Thermal Insulation Handbook for the Oil, Gas, and Petrochemical Industries

1.10. Calculation of Thickness of Insulating Material Required to Prevent Condensation

The limiting condition for the formation of condensation on the surface of an insulating material occurs when the surface temperature equals the dew point temperature, θd, i.e., when θ₂ = θ_d.

Q=θ1−θ2R=θ1−θmR+RS

(1.44)

Table 1.24

Cold Insulation Thickness for Energy Conservation/Condensation Prevention

Pipe or Equipment, Outside, mm	Normal Insulation Thickness, mm
	25	38	50	64	75	89	100	114	125	140	150
	Minimum Temperature, °C
To 33.4 mm	5	-12	-32	-54	-79	-107	-137	-176	-223	-	-
48.3	7	-7	-34	-54	-73 ...