Abstract: The article gives brief introduction of the design principle and structure of the improved heating device in floating-roof storage tank and analysis is carried out on the security and reliability of the high gel point crude oil under the application of intermittent heating condition. Simulating experiments are conducted with a model tank established for the purpose. The result shows that the newly-designed healing device is capable of degrading the gel partly gelled in the tank due to intermittent heating, quickly get the tank back to operation and it is feasible for low temperature storage of high gel point oil at.