A method for determining the low cycle fatigue of welded joints in components of pipeline bandage of compressor stations of transmission gas pipelines

摘要

An experimental-calculation method was proposed for evaluating the low cycle fatigue strength and endurance of welded joints in bandaged pipelines of the compressor stations of transmission gas pipelines. The results show that the high frequency component of the stresses may greatly reduce the endurance of the joints, regardless of the magnitude of this component. The low frequency amplitude of strains was represented by its maximum value in prophylactic complete shutdown and activation to the standard pressure of gas in the investigated zone. Comparison of the experimental data on the low cycle strength and endurance of the actual welded joints of the same type in long-term service makes it possible to evaluate with sufficient reliability the possible degradation of the metal of the welded joint and determine the guaranteed service life.