Question - Control limits
Submitted by philzs on Fri, 01/30/2015 - 13:19
What is the purpose of control limits?174
1 Identifying “rule of seven” patterns in control charts.
2 Increasing process quality from 3σ to 6σ.
3 Specifying the range of acceptable results.
4 Identifying whether the process is in control or not.
Guys,
The answer is 4,
I am not too sure of this one.. Because When your have "rule of seven" the process is out of control and the control limits doesnt help at all to figure if you have rule of seven.
Instead I feel that the "3" is good
what do you think
Forums:
coolpmp69
Fri, 01/30/2015 - 15:36
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Control limit is set based on
Control limit is set based on project requirements and so if any data points of the process is outside the control limits then we need to look closer to determine which process is out of control and the cause of it. Remember the data points should not be closer to specification limts (given by customer) as the project team may npt be meeting the customer requirements. Hopr this helps.
YogSam
Sun, 02/01/2015 - 23:59
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To control
As the name itself says, to see whether you process is in control or not !!.
Identifying rule of 7 is only 1 application of control limits and it is not the 'Only' application so though answer 1 is correct but partially correct.
Choice 2 is wrong. Its always 3 sigma,
Choice 3 is wrong. Thats specification limits not control limits.
Choice is 4 is best choice.