| Summary: | Setup time reduction Is an essential activity used to prepare
the facility for just-in-time (JIT) manufacturing; the aim oZ
which Is to assist In meeting the desirable manufacturing
requirements of delivering low cost quality products on time.
(20) The Japanese have shown that setup reduction eliminates
the need for setup skills and producing In large or "economic"
lot sizes. (1 ) It is usually the case that preparation and
adjustments, which usually account for 95% of the setup time,
can be externalised or eliminated. (1)
The overall production process should be examined before setup
times are reduced on existing equipment. (2) Considerations
Include group technology, setup sequencing, dedicated machines
identifying bottlenecks (stated by OPT) and the 80/20 rule. A
training programme should be initiated where setup reduction
teams, consisting of production operators, setters, foremen
line supervisors and production engineers, are educated in JIT
manufacturing, the changing business environment and recording
and analysis methods. (31)
A theoretical approach to setup reduction has been formulated
by Shlgeo Shlngo. (1) During the preliminary stage Internal
and external setup are not distinguished, therefore this stage
involves a work/time study of the existing setup and activity
categorisation. From this, potential externallsatlon or
elimination of setup operations can be determined. The first
stage of setup reduction involves separating internal and
external operations. During this stage tooling organisation and
pre-preperation activities are converted to external
operations. The second stage of setup reduction involves
converting internal to external setup. A simple Pareto analysis
is conducted to determine time consuming activities, which are
then tackled first. This stage includes equipment modification,
standardisation of procedures, parallel operations and
elimination of adjustments. The third stage involves
streamlining setup operations by improving operations and
initiating setup practise sessions. All ideas should be
documented and implemented immediately.
Setups should be kept in mind when buying new equipment,
however it is usually more beneficial to modify existing
equipment in-house. (4) Setup reduction costs are low at first
for large time reductions, but costs become high yielding small
returns during the final stages of the programme. (31) It may
be beneficial to introduce an incentive scheme where members of
setup teams receive recognition and a financial reward for
implemented ideas. (34)
A setup reduction programme was implemented at Viro Looks, the
aim of which was to illustrate the theoretical approach to
setup reduction. Setups were reduced here on a transfer machine
by 67%, 60% time savings being achieved at low/no cost. A
survey was performed involving 18 leading JIT companies, where
it was found that the majority (14 companies) have initiated a
setup reduction programme. However many of these companies have
only limited experience in setup reduction and, according to
the survey, require 4-6 years to reach the final stages of
setup reduction.
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