Difference between revisions of "Process Capability"

Revision as of 18:57, 11 November 2021

Process Capability Index (C_pk)
Process capability index (C_pk) is a statistical tool, to measure the ability of a process to produce output within customer’s specification limits. In simple words, it measures producer’s capability to produce a product within customer’s tolerance range. C_pk is used to estimate how close you are to a given target and how consistent you are to around your average performance. C_pk gives you the best-case scenario for the existing process. It can also estimate future process performance, assuming performance is consistent over time. C_pk is a standard index to state the capability of one process, the higher the C_pk value the better the process is. For instance, Machine 1 has a C_pk of 1.7 and machine 2 has a C_pk of 1.1. From the C_pk value, one can derive that Machine 1 is better than 2. Since C_pk uses specification limits and parts variation (sigma), we can also arrive at the yield processed and losses from the machine.

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-'''Process Capability Index (Cpk)'''<br />
+'''Process Capability Index (C<sub>pk</sub>)'''<br />
-Process capability index (Cpk) is a statistical tool, to measure the ability of a process to produce output within customer’s specification limits. In simple words, it measures producer’s capability to produce a product within customer’s tolerance range. Cpk is used to estimate how close you are to a given target and how consistent you are to around your average performance. Cpk gives you the best-case scenario for the existing process. It can also estimate future process performance, assuming performance is consistent over time.
+Process capability index (C<sub>pk</sub>) is a statistical tool, to measure the ability of a process to produce output within customer’s specification limits. In simple words, it measures producer’s capability to produce a product within customer’s tolerance range. C<sub>pk</sub> is used to estimate how close you are to a given target and how consistent you are to around your average performance. C<sub>pk</sub> gives you the best-case scenario for the existing process. It can also estimate future process performance, assuming performance is consistent over time. C<sub>pk</sub> is a standard index to state the capability of one process, the higher the C<sub>pk</sub> value the better the process is. For instance, Machine 1 has a C<sub>pk</sub> of 1.7 and machine 2 has a C<sub>pk</sub> of 1.1. From the C<sub>pk</sub> value, one can derive that Machine 1 is better than 2. Since C<sub>pk</sub> uses specification limits and parts variation (sigma), we can also arrive at the yield processed and losses from the machine.
-Cpk is a standard index to state the capability of one process, the higher the Cpk value the better the process is. For instance, Machine 1 has a Cpk of 1.7 and machine 2 has a Cpk of 1.1. From the Cpk value, one can derive that Machine 1 is better than 2. Since Cpk uses specification limits and parts variation (sigma), we can also arrive at the yield processed and losses from the machine.