基于嵌套问题的半圆轴瓦单元化装箱设计与容器选择

Unit Load Design and Container Selection for Half-bearing Packing Based on the Nesting Problem

针对工厂不规则形状工件单元化装箱与搬运的实际需要,以汽车与发动机行业常见的内凹形状的半圆轴瓦为代表,研究它的单元化装箱和最终标准容器的选择,提出半圆轴瓦等同件装箱过程中的特殊嵌套问题。这一嵌套问题不同于常见的平面下料嵌套问题,是将三维物体简化为二维问题来考虑,既有嵌套,也有装箱。分析嵌套柱形成的几何关系,将嵌套柱看作长度随嵌入轴瓦数量变化的特殊矩形,给出它的长宽表达式;研究了所形成嵌套柱的变长装箱问题,提出采用托盘装箱问题中可行的单块法与两块法来处理。考虑满足装箱平面利用率最高的情况下,和符合重量、搬运等实际目标要求,经160种轴瓦实际数据的编程计算,找到最优的嵌套装箱方式和最合适的装箱容器。结果分析与讨论表明方法可靠有效。

On the requirement of loading work pieces with irregular shapes into unit load for handling and transport in and/or between factories,the concave shaped half-bearing commonly found in automotive and engine industries is chosen as an example to examine their packing unitization and the selection of standard containers.The packing of identical half-bearing items is considered as a special nesting problem,which different from the nesting problem widely in planar material cutting stock.It simplifies the three dimensional items as a planar problem with both nesting and packing.The geometry of nesting column is proposed,it is treated as a rectangle with variable length which depends on the number of half bearing nested,and the length and width expressions of the nesting column are conducted.The loading process and pattern of these length-variable nesting columns is analyzed by using the feasible one-block and two-block loading pattern of the Pallet Loading Problem.With the objective of maximizing the area usage of container footprint,and satisfying the practical weight and handling constraints,the optimal loading patterns and their container are found by the calculation of 160 kinds of half-bearings.The analysis and discussion of the calculation results justify the reliability and effectiveness.