Abstract: In this paper, a simulation experiment device based on small loop was built up to study the restart laws ofwaxy crude oil after shutdown and guarantee the safe operation of pipelines. Several problems were discovered during theshutdown and restart debugging experiment, such as poor data consistency, unconformity between the yield value and theactual value of the oil sample, high evaporation of light components and inaccurate temperature control, so the loop wastransformed. Then, a set of reasonable operating methods and steps were developed. Finally, the effects of rest time, thermaltreatment temperature, restart frequency, restart temperature, static cooling rate and other factors on the restart pressure wereanalyzed. It is indicated that the optimized experiment loop can accomplish shutdown and startup experiments on differentoil samples in the test sections with different diameters, and it is conducive to the studies on the shutdown and startup ofwaxy crude oil.