Lesson 6- Business Results for Projects

Key Takeaways

1. DPU is the average number of defects per unit of a product 2. TPY is the number of acceptable pieces divided by the number of starting pieces 3. RTY is the probability of entire process producing zero defects 4. FPY is the number of products which pass without the total number of units 5. DPMO or NPMO is a measure of process performance 6. Sigma Level is a measure of the error rate of the process 7. COQ is the cost incurred by a process because it cannot consistently make a perfect prodcut 8. Cp is defined as the inherent variability of a characteristic of a process or a product

Defect Per Unit (DPU)

6.3 Defect Per Unit DPU= Total number of defects / Total number of units DPU Metric is not percentage

Throughput Yield (TPY) and Rolled Throughput Yield (RTY)

6.4 Throughput Yield and Rolled Throughput Yield Throughput Yield (TPY) is the number of acceptable pieces, at the end of a process, divided by the number of starting pieces, excluding scrap and excluding rework. TPY is using to measure single process only. >TPY Formula: TPY = e^(-DPU) , DPU = -ln(TPY) Rolled Throughput Yield (RTY) is the probability of the entire process producing zero defects. >It's important as a metric when a process has excessive rework. >Total Defects Per Unit (TDPU) is defined for a set of processes. >RTY Formula: RTY=e^(-TDPU) , TDPU=-ln(RTY) First Pass Yield (FPY) is the number of products which pass without any rework of the total number of units. >RTY=FPY1+FPY2+FPY3+FPYn >FPY Formula: Total number of quality products / Total number of units =(Total number of units - Number of defective units) / Total number of units

Defect per Million Opportunities (DPMO) and Sigma Level

6.5 Defect per Million Opportunities and Sigma Level Defect per Million Opportunities (DPMO) >Also known as non-conformities per million opportunities (NPMO) >A measure of process performance >Standardizes the number of defects by the number of opportunities. >Opportunities for a defect can very greatly between processes. >DPMO Formula: DPMO= (Total number of defects / Total number of opportunities) * 10^6 >>>Total number of opportunities = Units * number of opportunities per unit Sigma Level: A measure of the error rate of the process. >Generally based on DPMO >There are different ways to get to a sigma level metric: >Six sigma conversion table >DPMO-Sigma Calculator

Cost of Quality and Process Capability

6.6 Cost of Quality and Process Capability Cost of Quality (COQ): The cost incurred by a process because it cannot consistently make a perfect product. Process Performance= Preventive Cost: >Cost incurred in preventing a failure. >Example: Training and improvement programs +Appraisal Cost: >Cost incurred to test a product for quality conformance >Example: Testing, audits, and inspection +Internal failure cost >Cost associated with defects identified before a product reaches the customer. >Example: Rework and scrap +External failure cost: >Cost associated with defects after a product reaches the customer >Example: Warranty claims, returned products, and loss in reputation Process Capability (Cp): 1.Another way to measure performance 2.Inherent variability of a characteristic of a process or a product 3. An indicator of the capability of a process. 4. How well or how poorly is the process meeting customer requirements or needs. >Formula of Cp: Cp = [Upper specification limit (USL) - Lower specification limit (LSL)] / (6*σ)