Stress Analysis of Gas Pipeline inside a Tunnel during Pigging Process

Pigging is one of the basic measures used to guarantee long-term pipeline safety during transmission, and is often used after pressure testing and in normal working conditions. In China most of the natural gas pipelines are distributed in hills, mountains and other large areas, but terrain height has no effect. Due to the pipeline stress factors on pipe walls thought to be related to the cleaning process involved in the gas pipeline stress model, this paper offers an appropriate pigging transient model in order to simulate the stress on pipeline walls more accurately, analyze the effects of pigging for gas transmission pipeline quantitatively and offer guidance in the furtherance of pigging operation knowledge.