Process Performance denotes whether a process is performing correctly in a certain period of time within the overall requirement. It calculates the measurable property of a process.
Process Performance Index is nothing but an estimation of the capability of the process during its initial set-up. It demonstrates how a process is able to create the output to its overall specifications.
USL = Upper Specification Limit, LSL = Lower Specification Limit.
Food kept at a restaurant should be between 38°C and 49°C . The process used to keep the food at the same temperature has a process standard deviation of 2°C. What is the process performance of the process?
USL (Upper Specification Limit) =49°C LSL (Lower Specification Limit) =38°C Standard Deviation =2°C Mean = (49 + 38)/2 = 43.5
Process Performance & Process Performance Index
|Process Performance :|
|Process Performance||= (49 - 38) / (6 * 2)|
|= 9 / 12|
|Process Performance Index :|
|(USL-mean/ 3*std.Dev)||= (49 - 43.5) / (3 * 2)|
|(mean-LSL/3*std.Dev)||= (43.5 - 38) / (3 * 2)|
|Now, find the minimum value.|
|Process Performance Index||= min (Solution 1, Solution 2)|
|= min (0.917 , 0.917)|