Figure 1: The output of production resources must be
as predicable as possible.
Figure 1 highlights the importance of a capable and reliable
information system (FR-P11). An information system allows
the gathering and storing of data, its transformation into
information, and the transfer of information from sender to
receiver. Thus, the information system supports the achievement
of predictable output from all resources of the manufacturing
system by providing timely, reliable, and relevant information.
The decomposition of FR-P12, “Ensure predictable equipment
output,” and its corresponding DP stresses that equipment
must be designed for serviceability (FR-P121) to achieve successful
maintenance (FR-P122). Further details about equipment maintenance
can be found in the literature of total productive maintenance
[e.g. Nakajima, 1989].
There are numerous norms and guidelines for the design of
work systems from ergonomic to psychological aspects to achieve
stable operator output (FR-P13) [e.g. ReFa, 1993; Grote et
al., 2000]. Quality and cost aspects of standard work procedures
are covered by DP-Q122 for stable quality output and by the
decomposition of the direct labor branch (DP-D1). Three requirements
are defined to achieve stable time output from operators as
shown in Figure 1: reducing variation of task completion time
(FR-P131) by defining standard work methods (DP-P131); ensuring
that operators are available when tasks need to be performed
(FR-P132); and avoiding production disruptions due to worker
allowances (FR-P133) by mutual relief (DP-P133). Cross training
also increases operators’ competence and flexibility and helps
to improve quality and reduce costs.
The performance of standard work influences the availability
and delivery of material. Thus, DP-P13 affects FR-P14 “Ensure
material availability” (see arrow between DP-P13 and FR-P14
in Figure 1). FR-P14 requires parts to be available when demanded
(FR-P141) and to ensure proper timing of part arrival at downstream
processes (FR-P142). Standard Work In Process (SWIP) between
subsystems (DP-P141) serves as a buffer against production
uncertainties and transportation delays. Low volume manufacturing
may require a different strategy to ensure part availability,
since it might not be possible to keep standard amounts of
material between the manufacturing processes.