When testing the POP2 the Critical Parameter Sheet (CPS) is a useful tool. With this you look at the output of a process step e.g. thickness distribution, strengths, radial and tangential deviation, lifespan (test by means of Arrhenius), etc. You look at the incoming products, which are unchangeable and the parameters/consumables that come into play in this process step. Many of these materials and settings have influence on various output criteria. A lot of time can be won when this is taken into account.

The CPS is used as an input for the Design of Experiments (DoE). The DoE checks which parameters have influence on the quality. Stability after the changes is also checked.

• Relatively simple problems can be solved by using ACTI
• For the more severe problems it is sensible to use Six Sigma or an Ishikawa diagram
• Form problems which you have no clue how to solved hem use TRIZ

Make at the end of this phase a run to see the stability of production and to see where you are in relation to the process window (Cpk). Look also at the rejected products, make a Parero to see the what are worst offenders. Try to find what the causes are and try to solve them. Some problems can also be solved in the next phase (pollution for example).