What is the difference between statistical process control and stability study

[former_member1124592]

Dear All,

Wanna know the difference between statistical process control and stability study. Clients wants some notification/information  to be triggered in which the users are notified after a specific mentioned time period that corresponding materials are subjected to inspection plan for SPC.

Can i achieve that through stability study?

[former_member42743]

It depends on the purpose of your clients requirement which is not clear in your posting. 

Stability studies are typically ongoing studies of materials under different conditions.  These are mostly used to test, determine, and provide justification for using a specific shelf life value or extending the standard shelf life for a material.  These are mostly use for the pharma and food industries.  They use them to justify and support the general  or normal shelf life applied to a material.

SPC is usually used to control production.  It can be used to analyze product uniformity as well.  It is not  a specific SAP area per say.   A characteristic is set up as a SPC characterisitics which basically tells the system to create bunch of data around this characterisitc and to track it differently than other characteristics.  An SPC characteristic is typically used to analyze a key production value and to make adjustments in real time to the procsss during manufacturing to keep the value within a certain range.  i.e. temperature in a reactor.  Ph values of a slurry.  The viscosity of a fluid used in a process. etc...  These typically have action limits which, (in simplest terms), when reached, should result in an operator making an adjustment to the process to keep it under control.

Depending on your clients business, and how your posting is interpreted, they could be meaning several things.  It's not really clear.

- A production process that they want to mointor across time using SPC.

- A reinspection of inventory on a time basis while it sits in the warehouse to determine if it can still be used or sold, (typically not SPC).  In SAP this would be consider "recurring inspection" or deadlie monitoring.

- Testing of packagaing to determine shelf lives.. (this would be a stability study)

FF

FF

[former_member1124592]

As per my knowledge

Statistical process control is used to measure the accuracy of the machine equipments for critical parameters

The requirement is some thing like this,

Critical Parameters are parameters like Internal Diameter of an hollow cylinder used for making pistoins. These parameters have to be perfect otherwise when other equipments are fixed it will result in faulty material. So after every fixed interval of time the critical parameters are checked and analyzed. This check is observed through graphs where user observes the deviation level from the tolerance level fixed.

Scenrio 1:- I  want some notification to be triggered(can be notification / or a schedule plan through PM module)  in which the users are notified after a specific mentioned time period that corresponding materials are subjected to inspection plan for SPC.

How do i map this scenario?

[former_member207800]

I think you are talking about calibration.

If correct, SAP standard provides functionality "Test equipment management" & "Calibration".

By your master data (maintenance schedule), SAP can create a calibration order automatically.

Please search 'calibration' in this forum.

Regards, DoWook KIM

[former_member1124592]

Hi DoWook KIM,

Thank you for your valuable suggestion. I have got some threads and sap help thread as you have suggested. I am reviewing them.

We Can think about calibration scenario here also as user wants a notification /information /plan anyone ... to know that which materials with their critical parameters are to be sent for validation as per a date. This should be proposed by sap system automatically.

How will user know about it?

This is through those notification /information /plan i was talking before.

Can we map this requirement with your suggestions?

[former_member42743]

Yes.. as it has been pointed out now since you have now explained your busines requirement better to us, this sounds like a calibration issue which is standard functionality.

Create an equipment master for the machine to be calibrated.  Activate inspection type 14.

You should consult with an SAP  Plant Maintenance resource to help you set up an inspection schedule to carry out the calibration.  The inspection lots will than be created automatically.  Based on inspection, the machine can be placed in/out of service.

FF