1 Design thermal load. There should be some room between the heat load and the effective heat load of the heat-conducting oil furnace, and this range is generally 10% to 15%.
2 Design temperature. 的设计温度由其使用温度决定，并应参照 GB9222《水管锅炉原件强度计算》中的有关规定进行设计。 The design temperature of the heat-conducting oil furnace is determined by its use temperature, and it should be designed in accordance with the relevant provisions in GB9222 "Strength Calculation of Water Tube Boiler Original Parts".
3 Design pressure. The design pressure of the heat transfer oil should be slightly higher than the maximum working pressure and should not be less than the opening pressure of the safety valve. The design pressure of the gas phase furnace is 1.2 to 1.5 times the working pressure; the design pressure of the liquid phase furnace should be 1.05 to 1.2 times the pressure; the inlet and outlet pressure difference of the heat transfer oil of the liquid phase furnace should be greater than 0.15 MPa (1.5 kgf / cm2).
4 Temperature of heat transfer oil inlet and outlet. The design should be from the perspective of both economy and safety, and design a suitable temperature difference for the operation of the heat transfer oil in the system. This temperature difference should be less than 30 ° C.
5 Flow rate of thermal fluid in the tube. Design a certain flow rate of heat transfer oil in the tube, and not cause coking due to local overheating. Generally, the radiation section tube uses a flow rate of 2 ~ 4m / s, and the convection section tube uses a flow rate of 1.5 ~ 2.5m / s. The determination of this parameter should also take into account the hot oil resistance in the tube and the factors that ensure that the hot oil flows turbulently in the tube. Larger tube diameters result in higher flow rates; smaller tube diameters require lower flow rates.
6 The average thermal strength of the furnace tube. The design requires that the average heat intensity of the furnace tube is within a certain range, so that the heat transfer oil is not overheated, and the heat transfer area of the furnace tube can be fully utilized. The average thermal intensity of the furnace tube in the general radiation section is 0.084 ~ 0.167GJ / (m2.h), and the average thermal intensity of the six-stage furnace tube is 0.033 ~ 0.047GJ / (m2.h);
7 Exhaust temperature. According to the working temperature of the heat-conducting oil during operation, the difference between the exhaust temperature and the temperature of the heat-conducting oil is best controlled at 80 ~ 120 ° C, and the exhaust temperature is suitably 350 ~ 400 ° C, so that the convection heating surface is not too large. In order to make full use of the thermal energy, some of the higher exhaust temperature heat removed by the heat-conducting oil furnace should be set up with a waste heat recovery device to recover and reuse it, especially the larger heat-conducting oil furnace should be considered and valued.
8 All pipes and accessories that are in contact with heat-conducting oil are strictly prohibited from being made of non-ferrous metals and cast iron. The flanges and valves should be cast steel valves with a nominal pressure of 2.5 MPa (about 25 kgf / cm2) and above. Seals should be made of high temperature and oil resistant materials. Use biphenyl mixture type heat transfer oil and apply tongue and groove or concave-convex flange connection.
9 The thermal oil furnace must be equipped with a low-level drain valve, and it is required to drain the material to ensure that no residual liquid is left