CASE EXAMPLE: PROBLEM SOLVING IN A QC CIRCLE USING SOME OF THE SEVEN TOOLS (HAMANAKO DENSO)
The basic reason for dealing with stratification is that it enables an effective causal analysis to be carried out and so improves the design of effective prevention methods. The case was published in 1984 in Quality Control Circles at Work—cases from Japan’s manufacturing and service sectors.
PREVENTING BREAKAGE IN V COILS:
Full participation as the first step in reducing defects
Parts Manager, 1st Production Section
Editor’s introduction:this QC circle is made up primarily of housewives who approach their circle activities in the spirit of brightening and enlivening their work, an important factor when one must manage both a home and a job. The company is sited near the birthplace of Sakichi Toyoda. In fact, the circle meetings are held in the house where he was born and to pay respect to his dying exhortation to ‘strive to learn and create and stay ahead of the times’. The three lines of their QC circle motto start with the three syllables of his given name:
SAra ni hatten (further development)
KItaeyo tagai ni (mutual improvement)
CHIe to doryoku de (with wisdom and effort)
The following account of their activities concerns the use of special equipment for winding automobile regular coils. Responding to a zero-defects policy at the company, the entire group set out to reduce the rate of defects from 0.2% to 0.02%. To see this difficult project through to completion, the leader applied the whole range of QC techniques and obtained co-operation from the company staff as well as the full QC circle. Patient data collection and analysis bore fruit and after six months, the target was more than achieved.
The report below covers all the necessary information about reducing defects in a machine processing step but, doubtless due to space limitations, it is less detailed than one would like in describing the housewife-dominated membership of the circle and explaining how the improvements were carried out.
Our QC circle is engaged in making one of the important parts of an automobile: we wind regulator coils. Stimulated by the catch-phrase zero major defects, it is decided to tackle the problem of breaks in these V coils.
(b) Process and our circle
· Our process consists of machine-winding the coil, wrapping the lead wire around the terminal, soldering it to the terminal, checking the resistance and visual appearance and delivering the coil to the next process.
· I am the only male in this 12- member circle.
· Nine of the women are housewives. The housewives’ average age is 38 and they have an average of two children each.
Fig: Regular coil winding. (Source: Asian Productivity Organization, 1984)
The QC circle got off to a difficult start, with only 50% attendance at the weekly after work meetings. The low attendance was discussed during the noon breaks and members gave such reasons as, ‘It makes people late in fixing meals for their families’ and Transportation home afterwards is a problem. As a result, we decided to:
1. Hold the meetings on Mondays, so that members could make their dinner preparations the day before (Sunday).
2. Give everybody a lift home afterwards.