Defects and Metrics
What does DPU stand for?
Defects Per Unit
What is cycle time?
Cycle time is the total time taken to complete one process cycle, from start to finish.
What does COPQ represent?
Costs of Poor Quality represent the costs of failing to produce a quality product or service.
What is the goal of achieving Six Sigma quality?
The goal is to reduce process variation and improve quality to fewer than 3.4 defects per million opportunities.
How do you calculate the First Time Yield (FTY)?
FTY = (Number of good units produced on first pass) / (Total units produced)
What is the formula for calculating DPMO?
DPMO = (Total number of defects / Total opportunities) x 1,000,000
How is Takt Time related to cycle time?
Takt Time is the maximum allowable time to produce a product to meet customer demand, influencing the cycle time needed to achieve it.
Name two components of COPQ.
Internal failure costs and external failure costs.
Compare Three Sigma and Six Sigma.
Three Sigma allows 66,810 defects per million opportunities, while Six Sigma allows only 3.4.
What does a high RTY indicate about a process?
A high RTY indicates that a high percentage of products pass through multiple processes without defects.
Define "defect" in the context of Six Sigma.
A defect is a product or service failing to meet specified requirements.
Describe the significance of cycle time in process improvement.
Reducing cycle time can increase efficiency, lower costs, and improve customer satisfaction.
How can organizations measure COPQ?
- By tracking costs related to defects, rework, returns, and warranty claims.
Define the term "First Time Yield" (FTY).
FTY measures the percentage of products that meet quality standards without rework.
Explain the importance of sample size in yield calculations.
A larger sample size provides more reliable data and a better estimate of process performance.
How do upper and lower specification limits affect quality?
They define the acceptable range for a product or service; anything outside of these limits is considered a defect.
What factors can affect cycle time?
Factors include process complexity, resource availability, and technology used.
Explain the impact of COPQ on profitability.
High COPQ reduces profitability by increasing operational costs and decreasing customer satisfaction.
What is Rolled Throughput Yield (RTY)?
RTY is the probability of a product passing through multiple processes without defects.
What role does confidence level play in yield calculations?
The confidence level determines the degree of certainty in the yield estimate and influences decision-making.
Explain the importance of measuring defects in the DMAIC cycle.
Measuring defects helps identify improvement areas and tracks process changes' effectiveness.
How can reducing cycle time benefit an organization?
It can lead to faster delivery times, improved productivity, and greater competitiveness.
Discuss strategies to minimize COPQ in a business.
Implement quality control measures, train employees, and improve processes.
Explain how Six Sigma levels influence defect rates.
Higher Six Sigma levels correlate with lower defect rates, improving quality and customer satisfaction.
Discuss how yield calculations can drive process improvement.
By analyzing yield rates, organizations can identify problem areas and implement targeted improvements to enhance quality.