Imagine that you are driving your vehicle over a bridge. The width of your vehicle is

equivalent to the spread or range of the data. The guardrails on each side of the bridge are your specification limits. You must keep your vehicle on the bridge to reach the other side. The Cp value is equivalent to the distance your vehicle stays away from the guardrails and Cpk represents how well you are driving down the middle of the bridge. Obviously if the spread of your data is narrower (your car width is smaller), the more distance there is between the vehicle and the guardrails and the more likely you are to stay on the bridge. For this case study:

A) Why measure Process capability?

B) How is measure Process Capability Measured?

C) Use a graph to evaluate process capability by comparing the spread or range of the product specifications to the spreadof the process data, as measured by SixSigma