The known pipe diameters are 2 ", 3", 4 ", and 6", respectively. The pipe material is carbon steel, the medium is water, and the temperature is maintained at 5 degree . The minimum environmental temperature is -20 degree . The insulation material is rock wool, and the thickness of the insulation layer is 50mm. The heat loss of each meter of electric heating pipe is calculated separately.

Q=q × Δ T × K × C × E (w/m)

Q - Heat dissipation per meter of pipeline (W/m)

Q - Heat dissipation of the pipeline (at 1 degree /m)

TW - Maintain temperature

TH - Minimum ambient temperature

Δ T ------ TW TH

K - Thermal conductivity of insulation materials

C - Correction coefficient of pipeline material

E - Safety factor

(1) Calculate temperature difference

Δ T=TW – TH=5- (-20)=25

(2) Calculate the heat dissipation per meter of pipeline

K=0.044

Q1=7.05

Q2=9.03

Q3=10.83

Q4=14.6

C1=1

E=1.2 (usually taken as 1.2)

Q1=Q1 ×Δ T × K × C × E=7.05 × twenty-five × zero point zero four four × one × 1.2=9.306 W/m

That is, the heat loss per meter of pipeline is 9.306 W ＜ 25W (25W is the power of the electric tracing band provided by our company)

Q 2=q2 ×Δ T × K × C × E=9.03 × twenty-five × zero point zero four four × one × 1.2=11.9196 W/m

That is, the heat loss per meter of pipeline is 11.9196 W ＜ 25 W

Q 3=q3 ×Δ T × K × C × E=10.83 × twenty-five × zero point zero four four × one × 1.2=14.2956 W/m

That is, the heat loss per meter of pipeline is 14.2956 W ＜ 25 W

Q 4=Q1 ×Δ T × K × C × E=14.6 × twenty-five × zero point zero four four × one × 1.2=19.272 W/m

That is, the heat loss per meter of pipeline is 19.272 W ＜ 25 W

In summary, the power provided by the electric heat tracing used in the four sizes of pipelines mentioned above is greater than the heat loss, which means that the temperature in the pipeline can still be higher than 5 degree in an environment of -20 degree .