Overview

The way parts are presented to operators impacts both productivity and quality. Assembler time is expensive because operators work in series on the line, but materials handlers, on the other hand, work in parallel. The materials group is the pit crew to the assembler's race car driver, and should focus first on providing effective support to assembly and second on doing it efficiently. Regardless of what managers may believe about "non-value added" activities, the number of people handling and preparing parts is often increased in order to reduce the total amount of labor spent on assembly.

Parts should be presented to assemblers unpacked, within arm's reach, with their smallest dimensions facing out, and oriented for easy installation. Deliveries to the line should be at fixed intervals, in quantities matching the consumption rate, and in returnable containers with dividers or part-specific dunnage, to facilitate counting and prevent errors. The picking strategies of kitting and lineside supply should not be viewed as mutually exclusive but used in combination. When used, kitting should be for single product units. It should be done just before assembly, and into trays with kit-specific dunnage.

Single-piece presentation and water spiders are further techniques used in particular to allow assemblers of large products to pick parts without turning around in "washing machine" movements.

11.1. Scope and Purpose