Prediction of optimum thermal insulation thickness for oil and gas process piping and equipments using simple method

Selection and determination of optimum thickness of insulation is of prime interest for many engineering applications. In this study, a simple method is developed to estimate the thickness of thermal insulation required to arrive at a desired heat flow or surface temperature for flat surfaces, ducts and pipes. The proposed simple method, which is easier than current available models involving a large number of parameters, requiring more complicated and longer computations, covers the temperature difference between ambient and outside temperatures up to 250°C and the temperature drop through insulation up to 1000°C. The proposed correlation calculates the thermal thickness up to 250 mm for flat surfaces and estimates the thermal thickness for ducts and pipes with outside diameters up to 2400 mm. The accuracy of the proposed method was found to be in excellent agreement with the reported data for wide range of conditions where the average absolute deviation between reported data and the proposed method is around 3.25%. The method is based on basic fundamentals of heat transfer and reliable data. Therefore the formulated simple-to-use expression is justified and applicable to any industrial application. The correlation proposed in the present work is novel and unique expression which is non-existent in the literature. This is expected to benefit and making design decisions which could lead to informed decisions on the selection of optimum insulation thickness for a given application in any process industry.