Page 178 - The Toyota Way Fieldbook
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154                       THE TOYOTA WAY FIELDBOOK


            The first pass of leveling will remove a layer of waste associated with
        chasing the waves. This will provide additional capacity that was not available
        before. Many companies discover that the initial leveling effort allows them to
        “catch up” with orders, and that they are overproducing based on the initial
        assumptions. It is possible to either reduce the resources or to increase sales if
        possible.
            Let’s look at a specific example. The data in Table 7-1 represents a simplified
        version of a real situation, but the concepts can be applied to more complex situa-
        tions as well. In our example we will level 10 parts, designated A through J, each
        with varying demands. The “Other” items that are produced in the process had
        low volume requirements, an average of 125, and will not be leveled by indi-
        vidual part. The total daily volume for all products,  including the  “Other”
        items, is leveled. In fact the “Other” items and the quantities will vary, and it is
        possible to make adjustments by increasing or decreasing the total running time
        if the actual requirement is more or less than planned. This adjustment does not
        alter the leveling effect for items A through J.
            Based on the volume requirements for the leveled items, a production pat-
        tern is developed to minimize the negative effects of changeover (the process
        has  improved, but the time  is still greater than desired—for now). Items  A




                                              Daily Average
                                    Part
                                                Demand
                                     A             250
                                     B             220
                                     C             210
                                     D             128
                                     E             125
                                     F             75

                                     G             60
                                     H             45
                                     I             45
                                     J             35
                                   Other           125

                                   Total          1,318

        Table 7-1. Volume Requirements by Part
   173   174   175   176   177   178   179   180   181   182   183