Process Validation - Injection Moulding Process

Dear Brothers & Sisters,

Greeting of the Day..

I need your assistance regarding Process Validation - Injection Moulding Process (Special Process - where the resulting output cannot be verified by subsequent monitoring or measurement)

We are the manufacturers of Kitchen Cutlery Items (Spoon, fork, knife, etc.,), Plastic Cups & plates. As per the ISO 9001:2015 - 8.5.1.f (process validation / revalidation) we need to have this practice but it is not our customer or regulatory requirement for us.

My question is how to perform this validation process hence we have already set the parameters (Machine, Process),

• For Maintenance, Ensure the machine parameters that matching with the Machine Supplier requirements (IQ purpose)
  
• I suggested my production team to do the following:

(i) Identify the CPP (Critical Process Parameter) & CQA (Critical Quality Attributes) involved in it.
(ii) Perform Failure Mode Effective Analysis (FMEA - Process & Product) particularly for CPP & CQA.
(iii) Perform Trial production and record the data ( for OQ purpose)
(iii) Collect the data for short term study (Sample lot / batches)
(iv) Perform Initial Capability Study to ensure the Cpk < 1.33 and approve the process
(v) Collect the data for long term study (Samples from Continuous regular production on a daily basis up to subgroup level)
(vi) Perform Ongoing SPC Study to ensure the Ppk < 1.67 and Validate the process.

• Prepare a revalidation criteria to do revalidation when and where required and follow the above activity to revalidate the process.

Can you help me out either I am on the right direction or need improvement on my way?

 

Clause 8.5.1f requirement is intended for those processes with outputs where conformity with the product requirements cannot be readily/economically determined by subsequent measurement or inspection. So, focus first on the product requirements.

1. Are there product requirements that can be readily/economically verified like weight, length, diameter, etc? Subsequent measurements or inspections to verify this type of product requirements can be readily/economically performed. Your organization can be assured of conformity prior to any delivery. If you perform measurements or inspections for this kind of product requirements, then 8.5.1f is not applicable to this.
2. Are there product requirements that are less than readily/economically verified (maybe because determining the conformity is destructive to the product)? Such product requirements can include flexibility, sturdiness, strength, etc. Tests instead of inspections is more appropriate to determine conformity for these product requirements. Since 100% of all products cannot undergo such tests, special controls should be applied for this. This is where 8.5.1f requirements are applicable.

Next, ask yourself: Do we need special controls to ensure our ability to achieve conformity as per Item #2 above?

8.5.1f is about the validation/re-validation of the ability to achieved conformity with product requirements (i.e. planned results). Ensuring your ability will necessitate setting of criteria for your processes. Criteria can be based on the 4Ms (i.e. man, material, method, machine). Criteria for your type of organization can include process capability, stability, material acceptability, machine performance, job set-up verification, operator qualifications, etc.

If you need to perform all the special controls you have posted to validate the ability of your production processes to achieved conformity with product requirements, then, I believe, you're on the right direction.

 

Thank you brother for the detailed clarification

and also I have a doubt on, what if incase of only "mould validation". what should I do?

For e.g: Case1:

New Mould design came to me for approval, I do the comparative study with previous samples (dimensions and material) and approve for mould developing
Once it developed, it will come for machine trial (here we need to perform OQ and PQ, right?)

(* with existing machine setup - IQ required or not?)

if so, how to perform this OQ and PQ?

Kindly help me out this as well, brother

 

Good day Lafir;
Two things to consider....
1- The term "validation" is most applicable to design activity (i.e. will the product fulfill the application intended by the customer, NOT does the product meet the drawing specifications. (confirming the product meets the product/drawing
specifications is "verification". This is not semantics, as the difference between "validation" and "verification" is significant. Specifically, ISO 9000:2015 defines the two as follows...
3.8.12 Verification= Confirmation, through the provision of objective evidence that specified requirements have been fulfilled.
3.8.13 Validation = Confirmation, through the provision of objective evidence that the requirements for a specific intended use or application have been fulfilled.

2- Considering the process (Injection molding) and the product you are describing, I believe you may be overthinking/overcomplicating this. Is it possible you are confusion "verification" with "validation" ?
An example of meeting the requirements of 8.5.1-f in a manufacturing setting would be heat treat of bulk metal items, wherein, it is impossible to verify the hardness (performance) of each part. In that case, methods of product sampling and process control (including SPC) are often employed to meet this requirement.

Hope this helps.
Be well

 

Perfect. You are on the right direction. You actually employed both - initial validation study and subsequent verification of the validated model.

 

Wouldn't measurement be also considered?

 

Yes. Measurement is part of the "method" in 4Ms. Can't do capability and stability study without measurement. However, the measurement employed here is intended to validate the ability to achieve planned results of the process - not necessarily to validate the output of the process.

 

Is it safe to say that it might be neccesary to calibrate and/or verify the measurement equipment used for certain parameter considered critical for the process (e.g. temperature, speed, etc.)?

 

Not just "safe to say that it might be necessary", it is, actually, necessary to calibrate or verify measuring equipment employed for "special processes".

Since the statement under 8.5.1f of the 2015 version didn't give much details on how "validation" is to be carried out, I make use of the 7.5.2 of the 2008 version for additional guidance. See below statement:

7.5.2 Validation of processes for production and service provision

The organization shall validate any processes for production and service provision where the resulting output
cannot be verified by subsequent monitoring or measurement and, as a consequence, deficiencies become
apparent only after the product is in use or the service has been delivered.
Validation shall demonstrate the ability of these processes to achieve planned results.
The organization shall establish arrangements for these processes including, as applicable,
a) defined criteria for review and approval of the processes,
b) approval of equipment and qualification of personnel,
c) use of specific methods and procedures,
d) requirements for records (see 4.2.4), and
e) revalidation.​