The purpose of the validation is to identify a capable mould-process combination, which will achieve required part dimensions and tolerances consistently and repeatedly.
A mould-processing window is set during qualification to assure the quality of parts before they are actually manufactured and supplied to the customer.
We provide a complete qualification report with the mold manual outlining process and installation parameters.
Main steps of process validation are,
- Process stability test
- Purpose: Identify gross mechanical design/construction defects, which can cause part variation over time.
- Output: Ensure that Mould is free of any mechanical defect to avoid short shot, flash, blemishes, scratches, water leakage, voids, etc.
- Mould viscosity test
- Purpose: Identify the maximum and minimum fill rates allowed for the mould with a specific plastic material.
- Output: Best Mould fill rate (& viscosity) & Peak injection pressure for particular mould, machine, material.
- Balance of fill Analysis
- Purpose: Evaluate thermal and flow balance of the plastics melt distribution system in the mould.
- Output: Mould feed system is well balanced and process parameter effect on each cavity will not vary more than 5%. This ensures better process window.
- Gate seal teat
- Purpose: Identify hold conditions to freeze the gate and thus correct part weight, and hold parameters.
- Output: Right Hold time and pressure with correct part weight.
- Multi cavity analysis
- Purpose: To Ensure all cavities in the mould deliver the same quality. No difference between cavities for CTQ (critical to quality) dimensions.
- Output: All cavities of mould is capable to deliver CTQ dimension within specific range
- Process capability study (SPC)
- Purpose: To ensure the process can meet the specified CTQ tolerance ranges.
- Output: The process is capable to deliver parts within specified tolerance consistently.
- Process centring
- Purpose: To ensure that the capable process spread is near centre (target) and meet the specified CTQ tolerance ranges.
- Output: The process is capable to deliver parts within specified tolerance consistently over period of time.
