| Aeroengine is a product of highly sophisticated technology combining multipledisciplines and fields,and it has the characteristics of complex structure,harsh working environment,high assembly difficulty,etc.The high-pressure compressor is the core component of the aero engine.The assembly quality of the core machine rotor directly determines the working efficiency of the whole machine and various performance parameters.In order to improve the current assembly methods such as manual trial and error and repair based on experience,it is very important to deeply study the assembly mechanism,optimize the assembly process parameters,and then realize the positive design of the assembly process.This paper aims at the typical rabbet and bolt connection structure of aeroengine rotor.First of all,In-depth analysis the characteristics of the interference fit of the rotor rabbet joint structure and the assembly process mechanism of the temperature difference method,and to complete the optimization of the key process parameters of the rotor assembly and the optimal design of the rabbet joint structure.Then,based on the assembly process of flange bolt rotor bolt group,a uniform pressure preload assembly process method is proposed and the positive design of assembly process parameters is completed.At last,designed the rotor simulation test piece and completed the pre-tensioned uniform pressure preload assembly process verification test for the assembly characteristics of the low-pressure rotor of aero engine.The main research contents of this paper are as follows:Based on the ABAQUS fully transient thermal-mechanical simulation technology,the hot-fitting process simulation model of the rotor interference rabbet joint structure was established.Analyze the characteristics of the rotor connection structure and complete the rotor assembly process mechanism research,and the assembly process parameters that have a prominent influence on the rotor assembly quality are determined.Establish the finite element analysis model,to improve the quality of rotor assembly,further optimization and analysis of the two parameters of the heating temperature of the hot pack and the interference fit of the rabbet joint structure,and obtained the optimal solution and the related influence law.A rabbet joint structure with transition chamfer is proposed.And comparative analysis obtained the degree of influence of this structure on rotor assembly performance.For the typical rabbet and bolt connection structure,carrying out bolting group tightening process research and proposing a uniform pressure preloading assembly process method.From micro to macro,and from single bolt to bolt group,the effect of uniform pressure preload on rotor assembly mechanical properties is analyzed in detail.Combining the theory of elastic mechanics and the principle of maximizing the centering accuracy of the rabbet joint structure,the positive design of the process parameters of the uniform preload force is completed.At last,analyze and get the optimal tightening process of bolt assembly:the tightening sequence is the cross torque torque angle control two-step tightening process.Carrying out verification test of assembly process of aeroengine simulated rotor.Study the principle and method of bolt preload and bolt joint surface pressure test.And on this basis,According to the horizontal assembly characteristics of the low-pressure turbine shaft-disk hub connection structure,the uniform pressure preload assembly process test by the process bolt pretensioning form is completed.It was found that under the effect of uniform pressure preloading process,the preload of the bolt group decreased by 56.34%.Prove that the uniform pressure preload process can effectively improve the rotor assembly quality. |
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