In this present study, an improved theoretical model is developed to analyze the manufacturing process of a mechanically lined corrosion resistant alloy (CRA) pipe by a hydraulic expansion. The formula of the relationship between the applied hydraulic pressure and the resulting residual interfacial pressure between the inner liner and outer pipes for the mechanically lined CRA pipe is obtained. The minimum and maximum critical hydraulic pressures are also investigated and an effective forming pressure ranges is found. A 2D axisymmetric finite-element model is built in abaqus™ to simulate the mechanically lined CRA pipe during the hydraulic expansion manufacturing process. The analytical and simulation results are compared with the experimental results found in the literature, which reveals that the theoretically calculated residual contact pressure and the finite-element computed results are in good accord with the experimental results. Therefore, the models built in this paper can be applied in actual manufacturing process of mechanically lined CRA pipes.