A schedule number 40 standard steel pipe (outer diameter 4.5 in. and wall thickness 0.237 in.) carrying steam is lagged (insulated) with two layers. First layer (near the steel pipe) having 50mm thickness is made of 85% magnesia and second layer having 60 mm thickness is made of cork. The inner surface temperature of the steel pipe is maintained at 150°C and the outer surface temperature of the cork is maintained at 35°C. Determine the individual thermal resistance of each layer and the rate of heat loss per meter length of the pipe. Consider only the conduction heat transfer. Make suitable assumptions if necessary? (Take
1 in.= 2.54 cm)
Steel pipe. 45(W/(m-°C)
85% magnesia. 0.07 "
Cork 0.043 "
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