Improving Business Performance With Lean, Second Edition

APPENDIX

The Effect of Variation on Kanban Systems

This appendix demonstrates the effect of variation in replenishment times and material consumption rates on the number of kanban cards required to sustain production and, therefore, on the maximum amount of inventory needed at the point of use and its resupply. The demonstration is provided by a spreadsheet model, which simulates the dynamics of a kanban replenishment system with varying degrees of uncertainty. The spreadsheet allows for a hands-on experience that helps to develop intuition about kanban dynamics. While our intent is primarily to illustrate the effect of uncertainty, this model could also be used to estimate the cards required in an actual process. The spreadsheet model can be ...