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4.7 Change Control and Deviations

The "Golden Process" validated during qualification is the only approved way to manufacture the part. Any variation from this baseline—whether intentional (Change Request) or accidental (Deviation)—introduces unknown variables. This chapter defines the "No Surprises" policy: suppliers are strictly prohibited from changing the "4M" (Man, Machine, Material, Method) without prior written approval from Dannie Supplier Quality.

Supplier Change Control (PCN)

A Process Change Notification (PCN) is the formal mechanism for a supplier to request a permanent modification to their process.

  • Trigger Events (What Requires Approval?):
    1. Material: Changing resin grade, solder paste type, or sub-tier source.
    2. Machine: Moving molds to a new press, replacing a reflow oven, or adding a new SMT line.
    3. Method: Changing cure time/temp, altering the inspection plan, or modifying test software.
    4. Location: Moving production to a different building or facility.
  • The Notification Window: Suppliers must issue a PCN at least 90 days prior to the proposed implementation date.
  • Validation Requirements:
    • Risk Assessment: FMEA update showing the new risk profile.
    • Capability Data: New Cpk study verifying process stability.
    • Validation: 3-Lot Safe Launch (100% Inspection) results.
  • Approval: Requires SQE and Engineering sign-off. Silence is NOT approval.

Deviation and Concession Control

A Deviation is a temporary permission to ship product that does not meet the specification. It is a "Get Out of Jail Free" card that expires.

  • Types of Deviation:
    1. Pre-Production: Request to use a temporary process (e.g., Soft Tooling) during NPI.
    2. Production: Request to ship a lot with a known minor defect (e.g., cosmetic scratch) to avoid line-down.
  • Risk Evaluation Logic:
    • Critical/Safety: Never Approved.
    • Functional: Approved only with 100% Screening and Engineering concurrence.
    • Cosmetic: Approved with "Limit Sample" and commercial concession (discount).
  • Mandatory Constraints:
    • Quantity/Time Bound: The deviation must specify an exact Quantity (e.g., 500 units) or Expiration Date (e.g., 2 weeks).
    • Traceability: Every box shipped under deviation must be clearly labeled: "DEVIATION #XXXX".
    • Expiry: Once the limit is reached, the permission is automatically revoked. Unauthorized shipments beyond this point will be rejected at the dock.

Unauthorized Changes (The "Silent Killer")

Changing a process without notifying Dannie is a breach of contract and trust.

  • Definition: Examples include "Regrinding" plastic without approval, changing a capacitor brand to a "cheaper equivalent," or skipping a cure cycle to speed up the line.
  • Consequence:
    • Immediate Business Hold: Supplier is placed on "Do Not Source" status.
    • Liability: Supplier is liable for all validation costs, field recalls, and scrap associated with the unauthorized change.
    • Audit: Mandatory on-site "For Cause" audit to re-qualify the process.

Final Checklist

Control Element

Standard

Risk of Failure

PCN Window

90 Days Prior

Unvalidated process shifts

Sub-Tier Change

Requires Approval

Unknown material risks

Deviation Scope

Qty/Time Limited

Permanent "temporary" fixes

Labeling

Visible on Box

Polluting stock with bad parts

Silent Change

Contract Breach

Catastrophic field failure