提出了一种高含蜡胶凝油屈服测试方法,量程范围较常规方法宽。基于此研究了低温下测试油蜡混合物胶凝油的屈服特性,详细阐明了熔蜡温度、熔蜡温度下的静置时间和屈服应力测试温度下的静置时间对特高含蜡胶凝油屈服特性的影响。研究发现,熔蜡温度越高,胶凝油的屈服应力越小;熔蜡温度下静置时间越长,油蜡混合物的低温屈服应力越大;胶凝油受屈服应力测试温度下静置时间影响较小。静置时间超过30min,其屈服值基本一致。研究结果对于科学制备高含蜡胶凝油,进而探索清管过程中蜡层剥离机制具有重要意义。
The gelling oil with high wax content can be used to simulate the wax deposit inside the pipelines. In this paper, a new yield stress measurement method for gelling oil With high wax content was presented. It has a wider measurement range compared to regular measurements. Thus, the yielding behavior of oil-wax mixture in low temperatures was further studied. In particular, the effects of melting temperature, standing time in melting and measurement temperatures on yielding behavior were presented for oil-wax mixture. It is found that high melting temperature contribute to a low yield stress. The yield stress of gelling oil increases with the increase in standing time in melting temperature. Within 5 h standing time, the yield stress is kept constant. In addition, the effect of standing time in measurement temperature on yielding behavior can be ignored. The yield stress remains basically unchanged while standing time in measurement temperature is more than 30 min. These conclusions are of great significance in preparing gelling oil with high wax content. It forms the basis for exploring the wax breakage and removal mechanisms during pipeline pigging.