To improve the pressure-bearing capacity, a novel high-pressure die with cemented carbide as the first layer of supporting ring was designed. The novel high-pressure die increases the ultimate load-bearing capacity of the high-pressure die by increasing the pretension of the tungsten carbide cylinder. As the volume of the cemented carbide increases, the difficulty of manufacturing increases, therefore, to reduce the manufacturing difficulty of the cemented carbide supporting ring and reduce the shear stress of the supporting ring, the cemented carbide supporting ring is splited. And through reasonable derivation calculations, the calculation formula suitable for the optimal interference amount of the high-pressure die is obtained. The numerical analysis results show that: when a pressure of 6.2 GPa is applied on the inner wall of the tungsten carbide cylinder, high-pressure die mold that uses cemented carbide as the first layer of support ring (hereinafter referred to as double-layered cemented carbide novel high-pressure die) is lower than the ordinary high-pressure die in term of circumferential stress by 93.34%. In terms of von Mises stress by 21.4%, and term of maximum shear stress by 21.37%. The three principal stress images of the two molds are drawn, which proved that the double-layered hard alloy novel high-pressure die can fully exert the performance of the material and can withstand greater pressure.

In this paper, a model to simulate the dynamic behavior of the toroidal drive is developed. The three-dimensional dynamic model includes all six rigid body motions of the stator, worm, rotor and the planets. Using the model, the natural frequencies and vibration modes of the drive system are investigated. The vibration modes are classified into single modes and coupled modes. The single modes include planet mode, worm mode and stator mode. The vibration and frequency characteristics of different modes are obtained. The relation between modes and half cone angle of the planet tooth is discussed. The relation between vibrations and bearing stiffness is also discussed. When the bearing stiffness is about 10 times of the mesh stiffness, some vibration displacements of the drive system are quite small and can be neglected. Meanwhile, the dynamic equations for the drive system can be simplified.