Optimizing Quality and Measurement Systems for a Precision Machined Assembly
Automobility Enterprises (AE) was engaged by a Tier 1 automotive customer struggling with high reject rates on a critical, precision-machined assembly. This complex product required stringent quality validation through intricate measurement processes, which were failing to reliably identify and prevent defects. The core request was to validate the supplier’s production process and optimize the overall quality output.
The Challenge: Unstable Quality and Unreliable Data
The supplier was experiencing a frustrating and costly high reject rate, but their internal quality control systems were failing to pinpoint the true source of the dimensional variation. Initial analyses suggested a specific operation was the primary culprit, but the fundamental issue lay deeper in the data itself.
AE's Intervention: Root Cause and Measurement System Analysis (MSA)
AE executed a thorough root cause analysis, extending beyond the process floor and into the quality lab.
- Deep Root Cause Analysis (RCA): Initial process review confirmed that the majority of rejects appeared to stem from a single, critical process point.
- Measurement System Analysis (MSA): However, upon further evaluation, AE conducted an in-depth Measurement System Analysis (MSA). This critical review revealed the true systemic problem: the existing measurement system was fundamentally flawed and not correctly designed or validated to meet the extremely tight tolerances of the product design. The system’s inherent variation (gage error) was consuming a significant portion of the allowable product tolerance, making it impossible to confidently separate product variation from measurement error.
The Solution: SPC and High-Fidelity Measurement Strategy
AE moved swiftly to establish a robust and reliable quality validation system:
- Developed a New Measurement Strategy: AE designed a brand-new measurement system strategy tailored specifically to the tight tolerances of the precision assembly.
- Gauge R&R Validation: The new system was rigorously validated using a Gauge Repeatability and Reproducibility (Gauge R&R) study. This confirmed the system’s variation was now appropriately minimized, making the data trustworthy and ensuring the system was capable of accurately assessing product quality.
Incorporated Statistical Process Control (SPC): The validated measurement system was integrated with Statistical Process Control (SPC) tracking. This step was crucial, as it established a dynamic monitoring system that provided adequate warning by detecting process shifts before they resulted in out-of-specification defects.
The Outcome: Reduced Variation and Enhanced Safety Margins
The implementation of the new, reliable measurement and control system yielded immediate and lasting benefits:
- True Process Understanding: The accurate data provided by the new system revealed that the variation coming from previous upstream operations could also be significantly reduced.
- Increased Safety Margin: By controlling upstream variation and employing a validated, high-fidelity measurement system, the overall process capability improved, creating an even higher safety margin against the specified design tolerances.
- Sustainable Quality: AE successfully transitioned the client from a reactive inspection state (detecting defects) to a proactive control state (preventing defects), resulting in a sustained reduction in the high reject rate and significant cost savings for the customer.
Strengthen your quality and measurement systems
Our fractional executives embed with your operations to solve critical challenges.
Start with a diagnostic assessment to understand where we can help.