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View Full Version : Validation of Processes - Plastic injection moulding - ISO 9001 Clause 7.5.2


lrsiyer
11th March 2007, 11:10 PM
LRS IYER
Hi!

Validation of processes of ISO 9001:2000 tells thru 7.5.2 that if the results are apparent only when the product use is started or subsequent verification of the result of the process could not reveal the process conformity then that process needs to be qualified. My doubt is:
1. A plastic injection moulding process making an automobile part. Drawing is available. After the process/production the operator/ supervisor is able check the product as per drawing. Is this process need to be validated? If yes why?
2. A blow moulding process which is a combination of extrusion and blow moulding. a similar thing that of No.1. Is this process need to be validated? If yes why?
3. an automobile chasis welding process for which the company is having checking method of NDT(LPT). Is this process need to be validated? If yes why?

if these things are answred then I have some more doubts about the same clause applicability.

gszekely
12th March 2007, 02:30 AM
Hello LRS IYER !
I don't know the answer, but there was similar thread if I remember.
Please check this one, and see if you find the answer.
http://elsmar.com/Forums/showthread.php?t=4670
http://elsmar.com/Forums/showthread.php?t=17211
Also scroll down to bottom of the page and see similar threads.
BR
György

vanputten
12th March 2007, 06:18 PM
All 3 questions are "No."

I beleive the process output in all 3 cases can be verified by subesequent monitoring or measuring.

What do you think? Can you verify the process output for injection and blow molding and the welding?

How and when do you know your output is acceptable is the question?

Do you know your product is good before the customer (internal or external) puts it in use?

Regards,

Dirk

Kevin Mader
12th March 2007, 09:54 PM
Maybe (not sure of the full set of requirements in your examples above. I agree with the advice given by the members above.

Reference your design requirements/input documents with respect to the process of manufacture - can they all be verified (e.g. product/quality characteristic confirmed by inspection/test) or do some require validation (can't be fully verified or verification is too costly or destructive; confirmation that the characteristic is consistently achieved under varying process conditions, actual and extreme)? A robust process properly validated (and perhaps with well established process controls) can significantly reduce or eliminate inspection and test.

Good luck.

Kevin

Jennifer Kirley
12th March 2007, 10:25 PM
My understanding of the element is that it is for parts that can't be inspected because, for example, the only acceptable test is a destructive test. In such cases the process must be validated by means of expendable samples or some other validation technique.

I do not think any of your examples qualifies because:

1. The part can be inspected. If there are surfaces which cannot be inspected and are still critical (such as a completely or almost closed hollow part) then a sample may need to be sacrificed for a destructive test.

2. Same as #1.

3. NDT means Non Destructive Test, which is not supposed to render the part unusable. Dyes, ultrasound, magnetic particle, and xrays don't typically destroy the part. If it does, the test is called Destructive Testing. Peel test, bend test, break/shear test...you get the idea I'm sure, so now I'm getting off my soap box.

potdar
13th March 2007, 02:42 AM
LRS IYER
Hi!

Validation of processes of ISO 9001:2000 tells thru 7.5.2 that if the results are apparent only when the product use is started or subsequent verification of the result of the process could not reveal the process conformity then that process needs to be qualified.

The clause is worded a bit differently. It says validation is required when "the product cannot be verified by subsequent monitoring or measurement." It includes what you have listed above.

In your example, validation will not be required if a check on the dimentional parameters / weld integrity is sufficient for your purpose.

However, normally it is found that in such cases, strength and appearance checks will also be necessary. Strength checks, if required, will necessarily need process validation.

Even otherwise, validation of such processes is recommended as these fall under the catagory earlier termed as 'special processes' - processes whose outcome is controlled by controlling the process control parameters.

alekra
17th March 2007, 08:45 PM
Besides the drawings, there may be other specifications with mechanical properties. Normally, then is the case of deciding (depending on the requirements of the specification) on NDT or destructive testing. If a destructive is needed, the validation is necessary.

Ajit Basrur
17th March 2007, 09:55 PM
LRS IYER
Hi!

Validation of processes of ISO 9001:2000 tells thru 7.5.2 that if the results are apparent only when the product use is started or subsequent verification of the result of the process could not reveal the process conformity then that process needs to be qualified. My doubt is:
1. A plastic injection moulding process making an automobile part. Drawing is available. After the process/production the operator/ supervisor is able check the product as per drawing. Is this process need to be validated? If yes why?
2. A blow moulding process which is a combination of extrusion and blow moulding. a similar thing that of No.1. Is this process need to be validated? If yes why?
3. an automobile chasis welding process for which the company is having checking method of NDT(LPT). Is this process need to be validated? If yes why?

if these things are answred then I have some more doubts about the same clause applicability.

You can refer this Process validation Guidance document from GHTF. Though this document is applicable for Medical devices, you can use this document for reference and for better understanding of validation concepts. Also tell which processes have to be validated and which processes to be verified. :bigwave:

Th

lrsiyer
18th March 2007, 02:08 AM
QUalityalways!!!!

Thanks for the needed help:applause: . wrong notion of exempting the 7.5.2 would fetch trouble of facing many questions like strength, UV effect, Physical properties, different metals in fusion etc.

KNOW THE THEORY & DO IT YOURSELF!!!! thanks.
LRS Iyer