Validation of Special Processes - Are Casting and Forging Special Processes

S

slack157

Hi,

there are a few talks on special process out there in the forum, but i do have to ask again.

How to validate the special process, are casting and forging special process?
Thanks in advance for any comments.
 

somashekar

Leader
Admin
Hi,

there are a few talks on special process out there in the forum, but i do have to ask again.

How to validate the special process, are casting and forging special process?
Thanks in advance for any comments.
Buy the way these processes are, they are termed special because you control somethings at some places to get your desired thing.
Now what are the things you control and within how much varience must be determined in advance by way of some trials and experiments, such that your desired output is achieved. Coupled with this is the qualification of the machine and controls and calibrations of process measuring instruments, the qualification of the person who operates the machine.
The above constitutes validation, and you must know what changes when faced with calls for a re-validation.
 

John Broomfield

Leader
Super Moderator
Hi,

there are a few talks on special process out there in the forum, but i do have to ask again.

How to validate the special process, are casting and forging special process?
Thanks in advance for any comments.

slack157,

Yes, casting is a special process (as is forging) because this process results in products that cannot be economically verified.

A way to do it:

Design each of the casting processes per the requirements of clause 7.3.

In so doing determine the key variables, verify and validate (possibly by slicing and microscopic examination of the cast product).

Specify criteria for control of these key variables in the documented procedure/plan for casting.

Keep a record of the monitoring and measurement of these key variables for each casting or batch of castings.

Re-validate if changing input materials, mold materials, temperatures, cooling profile or operators (per 7.3.7 and 7.5.2).

John
 

Paul Simpson

Trusted Information Resource
slack157,

Yes, casting is a special process (as is forging) because this process results in products that cannot be economically verified.
Not convinced. :nope: Depending on the application of the casting / forging it may be you can easily inspect / test to see that the process has been carried out effectively. Otherwise every process becomes special.

But nevertheless I'll go with it for now to deal with the next part of the answer.

A way to do it:

Design each of the casting processes per the requirements of clause 7.3.
C'mon John! Is the use of clause 7.3 for process design your answer for every question? :D

In so doing determine the key variables, verify and validate (possibly by slicing and microscopic examination of the cast product).

Specify criteria for control of these key variables in the documented procedure/plan for casting.

Keep a record of the monitoring and measurement of these key variables for each casting or batch of castings.

Re-validate if changing input materials, mold materials, temperatures, cooling profile or operators (per 7.3.7 and 7.5.2).

John
All of these elements can be covered in clause 7.5.1 and 7.5.2 so why is there a need to add the requirements to plan the design of your processes including the verification, validation, etc. :frust:
 

somashekar

Leader
Admin
Not convinced. :nope: Depending on the application of the casting / forging it may be you can easily inspect / test to see that the process has been carried out effectively. Otherwise every process becomes special.

I prefer to shift the focus about validation from the inspecting testing angle to the parameter and control angle.


C'mon John! Is the use of clause 7.3 for process design your answer for every question? :D
All of these elements can be covered in clause 7.5.1 and 7.5.2 so why is there a need to add the requirements to plan the design of your processes including the verification, validation, etc. :frust:

That is right there what you say. Validation is validation and different from design and development activity.
Why mix this design and development thought with other well defined activities. On a larger scale everything comes into the PDCA. So is validation like Validation plan, Validation, Any significant changes, Re-validation. I would not take a design and development clause reference to state this.
 
S

samsung

Not convinced. :nope: Depending on the application of the casting / forging it may be you can easily inspect / test to see that the process has been carried out effectively. Otherwise every process becomes special.

All of these elements can be covered in clause 7.5.1 and 7.5.2 so why is there a need to add the requirements to plan the design of your processes including the verification, validation, etc. :frust:

If casting and forging don't fall under the 'special process' category, then IMHO, one doesn't have to do anything except excluding 7.5.2 from the scope of QMS.
 
S

slack157

Thank you all, you guys are brilliant.

Just to give more details in order to proceed the talks,i think they are,casting parts may have composition,microstructure and mechanical requirements which will never be economically control.And so do forging parts.

Well, in that case, questions come up,
since speical process probably be always critical process,is there needs to write a procedure to define and validate the speical process?Because there is supposed to be only 6 main procedures.

is there some examples for reference?
 

somashekar

Leader
Admin
Because there is supposed to be only 6 main procedures.

Oooohh. From where did you get this only 6 main procedures... ?
ISO 9001 calls for documented procedures to be established at some clauses. It is not limiting you with any number. Do not limit yourself.
When you read the 7.5.2 it says.,
The organization shall establish arrangements for these processes including, as applicable ... a) b) c) d) e)
These arrangements can be a Plan, Validation protocol or procedure (documented procedure if necessary)
Records of validation is covered in d)
 
S

slack157

Oooohh. From where did you get this only 6 main procedures... ?
ISO 9001 calls for documented procedures to be established at some clauses. It is not limiting you with any number. Do not limit yourself.
you are right,there is indeed no numbers of documented procedures as required by iso, but i do have been trained to document the procedure of NC,CA,PA,IA,DC&CI
 

Paul Simpson

Trusted Information Resource
If casting and forging don't fall under the 'special process' category, then IMHO, one doesn't have to do anything except excluding 7.5.2 from the scope of QMS.
Yet again you selectively quote my work and even choose to highlight parts of my statements (without even mentioning that the highlight is yours) when the statement is meaningless without either explanation or the original quote that I referred to. :mad:

So when I quoted John Broomfield :

slack157,

Yes, casting is a special process (as is forging) because this process results in products that cannot be economically verified.
Not convinced. :nope: Depending on the application of the casting / forging it may be you can easily inspect / test to see that the process has been carried out effectively. Otherwise every process becomes special.

But nevertheless I'll go with it for now to deal with the next part of the answer.
The key line that you omitted was the last one from my reply:
But nevertheless I'll go with it for now to deal with the next part of the answer.
By missing this out it made the whole of the rest of the post meaningless. :frust:


A way to do it:

Design each of the casting processes per the requirements of clause 7.3.
C'mon John! Is the use of clause 7.3 for process design your answer for every question? :D.
So here I am saying that even if you accept the processes are special there is no need to apply clause 7.3.
In so doing determine the key variables, verify and validate (possibly by slicing and microscopic examination of the cast product).

Specify criteria for control of these key variables in the documented procedure/plan for casting.

Keep a record of the monitoring and measurement of these key variables for each casting or batch of castings.

Re-validate if changing input materials, mold materials, temperatures, cooling profile or operators (per 7.3.7 and 7.5.2).

John
All of these elements can be covered in clause 7.5.1 and 7.5.2 so why is there a need to add the requirements to plan the design of your processes including the verification, validation, etc. :frust:

So, in summary, the purpose of my multipart response to John's post was to:
  • challenge whether casting and forging are necessarily special processes. For applications where casting / forging strength and leak resistance isn't critical they may not be
  • say that even if they are special processes then that doesn't mean we have to apply the requirements of design control (7.3) to the processes as elements 7.5.1 and 7.5.2 would adequately define controls required

Please do me the courtesy of quoting my posts correctly (as I do for you). If not please do not quote me at all.
 
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