Method and suggestions on control of pigging speed of low throughput pipeline

In the initial stage of operation, or due to the fluctuation of user requirements, the actual throughput of gas pipeline is generally less than the designed value, which results in the pig failing to reach the prescribed range of pigging speed, thus adversely influencing the pigging effect, even causing the accidents such as pig blockage. Therefore, study was performed based on Tai'an—Qingdao—Weihai Natural Gas Pipeline. Specifically, the operation condition of pipeline and the characteristics of pigging parameters in multiple rounds of pigging-based in-line detection were analyzed. Meanwhile, the method and suggestions on control of pigging speed applicable to the low-throughput condition were put forward. According to the results, the pigging speed can be effectively adjusted through three-staged pressure regulation, coordinated regulation of average pressure and throughput, regulation with full use of hub station, and optimization of the pig tracking and monitoring strategies and skills, so that the pig can run stably in the pipeline and satisfy the requirements of pigging speed for inline detection. In conclusion, the research results could provide experience reference for the pigging operation of pipeline under low throughput condition, and further ensure the safety of pipeline pigging.