Preliminary listing of special product and process characteristics - APQP

Hi everyone!

I need your advice in order to create a form to document the special product and process characteristics.

What parametres of the characteristics shoul I register?

Do you have an example form?

Thank you!

You don't need a special form. Potential SCs are typically identified on the DFMEA and confirmed on the PFMEA using the Class column. Special product characteristics should then be documented on the product drawings and on the control plan. Special process characteristics are documented on the control plan,

I would add that these characteristics can also be noted on the drawing. When I worked at GE Aircraft Engines even special process characteristics were noted. The drawing is usually the ‘mother’ document…

Yep to Bev's great comment above, typically approved drawings are akin to the mother lode of info and order of precedence

Special Characteristics are identified on the drawing (if the customer is providing it), otherwise you need to identify them while doing DFMEA.
Mainly these characteristics are of two types :

1. Critical (Safety) characteristics (CC) - Its mainly given for regulatory requirements (regulation/Legal or EHS) purpose. (Severity - 9 to 10)
2. Significant characteristics (SC) - It is usually observed at the lower assembly levels, for functioning of product or assembly/fitment point of view. (Severity - 5 to 8)

If the drawing doesn't have these characters you can identify on your own as per your process
(For Example, first process is CNC machining, in which ID Ø62 mm is formed and the next operation is VMC machining, and the ID of Ø62 is being used by the fixture to hold the part vertically, so Ø62 is significant for us, as it won't fit if its not properly maintained during CNC machining)

For documentation, you can make an excel file to note down the SC's and CC's from the drawing of the Product (Attachment 1);
and, for Process Special Characteristics you need to go through each Process Parameter to check whether its affecting the fitment or functioning or life of the product (Attachment 2).

Note : These attachments were prepared for HPDC process. Also if anyone finds anything wrong with this format, please teach me so that i can correct it. Thank you.

Thank you for your great contribution arun007.chauhan !