Abstract: In order to reduce the construction cost of oilfield projects in the African market, a scheme is proposed to guarantee the safe operation of the inlet and outlet lines in pigging stations without anchor block. This paper takes a project in Chad as an example, establishes a model for stress analysis by CAESAR II software with the overall consideration of the ASME design standards and the external forces of piping system. The design scheme is optimized by comparing and analyzing the traditional anchor block installation method, the flexible installation method and the flexible installation method with foundation bolts. The model analysis of flexible installation method with foundation bolts is more accurate. Elbows with large radius of curvature on the inlet and outlet lines in pigging stations are set up using the method without anchor block to absorb most of the thermal expansion stress of buried piping, reduce the horizontal thrust on the pig launcher, reduce the investment and ensure the safe operation of the pipelines

Key words: Pigging station, Stress analysis, Buried piping, Overhead line, Anchor block