=http://xiantong.en.alibaba.com/product/200088282-50353690/Hot_Rolled_Mild_Steel_Wire_Rod_in_Coils.html&usg=__UDnGR7Dob-rQBeR4tsafBTY1Axg=&h=500&w=475&sz=105&hl=vi&start=12&um=1&tbnid=vdPVJTGxe0YjAM:&tbnh=130&tbnw=123&prev=/images?q=steel+wire&imgtype=photo&as_st=y&hl=vi&lr=lang_vi&sa=G&um=1

http://images.google.com.vn/imgres?imgurl=http://www.homesteadmetals.com/images/Photos/SteelWire.jpg&imgrefurl=http://www.homesteadmetals.com/photos.html&usg=__7aW_rVf0JCZRAufB_PKGpktI2mM=&h=400&w=600&sz=112&hl=vi&start=2&um=1&tbnid=eD7hWndAL2HARM:&tbnh=90&tbnw=135&prev=/images?q=steel+wire&imgtype=photo&as_st=y&hl=vi&lr=lang_vi&sa=G&um=1


6



3. VINADUCT SYSTEM




7

COMPARED TO TRADITIONAL METAL DUCTWORK ACTIVAIR AIR DUCTING HAS MANY ADVANTAGES

Activair air ducting Traditional metal ductwork

Low capital and installation costVery inexpensive to purchase.Easy to install.Quick installation - typically 80% faster than metal ductwork.

High costExpensive to purchase.Requires specialist installation.4/5 times the man hours to install compared to Activair air ducts.

LightweightEasy to handle and install.Minimal load on building structure.Easily shipped using low cost carriers.

HeavySpecialist handling and lifting equipment required.Strong suspension points needed, structure may need strengthening.Transport costs high.



3. VINADUCT SYSTEM




8

Low maintenanceActivair air ducting will never rust, corrode or rot.Activair air ducts are resistant to most chemicals, moisture, dust and airborne particles.

High maintenanceSusceptible to rust, corrosion and rot.Requires expensive specialist cleaning.

Even air distributionLarge numbers of small holes create balanced air distribution.Draft free ventilation. Even temperatures throughout the building

Spot air distributionAir distribution limited by diffuser and grille positioning.Drafts and hot spots caused by diffusers

COMPARED TO TRADITIONAL METAL DUCTWORK ACTIVAIR AIR DUCTING HAS MANY ADVANTAGES1. DUCT CONSTRUCTION MATERIALS


3. VINADUCT SYSTEM




9

COMPARED TO TRADITIONAL METAL DUCTWORK ACTIVAIR AIR DUCTING HAS MANY ADVANTAGES

Low noiseQuiet air diffusion from multiple outlets. Activair air ducts dampen sound.

High noiseNoise caused by faster air movement at less outlets.Metal air ducts can vibrate and amplify air and fan noise.

Temporary/Portable InstallationActivair air ducts roll up and store when not required.Quick removal and re-installation.

Permanent/Fixed InstallationBulky, difficult to dismantle for storage. Time consuming to remove and re-erect.

FlexiblePasses easily around obstructions - joists, piping, trusses, etc.Activair air ducts deform to pass through tight spaces, between obstructions etc.

RigidComplex designs are needed to avoid obstructions.Metal air ducts do not deform.



3. VINADUCT SYSTEM



CK05BNH

Textile/fabric

AIR DUCT SYSTEM

http://images.google.com.vn/imgres?imgurl=http://upload.ecvv.com/upload/Product/20084/China_DurkeeSox_fabric_ducts_fabric_air_ducts20084171705464.jpg&imgrefurl=http://www.ecvv.com/product/vp1243376/DurkeeSox-fabric-duct-fabric-air-duct.html&usg=__jLUxamM7CFj4fWgVB5aBBxO3smc=&h=899&w=1197&sz=85&hl=vi&start=4&um=1&tbnid=QzfxfiDBNtelXM:&tbnh=113&tbnw=150&prev=/images?q=textile+fabric+duct&hl=vi&lr=lang_vi&um=1

CK05BNH

flexible

AIR DUCT SYSTEM

http://images.google.com.vn/imgres?imgurl=http://www.zgjitai.com/uploadfiles/FLEXIBLE%20DUCT%20CONNECTORS_7.jpg&imgrefurl=http://www.zgjitai.com/ten/product.asp?id=8417&usg=__dEN2q3DdkJftp9eFs9ZO8kr0kiU=&h=347&w=635&sz=67&hl=vi&start=28&um=1&tbnid=onquPHw6YYgQ9M:&tbnh=75&tbnw=137&prev=/images?q=flaxible+duct&ndsp=20&hl=vi&lr=lang_vi&sa=N&start=20&um=1

http://images.google.com.vn/imgres?imgurl=http://www.made-in-china.com/image/2f0j00QedtisrfgIobM/Aluminum-Flexible-Ducts.jpg&imgrefurl=http://www.made-in-china.com/showroom/cnhzhc/product-detailJoOElKpAYPVc/China-Aluminum-Flexible-Ducts.html&usg=__UDhLJP483d_O89x00fP_5pRTzTU=&h=478&w=499&sz=51&hl=vi&start=32&um=1&tbnid=_JfTco0WtRQW5M:&tbnh=125&tbnw=130&prev=/images?q=flaxible+duct&ndsp=20&hl=vi&lr=lang_vi&sa=N&start=20&um=1

http://images.google.com.vn/imgres?imgurl=http://www.wmccm.co.uk/WMCCM-Images/CatalogImages/39/R-FD-16/Flex-duct.jpg&imgrefurl=http://www.wmccm.co.uk/WMCCM/DesktopDefault.aspx?tabindex=1&tabid=3038&usg=__F65S-qdsGA7zjhl7P43-TJq623Y=&h=703&w=933&sz=96&hl=vi&start=48&um=1&tbnid=DFT6ehwFSLSjnM:&tbnh=111&tbnw=147&prev=/images?q=flaxible+duct&ndsp=20&hl=vi&lr=lang_vi&sa=N&start=40&um=1

http://images.google.com.vn/imgres?imgurl=http://www.made-in-china.com/image/2f0j00sCFESaURsGqYM/Insulated-Flexible-Duct.jpg&imgrefurl=http://www.made-in-china.com/showroom/cathyleen/product-detailSMNnBJtTvaVA/China-Insulated-Flexible-Duct.html&usg=__f-dC1-jJzDgLiPO6kIHV-SbpgjI=&h=1170&w=1816&sz=94&hl=vi&start=50&um=1&tbnid=RnqNFeNfYIlJuM:&tbnh=97&tbnw=150&prev=/images?q=flaxible+duct&ndsp=20&hl=vi&lr=lang_vi&sa=N&start=40&um=1


12



Rectangular air duct Round Duct Flat Oval Duct

3. VINADUCT SYSTEM



Advantage

- Provides the greatest cross-sectional area (ie air carrying capacity) of any of the duct families for any given maximum width or height dimension.

- Simplicity, ease of manufacture and corresponding economy of its fittings.

- Every conceivable transition and fitting can be fabricated in the rectangular format and done so inexpensively--often with only four pieces, which pieces may be computed and automatically cut from sheet metal stock

- The edges of the several constituent pieces that define the fitting may be brake or machine-formed to create a Pittsburgh, snap-lock or similar seam whereby the fitting may be expeditiously assembled without resort to welding or similar time-consuming attachment measures


13

Short coming

- The short lengths of duct sections available and the relative complexity of manufacture of such straight sections

- Straight sections of virtually any length could, in theory, be made simply by rolling out sufficient stock, only certain size ducts may be thus fabricated within the five foot width constraint without substantial sheet metal waste

- The tradeoff is duct the maximum length of which is the width of the coil stock employed



Rectangular air duct Round Duct Flat Oval Duct

3. VINADUCT SYSTEM




14

Advantage

- Literally wound as a solid helix from a relatively narrow coil of about six inches in width

- The diameter of the finished circular duct is that of the solid helix and may be any reasonable diameter

- The absence of length restrictions such as found with rectangular duct, at least aside from the obvious practicalities of handling excessively long duct sections

- Any length duct may be fabricated by continuing the helical winding process until the desired length is reached


2. DUCT CONFIGURATIONS Rectangular air duct Round Duct

Flat Oval Duct

3. VINADUCT SYSTEM




15



Flat Oval Duct

3. VINADUCT SYSTEM



- Least efficient in terms of conveying air volume, at least when confronted with a finite space limitation--the usual situation

- Fills` this full height only in the center thereof, leaving unused dead spaces in what would be the corners of a rectangular (square) duct of the same lineal cross-sectional dimension

Short coming


16



Flat Oval Duct

3. VINADUCT SYSTEM




17



Flat Oval Duct

3. VINADUCT SYSTEM



- Comes closer to approximating the air carrying capacity of rectangular duct while not, as noted, sacrificing the advantages obtained from circular duct

- Fittings for flat-oval duct are considerably more difficult to manufacture than corresponding rectangular fittings

- The continuously curved edges that define these gore sections renders the machine formation of seams difficult and expensive

Advantage

Short coming


18





3. VINADUCT SYSTEM

Bends

T,X,Y pieces Reducers Dampers


19





3. VINADUCT SYSTEM

Bends



20





3. VINADUCT SYSTEM

Bends


CK05BNH

21

Air duct system


22





3. VINADUCT SYSTEM

Bends



23

The connection piece (Фd3) on the BBKCL is intended for fitting end caps (EPFH) to allow inspection or cleaning





3. VINADUCT SYSTEM

Bends



24

…… ……





3. VINADUCT SYSTEM

Bends



25

The measuring bend has two measuring connectors, each phaced in its own cup, which allows up to 50 mm of insulation. Measuring bends are suitable for measuring in the regulation situation, but also for continuous control measurement of the volume flow. The measuring bend can be included as a permanent measuring point as early as the planning stage

•Measuring the air flow is very easy. Simply remove the plastic caps from the measuring connectors and install the measuring tubes.•The differential pressure can be read off a manometer





3. VINADUCT SYSTEM

Bends



26

With an asymmetrical velocity profile, measurement values may deviate from the ideal. The measuring bend should, therefore, not be placed immediately after a damper, bend or t-piece.Reducers have a negligible effect on measurement values





3. VINADUCT SYSTEM

Bends



28





3. VINADUCT SYSTEM

Bends



29





3. VINADUCT SYSTEM Bends

T,X,Y pieces

Reducers Dampers


30






T,X,Y pieces

Reducers Dampers


31






T,X,Y pieces

Reducers Dampers


32






T,X,Y pieces

Reducers Dampers


33






T,X,Y pieces

Reducers Dampers


34






T,X,Y pieces

Reducers Dampers


35






T,X,Y pieces

Reducers Dampers


36





3. VINADUCT SYSTEM Bends T,X,Y pieces

Reducers

Dampers

3 step reduction

2 step reduction

1 step reduction


37






Reducers

Dampers

38


39






Reducers

Dampers


40






Reducers

Dampers

41


42

The damper cup has marks showing the position of the damper blade between 0 and 90. The damper blade can also be locked in position with screwsThe damper cup allows for up to 50 mm of insulating material






Reducers

Dampers


43





3. VINADUCT SYSTEM Bends T,X,Y pieces Reducers

Dampers


44

The PSDRL is like the TDRL, but has a PSL take off. This means that the damper can be easily incorporated into an existing duct system. Inspection and cleaning of the ventilation system is very easy because the damper and cleaning hatch because the damper and cleaning hatch can be removed quickly.

The TDRL damper consists of a cleaning hatch, a fitted damper blade and a T-pipe in the branch of which the cleaning hatch can be fitted with precision






Dampers


45






Dampers


46






Dampers


47

The DSL is a closing damper for use when complete closure of the air flow is not required

The DTL is a closing damper for use when complete closure of the air flow is required






Dampers


48

The damper cup is fitted with a handle making continuous adjustment possible between 0 and 90o

The damper cup is fitted with a cross-arm for mounting 2 wire, making remote control possible.






Dampers


49






Dampers


50






Dampers


51

The angle of rotation can be set by mechanical restriction. The motor is protected against overloading, and stops automatically when it reaches its own limitThe damper can be turned manually using the built-in release button on the motorIf fitted outdoor, the motor should be protected against direct UV radiation and rain






Dampers


52






Dampers


53

The motor is a quick-turn on/off damper motor, developed specially for use in local ventilation systems requiring rapid opening and closing of dampers at extraction points.The motor is a quick-turn modulating damper motor, developed specially for use in fume cupboards and laboratory ventilation systems requiring rapid changes of volume flow and a modulating, precise control of the air






Dampers


54

A pre-set spring is also fitted, and will be released in case of a total power failure. The spring is re-set when the mains voltage is re-connected






Dampers


55



3. VINADUCT SYSTEM


4. DUCTWORK INSULATION K.m2/W

ft2F.h/Btu

For example, if the interior of your home is at 20 °C, and the roof cavity is at 10 °C, the temperature difference is 10 K. Assuming a ceiling insulated to R–2, energy will be lost at a rate of 10 K / 2 K·m²/W = 5 watts for every square meter of ceiling.

The R value

is the reciprocal of U-value(α)


56



3. VINADUCT SYSTEM


4. DUCTWORK INSULATION Fibrous glass

Aeroflex Thermobreak Polyurethane Foam

FIBERGLASS

IMPROVES

THE

IE

Temperature control

Acoustical control

Energy conservation

Condensation control

Mold and fungus resistance

Fire safety

Durability and integrity

Proven performance

57

SHEET METAL DUCTS WITH FIBROUS GLASS INSULATION LINER

58

SHEET METAL DUCTS WITH FIBROUS GLASS INSULATION WRAP

59

SHEET METAL DUCTS WITH FIBROUS GLASS INSULATION BOARDS

60

BÔNG THỦY TINH Công Ty TNHH Cách Nhiệt Phương Nam

TỶ TRỌNG(Kg/m3)

ĐỘ DÀY(mm)

KHỔ RỘNG(m)

CHIỂU DÀI(m)

HỆ SỐ R(m2K/W)

10 50 1,2 15 / 30 1,05

12 50 1,2 15 / 30 1,17

16 50 1,2 15 1,24

24 50 1,2 12 1,33

32 50 1,2 10 1,45

10 100 1,2 12 2,10

12 100 1,2 10 2,24

16 100 1,2 10 2,48


61

DRAWBACK OF FIBERGLASS

When ducts experience condensation, moisture collects in

the fiberglass, causing it to pack and lose its insulating value

During the wrapping process of installation, the fiberglass is

pulled tight around corners causing packing which interferes

with the ability of the fiberglass to achieve full insulating

R-value

Fiberglass must be carefully installed and kept dry to reach

and maintain its stated R-value

Has no effect on radiant heat transfer



3. VINADUCT SYSTEM



Aeroflex Thermobreak Polyurethane Foam


62

AEROFLEX

Moisture resistance

Thermal efficiency

Flame and smoke proof

Anti vibrations and Resonance

Neat appearance

can be safely handled without causing skin irritation and health hazards



3. VINADUCT SYSTEM



Aeroflex

Thermobreak Polyurethane Foam


63

AEROFLEX

Ambient Condition

Operating Temperature

60 °F (15.5 °C) 55 °F (12.7 °C) 50 °F (10 °C) 45 °F (7.2 °C)

80 °F (26.6 °C) 50% RH

1/4" (6 mm.) 1/4" (6 mm.) 1/4" (6 mm.) 3/8" (9 mm.)

85 °F (29.4 °C) 70% RH

3/8" (9 mm.) 3/8" (9 mm.) 3/8" (9 mm.) 1/2" (12 mm.)

90 °F (32.2 °C) 80% RH

5/8" (15 mm.) 3/4" (19 mm.) 3/4" (19 mm.) 1" (25 mm.)

90 °F (32.2 °C) 85% RH

1" (25 mm.) 1" (25 mm.) 1" (25 mm.) 1-1/4" (32 mm.)

Thickness Recommendation for Ducting System



3. VINADUCT SYSTEM



Aeroflex

Thermobreak Polyurethane Foam

CK05BNH

64

AIR DUCT SYSTEM

Bảo tàng Hồ Chí MinhTòa nhà Sill Tower


65

THERMOBREAK1. DUCT CONSTRUCTION MATERIALS


3. VINADUCT SYSTEM


4. DUCTWORK INSULATION Fibrous glass Aeroflex

Thermobreak

Polyurethane Foam


66



3. VINADUCT SYSTEM



Thermobreak

Polyurethane Foam


67

THERMALBREAK1. DUCT CONSTRUCTION MATERIALS


3. VINADUCT SYSTEM



Thermobreak

Polyurethane Foam


68



3. VINADUCT SYSTEM



Thermobreak

Polyurethane Foam


69

Polyurethane Foam Insulation1. DUCT CONSTRUCTION MATERIALS


3. VINADUCT SYSTEM


4. DUCTWORK INSULATION Fibrous glass Aeroflex Thermobreak

Polyurethane Foam


70

Advantages

Block airflow by expanding and sealing off leaks, gaps.

Provides acoustical insulation (like loose-fill, but superior).

Cementitious Foam is fireproof

Can serve as a vapor barrier with a better permeability

rating than plastic sheeting vapor barriers and consequently

reduce the build up of moisture.

Can be applied in small quantities.



3. VINADUCT SYSTEM



Polyurethane Foam


71

Disadvantages

The cost can be high compared to traditional insulation.

Can shrink slightly while curing if not applied on a substrate

heated to manufacturer's recommended temperature.

Contain hazardous chemicals such as benzene and toluene.

These are a potential hazard and environmental concern during

raw material production, transport, manufacture, and installation.

Many foam insulations are made from petrochemicals and

may be a concern for those seeking to reduce the use of fossil

fuels and oil. However, some foams are becoming available that

are made from renewable or recycled sources.

R-value will diminish slightly with age. Even after this process,

the stabilized R-value is very high.



3. VINADUCT SYSTEM



Polyurethane Foam


72



3. VINADUCT SYSTEM

4. AIRDUCT INSULATION


1. Install duct fully extended; do not install in the compressed state or use excess lengths. This will noticeably decrease friction losses.

2. Avoid bending ducts across sharp corners or incidental contact with metal fixtures, pipes or conduits. Radius at center line should not be less than one duct diameter.

NOTES IN INSTALLATION


73



3. VINADUCT SYSTEM



3. Do not install near hot equipment (e.g., furnaces, boilers, steam pipes, etc.) that is above the recommended flexible duct use temperature. 4. Do not use for vertical risers in air ducts systems serving more than two floors. 5. Avoid installations where exposure to direct or indirect sunlight or UV producing air treatment devices can occur. Prolonged exposure to sunlight or UV light may cause degradation of the core material or the vapor barrier. 6. Should not be installed within 4 inches (101.6 mm) of hot equipment (furnaces, boilers, steam pipes, etc.) that is above 250o F (121o C). 7. Should not penetrate walls where fire dampers are required. 8. Should not be installed in concrete, buried below grade or in contact with the ground.

SUPPORTING FLEXIBLE DUCT


74



3. VINADUCT SYSTEM




1. Flexible duct shall be supported at manufacturer’s recommended intervals, but at no greater distance than 5 feet (1524 mm). Maximum permissible sag is ½ inch per foot of spacing between supports.

2. Hanger or saddle material in contact with the flexible duct should be of sufficient width (minimum 1 ½” (38 mm)) to prevent any restriction of the internal diameter of the duct when the weight of the supported section rests on the hanger. Individual ducts should be separately supported.


75



3. VINADUCT SYSTEM




3. Flexible ducts may rest on ceiling joists or truss supports. Maximum spacing between supports should not exceed the maximum spacing per manufacturer’s installation instructions.

4. Support the duct between a metal connection and a bend by allowing the duct to extend straight for a few inches before making the bend.


76



3. VINADUCT SYSTEM




5. Vertically installed duct should be stabilized by support straps at a maximum of 6 feet (1829 mm) on center.


77

REFERENCES

1. HVAC SYSTEM DUCT DESIGN – SMACNA – FOURTH EDITION 5/20062. VINADUCT FITTING CATALOG 2007.3. SPECIFICATION FOR SHEET METAL DUCTWORK – HVCA.4. SPECIFICATION FOR PLASTICS DUCTWORK – HVCA.5. WEBSITE:www.ductwork.com www.kbduct.comwww.hvacr.vnwww.aeroflex.comwww.foaminsulation.netwww.cachnhiet.com.vn

http://www.ductwork.com/

http://www.kbduct.com/

http://www.hvacr.vn/

http://www.aeroflex.com/

http://www.foaminsulation.net/

http://www.cachnhiet.com.vn/

Documents

AIR DUCT