Meeting 100 per cent accuracy requirements with Poka Yoke

Assembly Automation

ISSN: 0144-5154

Article publication date: 7 August 2007

1593

Citation

(2007), "Meeting 100 per cent accuracy requirements with Poka Yoke", Assembly Automation, Vol. 27 No. 3. https://doi.org/10.1108/aa.2007.03327cab.004

Publisher

:

Emerald Group Publishing Limited

Copyright © 2007, Emerald Group Publishing Limited


Meeting 100 per cent accuracy requirements with Poka Yoke

Meeting 100 per cent accuracy requirements with Poka Yoke

Industrial Automation Ltd has helped Hi-Lex Cable System Co. Ltd meet its 100 per cent accuracy requirements on three of its transmission cable production lines with a purpose built series of machines (Figure 2). Hi-Lex manufactures tier-1 components for the automotive industry – for customers such as Ford, Volvo, Honda, Land Rover and Mitsubishi and is audited to the ISO/TS16949 quality standard.

Figure 2 One of the IAL stations installed at Hi-Lex Cable System Co. Ltd

Hi-Lex is part of the TSK Group (Hi- Lex Corporation) and the European HQ at Port Talbot, South Wales has been operating for over 6 years. In 2003, Hi- Lex won a phased contract from Ford to supply transmission cables for the Transit van, Volvo, Galaxy and the Mondeo. Keith Banfield, Process Development Manager at Hi-Lex comments, “With such a prestigious contract requiring 630,000 gear cables per annum, we needed a number of new, purpose-built, production lines. We determined that three lines would be needed: one for the Transit's manual transmission system and two for the European C/D class (EUCD) platforms for the cars – one line for manual transmission and one for automatic transmission.”

Keith wrote the specification requirements for the three lines and contacted a number of manufacturers to invite them to tender. The three lines would be awarded as one contract to the manufacturer that met a number of criteria based on cost, presentation, credentials and understanding of Hi- Lex's needs. Industrial Automation Ltd was one of the companies invited to tender because of its experience in providing bespoke solutions to manufacturers of automotive components. In addition, a number of engineers at Hi-Lex had worked with IAL previously and were happy to recommend them.

Keith comments, “IAL were finally selected to fulfil the contract because they met all the requirements, but in addition were forward-thinking enough to make suggestions over and above the brief – such as a proof-load indicator at one of the stations.”

One vital aspect of the brief was to provide an assembly automation solution that had 100 per cent accuracy built in. This is in order to comply with Hi-Lex's Poka Yoke quality systems. Poka Yoke is a Japanese term – Yokeru meaning “to avoid” and Poka meaning “inadvertent errors”. Error proofing is a manufacturing technique of preventing errors by designing the manufacturing process, equipment, and tools so that an operation literally cannot be performed incorrectly.

Another requirement of the contract was that the Hi-Lex team insisted on a face-to-face meeting with the IAL project manager at an early stage. Dave Nicholls of IAL comments, “In this age of communication, it is all too easy to manage the workflow of a project electronically; Hi-Lex's ethos of close collaboration, with like-minded people, ensures that we fully understand the customer's requirements. We believe this is the best approach to bespoke automation solutions where there may be a number of approaches that can be taken. Put simply, we `solve engineering problems' so can make suggestions to give added value and anticipate future issues or demands.”

IAL installed the three lines in summer 2005. The production process on each line is broken down between five stations – each staffed by one operative:

  1. 1.

    Ensure all “child” parts are present and in the correct position.

  2. 2.

    Ensure all abutments are affixed in the correct position and orientation. At both these stages, the machine will not function if anything is an amiss – and the operator will be given a visible warning.

  3. 3.

    This station performs a similar function to station 2 for another section of the cable but additionally performs a load test on the cable. IAL also implemented a pressure test system on the load test element itself – so that if pressure was lost, thereby rendering the test inaccurate, the operator would be aware and could rectify the pressure loss.

  4. 4.

    Key lengths of the final assembly are made, including checking that the end rods have the correct orientation.

  5. 5.

    The last element is a friction test station whilst the cable assembly is in its final configuration.

At each stage, safety of the cell is assured with light guards that will not allow the relevant action to be performed if it detects any intrusion by an operative.

Keith Banfield concludes, “Ford's own Q1 quality control system demands 100 per cent accuracy, so in order to comply with this, we needed to ensure that the IAL lines were indeed providing 100 per cent perfection by continuing to quality control check all the cable systems. We have now reached the stage where we are totally satisfied that we are achieving 100 per cent precision so will be able to achieve maximum capacity as the full requirements of the contract come on-stream. We are able to offer customers an unrivalled transmission system because of the uniqueness of the conduit and abutments. The result is that automotive companies are able to design their transmission systems in such a way that gives them more flexibility regarding the whole driving experience.”

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