Journal: Emerald
Author: Andrew Lee-Mortimer
Abstract:
Purpose– Aims to detail
the on-going implementation of lean manufacturing at a UK-based electronic
product-manufacturing operation. Design/methodology/approach– Describes how and
why a manufacturing operation, which had already seen major improvements that
had made ita highly regarded plant, is adopting lean manufacturing as part of a
manufacturing survival strategy. It also looks at some of the main Lean
projects undertaken, the major benefits gained and the key lesson learned.
Findings– While the operation’s highly effective continuous improvement
programme had delivered a major culture change along with significant OEE and
quality improvements, the introduction of lean manufacturing highlighted that
this had been achieved at the cost of creating a number of “islands of
excellence”; resulting in high levels of WIP and long lead times. The
implementation of lean manufacturing is now enabling this electronic products
manufacturer to build on its excellent foundation of continuous improvement,
and start the process of moving away from batch and queue to creating flow
through the whole plant; reducing WIP and lead time, and improving
productivity, without compromising previous gains. Originality/value– Brings to
the attention of managers how it often takes the wider focus offered by lean
manufacturing to discover the hidden waste that can reside even in operations
that appear to be very effective. Confirms the importance of moving from a
batch and queue mentality to process flow, and the productivity benefits that
can be gained, but also highlights that even well-organised businesses are
liable to suffer pain when implementing lean, especially with respect to
introducing flow and eliminating WIP, which has to be worked through.
Introduction:
Despite all the “talk” of
lean manufacturing, it is obvious that many manufacturers have yet to grasp the
full benefits of this philosophy. In particular, the focus at many plants
producing and assembling electronic products, which are often dominated by large
capital equipment and areas of automation, has tended to remain fixed on OEE,
high quality and on-time delivery, and they have continued to be driven by an
in-trenched and out dated batch and queue mentality. However, there are those
that have been quicker to catch on to the lean manufacturing wave, and who now
accept it as a key part of their strategy for long-term manufacturing survival.
With its focus on removing the waste in current systems, concentrating on
adding value that customer pay for and improving product flow, to increase
productivity and reduce lead times, lean is seen as representing a clear way
forward for all of those looking to effectively face the increasing challenge
posed by the low cost economies. One plant that exemplifies the required
survival attitude and approach is Siemens Standard Drives based in Congleton,
UK. Part of Siemens Automation & Drives, the operation employs
approximately 420 people, and is now responsible for the design, manufacture
and customer support of a range of electronic drives up to 15 kW. A few years
ago, the operation realised that despite having worked hard to become one of
the best production facilities in its sector, meeting all key quality and
delivery targets, and being recognised as such, more was needed if it was to
continue to compete in a global economy. Embarking on a fully integrated lean
manufacturing programme, Congleton ’immediate gain was an insight into how much
“hidden” waste, and potential for productivity improvement, there was within
its facility. Accepting the challenge, the company has subsequently tackled the
new improvement programme with the same workforce focused approach that had
already achieved so much. And, although not all the changes have gone to
strictly to plan, the programme has not only delivered major performance gains,
in terms of reducing lead time and improving productivity, but it has also
delivered some crucial lessons that the operation is now applying to enhance
its future lean developments.
A
shocking discovery:
However, another key sign
of the operation’s development is that even while it was winning all these
plaudits, the management team had already accepted that continuing what it was
doing well, in terms of CIP, was not enough to deliver the future improvements required.
The mission for the site has long been to become the “proven choice for
manufacturing” within the group. But, the growing realisation was that as well
as improving its competitiveness against the other Siemens electronic
manufacturing plants across Europe, who would be more than willing to take its
products, the UK operation was going to have to compete against the
increasingly impressive production facilities in China to which production
could potentially be outsourced. Therefore, to deliver the extended year on
year productivity improvements that were seen as essential to ensure long-term
survival, the management started to look around for an approach that would
build on the existing and on-going change initiatives, and provide the next
“leap forward”. What was found, as the solution, was lean manufacturing.
Building
on strengths:
However, while others
remain in the dark, Congleton’s management team used the mapping process as a
key tool in helping to gain a clear understanding of the plant’s situation.
This has lead to the subsequent development of a very structured and
strategically integrated approach to the full deployment of lean throughout the
site. A lean steering team, involving managers from across the operation, now
guides the overall programme, and has helped gain buy-in from the different
departments. Targets have been set that are closely aligned with, and are being
be measured against clear business goals. From the start the aim of the lean
programme has been to slash WIP levels, reduce finished stock levels in
Germany, dramatically cut lead times, to just a few days, and increase
productivity.
The manufacturing value
stream for the Congleton facility comprises of four core processes; surface
mount, board assembly and wave solder, board test and final mechanical
assembly, test and packaging. The mapping exercise highlighted the third stage
– the testing of the PCB boards – as a major bottleneck, and therefore, the
first lean project undertaken was aimed at making more capacity available, and
so ensures more consistent delivery to the next process. As Webster, reports,
the operation was struggling to get boards through testing and into the final
assembly area and it was clear from early analysis that the test fixture
changeover practices were extremely “wasteful”. To help tackle this issue, the
manufacturing advisory service, was brought to organise and run a two-day SMED
workshop for a team of 30 employees from the test area. Initial diagnostics
undertaken by the workshop confirmed the problem. In fact, looking at one
“pilot” testing fixture it was found that due to a number of factors; such as
lack of clearly defined responsibility for changeover elements, no changeover
standard operation, different changeover techniques used between the shifts,
and test equipment not running for the full duration of the changeover, that
the average change over time of around ten-minutes was at least 50 per cent
higher than needed to be. And with around 2,600 changeovers completed per year,
for this one type of fixture, per machine, even this equated to a huge lost
production opportunity. Based on these findings, the workshop guided the team
through a “live” SMED project on the pilot fixture.
Balancing the workload:
Having very successfully
resolved the bottleneck issue within the test area, the operation has since
embarked on its second major project. As a result, the final assembly, test and
packing area for its core product range, which as the last process in the value
stream should dictate the pull rate of the production flow, has now undergone a
complete “lean” overhaul. However, it was during this project that the
operation learnt first-hand about the pain that can often accompany a major lean development.
Exposing
problems:
All our lean activity, up
until this point, and especially the SMED work within the tester area, had
delivered important productivity and lead time gains, without any real pain.
However, creating the new final assembly cells was the first time that we had
aimed for single piece flow and the elimination of “safety” WIP. The MAS
practitioners had warned us from day one that this would probably expose
problems that had been hidden by the high levels of WIP, but we had not really
taken this on board. But it was not long after the four new cells were
operational that the predictions came true and we started to encounter a
continual loss of production due to a range of previously unrecognised issues.
Lessons
learnt:
Nevertheless, the
introduction of the cells has proved another major eye-opener for the site, and
looking back there is also recognition that with a bit more foresight and
co-ordination some of the pain experienced could have been avoided. For
instance, the operation now realise that more could have been done to determine
the performance and availability of the test equipment beforehand, and so not
only anticipate the impact and potential losses, but put in measures sooner.
Equally, there should have been greater and wider awareness of the level of
equipment support that would be required within a single piece flow process,
which should have been better conveyed to the support technicians. Previously
it has been acceptable, if the engineers prioritised their work so that they
got down to the lines within a few hours. With the cells, not only is instant
support needed, but also problems have to be fully resolved not just fixed for
the short term
The introduction of the
cells was rushed and not everything was ready in terms of material supply,
standard operating procedures or operator training. In particular, it was
assumed that because the operators had all worked in the area for years they
would automatically know and understand all that was required.
Conclusion:
Crucially, this most
recent experience has not deflected the operation from its overall lean
programme. More projects are already being planned. These include moving
recently introduced PCB coating equipment into a physical position better
suited to value stream position, which is between PCB testing and the final
product assembly cells, and at the same time eliminating the existing WIP
storage at the end of the coating process. The aim will be to establish real
flow from testing, through coating and into the assembly cells, with the cells
requirement dictating the throughput. An even bigger challenge is on the
drawing books that could see the breakup of two of its core process islands,
the PCB assembly and the PCB test areas, and the creation of cells that will
manage the assembly, solder and test as a single piece flow, so further
eliminating the batch transfers that still exists.
However, two things are clear. Siemens
Congleton has already benefited greatly from its lean programme. Through its
lean focused CIP and the major projects completed, significant inroads have
been made in reducing internal lead times, removing non-value added activities
and increasing productivity. Second, the operation, management and operators
alike, are now far better prepared for the problems and pain that are bound to
be experienced when the next lean developments are implemented. As Webster
concludes, “The lessons learnt are being put to good effect in the planning we
are now undertaking for our next major Lean projects”.
