Taguchi Compliance Graphic Concept
Taguchi Compliance Graphic consists on a method created by the Japanese statistic Genichi Taguchi and places the emphasis on the comparative analysis of the distribution variations of a certain product or piece as to its specific techniques. Beyond allowing the produced pieces compliance analysis as to specifications, this method allows to identify and avoid deviations and still transmit statistic process control principles for manufacturing, logistic and other functions.
Taguchi’s researches lead him to conclude that is preferable to produce pieces whose distribution be centered in the specification-target, instead of pieces whose distributions is not centered in the target. Such is due in big part to the accumulation of deviations: if a certain size of a piece is at the superior limit of its specifications and the other at the inferior limit, the combined variation of specifications can forbid that the pieces fit together. One of the Taguchi Compliance Graphic goals is, this way, to assure that the distribution of each piece is made in a way that the quantity of accumulation situations be minimized being, for this, extremely useful in cases in which are manufactured different pieces to be assembled on only one product.
Implementation Instructions:
- Withdraw a representative sample of pieces from the production line (or from the ones supplied by the suppliers); at least should be 30 pieces, but preferably more.
- Measure the pieces’ characteristics (weight, length and other); each measured characteristic originates a different graphic.
- Build an absolute distribution chart and, based on this, a bar graphic on which on the horizontal axis are placed the measures and on the vertical axis the correspondent frequencies.
- In the same graphic, to draw a vertical line corresponds to the specification-target or, in the case that limits for the specifications are defined, a representative line of the specification-target.
