INSULATED PIPES ABOVE THE GROUND
Rule of thumb for the required power in normal cases:
Required power 10 W/m pipe:
– if the pipe diameter is max. 50 mm
– if the insulation is min 50 mm mineral wool
– the lowest ambient temperature is -30°C
In other cases the required power is calculated as per below:
P/m = 2 x π x dt x k x S / In (dy / di)
|P/m||=||required power in W/m|
|dt||=||The difference in temperature in °C.
(the lowest permitted temperature of the medium minus the lowest frequent ambient temperature).
|k||=||The permeability of the insulation material in W/m°C (J/m°C x 1.16)
For mineral wool 0.046 W/m°C
|S||=||Safety factor, is put to 1.3 -1.7 depending how it is exposed to weather and wind.|
|dy||=||The interior diameter of the insulation in mm.|
|di||=||The outer diameter of the pipe in mm.|