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k calc

k=a*exp(b*t) a b

0.0329 0.00298

Mean Calculated Brochure at atTemp Deg C value value (185) Hot face Cold face

50 0.038 0.039 100 0

100 0.044 0.046 150 50

150 0.051 0.053 200 100

200 0.060 0.061 250 150

250 0.069 0.069 300 200

300 0.080 0.081 350 250350 0.093 0.093 400 300

400 0.108 0.106 450 350

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Worksheet designed by: Tom Smales

Isover South Africa

Client

Date

SINGLE STONEWOOL PIPE SECTION

HEAT LOSS ALONG A PIPE

Parameter Term Units Value Remarks

Inlet temp. of liquid ti deg C 5 Enter inlet temperature

Required outlet temp of liquid to deg C 8 Enter required outlet temperature

Mean temperature of liquid tL deg C 7

Mean temperature of insulation tm deg C 13

Ambient air temperature ta deg C 20 Enter actual ambient temperature

Thickness of insulation d metres 0.050 Use this as the 'by changing cell' in GOAL SEEK

Thermal conductivity k W/m.K 0.034

Safety factor % 0%

Surface heat transfer coefficient f W/m2.K 10 Aluminium=5.7, galvanised steel=6.3, unclad=10

Pipe diameter d metres 0.114 Enter actual pipe external diameter

Lagged pipe diameter ds metres 0.214

Factor ln (ds/d ) 0.630

Max. allow. heat gain/loss(-) watts 0

% other incidental heat gain/loss % 10%Net max.heat gain/loss(-) watts 0

Resistance of insulation Ri m2.K/W 1.049

Resistance of surface R m2

K/W 0 053

7/27/2019 Stonewool Pipe Calculation2-IsULATION

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Worksheet designed by: Tom Smales

Isover South Africa

Client

Date

SINGLE STONEWOOL PIPE SECTION

EXTERNAL TEMPERATURE/INSULATION THICKNESS

Parameter Term Units Value Remarks

Surface temperature of pipe tp deg C 500 Enter actual pipe temperature

Ambient air temperature ta

deg C 20 Enter actual ambient temperature

External surface temperature ts deg C 50 Enter required insulation surface temperature

Mean temperature of insulation tm deg C 275

Thickness of insulation d metres 0.133 Use this as the 'by changing cell' in GOAL SEEK

Thermal conductivity k W/m.K 0.075

Safety factor % 0%

Surface heat transfer coeffic ient f W/m2.K 6.3 Aluminium=5.7, galvanised steel=6.3, unclad=10

Pipe diameter dp metres 0.200 Enter actual pipe external diameter

Lagged pipe diameter ds metres 0.465

Factor ln (ds/dp) 0.845

Heat flow Q' W/m 251.4

External surface temperature ts deg C 47.3 Use this as the 'set cell' in GOAL-SEEK

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Rockwool Pipes

Page 4

y = 0.0329e0.003xR = 0.9992

0.03

0.035

0.04

0.045

0.05

0.055

0.06

0.065

0.07

0 50 100 150 200 250 300

k(W/mK)

Mean Temperature Deg C

Stonewooll Pipe Sections

Series1

Expon. (Series1)