Research on the design of non-destructive assembly and disassembly interference fit for aircraft engines.

Abstract

The temperature difference method is used for the assembly and disassembly of cylindrical interference fit in aircraft engines, which is prone to causing scratches on the contact surfaces. To improve maintainability, this study optimized the design of a conical interference fit with an oil groove, which not only maintains torque transmission capability comparable to that of the prototype but also achieves non-destructive assembly and disassembly. The similarity criteria for the torque transmission capacity of interference fit and the design requirements for taper were derived, forming a design methodology for the conical interference fit. By reducing the distortion of the similarity criterion, an optimized conical interference fit with an oil groove and a taper of 1:15 was designed for aircraft engines. Based on finite element analysis, the torque transmission capability prediction coefficient between the optimized structure and the prototype was 0.972, demonstrating that the optimized structure can effectively represent the torque transmission capability of the prototype. Hydraulic assembly and disassembly, as well as torque transmission tests, were conducted on conical interference fit specimens with oil grooves. The theoretical and test results of torque transmission capability were compared, and the mating surfaces were analyzed for scratches after torsional loading and disassembly, thereby verifying the validity of the non-destructive assembly and disassembly interference fit design. The design method has engineering applicability and offers a reference for the structural optimization and analysis of interference fit.