Structural Optimization And Application Of Shot Peening Equipment Of Engine Blade

Improving the strength of engine blade methods are mainly shot peening, shot blasting, high pressure water jet surface strengthening and ultrasonic surface strengthening. They all have their advantages rely on their own characteristics. The shot peening process has the advantages of high shot peening intensity, good shot peening quality and low shot peening cost in strengthening engine blade’s surface. It has been favored by domestic and foreign scholars. The engine blade shot peening device has been widely used in improving blade’s quality, repairing blade and protecting blade. But the problem is also can’t be ignored. The general shot peening device is difficult to complete the shot peening of complex curved whole surface. Improving the effect of shot peening, reducing the production cost, and developing the new device of shot peening have become an urgent problem.This paper optimizes the key parts of the shot peening device and designs the nozzle, the engine blade fixture, the shot peening table and the wheel drive mechanism to achieve the full surface shot peening of the blade. This paper applies Solid works software to establish three-dimensional solid model of the engine blade’s shot peening device. Finite element analysis software is used to optimize the above key parts to realize the cost minimization and the surface strengthening effect of the blade.EDEM software has been used to analyze the projectiles’ velocity in nozzles’ outlet and research the velocity of different types of nozzle and different diameters of the projectiles. The simulated results show that: 0.3mm projectiles’ velocity in venture nozzles’ outlets are closest to the optimization objective values. Based on optimal peening velocity, this paper gets movement rule among the nozzles’ diameter, length, diffusion angle by using EDEM software, and gets the optimal nozzles’ diameter range are 6.4 ~ 9.5mm, the optimal nozzles’ length range are 70 ~ 86 mm, the optimal nozzles’ diffusion angle range are 7° ~ 9°. Orthogonal experimental technology has been used to find the relationship between projectiles peening velocity and nozzles’ diameter, length, diffusion angle. The optimal solution is that the nozzles’ length are 70 mm, the nozzles’ diameter are 9.5mm, nozzles’ spread angle are 8 °.Workbench software has been used to simulate general ball type and improved planetary shot peening table’s stress, strain, and total deformation. Simulation results show that: under the same load condition, the multi point support of the planetary shot peening table can effectively disperse the load. The maximum stress and the maximum strain value are decreased, and the life of the bench is improved compared with stress concentration of ball table. This paper checks the optimal gear mechanism’s tooth contact fatigue strength and tooth root bending fatigue strength, the checking results shows that: the strength of the gear mechanism meets the requirements. The improved planetary bench saves the time of adjusting the position of the blade. The improved planetary bench achieves the effect of multi angle and full surface shot peening in a single set-up and effectively improves the shot peening efficiency.This paper optimizes the structure of main parts of the circulating mechanism’s elevator. Through intensity check and analysis of Workbench software, the paper gets the optimized spindle’s maximum stress value is 310.8MPa, the maximum strain value is 1.6×10-3 when the diameter of the spindle is 53 mm and the optimized pulley’s maximum stress value is 305.2MPa, the maximum strain value is 1.5×10-3 when the thickness of the belt wheel is 11 mm. The check result shows the optimized spindle and pulley meet the requirements of the yield limit of materials. Optimization of the above structure satisfies the operation safety, reduces the weight of the parts and reduces the manufacturing cost.This paper carries out the applied experiment of the optimized shot peening device. 45 steel blades which are sprayed by optimization shot peening device are used to observe the super depth, measure hardness and measure residual stress. The three-dimensional morphology, mechanical properties and residual stress of blades have been compared. The compared results show that the optimized shot peening device has obvious effect on the surface strengthening of the engine blade. The hardness is greatly improved, the roughness of the parts is decreased and tended to be the same, and the residual stress is increased. The full surface shot peening of the engine blade is achieved by the optimized shot peening device.