The invention belongs to the technical field of pipeline
welding, and particularly discloses a
welding prediction method and device suitable for a
new energy natural gas pipeline. The method comprises the following steps: acquiring a
load spectrum containing pressure fluctuation, temperature cycle and
hydrogen partial pressure change; setting a target fatigue life threshold value; calculating a three-dimensional
residual stress field through a thermal-mechanical
coupling finite
element model; the load spectrums are superposed, a critical plane method is combined with a Smith-Watson-Topper damage model to calculate the fatigue
crack initiation life, and a
hydrogen environment correction factor is introduced to quantify the
hydrogen influence; with the standard reaching of the fatigue life as the constraint,
welding parameters are optimized through an improved non-dominated sorting
genetic algorithm; and outputting the optimal parameters to a welding
system. According to the method, the problem that traditional welding
parameter design lacks dynamic load and hydrogen environment
coupling prediction capacity is solved, reverse design for reversely deducing process parameters from service requirements is achieved, and the reliability of welding quality and process formulation efficiency are remarkably improved.