The operation of a conveyor system supplying unit build assemblies

Abstract

The trials of coping with negative aspects of behaviour such as absenteeism, lateness, and labour turnover have persuaded many companies to abandon the assembly line mode of mass production. Job enlargement exercises have demonstrated the benefits of assigning the building of a complete unit to one operator, thereby eliminating the co-ordination problems associated with dependent stages, but unless accompanied by a radical reappraisal of methods this may lead to a large increase in standard assembly time per unit.

One development is the introduction of discrete kits of major parts, supplied on separate trays by continuous overhead conveyor to individuals who remove them as required. The success of this materials handling system depends upon the provision of a high feed rate that prevents operators towards the far end of the supply line from being unduly starved of work. A digital simulation model has been developed, sampling from a realistic service-time distribution, to estimate the maximum output that capital equipment of given physical characteristics can economically sustain. The description has been extended to show the impact of supplying separate model lines from a common track, and used to determine whether this is a viable policy for an actual factory situation