Quantitative non-destructive evaluation of wall thinning in carbon steel piping is a difficult and urgent issue for safety of nuclear power plants. In this study, a magnetic saturation PECT (pulsed eddy current testing) method is proposed for this purpose, where a magnetic yoke is utilized to generate strong static magnetic field to saturate the piping material and to increase the skin depth, and the PECT is applied then in the magnetic saturation environment. The feasibility of the magnetic saturation PECT method for wall thinning detection in carbon steel piping is validated through numerical simulations. Firstly, the simulated polarization approach is adopted for the calculation of the static magnetic field distribution generated by the electromagnetic magnet, then the material permeability distribution is predicted according to the B-H curve of the targeted material. Finally the efficient PECT forward simulation tool is updated for the carbon steel based on the A_r (reduced A) method and the Fourier series strategy to validate the wall thinning detection in carbon steel material.