2. Fundamentals of insulation
Fundamentals of insulation
Kuwait, February 2012
Product Manager Insulation ‐ ME, India & Africa
Product Manager Insulation ‐ ME, India & Africa
Dr. Laurenţiu Pestriţu MBE
Dr. Laurenţiu Pestriţu, MBE
Laurenţiu Pestriţu,

3. PROGRAM
17:00 ‐
17:00 ‐ 17:30
 The insulation
 Why should we insulate?
y
 Aerofoam NBR insulation
 Aerofoam XLPE insulation
February 2012,
February 2012,
Kuwait

4. THE INSULATION Definition
Insulation – a material that reduces or
prevents the transmission of heat or sound or
electricity
February 2012,
February 2012,
Kuwait

5. THE INSULATION Classification
INSULATING MATERIALS
Open cell:
Open cell: Closed cell:
Closed cell:
 Rockwool  polyurethane
p y
 mineral wool  polystyrene
 glass wool
g  glass
g
 cork  polyethylene
 (polyurethane)
(p y )  elastomeric
 (polystyrene)
February 2012,
February 2012,
Kuwait

6. WHY INSULATE? Scope
Refrigeration and AC
Refrigeration and
Refrigeration and AC
Targets:
Targets:
1. Condensation control
. Condensation control
2. Minimizing thermal loss
. Minimizing thermal loss
Minimizing thermal loss
Heating
Target:
Target: ‐ minimizing thermal loss
February 2012,
February 2012,
Kuwait

7. WHY INSULATE? Selection criteria
Temperature Thermal conductivity
of the agent ( )
Vapor barrier ()
Vapor barrier (
Ease of installation
Ease of installation Fire resistence
Fire resistence
(flexible insulation) ‐ Class O ‐
Class O ‐
February 2012,
February 2012,
Kuwait

8. WHY INSULATE? Thermal
conductivity
 0,024 Air
 0,034
0 034 Cross linked PE
Cross linked PE
 0,035 Elastomeric insulaton
 0,200 Wood
 0,550
0 550 Water
W
 0,840 Concrete
λ‐value
0.9
0.8
0.7
07
0.6
0.5
0.4
0.3
0.2
0.1
0
Air Aerofoam Aerofoam
Aerofoam Aerofoam Wood Water Concrete
XPE NBR
February 2012,
February 2012,
Kuwait

9. WHY INSULATE? Theory ‐
Theory ‐
condensation
Refrigeration and AC
Refrigeration and AC
Targets:
Targets:
1. Condensation control
. Condensation control
2. Minimizing thermal loss
. Minimizing thermal loss
Minimizing thermal loss
February 2012,
February 2012,
Kuwait

10. INSULATION Theory ‐
Theory ‐
condensation
For HVAC scopes
F HVAC
Can be used only closed‐cell insulation materials:
February 2012,
February 2012,
Kuwait

11. INSULATION Important
aspects
Top 5 important aspects regarding
Top 5 important aspects regarding
closed cell insulation
l d ll i l ti
1) Strong water vapor resistance factor ‐ 
2) Low thermal conductivity
2) Low thermal conductivity – λ
3) Use of right insulation thickness
4) Correct installation – tightness of the glued joints
5) Keeping the minimum distance among insulated objects
) h d l d b
February 2012,
February 2012,
Kuwait

12. INSULATION Important
aspects
λ
µ
Heat flow (λ) and diffusion flow (µ) are caused by the
difference in the line and ambient temperatures
February 2012,
February 2012,
Kuwait

13. INSULATION . 
1.  value
1. STRONG WATER VAPOR BARRIER
. STRONG WATER VAPOR BARRIER
Water vapor diffusion resistance factor ‐ 
Water vapor diffusion resistance factor ‐
  7000
February 2012,
February 2012,
Kuwait

14. INSULATION . 
1.  value
Tline + 6°C
RH 0%
There is pressure difference of
water vapor between ambient
air and closed cell structure of
insulation (due to temperature
difference between the line and the
ambient).
The pressure difference is
creating a diffusion flow which
is forcing the ambient water
vapors into the insulation
(towards lower temperature).
Tamb +
+
22°C
February 2012,
February 2012,
Kuwait RH 70%

15. INSULATION . 
1.  value
Tline + 6°C
RH 0%
For poor quality materials
(with low  value) insulation
will get wet.
ill
Therefore one should apply
high quality insulation
materials (i.e. with high value
of water vapour diffusion
resistance factor )
Tamb +
+
22°C
February 2012,
February 2012,
Kuwait RH 70%

16. INSULATION . 
1.  value
Tline + 6°C
RH 0%
Thanks to strong  value water
vapor penetration is very slow
and kept at limited level.
p
 > 7000
Tamb +
+
22°C
February 2012,
February 2012,
Kuwait RH 70%

17. INSULATION . 
1.  value
THE DIFFERENCE BETWEEN HIGH AND LOW 
THE DIFFERENCE BETWEEN HIGH AND LOW 
 < 7000   7000
Vapors diffusion
Vapors diffusion
February 2012,
February 2012,
Kuwait

18. INSULATION 2. λ value
. λ value
2. LOW THERMAL CONDUCTIVITY
. LOW THERMAL CONDUCTIVITY
 ≤ 0,035
Low 
Low quality materials
Low quality materials
High 

High quality materials
High quality materials
10 yrs
10
February 2012,
February 2012,
Kuwait

19. INSULATION 3. Insulation
. I
thickness
3. USING THE CORRECT INSULATION THICKNESS
. USING THE CORRECT INSULATION THICKNESS
Depending on the pipe diameter
the minimum insulation thickness
should be calculated (other
influencing parameters are: ambient
are:
temperature,line temperature, relative
humidity, surface coefficient, thermal
conductivity)
Φ 114 mm
Thickness: 19 mm
Diameter: 15 mm
Thickness: 24,5 mm
Diameter: 114 mm
February 2012,
February 2012,
Kuwait

20. INSULATION 3. Insulation
. I
thickness
The influence of pipe diameter size towards the
heat flow (and towards the insulation thickness)
Plain surface Curved surface
A1 A1 A1
0 0
0
A2 A2 A2
A bigger insulation thickness is required for pipes with
bigger diameters
February 2012,
February 2012,
Kuwait

21. INSULATION 4. Correct
. Correct
installation
4. TIGHTNESS OF INSULATION GLUING
. TIGHTNESS OF INSULATION GLUING
Installation must be done with products which assure a good
Installation m st be done ith prod cts hich ass re a good
gluing at the joints and on the entire length of the pipe.
Tline 6°C
RH 0%
RH 0
RH
Rigid insulation
Ri id i l i may oftenf
contain spaces (due to
wrong cutting) where
condensation can appear.
appear.
February 2012,
February 2012,
Kuwait

22. INSULATION 4. Correct
. Correct
installation
Tight joints
The system integrity (tight joints) is assured by following a right
installation procedure and by using the right adhesive.
The adhesive glues the insulation surfaces through a chemical
reaction which has as result the “cold vulcanization”.
“cold vulcanization”
g
guarantees the
required tightness
February 2012,
February 2012,
Kuwait

23. INSULATION 5. Surface
. Surface
coefficient (h)
5. KEEPING THE MINIMUM DISTANCE
. KEEPING THE MINIMUM DISTANCE
AMONG INSULATED OBJECTS
hr
h = hr + hcv
h
hcv = convective
contribution of
t ib ti f
surface coefficient
hr = radiative
contribution of
hcv
surface coefficient
February 2012,
February 2012,
Kuwait

24. INSULATION 5. Surface
. Surface
coefficient (h)
Aerofoam
Aerofoam
with steel (flat /
painted Aerofoam
mat) cladding
with alu
h l
(silver)
cladding
Aerofoam
A f
not painted
 10 W
m2 . K 8 W
 5,7 W
February 2012,
February 2012,
m2 . K m2 . K
Kuwait

25. INSULATION 5. Surface
. Surface
coefficient (h)
Surface coefficient h
Without
With steel With alu
cladding /
Cladding (flat / mat)
(flat / mat) (silver)
(silver) Static area
Static area
insulation
cladding cladding
painted
3
Value of
surface
coeff. h
[W/m2K]
10 8 5,7
,
Insulation
Insulation
thickness
s)
( 0
so 1,5 * so 1,9 * so  3,0 * so
February 2012,
February 2012,
Kuwait

26. INSULATION 5. Surface
. Surface
coefficient (h)
Higher probability of forming condensation
in the static areas
Lack of air flow (convection)
February 2012,
February 2012,
Kuwait

27. INSULATION 5. Surface
. Surface
coefficient (h)
Recommended distances among the insulated objects
 for small objects: 100 mm
100 mm
 for big objects: 1000 mm
1000 mm

100 mm    
100 mm
100 mm 100 mm
100 mm 100 mm
100 mm 100 mm
100 mm

100 mm

1000 mm  
1000 mm 1000 mm
February 2012,
February 2012,
Kuwait

28. INSULATION 5. Surface
. Surface
coefficient (h)
Especially important for chilled water pipe works
Pipe works in
office and hotel
buildings
February 2012,
February 2012,
Kuwait

29. INSULATION 5. Surface
. Surface
coefficient (h)
Effects of not keeping the right distance among the
insulated objects
Condensation
February 2012,
February 2012,
Kuwait

30. THE INSULATION Classification
INSULATING MATERIALS
Open cell:
Open cell: Closed cell:
Closed cell:
 Rockwool  polyurethane
p y
 mineral wool  polystyrene
 glass wool
g  glass
g
 cork  polyethylene
 (polyurethane)
(p y )  elastomeric
 (polystyrene)
February 2012,
February 2012,
Kuwait

31. INSULATION Features
Cross linked PE at a glance…
Cross linked PE at a glance…
Almost zero water vapour permeability and water
absorption – vapour water barrier as per ASHRAE and British
Standards
Passed a wide range of fire and smoke tests for building
materials
t i l
Passed toxicity levels of combustion gases as per
ISO5659 IMO Resolution MSC61
Safe, fast and easy installation ‐ integrated material
February 2012,
February 2012,
Kuwait

32. INSULATION Features
No loose fibres that may cause irritations both on
installation and service
Environmentally friendly:
‐ CFC and HCFC free
‐ does not contain nor use in its production substances
that contribute to Ozone Depletion Potential (ODP) and
Global Warming Potential (GWP)
February 2012,
February 2012,
Kuwait

33. INSULATION Applications
Application types
Square ducts Round ducts Walls
Pipes Storage tanks Raised floors
February 2012,
February 2012,
Kuwait

34. INSULATION Properties
Vital Insulation Properties
1. Thermal Conductivity – defines the thermal performance of
y p
the material
The lower the value, the better the thermal performance.
Varies according to mean temperature.
Varies according to mean temperature.
Symbol: λ, Units: W/mK, Standard: ASTM C518
2.
2 Water Vapour Permeability – the diffusion of water vapors
into the insulation
The more permissive is the material , the higher the thermal conductivity
will become over time
time.
Varies with temperature and relative humidity.
Unit: g/h.m2, Standard: ASTM E96
3. Water Absorption – amount of water a material can absorb
More water absorbed means lower thermal performance of the material
over time.
ti
Varies with density of the material.
February 2012,
February 2012,
Kuwait
Standard: BS EN 12087

35. INSULATION Water absorption
Water Absorption
Cross linked PE: 0
Cross linked PE: 0.3% Mineral Fiber: 100%
Mineral Fiber: 100%
Water absorption
Water absorption
(% by volume)
100
90
80
70
60
50
40
30
20
10
0
February 2012,
February 2012,
Kuwait

36. INSULATION Comparative
performance
Comparison of insulation performance
Fibreglass NBR XLPE
Resin bonded Extruded PVC Crossed‐linked
Name
N
glass fibers Nitrile Rubber polyethylene foam
Type of material Open cell Closed cell Closed cell
Thermal conductivity [W/mK]
Thermal conductivity [W/mK] 0.036 0.038
0 036‐0 038 0.035
0 035 0.034
0 034
Water vapour permeability 75 perm‐in 0.02 perm‐in 0.00 perm‐in
Condensation control No Yes Partial
Integrated product
Integrated product No Partial Yes
Fibre free product No Yes Yes
Reliability in time Low High High
Ease of installation
Environmentally friendly
February 2012,
February 2012,
Kuwait

37. INSULATION Comparative
costing
Comparison of installation costs
Condition: Indoor installation of AC ducts
Estimate for
Item
10,000m2 duct
S/N XLPE (13mm) FIBERGLASS (25mm) ELASTOMERIC (13mm)
Description
work
Insulation
1 10,000 m2 18 180,000.00 6.5 65,000.00 14 140,000.00
Material
2 Adhesive Glue 3,000 liters NIL 0.00 10 30,000.00 10 30,000.00
(4 US
3 1st coat foster 608 NIL 0.00 60 36,480.00 0 0.00
Gallons)
4 canvas cloth 1,186 rolls NIL 0.00 15 17,790.00 0 0.00
(4 US
5 2nd coat foster 660 NIL 0.00 100 66,000.00 0 0.00
Gallons)
labor and
6 1,000 manhours 5.5 5,500.00 16 16,000.00 5.5 5,500.00
fabrication
Total Cost of Labor and Materials AED 185,500.00 AED 231,270.00 AED 175,500.00
Cost savings compared to fiberglass 19.79% 24.11%
February 2012,
February 2012,
Kuwait

38. INSULATION Comparative
performance
Comparison of insulation performance
Condition: Installation of AC ducts in conditioned areas
Internal External %
Insulation Thermal Heat
Surface Surface Tline Tamb ∆T Reduction
Thickness
Thi k Conductivity
C d ti it Flow Q
Fl
Insulation Material Coefficient Coefficient of Heat
(°C) (°C) (°C) 2
L (mm) λ (W/mK) (W/m K)
fi fo Flow
XLPE 13 22 5.7
57 0.034
0 034 9 30 21 34.81
34 81 79%
NBR 13 22 10 0.036 9 30 21 41.46 75%
Fiberglass 17.5 22 10 0.037 12 25 13 21.021 72%
Assuming at least 30% compression of fibreglass
l ffb l
As per BS5422:
ΔT
fi internal surface coefficient Q = 1/f + L/λ + 1/f
fo external surface coefficient i o
Galvanized sheet metal 8 W/m2K
February 2012,
February 2012, Bright reflective surface 5.7 W/m2K
Kuwait White painted surface 10 W/m2K

39. Questions?