Through the heat transfer analysis of the experimental loop of the insulated crude oil, the calculation model of the experimental loop temperature field of the insulated waxy crude oil was established.The internal temperature distribution of the pipeline and the variation of the temperature gradient of the inner wall of the pipeline were calculated.The effects of different ambient temperature,oil flow velocity and wax formation on the temperature field distribution of the pipeline were studied.The results showed that the greater the temperature difference between the oil temperature in the tube and the cooling water in the casing,the larger the average temperature gradient of the tube wall.The average temperature gradient of the pipe wall increased as the oil flow velocity increased,however,when the temperature gradient of the inner surface of the sediment deposit layer on the pipe wall was lower than the initial time, the magnitude of the decrease gradually decreased as the length from the inlet end increased.

In the pipeline operation, the phenomenon of wax deposition often occurs, which will lead to the reduction of the volume of transmission and even the occurrence of condensation accident. For Songshan⁃Huludao thermal insulation crude oil pipeline conveying Qingji mixed oil, a self⁃made indoor thermal insulation ring experimental device wasdeveloped, and a stepwise regression model and a support vector machine model of wax deposition rate were established. The results of comparison and verification showed that the stability and accuracy of the support vector machine model were higher than that of the stepwise regression model. The wax deposition rate model was used to predict the wax deposition in different seasons, which provided a theoretical basis for the determination of the optimal paraffin removal period.