Everything about Process Capability Index totally explained
In
process improvement efforts, the
process capability index or
process capability ratio is a statistical measure of
process capability: The ability of a process to produce output within
specification limits (USL and LSL, not to be confused with control limits, UCL and LCL). The concept of process capability only holds meaning for processes that are in a state of
statistical control.
If the upper and lower specifications of the process are USL and LSL, the target process mean is T, the estimated mean of the process is
far from T) or with high variation.
Fixing values for minimum "acceptable" process capability targets is a matter of personal opinion, and what consensus exists varies by industry, facility, and the process under consideration. However, at least one academic expert recommends the following:
| Situation |
Recommended minimum process capability for two-sided specifications |
Recommended minimum process capability for one-sided specification |
| Existing process |
1.33 |
1.25 |
| New process |
1.50 |
1.45 |
| Safety or critical parameter for existing process |
1.50 |
1.45 |
| Safety or critical parameter for new process |
1.67 |
1.60 |
| Six Sigma quality process |
2.00 |
2.00 |
It should be noted though that where a process produces a characteristic with a capability index greater than 2.5, the unnecessary precision may be expensive.
Further Information
Get more info on 'Process Capability Index'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://process_capability_index.totallyexplained.com">Process capability index Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
