QMT Features: September 2010
Electrifying quality
A Six Sigma initiative and investment in automation and training delivers impressive manufacturing improvements at PP Electrical Systems

A UK-based manufacturer of electrical and electronic assemblies has attained manufacturing quality levels of 99.97% following the installation of fully automated, custom designed wire processing machinery at its factory in the West Midlands.

A gradual, phased implementation of automated production machines over the last 10 years – coupled with PP Electrical Systems’ (PPES) own successful culture change programme and continuous improvement initiatives – have resulted in quality levels increasing from 98% in 2007 to 99.97% in 2010.

“Whilst most manufacturing companies would regard 98 per cent quality as being world class, at PPES we recognised that we needed to achieve in excess of 99 per cent if we were to satisfy our customers and reduce costs by revealing more of our Hidden Factory. The extra effort we’ve had to put in over the last decade in improving our quality to such a high level has been a struggle at times, but the rewards far outweigh this,” states David Fox, chairman and CEO of PPES.

He continues: “This 1.97 per cent quality improvement from 1998 to 2010 may not seem all that much to some people, but the cost savings relating to this have gone straight to our bottom line. We’ve been able to uncover many of our hidden factory costs, particularly re-work and re-testing. Furthermore, we’ve saved money by not having to send our service engineers half way around the world to a customer only to find out that the problem with our control panel was down to something minor such as a faulty cable connection, which could and should have been detected at our factory before leaving the gates.”

Investing in people & automation
Since 2000, PPES has seen its revenues (and profits) more than treble, with revenues set to increase again in 2010. The foundation for this success, says Fox, is not only from introducing automation to the factory, but also from investing a considerable amount of time and effort in training employees and going through the pains of a comprehensive, but ultimately rewarding culture change programme.

Also pivotal to the company’s success was the setting up of PP’s own Training Excellence School (now a separate division known as PP Business Improvement) in 2000. “The primary objectives of this school were to provide structured learning facilities to all employees, as well as act as a catalyst in changing peoples’ attitudes towards change throughout the business, including the gradual transformation from traditional manual wire processing, which represented a relatively large proportion of panel assembly – to semi-automatic and fully automated production machines.”
This phased programme of automation was seen by PP as a key part of improving the company’s quality levels, by removing manual errors from the assembly process and ensuring that all products were manufactured ‘right first time’, with zero defects, minimal rework and retesting. As Fox puts it: “An important part of this transformation process was to automate our wire stripping and crimping process, which is how our partnership with Cablespeed Ltd came about.”

“Cablespeed introduced us to one of its branded manufacturers, Artos, a leading manufacturer of wire processing machines based in the US. What we liked about Artos was its understanding of Six Sigma and how its wire processing machines could help us eliminate process variation in support of our Six Sigma quality initiative. By implementing Artos machines we’ve been able to achieve repeatability in production, which has enabled us to attain close to 100 per cent quality,” he adds.
12 years ago, there were no automated machines at PPES.

With Cablespeed’s help, a phased implementation of Artos machinery began with the introduction of bench-mounted wire ferruling machines. At that time, it was felt that the operators did not have much experience of automation and so initially moving from manual to fully automated machinery would be too large a step change for many of these people.

In 2005, phase two began with the implementation of semi-automatic wire stripping and crimping machines. A variety of semi-automatic machines were introduced. The operator still had to manually feed the wire into a slot on the machine and then hold the wire in position, but the rest of the stripping and crimping process was automated. A total of six bench machines in three different sizes were installed at this time.

Step change in quality improvements
The next stage involved the implementation of fully automatic wire stripping and crimping machines. These machines drew wire stock from barrels that were positioned adjacent to the machine. These machines also had the ability to mark legends onto the wire, which helped the fitters downstream to identify each wire and to see where and how the wire needed to be assembled in the electrical assembly. This was a key step change for PPES because it meant that quality levels could be improved significantly. 

The next and latest phase of the automation programme began in 2007 when PPES decided to convert to fully automatic wire stripping and crimping machines. “The new Artos MTX 10 machines, of which there are two [one is a standby machine] can produce ferrules, as well as open and closed barrel type crimps,” explains Fox.
The MTX Series 10 machine is the latest member of the Artos family of fully programmable, multi-task wire processing machines. By extending each swing arm on the base model, Artos has made room for three processing stations on each side of the processing table, six in total. This enables a total of six possible processing steps on each end of the wire, a significant achievement in terms of automated wire processing.

The machine can therefore handle two types of ferrule and four other types (open or U) and closed barrel type crimps. The wire from the stock barrels is automatically cut to length, marked, then ferrules are added and/or crimps – all completed without the operator having to change the set up of the machine. Everything is programmable and every axis is servo-driven. The machine also incorporates crimp force monitoring.”

Previously, the operator would take two or three crimped wires and use a crimp height-measuring gauge to check the pull force required to pull out the crimp. However, this method did not 100 per cent guarantee the quality. The new Artos MTX10 automatically checks each crimp against a set tolerance defined by the factory’s Six Sigma system, highlighting any quality problems or defects.”
Fox concludes: “This phased implementation of automation means that we’ve been able to increase our quality levels from 98 to 99.97 per cent since 2007, with Cablespeed and the Artos machine making very valuable contributions towards this improvement. The wire processing is now right first time and we’ve seen massive savings by eliminating rework and retesting. Process variance has also reduced significantly in support of our Six Sigma initiatives.”l
email: foxd@power-panels.co.uk

You can now view all QMT Magazine issues on your favourite tablet or smart phone.
Download the free Quality Manufacturing Today App from the Apple iTunes App Store or from QMT Magazine on Google Play.

Rob Tremain Photographer
Click above to see full page display and links to QMT articles.
Bowers logo
Hexagon Logo 2
Mitutoyo logo