The oil and gas pipeline companies in China are facing unprecedented opportunities and challenges because of China’s increasing demand for oil and gas energy that is attributed to rapid economic and social development. Limitation of land resource and the fast urbanization lead to a determinate result that many pipelines have to go through or be adjacent to highly populated areas such as cities or towns. The increasing Chinese government regulation, and public concerns about industrial safety and environmental protection push the pipeline companies to enhance the safety, health and environmental protection management. In recent years, PetroChina Pipeline Company (PPC) pays a lot of attention and effort to improve employees and public safety around the pipeline facilities. A comprehensive, integrated HSE management system is continuously improved and effectively implemented in PPC. PPC conducts hazard identification, risk assessment, risk control and mitigation, risk monitoring. For the oil and gas stations in highly populated area or with numerous employees, PPC carries out quantitative risk assessment (QRA) to evaluate and manage the population risk. To make the assessment, “Guidelines for quantitative risk assessments” (purple book) published by Committee for the Prevention of Disasters of Netherlands is used along with a software package. The basic principles, process, and methods of QRA technology are introduced in this article. The process is to identify the station hazards, determinate the failure scenarios of the facilities, estimate the possibilities of leakage failures, calculate the consequences of failures and damages to population, demonstrate the individual risk and social risk, and evaluate whether the risk is acceptable. The process may involve the mathematical modeling of fluid and gas spill, dispersion, fire and explosion. One QRA case in an oil pipeline station is described in this article to illustrate the application process and discuss several key issues in the assessment. Using QRA technique, about 20 stations have been evaluated in PPC. On the basis of the results, managers have taken prevention and mitigation plans to control the risk. QRAs in the pipeline station can provide a quantitative basis and valuable reference for the company’s decision-making and land use planning. Also, QRA can play a role to make a better relationship between the pipeline companies and the local regulator and public. Finally, this article delivers limitations of QRA in Chinese pipeline stations and discusses issues of the solutions.

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Dents in buried pipelines can be formed due to a number of causes: third party machinery strikes, rock strikes during backfilling, pipe resting on rock, and amongst others. Dents in pipelines would not only affect short and/or long-term integrity, but would also have a potential impact on the pass capacity of in-line inspection and cleaning tools when the size of the dent is large enough. Rebound for an originally constrained dent can decrease the dent depth and improve the pass capacity of in-line inspection and cleaning tools. In order to estimate the rebound capacity of dents especially in spiral weld pipelines, a full-scale dent rebound testing program of X65 steel pipeline was designed and performed. The full scale testing was conducted on the parent material and the spiral welds. Hemispherical and pyramidal indenters were used to generate dents to different depths. Strains around the denting area during formation of the dent and changes in depths due to rebounding after removing indenter were measured. Following each rebound test, the dent profile was portrayed with a 3D laser scanner and the maximum equivalent strain was then calculated. With the information obtained from the above measurements, detailed analyses were performed and a numerical model was developed. In this paper, the approach used for the study is described first. The results and findings are then presented. The effectiveness of the developed numerical model for dent integrity management is demonstrated.

Traditional result oriented IT's appreciation model satisfied businesses requirement seldom. Instead, process oriented one-REJ framework gave rise to attention. So far, this framework considered much less disbenefits from changing environment, systematic reliability risks, and utilization risks. This paper conducted four process factors and constructed a framework to analyze above problems qualitatively by introducing three risk variable factors, and discussed it further.