TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Non-Metallic Duct Board
U.P.Twiga Fiberglass Ltd.
AIC Tech
14th Sep.2013
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Purpose of A HVAC Duct
• To carry conditioned air from AHU to conditioned place without gaining much temperature/loosing energy.
• To deliver noise free air.
• To maintain quantity (flow rate) and quality of conditioned air:
-Minimum leakage,
-Minimum frictional loss,
- Minimum pressure loss
- No contamination
All these above parameter can be met with Metallic and Non
metallic HVAC ducts subjected to proper installation.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
How non metallic duct helps better
• High level of thermal and acoustic insulation according to required standards what conventional systems with lower thickness of insulation cannot achieve.
• Minimize leakage rate (< 1%, 80% better than Metal duct) hence provide better energy conservation.
• Duct fabrication and insulation in one single operation.
• Speedy execution with minimum wastage.
• Small modifications can be accommodated in fast and effective manner.
Non Metallic insulated duct system is technologically more
advanced and provide efficient ducting envelope in comparison
to conventional metal ducting system.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Agenda
• Non metallic duct
• Product Features
• Application Features
• Performance
• Summary
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Non metallic duct
• Long insulation boards (typically 3 m) converted to rectangular ducts with the help of specially designed tools. Insulation material –either High density Glass wool or Plastic foams suitably laminated with multilayer facings on both faces.
• Outer face is tough/reinforced and inner face is without reinforcement, designed to have grooving operation easily.
• Straight Duct modules can be joined through male-female edges to make longer ducts.
• External faces are cut/joined differently to produce Elbow, Offset, reducer.
• One or more elbow, straight ducts etc are cut and joined accordingly to produce- r-joint, triple-joint, and other complicated duct network.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Product Features: Duct joints
• Ship-lap joint to join two straight duct module.
• Perfect sealing
• Least leakage rate
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Product Features-Laminations
• Integrated Lamination options. Sometimes multicolor options.
• External side-Aluminum foil/ decorative laminations
• Internal side-Aluminum or Black glass cloth Textile
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Application Feature-Straight Duct Method
(SDM)
• Single piece ducting- only one joint length wise.
• Multiple pieces for higher dimension duct. (external perimeter>3m).
• Wastage reduction is done by joining cut pieces from duct boards to make complete duct.
Redpoint
Redpoint
Redpoint
Bluepoint
Bluepoint
Red point
Blue point tool to cut chair-shape joints and leave a flap for duct closure.
Red point tool to cut chair-shape joints in order to foldduct boards to 90`.
Black point tool to cutshiplaps for flat piecesfabrication.
A
A
A A
A A
AA
B
B
Two pieces in -L- duct
-U- single piece andflat piece duct
Single pieceduct
Four piecesduct
B
B
B
B
B
B
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Application Feature- Sealing
• Stapling and Taping in Straight duct module and joining of two modules together.
• Adhesive and Taping for Elbow, Offset
• All joints are inspected from inside.
• Curing time need to be provided before going for test/operation.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Application Feature- Straight duct to Other
shapes
• External guidelines to help proper cutting at 22.5o
• No/minimum wastage
• Elbow, Offset, r-joint, triple joint, double offset etc.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Application Feature-Reinforcement, metal
profiles, fittings
• H-profile to join grill/diffuser.
• All sort of metallic air supply components can be fitted with non metallic ducts with the help of profiles.
• Reinforcement for bigger sized ducts at certain pitch.
2
3
41.- CLIMAVER duct2.- U-shaped profile3. Sheet metal screws4.- Metal plate
1
CLIMAVER
CLIMAVER
CLIM
VER
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Network with Non metallic ducts
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Performance
• Thermal
• Acoustic
• Fire
• Stiffness and Pressure
• Pressure Loss and Leakage
• Limitations
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Thermal Performance
• Thermal Conductivity <=0.032 W/m.K
• Thermal Resistance(25mm)
>= 0.75 sq.m.K/W
• ECBC/ASHRAE compliant.
• 6-19 mm thick insulation does not comply ECBC. Non metallic ducts have 41 % more thermal resistance.
• Insulation efficiency (U-value improvement) of non metallic ducts : 28% w.r.t 19mm thick insulated metal ducts
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Acoustic Performance
ACOUSTICAL ABSORPTION (dB/ m)
Duct 400 x 500 mm
Frequency (Hz)
125 250 500 1.000 2.000 4.000
Metal duct – no insulation /Foam duct 0.07 0.07 0.19 0.19 0.1 0.07
Metal duct – External insulation 50 mm 0.14 0.14 0.38 0.38 0.2 0.14
Non metallic fiberglass duct with
aluminum lining1.26 1.26 1.26 4.99 3.97 3.01
Non metallic fiberglass duct with textile
lining1.67 4.99 5.52 8.86 9.45 8.86
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Fire Performance( glass wool ducts)
• Ducts made of inorganic glass fiber insulation is incombustible in nature.
• Minimum/Zero smoke emission.
• No incandescent droplets.
• Complies/Supersede International Mechanical Code- limited spread of fire/ flame/toxic fumes.
• Unlike rubber/polyethylene based external insulation it is completely safe at core and least potential to fire hazard.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Stiffness and Pressure
• Stiffness:
Class R5 according to EN-13403 (MAXIMUM LEVEL)
Tested in accordance with EN-13403
• Pressure:
Ductboards can stand pressure up to 800 Pa with no evidence of breaks(Tested at 2000 Pa, derated by 2.5)
Tested in accordance with EN-13403
Classification for board stiffness
Stiffness class Flexural rigidity [EI] N
mm2
R 1 55,000
R 2 90,000
R 3 160,000
R 4 200,000
R 5 300,000
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Pressure Drops and Leakage
• Similar to Metal ducts owing to its aluminum facing based surface backed with rigid and flat insulation boards . ASHRAE charts for metal ducts can be consultant pressure drop.
• Leakage rate is quite low than metal ducts( less than 1%, best/D category) owing to its ship lap joints – tight fit and more area contact. (Ref: Test report extract).
• Conventional Metal ducts have approx. 5% leakage rate.
PRESSURE DROPS IN CURVED ELBOWS AND IN
THREE-PIECE DUCT ELBOWS
0
10
20
30
40
0 1.75 3.5 5.25 7 8.75 10.5 12.25 14
Speed in m/ s
Pre
ssu
re d
rop
in m
m c
.a.
Curved
Elbow
300x300
Three-
pieces Duct
300x300
Curved
Elbow
390x320
Three-
pieces Duct
390x320
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Erosion/Particle Migration(IAQ requirement)
18 m/s for 5 Hr.
0.022µgm/cu.m against maximum
limit of 60µgm/cu.m
EN 13403 / UL
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Limitations
• Smoke or gasses evacuation.
• Outside placed ducts, or buried, without protection.
• Vertical ducts 3 m without reinforcements
• USE LIMITS
- Static pressure >800 Pa (80 mm c.a.)
- Air speed > 18 m/s
- Internal air temperature > 90ºC
- External air temperature > 65ºC
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Summary
Parameter Non Metallic-
Glass Wool
ducts
Non Metallic-
Foam Ducts
Metallic Ducts+
19mm Insulation
Thermal
Resistance
High (ECBC
compliant)
High (ECBC
compliant)
Low (Non
compliant)
Acoustic
Parameter
High absorption Low absorption Low absorption
Frictional Loss of
Pressure
Meets ASHRAE
requirement
At bends/Elbow
slightly better than
metal duct
Same as Metal
duct
Meets ASHRAE
requirement
Leakage Rate <1% 3-4% 5%
Maximum
Pressure
800 Pa ( Test at
2000 Pa)
Same Suitable for
Higher pressure
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Summary, cont.
Parameter Non Metallic-
Glass Wool
ducts
Non Metallic-
Foam Ducts
Metallic Ducts+
19mm Insulation
Fire Parameter Best in class. Non
combustible at
core. No
incandescent
droplets
Plastic foam is
combustible in
nature. Fire
droplets possible.
PIR ducts are
comparative
better than PUF
Combustible with
plastic/rubber
based insulation.
Fire safe with
Glass wool
insulation
Stiffness/Rigidity Meets Highest
class (R5)as per
EN std.
Rigid Highest rigidity,
better than non
metallic ducts
Erosion Zero erosion Zero Erosion Depends on
proper installation
of acoustic lining.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Summary, cont.
Parameter Non Metallic-
Glass Wool
ducts
Non Metallic-
Foam Ducts
Metallic Ducts+
19mm Insulation
Application Need better
skilled applicators
Need better
skilled applicators
Factory made
ducts. Installation,
insulation
application does
not need mush
skilled applicators
Ease of operation Duct making and insulation in a single
operation at much faster speed and
less number of persons
Two different
operation with
different set of
applicators. Noisy
and jobs need
much more
manual labor.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Summary, cont.
Parameter Non Metallic-
Glass Wool
ducts
Non Metallic-
Foam Ducts
Metallic Ducts+
19mm Insulation
Adaptability at site High, minor changes can be
accommodated with minimum
resource.
Low, difficult to
modify once duct
is fabricated.
Cost Competitive. Low cost for
transportation. Indirect cost saving-like
installation/labor cost, speedy
execution etc.
Similar to Non
metallic duct.
Suitability/
Limitation
Upto 800 Pa and 18 m/s , Not for
buried and external ducts.
No limitation for
pressure or
velocity. Used as
Buried and
external ducts.
TWIGA
IMO certified by-
SAINT GOBAIN
A Technical Licensee of-
Q&A