new technical bulletin flexible duct - caryaire duct.pdf · uninsulated duct insulated duct...
TRANSCRIPT
CARYAIRE FLEXIBLE DUCT is strong, fully flexible light weight duct which is widely used in air conditioning and
ventilation systems for commercial, industrial and residential application
CARYAIRE FLEXIBLE DUCT is extremely durable and will maintain dimensional stability when fully extended. It is
highly efficient when correctly installed & produces a maintenance - free service life under normal operating
conditions.
I N F O R M A T I O NP R O D U C T
/ Tear and puncture resistant construction.
/ Smooth inner core, with minimum friction losses.
/ Highly resistant to corrosion and micro organisms.
/ Light weight compressed ducts reduces freight and storage costs.
/ No Air leakage - Energy efficient.
/ Spring steel wire ensures dimensional stability & resists mechanical abuse.
/ Speedy completion of project
/ Offers a high degree of flexibility, which allows it to be easily connected to any desired position.
/ A quick and economical means of correcting misalignment between system components.
/ Allows ducting around obstacles where fabricated and fitted ducts would be difficult and costly to install.
SALIENT FEATURES APPLICATIONS AND BENEFITS
FLEXIBLE DUCT INSULATED FLEXIBLE DUCT
F e b . 2 0 0 6
F L E X I B L E D U C T
CARYA I RE TM
Total Climate and Air Management Company
UNINSULATED DUCT
INSULATED DUCT
CARYAIRE insulated flexible duct is made of a double lamination of films permanently bonded to a coated
spring steel wire helix. Thermal efficiency is provided by wrapping the exterior with a blanket of fiberglass
insulation. The outer jacket is made of double laminated film which acts as a vapour barrier surface as well.
Standard Length : 25 ft.
Range : 150mm to 450mm dia.
Max. Permissible Velocity : 5000 fpm
Max Recommended Working Pressure : 8" w.g.
Puncture Test : Complies wire UL - 181 part 14
Temperature Range : 32 - 200° F
Insulation Thickness : 1.25 inch
3Insulation Density : 14 kg/ m
2Insulation R - Value : 4.2 (°F - Ft - hr/Btu)
Packing : 1 pc (25 ft) per carton
CARYAIRE uninsulated flexible duct is made of a double lamination of films permanently bonded to a coated
spring steel wire helix.
Standard Length : 25 ft.
Range : 150mm to 500mm dia.
Max. Permissible Velocity : 5000 fpm
Max. Recommended operating pressure : 6" w. g. positive all dia.
: ½" w.g. negative all dia.
Packing : 1 pc (25ft) per carton
Material of Construction
Uninsulated Duct & Inner Core
for Insulated Duct
FD1 - Metalised Polyester Film on
Inside & Outside
FD2 - Aluminum Film on Outer Side &
Metalised Polyester Film on
Inner Side.
FD3 - Aluminum Film on Inside &
Outside
Duct Size (mm)
150
200
250
350
400
450
500
Material of Construction
Outer Sleeve (For Insulated
Flexible Duct)
Type A - Metalised Polyester Film on
Inside & Outside
Type B - Aluminum Film on Outer Side
& Metalised Polyester Film on
Inner Side.
Type C - Aluminum Film on Inside &
Outside
ORDERING INSTRUCTION
X X X X X X X
2. Bending Radius
All bends should be made as large as possible and should have a radius of not less than the diameter of the duct in use. This reduces un-favourable pressure losses and is particularly important for metal based products which are more susceptible to stress rupturing. Double bends should be avoided, however if un-avoidable, ensure that each radius is not less than R = 2 x D
3. Straps
Ideally the hanging straps should support the flexible duct with a minimum of half the circumference surface in contact, and without reducing the effective inside diameter of the duct. It is also recommended that the minimum width of material to be used for the hanging straps should be at least 25 mm.
R
D
DD
1xD 1xD
4. Flexible Duct to Conventional Duct Connection
Extra care should be taken when making flexible connection to fixed conventional ducts, etc., and ensure that they do not become too stressed. An additional support is recommended to obviate this potential problem.
Metal based flexible duct products are particularly prone to fracturing due to stress caused as a result of sharp connections.
Connections to ceiling illumination "troffer boxes" should be served in the most direct manner similar to that described for conventional ducts.
Too many bends, when connecting to "troffer boxes" and/ or any other type of air supplying component, may result in excessive pressure loss and the generation of noise.
Figure-A Illustrates a poor connection arrangement, and figure-B shows the correct manner.
5. Longer Length installation
In the event where extreme length of flexible duct is to be installed, round duct connectors made of galvanised sheets of at least 30 cm long should be used to connect the duct at every distance of 10 meters. Use metal or galvanised hangers as recommended (point 3) to support the point where connections are made. Light railings is a good alternative hanging support when using long length of flexible duct.
Figure-A Figure-B
Not Recommended Recommended
6. Direct Contact
It should be emphasized that the flexible duct must not be in direct physical contact with un-insulated heating or hot process pipes. If in the event where such situation cannot be avoided, additional 1" thick insulation should be wrapped around pipes that are in contact with the duct.
25mm
25mm
Position of extra stressingCausing material rupturing
Not Recommended
Recommended
Maximum sag allowable 50 mm per meter
The flexible duct must be installed fully extended to produce optimum results.
The maximum allowable sag, between any two adjacent suspension points, should not exceed 50 mm per meter
The distance between any two adjacent suspension points may vary from 1.50 to 3.00 meter, depending upon the type of flexible duct in use.
Flexible ducts mounted above suspended ceilings should always be independently supported. Ducts mounted in these locations are susceptible to damage whenever ceilings panels need to be periodically interchanged, unless they are separately supported.
1. Support Hangers
RECOMMENDED INSTALLATION PRACTICES
FLEXIBLE DUCT - FRICTION LOSS DIAGRAM
The scope of this section comprise supply, installation testing & commissioning of flexible ducting conforming to these specification & in accordance with
requirements of drawings & schedule of quantities.
Wherever specified, uninsulated flexible duct shall be made of double lamination of Metalized Polyester film permanently bonded to a coated spring steel
wire helix. Duct shall be in tear & puncture resistant construction.
Wherever Insulated Flexible Duct are specified inner core for the same should be made of double lamination of Metalized Polyester Film permanently 2
bonded to a coated spring steel wire helix. Fiberglass insulation of minimum 14 kg/cu. meter density, having R-Value 4.2 °F - Ft - hr/Btu & 1 inch
thickness shall be wrapped over the inner core & covered with strong outer jacket cum vapour barrier made of fibreglass reinforced Metalized polyester
film laminate.
Care must be taken to install all the flexible duct in fully extended position & bends made with adequate radius as per manufacturer recommended
practices.
GUIDE SPECIFICATIONS
200
100
50
40
30
20
10
7
5
3
2
1
20010050 500 1000 2000 5000 10000
150
020
250
300
350
400
450
500
PR
ES
SU
RE
LO
SS
in P
a/m
3AIR FLOW VOLUME in m / hr
CT
DA
TR
Sm
DU
I
ME
E (
m)
24
02
18
16
14
10
9
7
8
6
5
4
3
Ar el
tm
sec)
i Voci y (
/
Caryaire Equipments India Pvt. Ltd.Head Office : NOIDA
MUMBAI
BANGALORE
USA
Caryaire Equipments India Pvt. Ltd.Head Office : A-10, Sector-59, NOIDA - 201 301 U.P. (India) Tel.: + 91 120 2580553, 54, 55, 56 Fax : + 91 120 2580557
E-mail : [email protected] / [email protected] WEBSITE : http://www.caryaire.com
Export Division : Tel. : +91-120-2589092 Fax : +91-120-2589093 E-mail : [email protected]
MUMBAI Tel. : +91 22 55702056, 55702057 Fax : +91 22 28547314 E-mail : [email protected]
BANGALORE Tel. : +91 80 25727830, 31 Fax : +91 80 25727833 E-mail : [email protected]
USA Tel. : 001 704 594 6984 Fax : 001 704 548 1528 E-mail : [email protected]
Export Division :
CARYA I RE TM
Total Climate and Air Management Company