The shear effect on the viscoelastic soft scale of heat exchangers is simulated in this study, focusing on a chemical company’s heat exchanger and the associated fouling on its inner tube shell wall. The finite element software ABAQUS simulates the ultrasonic descaling process, incorporating viscoelastic soft scale materials into the calculations through software fitting functions. Based on ABAQUS data transfer technology, the model was first subjected to implicit static analysis, followed by explicit kinetic analysis containing pre-stress. The vibration propagation of ultrasonic waves on the heat exchanger model was simulated under different working conditions. Distribution of shear stresses of the fouling on different paths of the pipeline wall was obtained, and the results revealed the influence of different parameters of the ultrasonic waves on the shear descaling effect, which provides a reference for selecting appropriate parameters to improve the efficiency of ultrasonic descaling.