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8 HARDNESS

PENETRATION

60 60 IT IS MECHANICAL PROPERT

TO RESIST PENETRATION

9 HYGOSCOPICIT %

VOLUME

10-15 10-15 ABILITY TO ABSORB AND

RETAIN WATER

10 RESISTANCE TO ACIDS GOOD

EXCEPT

HF

H3PO4

GOOD

EXCEPT

HF

H3PO4

11 RESISTANCE TO CAUSTIC FAIR TOPPOR

FAIR TOPOOR

12 RESISTANCE TO

SOLVANTS

EXCE-

LLENT

EXCELL

-ENT

13 SHRIANKAGE %

LINEAR

LESS THAN

2%AT 350 C

<2%

@ 900C

PROPERTY OF MATERIAL

INDICATING LOSS IN DIMEN

TION WHEN SUBJECTED TO

TEMPERATURE.

14 LEACHABLE CLORIDE <10ppm <10ppm

15 SPECIFIC GRAVITY

REAL

APPARENT

4.16

0.24

200-210

0.48

THE RATIO OF MASS OF SOL

MAKING UP MATERIAL TO

WEIGHT OF EQUAL VOL OF

WATER.THE RATIO OF SPECIFIC WT.

OF MATERIAL INCLUDING VTO EQUAL VOL OF WATER.

16 SPECIFIC HEAT 0.16 W/KG

0.15 W/KG

THIS IS REQUIRED TO KNOWHEAT STORAGE AND TEMP.

TIME LAG.

17 STRENGTH

COMPRESSIVE @5%-DO- @10%

412.17

Kpa600 Kpa

UPTO 25

MM60-80MIN

600 Kpa

>25MM

50-70 MIN

1200Kpa

PROPERTY OF MATERIAL

TO RESIST LOAD TENDINGTO SQUEEZE IT

18 STRENGTH FLEXURAL 262Kpa 241TO300

Kpa

ABILITY TO RESIST BENDING

WITH OUT BREAKING.

19 MODULUS OF RUPTURE 600Kpa

AT 982

DEG C

MIN 400

UPTO

25MM

858Kpa@

MIN 200

ABOVE 25MM

700 DEG

INDICATIVE OF CRUSHING

STRENGTH OF MATERIAL

20 TENSILE STRENGTH VERY LESS HIGH AS

DENSITYINCREASES.

THE PROPERTY OF MATERIA

WHICH MEASURES ITS ABILITO RESIST A STRESS TENDIN

TO PULL IT APART.

21 TEMPERATURE LIMIT

SERVICE

SHORT TIME

CONTINIOUS

650GR

--------

450 C

900 GR

----------

700 C

CALCIUM SILICATES HAVE

A INVERTION TEMP 675

WHERE AS ALUMINA HAS

INVERSION TEMPERATURE

OF 1150 C.



22 MELTING TEMPERATURE 1425 C 1425 C SILICATES HAVE INCONGUE

MELTING POINT.

23 THERMAL

DIFFSSSIBILITY

M2 /HR AT 38 C. 4.12 X

-7

10

2.58 X

-6

10

THE PROPERTY OF MATERIA

WHICH MEASURES THE TIME

RATE OF TEMPERATURE

MOVEMENT THROUGH IT.IN

CLCLIC OPERATION HIGH T.D

IS REQUIRED .IN FIRE PROOF

SLOW T.D. IS REQUIRED.24 THERMAL SHOCK

RESISTANCEEXCE--LLENT

EXCE--LLENT

ABILITY TO WITHSTANDRAPID CHANGE OF TEMP.

25 VIBRATION

RESISTANCE

FAIR

FAIR

GOOD ABILITY TO WITHSTAND

VIBRATIONS.

26 WATER ABSORPTION

% BY VOLUME

90 80

27 WATER VAPOUR

TRANSMISSIONPERM-CM

VERY

HIGHVERY

HIGH

NOT VERY

HIGH

RATE OF WATER VAPOUR

PENETRATION DUE TOPRESSURE DIFFERENCE.

28 THERMAL

CONDUCTIVITY W/M K DEG C.

MEAN TEMP Density 192kg/m3 Density 320kg/m3

93 0.052 0.052

149 0.061 0.00.076

260 0.091 0.0.092

370 0.110

480 0.128

29 SIZES

THICKNESS AVAILABLE

762x 1117 x 10 1000 X 500 X 25 STANDARD TOLERANCE

SHALL APPLY

30 LINEAR SHRINKAGE 2%AT

650 C

2% AT

900 C

31 CHEMICAL ANALYSIS

32 PRICES: RS 180/M2

650 GR. SIZE: 762 x 1117 x 10mm

SALES TAX: 15.3% M.S.T.

PRICES: RS 300/M2

SIZE: 1000 X 500 X 25 MM

SALES TAX: 15.3 % M.S.T.



C 518 Test method for Steady State Heat Flux Measurement and Thermal Transmission Properties by means of the Hea

Flow meter Apparatus.

C 553 Specification for Mineral Fiber Blanket and Felt insulation (Industrial type)

F 84 Test Method for surface Burning Characteristics of Building Material.

3 CLASSES

Classes of mineral fiber block and Board insulation are for use to the following temperatures

3.1.1. Class 1 ---- 204 deg C.

3.1.2. Class 2 ---- 204 deg C

3.1.3 class 3 ---- 454 deg C

3.1.4 class 4 ---- 538 deg C

3.1.5 class 5 ----- 982 deg C

ARK-THERMAL INSULATION ENGINEERING & TRADING CO.S ‘181’M.I.D.C. BHOSARI-26



3.2 These materials should be classified as rigid or semi rigid as tested in accordance with 11.1.1.

4 Terminology

4.1 Definitions C 168 shall apply to the terms used in these specifications.

5 Materials and Manufacture

5.1 Composition – The fiber shall be of mineral substance such as rock, slag or glass processed from a molten state into

Fibrous form Fibers under this specification is not asbestos.

5.2 Manufacture – Mineral fibers block and board thermal insulation shall be rigid or semi-rigid material composed of

Mineral fibers with or without binder.

6. Physical requirements

6.1 .1 Temperature of use- When tested in accordance with 11.1.7 at the intended use temperature, insulation for use

Above Ambient shall show no physical changes that adversely affect its service qualities.

6.1.2 Moisture Absorption (Water Vapor) –When tested in accordance with 11.1.8 insulation for use below ambient

Shall gain no more than 1.0% volume

6.1.3 Density- Density shown in Table 1 is for design purposes.

6.1.3.1 Density for Class 1,2,3, and 4 ---Delivered density shall not exceed that shown in table 1. When specified densitIs part of the purchase contract the specified density is a part of the purchase contract, the specified density (not delivere

Density) shall be based on a product containing 40% by weight.nonfibrous material (shot) that would be retained on a

100 mesh( 150µ m ) screen as determined by the test method in Annex A1, The density of the delivered product will

Vary that specified in direct proportion to the nonfibrous content of the delivered product. The delivered product density

Shall be determined based on single package units. The manufacturer shall furnish certification of the non-fibrous

Content of the delivered product.

6.1.3.2 DENSITY FOR CLASS 5-

Density shall not exceed that shown in table 1 .For delivered material the density shall be the specified density to which

A tolerance of no more than 10% may be applied.

STANDARD SIZES:

7.1 Standard sizes of mineral fiber block and board insulation shall be in accordance with Table 2

8 DIMENSIONAL TOLERANCE

8.1 The average measured length, width, and thickness of the insulation shall not differ from the standard dimensions

Specified by more than

8.1.1 length----12mm

8.1.2.width ---- 6mm

8.1.3 thickness---- 3mm

9WORKMENSHIP

9.1 The insulation shall not have visible defects that will adversely affect its service qualities.

10 SAMPLING

10.1 Sampling shall be conducted in accordance with method C390




ARK-THERMAL INSULATION ENGINEERING & TRADING CO.73/3/3 ; “NAMASTESTU”; BHAKTI MARG; FILM INSTITUTE ROAD;ERANDWANA PUNE-411004

FAX NO:020-5430501;PHONE:020-5461555/5469112; MOBILE:9823023950;E-MAIL:[email protected]

FACTORY: S ‘181’ M.I.D.C. BHOSARI, PUNE-411 026.FAX/PHONE:020-7122189

11 . TEST METHOD11.1 Determine the properties enumerated in this specification in accordance with the following method.

11.1.1 Regidity- Use a test specimen 1 in (25mm) thick ,32in (810mm) long and from 6 to 24 in (152 to 610 mm ) wide.

Place the specimen on two horizontal, parallel ½”in (13mm) mandrel supports 30 in (760mm) apart. Measure the sag in

The center of the span from a straight line connecting two points on the surface directly above the supports after 5 min

Has elapsed. Classify as rigid a material showing a sag not greater than ½”in (13mm) Classify as semi-rigid a material

Showing a sag greater than ½” in (13mm) but that is not sufficiently flexible to be bent 90deg over a ½” (13mm) mandre

Without rapture.

11.1.2 Density—See test method C303

11.1.3 Compressive Strength—See Test method C165

11.1.4 Thermal Conductivity –See Test Method C 177 or C518

11.1.5 Linear Shrinkage—See Test method C356

11.1.6 Surface Burning Characteristics—See Test Method E-84

11.1.7 Temperature Resistance-See Test Method C 411

11.1.8 Moisture Adsorption—Section 15 of Specification C 553

11.2 PRECISION AND BIAS

11.2.1 The precision and bias of the test procedure detailed in this specification have not been determined.

11.2.2 the precision and bias of the method identified herein in other ASTM method are as specified in those methods.

12 INSPECTION

12.1 Inspection of the material shall be made as agreed upon between the purchaser and the seller as part of the purchase

Contract.

13 REJECTION13.1 If the average of the test data obtained on the pieces tested fail to confirm to the requirements of this specification

Rejection may be made in accordance with the following procedure.

13.1.1 Take, prepare, and test a second SAMPLE FROM THE SAME LOT. Average the results of the retest with the

Results of the original test to determine compliance with this specification.

13.1.2 Upon retest as described in 13.1.1. failure to confirm to this specification shall constitute grounds for rejection.

13.1.3 In case of rejection, the manufacturer or seller shall have the right to reinspect the rejected shipment and resubmit

The lot after removal of that portion of the shipment not conforming to the specified requirements.

14. PACKAGING AND PACKAGE MARKING

14.1 PACKAGING: Unless otherwise agreed upon or specified between the purchaser and the manufacturer or seller

Mineral fiber Block or Board thermal insulation shall be packed in the manufacturer’s standard commercial containers

14.2 Marking- unless otherwise specified each container shall be plainly marked with the manufacturer’s name, the

Product name, class, quality, nominal dimentions, facing and accessories, if any, of the material in the container.




ARK-THERMAL INSULATION ENGINEERING & TRADING CO.73/3/3 ; “NAMASTESTU”; BHAKTI MARG; FILM INSTITUTE ROAD;ERANDWANA PUNE-411004FAX NO:020-5430501;PHONE:020-5461555/5469112; MOBILE:9823023950;E-MAIL:[email protected]


Table 1 – Physical Requirements of Block and Boards.

Properties Class

1 2 3 4 5

DENSITY (AVG) MAX-KG/M3 160 192 192 192 320COMPRESSIVE STRENGTH(AVG) MIN-

-LOAD REQUIRED TO PRODUCE A

REDUCTION IN THICKNESS OF 10%

KPa 4 --- 1.2 --- --- 48LINER SHRINKAGE (LENGTH) AFTER

SOAKING HEAT (AVG.) MAX % TESTED

AT MANUFACTURER’S TEMPERATURE

LIMIT Below2.0 Below2.0 Below 2.0 2.0 4.0

THERMAL CONDUCTIVITY (AVG) MAX.

DEG C W/m K AT MEAN TEMPERATURE

-4 0.035 0.035 - - -10 0.036 0.036 - - -24 0.037 0.037 - - -38 0.040 0.040 0.043 0.043 -93 0.50 0.50 0.52 0.52 -

149 - - 0.061 0.061 0.076260 - - - 0.091 0.092370 - - - - 0.110480 - - - - 0.128Surface burning charasteritics (all class)

Flame spread classification Not greater than 25

Smoke density Not greater than 50

Test in accordance with Recommended Practice C165, Procedure B except (l) use

Samples in 50.8mm thick 38.7 cm2 condition class 2 material at 204 deg c and class 5

Material at 982 deg C in accordance with Test method C411 before testing. Measure

Initial thickness of class 2 material while bearing a preload of 0.12kPa and class 5Material while bearing a preload of1.72 kPa.Contact the manufacturer for compressio

Strengths of class 1,3 and 4 material.




Will give an added benefit of nearly 12% added efficiency.

Summary:

Laboratory tests have shown that double layer, staggered joint construction is best

Method for insulation of pipes and equipments.ovens or even furnaces. Comparisons

Of heat losses of thick wall single layer and thick wall double layer construction

Showed that the heat loss for single layer construction averaged 12% higher than the

Heat loss using double layer construction.

Objective:

This project was designed to compare heat losses of thick insulation installed by

Different construction methods to develop information which can be used in the

Economic evaluation of single layer and double layer construction.

Description:Samples of 3 N 5-1/2” pipe insulation were made using single layer and staggered

Double layer sN3 and 9 N 2-1/2”. These samples were tested using method ASTM -

- C 335 STANDARD TEST METHOD FOR THERMAL CONDUCTIVITY OF

PIPE INSULATION. The test method was modified slightly to include an end joint

In the metered test section. This change makes the test more practical and less

Analytical.

As a check on the single layer test, a sample of single layer insulation was made by

Gluing two layers together.






RESULTS(THIS DATA WAS PUBLISHED BY PABCO INSULATION DIV.

IN THE PABCO TECHNICAL BULLETIN)

TABLE 1

THERMAL PERFORMANCE OF THICK

WALL PIPE INSULATION

APPARENT THERMAL CONDUCTIVITY

MEAN SINGLE GLUED DOUBLE LAYER Efficiency

TEMPERATUR ELAYER DOUBLE LAYER STAGGERED JOINT Improved

300 0.493 0.492 0.423 15%400 0.560 0.556 0.493 12%

500 0.636 0.629 0.560 12%

600 0.723 0.711 0.637 12%

Test Method – ASTM C-335- Standard Test Method for Thermal Conductivity of

Pipe Insulation. This test method was modified to include radial joint losses

ApparentThermal INCLUDES JOINT LOSSES

Conductivity

BTU/in/ft2 hr.F Single Layer

0.8

0.7 Glued Double Layer

0.6 StaggeredDouble Layer

0.5

0.4

0.30.2

MEAN TEMPERATURE 100 200 300 400 500 600

FIGURE 1 – APPARENT THERMAL CONDUCTIVITY

OF 3 N 5-1/2” PIPE INSULATIONARK –THERMAL INSULATION ENGINEERING & TRADING CO. S181 M.I.D.C. BHOSARI . PUNE-26





STEP 2 - APPLICATION OF THE ENERGY SAVINGRADIANT BARRIER AND REFLECTING FOIL MULTI LAYER BARRIER

The Three ways Heat is transferred are :

1. CONDUCTION: Conduction is the transfer of energy within a body or between two bodies

In physical contact. The transfer is from a higher temperature region to a low

Temperature region by tangible contact.

2. CONVECTION: Convection is the movement of mass, with its associated energy, from one

Location to another.

3. RADIATION: Radiation is the transfer of energy from higher temperature body, through

Space, to another lower temperature body or bodies some distance away. TruRadiation is the transfer of heat between these bodies which does not raise th

Temperature of medium through which the heat passes. This heat transfer is

Through electromagnetic waves, the most common example being the Sun.

Radiation is the form of transfer that most affects the common envelops and

Equipments. Up to nearly 83% of the total heat is thus transferred by radiatio

In case of Building envelops this quantum of radiation is upto 93%

Radiation Barriers work on simple and proven principle, Heat, like light, travels primarily by

Radiation, not convection (air currents) or conduction (contact). And just like light, the flow of heat

Can be reversed by simple reflection. One of the oldest applications of reflection combined with

Dead air spaces for insulation are the familiar vacuum bottle.

The first documented application of a radiant barrier was around 1872 ,when Sir James Dewar

Discovered that a reflective surface on one side of vacuum space could dramatically improve

Its ability to keep hot things hot and cold things cold. Since that development, the isolative propertie

Of reflective spaces has been a matter of scientific certainty. Neverthless, from the Dewar flask,

Ancestor of the modern thermos bottle, to the space suits of NASA’S astronauts, the saga of reflecti

Insulation has been one of vast possibilities yet unfulfilled.

In 1945 Dr Alexander Schwartz introduced an ingenious combination of multiple layers of Aluminu

Foil with a succession of dead air spaces, thus ushering in what promised to be a bright new era of Reflective building insulation. Since its secret was the ability to reflect infrared heat rays,Dr.Schwar

Named his new material INFRA.Architects, engineers and builders readily embraced this unusual bu

Scientific approach to their familiar insulation problems and by the early ‘60’s millions of square fe

Of radiant barrier had been installed.

ARK –THERMAL INSULATION ENGINEERING & TRADING CO. S181 M.I.D.C. BHOSARI . PUNE-26



The installation of radiant barrier and reflective insulation system is a permanent way

To reduce costs. You need make only one purchase, and pay for it one time. Once the

Purchasing cost of the radiant barrier system is recouped, you never again have to pay

Out for it, but you continue to save every year. Infact you will save more money every

Year because you’ll use about the same of amount of energy, but the cost of energy thYou save will have spiraled upwards yearly.

Florida Solar Energy Center have assessed the Thermal Performance of Radiation

Barriers and presented their results for the effectiveness as under.

TABLEEFFECTIVENESS RATIOS OF THREE ATTIC/ROOF INSULATION STRATEGIES

STRATEGY EFFECTIVENESSPLAIN FIBERGLASS BATT RSI 3.55(R019) (RAW 1.00

FIBERGLASS FACING RADIATING SURFACE

SINGLE FOIL LAYER (DOUBLE SIDED FOIL WITH 1.42

AIR SPACE ON BOTH SIDES OF FOIL

FOIL FACED FIBERGLASS BATT(R019) WITH 1.82

FOIL AND AIR SPACE FACING RADIATING

SURFACES)

Effective resistances for foil faced airspaces of various depths and for various

Directions of heat flow are given in ASHRAE HANDBOOK –1981 Fundamentals

Volume.

ARK-THERMAL INSULATION ENGINEERING & TRADING CO. S ‘181’M.I.D.C. BHOSARI-26





Radiant –barrier effective resistance is given by;

Reff = Σ ∆ T / Σ Q

Reff = effective resistance

∆ T = temperature difference across the composite section

Q = measured heat flux into interior space

Equation above represents the steady-state definition of thermal resistance. The

Summations used in this equation are optimally accumulated over a sufficiently long

Period so that Reff converges on a constant value. A number of factors affectThis convergence are -()

1. Mean temperature across the composite,

2. Difference in temperature ∆ T across the composite.

3. The thermal storage capacitance of the material and its associated time lag.

Running resistance calculations from measured block vent skin radiant barrier

Wall data showing effect of time lag on calculations.%Difference

Resistance 100 No time lag

Q lags ∆ T by 4 hours50

0

-50

Re = Σ ∆ T/ Σ Q-100

-150 5 10 15 20 25 30 35 40 45 50 55 60 65 70




ARK-THERMAL INSULATION ENGINEERING & TRADING CO.73/3/3 ; “NAMASTESTU”; BHAKTI MARG; FILM INSTITUTE ROAD;ERANDWANA PUNE-411004



Difference in mean temperature produce slight variation in material conductivity k Therefore, affect thermal resistance. Large temperature differentials appear to

Cause more rapid convergence than small ones in massive components. Finally, the

Thermal storage capacitance and associated time lag of composites can have

Substantial effect on Reff.The time lag associated with this transfer process may be

Relatively short for frame sections with low mass/storage.

At multiple reflections of heat with each foil separated by low mass boards (having

-Low heat storage will at each stage reflect back the heat to the source.

Some typical values for emissivity of surfaces are given below

TABLE OF EMISSIVITY CO-EFFICIENTS

NATURE OF SURFACE TEMPERATURE OF SURFACE38 DEG C 260 DEG C

ALUMINUM – POLISHED 0.04 0.06

ALUMINUM – OXIDIZED 0.11 0.12

WHITE SURFACES-WHITE OR CREAM 0.95 0.88

DARK PAINTED SURFACE 0.95 0.90

ALUMINUM PAINTS 0.65 0.64

IRON & STEEL – POLISHED 0.06 0.08

IRON & STEEL –POLISHED CASTING 0.07 0.10

IRON & STEEL –OXIDIZED CASTING 0.63 0.66

ROUGH STEEL PLATE 0.94 0.97

OXIDIZED STEEL PLATE 0.79 0.79

CALORISED STEEL PLATE 0.50 0.53FABRIC FINISHES- PAINTED (APPROX) 0.95 0.90

ZINC INCL G.I. STEEL POLISHED 0.04 0.06

ZINC INCL G.I. STEEL OXIDISED 0.11 0.12


ARK-THERMAL INSULATION ENGINEERING & TRADING CO.



73/3/3 ; “NAMASTESTU”; BHAKTI MARG; FILM INSTITUTE ROAD;ERANDWANA PUNE-411004



HEAT LOSS AND SURFACE TEMPERATURE FOR DIFFERENT EMISSIVITIES

O.D.IN EMISSIVITY Fc+fr CORRESPONDING SURFACE

HEAT LOSS TEMP. DEG .FPIPE b.t.u.per sq.ft .hr

2” 0.1 1.005 32 x 1.0005=32.2 116

2 0.9 1.897 32x `.987 = 60.7 102

16” 0.1 0.642 32x0.642=20.5 135

16” 0.9 1.534 32x1.534=49.1 100

From the above it is observed that with highly polished surfaces corresponding heatLoss is reduced and surface temperature is increased.

How the multiplayer system worksTransient temperatures in a translucent, two layer composite following the sudden

Application of radiation to the boundary at x =0. Scattering in the first layer shields

The second layer from incident radiation, resulting in low temperature in the second

Layer.(optical thickness of layer,k;refractive index,n; scattering albedo,Ω thickness

Of composite, D; and initial temperature Ti) The similar phenomenon will appear

In a subse

1.30

Dimension INTERFACE Layer 1Less 1.25 K1=10

Temperature Ni=1.5

T(x,t)/Ti 1.20 Ω I= 099

1.15 LAYER 2

K2=5

1.10 N2=3

Ω 2=0

1.05

1.00

0.0 0.2 0.4 0.6 0.8 1.0

Dimensionless position x/DARK-THERMAL INSULATION ENGINEERING & TRADING CO. S ‘181’M.I.D.C. BHOSARI-26





INFLUENCE OF DENSITY IN THE INSULATION

DENSITY OF THERMOFIT BOARDS IS 300KG/M3 AS AGAINST THE 120KG DENSITY OF

ROCKWOOL IT WAS OBSERVED AT M/S PRIMA ENGINEERING INDUSTRIES WHO ARE

MANUFACTURING BREAD BAKING OVENS WITH TEMPERATURES OF 300 DEG. C.

WITH 150MM INSULATION OF L.R.B. ROCKWOOL MATTRESS AND 1/2 INCH PLASTER OF PARIS WITH 50 MICRON ALUMINUM FOIL AS REFLECTING BARRIERS GAVE

SURFACE TEMPERATURE OF 71 DEG C WITH COST OF INSULATION FOR THE BATCH

TYPE OVEN AS Rs 13,500/=. WHEN WE SUGGESTED THE THERMO FIT BOARDS WITH

TWO INCH INSULATION IN TWO LAYERS DULY STAGGERED JOINTS, GAVE THESURFACE TEMPERATURE OF 65 DEG C WITH THE COST OF Rs 9,500/= THUS MAKING

A SAVING 30% IN COST OF MATERIAL. THIS HAPPENS BECAUSE OF THE RADIATIVE

COMPONENT OF HEAT LOSS IS DEPENDENT ON DENSITY AND DENSITY OF

THERMO FIT BOARDS IS 300KG/M3. IT IS EXPLAINED AS UNDER.

INFLUENCE OF DENSITY IN THE INSULATION FOR A GIVEN FIBERIZING CONDITIONS AND AT A FIXED TEMPERATURE THETHERMAL CONDUCTIVITY IS GIVEN BY

λ T = A + B ρ + C/ ρ

WHERE A,B,C ∂λ / ∂ρ ARE FUNCTIONS OF TEMPERATURE

THUS WE CAN WRITE

δ λ / δ ρ = B - C/ ρ 2 = f ( T,ρ )

THE C / ρ FORM REPRESENTS THE RADIATIVE COMPONENT OF THE HEATTRANSFER AND CONSEQUENTLY, AN INCREASE WITH TEMPERATURE C

INCREASES AS T INCREASES. THERE FORE FOR A GIVEN DENSITY THE SLOP

OF THE CURVE λ = f ( ρ ) INCREASES WITH TEMPERATURE .THIS MEANS THAT THE INFLUENCE ON THERMAL CONDUCTIVITY IS EVEN

GREATER AT HIGHER TEMPERATURES.

TO QUANTIFY THIS INFLUENCE IN A GIVEN CONFIGURATION THE

δ λ / δ ρ AT 400ºC ≅ δ λ / δ ρ 24 º C

100KG/M3 30KG/M3

ARK – THERMAL INSULATION ENGINEERING & TRADING CO. S 181 M.I.D.C. BHOSARI PUNE-411 026

IS DECREASED.

aaaa miracles do not happen

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