SPC scripting - Why writing information back into a database is important

[#1]

Problem description - Process is unstable:

• Influence of time or unknown variable
• Process moves slowly towards out of spec
• An incident shift the process

Overview SPC:

• SPC is like telling a dog to “stay”. Wherever the process is, it should remain in that place.
• A stable phase should be defined and notify the operator when the process is out of control limits before it’s out of spec.

Problems with SPC:

• Process screening platform gives a lot of false positives and is therefore not always useable for prioritizing improvements
• Default SPC control limits on our data are often too strict:

• When new data are analyzed, the control limits shifts automatically.
• A change in the process can be overlooked.

The solution should:

• Generate, store and update individual control limits.
• Help in setting limits for multiple variables.

SPC scripts

• The Script generates a table with each variable that contains spec limits.
• It tries to load existing control limits into the table from the DB
• It adds scripts to store and set the limits.

Slides and Demo are available on the attachment.

[#2]

Great demo Mauro, thanks for sharing the script !