Abstract: Maintenance disassembly sequence planning is an important facet of maintainability design. This article presents a thorough study of the product disassembly modeling method for maintainability design. Civil aircraft products are divided into two categories of component-modules and joint-parts, and a component-joint graph is developed by describing the relationship between them with an incidence matrix. The disassembly sequence planning method of civil aircraft products is provided in two steps. First, the disassembly direction of component-modules is determined by an interference matrix, and the disassembly sequence planning method of component-modules is proposed based on an ordered search by taking the minimum disassembly expense as the optimization objective. Second, by taking into consideration the disassembly order of joint-parts, the whole disassembly sequence planning method is proposed based on the genetic algorithm of gene pair crossover and mutation by taking the minimum tool change time as the optimization objective. Finally, an application instance is presented of the disassembly sequence of the nose landing gear system of a certain civil aircraft to illustrate the validity of this method.

Key words: maintainability design, disassembly sequence planning, component-joint graph, ordered search method, genetic algorithms