Presentation on theme: "Six Sigma Overview. 4 Sigma Process Capability 99.38% Current Standard 6 Sigma Process Capability 99.99966% World-Class Long-Term Yield 3 Sigma Process."— Presentation transcript:
Six Sigma Overview
4 Sigma Process Capability 99.38% Current Standard 6 Sigma Process Capability % World-Class Long-Term Yield 3 Sigma Process Capability 93.32% Historical Standard The Classical View of Performance Six-Sigma is a philosophy: Why isnt 99% acceptable good enough...?? –20,000 lost articles of mail every hour. –15 minutes each day of unsafe drinking water. –5,000 incorrect surgical procedures per week. –4 or more accidents per day at major airports. –200,000 wrong drug prescriptions each year. –7 hours each month without electricity.
History of 6 Sigma 6 Sigma manufacturing philosophy came from Motorola They recognised that sufficient process improvement would not occur using a conventional approach to quality. It was developed to help them reduce variation within a process by focusing effort on improving inputs to a process rather than reacting to outputs. The process was failing the customer expectations –Traditionally, processes aimed for process capability of 3 to 4 sigma (Cpk=1.0 to 1.33 or 93% to 99.3% acceptable) –The customer received 6200 defective product per million at best –Processes now aim for 6 sigma (Cpk=2) –The customer would receive 3.4 defective product per million On target, minimum process variation
6 sigma Process Capability What is it (CPK) 3 Sigma ( Process capability of 1 CPK ) –if the process (lorry) slightly varies then the scrap or damage will occur 6 Sigma ( Process capability of 2 CPK ) –if the process (lorry) varies, there will be no scrap or damage Curbs = required process tolerances CPK of 2 (6 sigma) CPK of 1 (3 sigma)
Variation exists in everything. Even the best machine cannot make every unit exactly the same. Improved capability, becomes a necessity, due to the need of : improved designs lower costs better performance All of this leads to the need of tighter tolerances This means that the ability to operate to a tight tolerance, without producing defects becomes a major advantage Understanding Variability
Improvement methodology On target, minimum process variation KPIV Key Process Input Variables The Process X1X2X3 Controllable Inputs N1N2N3 Inputs: Raw materials, components, etc. Uncontrollable Inputs Y1, Y2, etc. Quality Characteristics: Outputs
D M A I C Define Measure Analyze Improve Control Improvement methodology
Define Improvement methodology Define terms of reference (Charter the project) –Team / customer / project charter –Brain storming –Mind maps –Affinity diagrams –High level Process Maps –Systematic diagrams / Fault tree –Business Process Mapping Define customer requirements (Voice of the customer) –QFD Quality Function Deployment To develop a team charter. To define the customers and their requirements (CTQ Critical to Quality). To map the business process to be improved Characteristics Importance out of 10 Product / customers
Define Define terms of reference (charting a project) –What you can deliver to the customer and the support you need from the customer to facilitate a successful improvement (contract of engagement) Brain storming, Mind maps, Affinity diagrams, High level Process Maps, Systematic diagrams / Fault tree, Business Process Mapping –Tools to explore a problem, project or current thinking. –Tools to group those ideas logically. –Then define a route map to improvement, the risk involved and how to mitigate that risk. Define customer requirements (Voice of the customer) –QFD Quality Function Deployment, is a method of defining what the customer needs, what is critical to there business success & prioritise objectives to meet the customer need.
Measure Improvement methodology Voice of the process –Data Collection - 7 quality tools –Tally charts –Bar charts –Pareto –Run charts –Control charts –Cause & effect –Check sheets –Evaluate measurement systems Gauge R&R Select measures of performance –Quality Function Deployment To measure and understand baseline performance for the current process
Measure Voice of the process (7 quality tools) –Tally charts, Bar charts, Pareto, Run charts, Control charts, Cause & effect, Check sheets. Evaluate measurement systems Gauge R&R –Every process has variation and measurement system, tools & cmm are no exception. –Typical your measurement process needs to be ACCURATE, REPEATABLE & REPRODUCIBLE to less than 10% of the tolerance you are trying to measure to & proven to be so. Select measures of performance –QFD Quality Function Deployment is a method of defining what the customer needs and what is critical to there business success and prioritising performance measures to support the customers need.
Analyze Improvement methodology Investigate source of variation (Special cause / Common causes) –Stratification of data to get information –Cause & effect –CP & CPK –Fault tree –Contingence analysis –FMEA (Failure Mode Effect Analysis) –Design of experiments (DOE) –Detailed process maps Seek to:- Prioritise Understand Clues Causes Monitor improvements Look for signals
Lost Shoe Lost Nail Lost Horse Lost Soldier Lost Battle Why Battles are Lost Current Window of Consideration CauseFailure Mode Effect FMEA Identifies the ways in which a product or process can fail Estimates the risk of specific causes with regard to these failures Prioritizes the actions that should be taken to reduce the chance of failure FMEA (failure mode effect analysis)
ífactors which shift the average ífactors which affect variation ífactors which shift the average and affect variation ífactors which have no effect A1A2 D1=D2 B1 B2 C1 C2 DOE - (design of experiments) will help us identify...
DOE - (design of experiments) Measure the Process The Process X1X2X3 Controllable Inputs N1N2N3 Inputs: Raw Materials, components, etc. Uncontrollable Inputs Y1, Y2, etc. Quality Characteristics: Outputs LSL USL Establish the performance baseline
DOE - (design of experiments) Analyse the Process The Process X1X2X3 Controllable Inputs N1N2N3 Inputs: Raw Materials, components, etc. Uncontrollable Inputs Y1, Y2, etc. Quality Characteristics: Outputs LSL USL
DOE - (design of experiments) Improve the Process Uncontrollable Inputs The Process X1X2X3 Controllable Inputs N1N2N3 Inputs: Raw Materials, components, etc. Y1, Y2, etc. Quality Characteristics: Outputs X X X LSL USL LSL USL
DOE - (design of experiments) Control the Process The Process X1X2X3 Controllable Inputs Inputs: Raw Materials, components, etc. N1N2N3 Uncontrollable Inputs Y1, Y2, etc. Quality Characteristics: Outputs LSL USL Check Lists Error Proofing Work Instructions 5 Cs
Analyze Investigate source of variation (Special cause / Common causes) –Special cause variation are the one off, occasional and obvious cause of a process / quality problems. –Common cause variation are the day in day out causes of process problems, because the process is not stable enough, they are hidden (these form 80% of process problems) –Conventional non-conformance management systems seek to solve special cause variation (e.g. concessions) - but these only represent % of the total variation. –6 Sigma addresses all variation.
Improve Improvement methodology Prioritise improvements –Impact Vs Effort –Brainstorming –Affinity diagrams –Solution selection matrix Tactical implementation plans –Deliver improvements (reduce variation systematically) Customer protection Get control Improve process
Improve Prioritise improvements –Tool commonly in uses are, Impact Vs Effort, Brainstorming, Affinity diagrams, Solution selection matrix. –These tools help define the best method to meet the customer need (as defined in the QFD) Tactical implementation plans –Deliver improvements to reduce variation systematically i.e. make a change, note the improvement and make the next improvement. –Critical we need to establish that any change is a change for the good.
Control Improvement methodology Control the process –Recover Control plans Escalation process –Prevent Poke yoke (mistake/ error proof) –Monitor Control charts Checksheets Documentation and Standardisation
Control Control the process –Recover, Control plans, Escalation process. –Prevent by Poke yoke (fool proof the process) to fundamentally remove the rood causes of process variation. –Monitor, Control charts, Checksheets, Documentation and Standardisation, to ensure that stable process is maintained and that the process does not degrade. The objective is to remove the root causes of process variation, management are only left with a few critical input variables in the process that need controlling and not all inputs as before.
Where does 6 Sigma fit with Lean Lean improvements 6 Sigma improvements Lean and 6 Sigma both seek to deliver business improvement They are different in the methods used and tools employed –Lean typically address the total manufacturing environment –6 sigma typical address the root cause of process variation There is significant benefit from using the most appropriate tools and improvement methodology to meet the customer requirements