Which chart would be apporiate

[Skyrocketing]

Hello all,

Years and years in my company we are using control chart for attributes non simular to nothing u can find around, and it is conform to our customers and IATF auditors.
In that chart is written product and process characteristics and based on control plan frequency it is file, nothing more than 1 hour interval, so for example every two hours there is gauging go no go for šećera threads and worker needs to put 0 for all ok, 1-to how much nok parts been found in hourly control eto...
For visual inspections which are 100%, example visual control for porosity, cracks, damages etc we put number of defective parts per hour...
So mY question is, is this ok or there is some kind of chart to improve this recording?
Thank you

 

[Bev D]

This is an excellent question and one that vexes many quality practitioners.

There are two thing we need to know to select the best control chart scheme: the actual circumstances of the process being charted,including the measurement method and the actual results plotted in time sequence.

You have given us a decent explanation of the first but without the data and some indication of sample size there is really no way to determine the best chart scheme. Without knowing anything about the actual data the default control chart that usually works is the I,MR chart…

 

[Steve Prevette]

Yes, a copy of the chart would help answer your question. If you don't want to share company data, remove the labels and just put in generically what is being measured.