Under the operating load, the fabrication hydraulic torque converter could be regarded as a rotating pressure vessel. It will dilate like a balloon as a result of the centrifugal force and fluid pressure. The magnitude of deformation affects the performance of fabrication hydraulic torque converter and its connection with adjacent parts. Based on the three dimensional measuring machine and platform UG and Gambit, the frame model of ballooning deformation is established and simplified. Based on modern computational fluid dynamics theory, the simulation software FLUENT, MSC.Partran and MSC.Nastran are employed to make simulation prediction for the ballooning deformation. The results of the simulation are checked out through the experiments. The experimental results show that the calculation and experiment results are coherent. The increase of axial displacement has a linear relation with the rise of fluid pressure. The largest stress occurs near the intersect of the shell and working face. The largest strain takes place at the outlet of the pump and inlet of the turbine.