Multi-wedge Cross Wedge Rolling (MCWR) is an advanced technology in forming long axial parts, and it does not have the disadvantages of Single-wedge Cross Wedge Rolling (SCWR).However, it is extremely important to realize the regularity of the displacement on the end-section of the rolled parts in MCWR due to the complexity of its forming mechanism. In this paper, based on the method of the displacement on the end-section of the rolled parts in SCWR, the rules of the displacement on the end-section of a typical rolled part in MCWR were investigated theoretically, and the curve on the end -section of the rolled part in MCWR were analyzed.Based on the curve, the regularity of metal flowing and the characteristic of forming for the typical rolled part in each phase by MCWR were analyzed. It is of high value in studying the forming mechanism and designing mould and technics in MCWR.

Based on the principle that in the deformation zone the length of bore plain wire does not change, a mathematical model of the prefabricated hole flange-forming of unequal diameter tee pipe is established, for the difficult problem of the flange-forming prefabricated hole size design for tee pipe. To solve the mathematical model, a numerical method and a software system for The solution of the mathematical model is established. In order to verify the reliability of this article to build the mathematical model and its solution, taking engineering for example, apply the method of finite element simulation to verify the mathematical model and the solving system, and the results show that the mathematical model constructed in this paper can relatively accurately make calculation of prefabricated hole size of flange-forming of unequal diameter tee pipe.

Based on the principle of the length unchanged and the principle of the area unchanged in the deformation zone, a mathematical model of the flange-forming prefabricated hole of hemispherical shell parts is established, for the difficult problem of designing the flange-forming prefabricated hole size for hemispherical shell parts. To solve the mathematical model, a numerical method and a software system for the solution of the mathematical model is established. The feasibility of the mathematical model and solving method is demonstrated by the simulation of the typical flange-forming of Hemispherical Shell Parts.

Abstract. The key problem for flanging forming of square tributary junction on spherical shell is to determine the shape and sizes of prefabricated hole. In order to investigate precise shape and sizes of the prefabricated hole, an optimized design model was established. The flanging forming process was simulated using the software of FE-simulation and the target function for optimized design was calculated based on results of the simulations. In order to increase the convergence rate of the optimized design, a mathematical model of prefabricated hole for flanging forming on spherical shell was established, the results were used as initial values for optimized design. To verify its accuracy, the optimized design was carried out on a typical flanging forming of square tributary junction on spherical shell. The results of the optimized design meet the technological requirements.

For the difficulty of calculating the size of the Pre-Manufactured hole of flanging, the formula was derived by using the theory of equal line length and the theory of equal area. And the formula was verified by finite element simulation. Due to theoretical formula has certain error, the optimal design method based on interpolation was put forward and optimization design the size of the Pre-Manufactured hole of flanging. Engineering example shows that this optimization design method is accuracy and convergence speed, and it can quickly calculate the the size of the Pre-Manufactured hole of flanging.