1 units, conversion factors and tables – Roxul Industrial Insulation Process User Manual
Page 147
3.1 Units, conversion factors and tables
3.1.13 Conversion of pressure scales
3.1.14 Conversion of SI-units into Imperial units, pre-SI units and technical scales
Unit
Pascal
(Pa)
Bar
atm
lb/sq ft
lb/sq in.
Pascal (Pa)
10
-5
9.869 * 10
-6
0.201
1.450 * 10
-4
Bar
10
5
0.987
2088.5
13.50
atm
101325
1.013
2116.2
14.70
lb/sq ft.
47.88
4.788 * 10
-4
4.723 * 10
-4
6.944 * 10
-3
lb/sq in.
6894.8
0.0689
0.0680
144.00
Symbol
Quantity
SI-Unit
Technical scales
Imperials units
Q
Heat. energy
J
kcal = 4186.8 J
1 BTU = 1055.06 J
Q
Energy. heat flux
W/m
2
kcal = 1.163 W
m
2
h
m
2
1 BTU
= 3.1546
W
(sq.ft.hr.)
m²
λ
Thermal conductivity
W/(m K)
kcal
= 1.163
W
m
2
h
(m K)
1 BTU
= 1.7307
W
(ft.hr.°F)
(m K)
1 BTU in
= 0.1442
W
(sq.ft.hr.°F)
(m K)
1 BTU
= 20.7688
W
(in.hr.°F)
(m K)
R
Heat resistivity coefficient (R-value)
m
2
K/W
1 m² h
K
= 0.86 m²
K
kcal
W
1 sq.ft.hr.°F = 0.1761 m
2
K
BTU
W
α
Heat transfer coefficient
W/(m
2
K)
kcal
= 1.163
W
(m² h K)
(m
2
K)
1 BTU
= 5.6783
W
(sq.ft.hr.°F)
(m
2
K)
Cp
specific heat capacity
kJ/(kg K)
kcal
= 4.1868
kJ
(kg K)
kg K
1 BTU
= 4.1868
kJ
(lb. °F)
(kg K)
C
Radiant coefficient
W/(m
2
K
4
)
kcal
= 1.63
W
(m
2
h K
4
)
(m
2
K
4
)
1 BTU
= 33.156
kJ
(sq.ft.hr.°R
4
)
(m
2
K
4
)
144