Steam is flowing through an insulated steel pipe shown in the fig, is losing heat to the surroundings. The details are as follows

Inner radius of steel pipe $$=50mm,$$
Outer radius of the steel pipe $$=57mm,$$
Outer radius of insulation $$=157 mm,$$
Thermal conductivity of steel $$=43$$ $$W/mK$$
Thermal conductivity of insulating material $$=0.1$$ $$W/mK$$
Heat transfer coefficient on steam side $$ = 570W/{m^2}K$$
Heat transfer coefficient on air side $$ = 12W/{m^2}K,$$
Temperature of steam $$ = {500^ \circ }C$$
Temperature of surroundings $$ = {30^ \circ }C$$

Calculate the heat loss per meter length of pipe and temp of the outer surface of the insulation.

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