Thermal insulation design includes selection of main insulation materials, determination of insulation thickness and design of insulation structure. The manufacturers of thermal insulation discuss their views on these.

The thermal insulation structure of the heat pipe can be selected according to the way of pipe laying, that is, indoor, outdoor, overhead, trench, direct burial, weather condition rainfall, outdoor temperature, atmospheric humidity and environmental conditions, and whether there are corrosive gases around it. The thermal insulation thickness of the heat pipe is usually determined by the minimum annual cost method, which makes the annual cost of heat dissipation of the pipe heat loss and the minimum heat insulation layer thickness as the economic insulation thickness. The economic insulation thickness of the pipeline is mainly related to the temperature of the medium, the ambient temperature, the annual operating time, the thermal conductivity of the thermal insulation material, the heat price and the price of the insulation material and the protection layer. For a specific project, the first four parameters are fixed values, so the economic insulation thickness is closely related to the price of heat, insulation materials and protective layer. The economic insulation thickness of the thermal pipeline is solved by solving the nonlinear equations by computer. For pipeline insulation design, insulation structure and economic insulation thickness have certain rules to follow. The key and difficult point is the choice of thermal insulation materials.

There are many kinds of insulation materials used in the project, such as new thermal insulation materials, such as rock wool, ultrafine glass cotton and aluminum silicate fiber, etc., when choosing insulation materials, in order to use as little investment as possible to achieve the best thermal insulation effect, that is to choose a high cost performance insulation material, we should master the performance and price of common insulation materials in detail, and then accordingly. Make a judgment on the specific project.