Table des matières INTRODUCING LEAN SIX SIGMA .............................................................................................................. 2 UNDERSTANDING SIX SIGMA .................................................................................................................. 3 DEFINE ................................................................................................................................................. 3 MEASURE ............................................................................................................................................. 3 ANALYZE .............................................................................................................................................. 4 IMPROVE ............................................................................................................................................. 5 CONTROL ............................................................................................................................................. 5 DESING FOR SIX SIGMA DFSS / DFL(ean)SS ......................................................................................... 6 UNDERSTANDING LEAN..................................................................................................................... 6-%-LEAN METRICS ..................................................................................................................................... 6 FIVE Ss.................................................................................................................................................. 7 JUST-IN-TIME ....................................................................................................................................... 8 TOTAL PRODUCTIVE MAINTENANCE ............................................................................................ 9 INTRODUCING LEAN SIX SIGMA Six sigma principles: To provide reliable, consistent, dependable products to your customers. Six Sigma reduces defects by controlling variability to deliver dependable products to the customer. The process focusses on three things: Defects Variability The customer If variation can be reduced, then there is less chance for defects to occur. Six sigma in statistical terms: The process in variation can equal half of the design tolerance. Allowing the mean to shift as much as 1.5 standard deviations from the target. Lean: The elimination of all non-value-added activities. (waste): Unnecessary steps or activities Rework Waiting time Unnecessary movement of people or material Excess inventory Find the source and permanently eliminate it Lean Facilitators: Empowered employees Cross-trained workers Flexible equipment Efficient layouts or floor space Standard processes Just-in-time delivery Rapid setup/changeover Lean Principles + Six Sigma Methodology Lean tools for reducing cycle time, more emphasis on six sigma We will not put into our establishment anything that is useless." Henry Ford Sr.* Example: delivery Lean will streamline your processes by eliminating nonvalue added steps and waste and reduce your average order time to four days, let's say. Although these improvements certainly will help reduce variability to some degree, Lean will not achieve the significant improvements needed in this case. Six Sigma experts will do that by applying statistical approaches to reducing defects and bringing the process steps within control. The result is it now your order time is on average, four days plus or minus one Lean addresses visible problems and processes one they can easily be seen like inventory, or material flow or late deliveries. Six sigma is concerned with problems that are less visible, like variability and performance that can be caused by errors and defects. UNDERSTANDING SIX SIGMA DEFINE When Motorola introduced the six sigma, they did not include the define step. They used four steps methodology: DMAIC - Define: added by General Electric (they faced problems implementing 6σ in their company) Measure Analyze Improve Control Determine what the project is What it should accomplish Motorola used six sigma only to production problems. General Electric applied it to support functions and services Defining tools 1. Conduct process mapping: understand what the project entails and what is not going to be included in the project 2. Outline excepted accomplishments: from the project and the metric you’ll use 3. Develop financial measurements: calculate the excepted financial bnefit (cost reductions, revenue increases) => finance agreeing in the beginning of your project, that if you accomplish your goal, it will result in this estimated benefit. 4. Define the problem: the project usually focuses on a symptom, such a particular product defect. Always keep the customer in mind Begin with problems that the customer believes are critical Critical to quality CTQ Anything that’s impacting the relationship with the customer should come first in determining Six Sigma projects. MEASURE If you can’t measure something, you can’t understand it. Understand, two aspects of measurements: - What to measure How to measure The DATA to measure, where is it? Who can help you to find it? Is it accurate? Classical mathematical expression: Y = f(x) The input you need (x), to determine the output you’re looking for (y) Determining Throughput The number of units that can be produced by a production process within a certain period of time - Utilization rate Yield (rendement): scrap rate, rework rate => historical DATA Process time Measurement Considerations Data collection methods Operational definitions: everyone agrees on how the terms are defined Measurement Tools - Data collection: as efficiently as possible Cause and effect diagram (fishbone) Process mapping: the functional relationship between your performance standard and your data Value stream mapping: distinguish value added activities from those that add no value to the process Process control charts: show the performance process as it relates to the established specification limits. Process capability charts: provide information about the variability of a process Histograms: give you historical data about critical performance aspects of the process Pareto charts: high to low ranking of the performance categories ANALYZE You can’t find the solution to a problem until you truly understand why you are having the problem in the first place. Why are you having the problem? Make sense of all the DATA collected so far and use analysis to find the source of the problems. Understand How the existing process works How the process should work Process mapping considerations Use process mapping to drill down to even more detail in the process. Consider such elements as: - Time (activities that are slowing down the total process time) Coast Yield Capacity Start to identify how the process should work => Find specific areas to eliminate complexity. Review DATA Look at DATA your already formatted in control charts, capability charts, histograms and pareto charts Seek out trends and anomalies. The FIVE WHYS technique: continuing to ask why until you identify the root cause of a problem. Analyzing Tools - Scatterplots: graph two variables against each other to determine if there is a relationship Time series graphs: plot a variable on a timeline to see if any patterns emerge Analysis of variance: it compares the distribution and variance of different data samples IMPROVE Implement a change that will resolve the problem and improve the performance measure. Improvement tools Brainstorming and communication Generate a list of possible solutions to the problem. Gathering ideas => evaluate the ideas one by one => determine the most favorable. Implement it! => effectively communicating with everyone involved with the change Get support from stakeholders, process owners and six sigma experts. CONTROL What enables you to have a continuous improvement organization. Put in place tools and procedures to make sure the solutions are maintained, and the change is everlasting. - Checklists Monthly review meetings Document updates Training Include guidance about how to monitor process performance. - Mistake prevention: implementing a procedure that makes it difficult to cause an error (example: enter DATA in a certain format) Mistake proofing: implementing a procedure that does not allow someone to continue if a mistake is made Document the gain realized from the improvement: comparing output DATA of the old and the new processes. DESIGN FOR SIX SIGMA DFSS / DFL(EAN)SS Business strategy for executing important projects that requires significant design changes. Helps to ensure that your new product will meet those customers needs and that the processes can meet Six Sigma capabilities. Transform customer needs into business requirements, in order to create new processes, new services, and new products. Design for Six Sigma uses the methodology of DMADV - Define (identify the process and clearly define the issues to be addressed) Measure (measure the critical to quality attributes) Analyze (analyze customer requirements as you develop a concept for your new process) Design (specify the details of the new process, review your progress, and approve its FV) Verify (develop a working prototype, test it and create a plan for implementing the process) Quality Function Deployment QFD An approach that assists the design, manufacturing, and marketing of a new product and its related process. Other names: DMEDI (define, measure, explore, develop, and implement) UNDERSTANDING LEAN LEAN METRICS Eliminate anything that does not provide value. James Womack and Daniel Jones => 1990’ book on Toyota’s lean manufacturing approach They outline 5 key principles on this approach to value: - Determine value for the specific product: determine your performance metrics Identify the value stream for that product: applying process mapping tools, you can determine the steps that add value to your product and the steps that do not Make value flow without interruptions: applying the principles of Lean and their problemsolving tools, you eliminate those non-value-added steps Let the customer pull value from the manufacturer: just-in-time manufacturing: Produce only what is needed TO SATISFY CUSTOMER DEMAND. Pursue perfection: this is the foundation for continuous process improvement Process mapping in one of the key tools of the Lean philosophy, it’s the first step to understand the process by drawing a picture of it. Distinguish value-added-activities from the others: LEAN PERFORMANCE MEASUREMENTS (metrics) Lean + Sig Sigma - Waste Cycle time Inventory => Tools of Lean are not based in statistics, so when variability is the cause of the problem, Lean project managers will call in a Six Sigma expert for assistance. MANUFACTURING METRICS Improved customer service Better use of resources Reduced inventory Higher product quality FIVE SS Define a system for organization and standardizing, they come from Japanese terms that stand for: Sort: Ensure that each item in a workplace is in its proper place, if the item is not needed, remove it Set in order: Arrange materials and tools so that they are easy to find when needed Shine: Keep the work area clean, important from safety perspective Standardize: Establish formal procedures to ensure all steps are performed correctly and consistently Sustain: Continue the standardized process through effective training and communication practices Standardize A big part of this principle applies to machines. Lean advocate a concept called cellular design in which the equipment is arranged in a U shape layout. Five machines arranged as a work cell can effectively be maintained by three operators. As compared to five operators in a straight-line layout. (Cross-training the operator) Application of visual control: if a machine is down or a part is defective, there is an indicator in plain sight of all the employees => correction action can be taken immediately JUST-IN-TIME Henry FORD: the father of just in time in the USA He did not believe in using Warehouses. He recognized that transportation was a critical factor for success, so he owned a private network of railroad cars and trucks to ensure smooth delivery of materials. Allows inventory to be maintained at minimal levels, thus reduction costs and increasing flexibility within the system Work is not started into the factory, until there is actual or forecasted demand for the final product This is controlled by a KANBAN SYSTEM: Kanban means sign or signal => uses a basic communication device. (Often just a simple card to notify each workstation when more inventory is needed) JIT considerations: Requires an effective delivery system Dependent upon standardized work processes TOTAL PRODUCTIVE MAINTENANCE TPM Preventive and corrective maintenance procedures => Keep the factory running when needed. TPM ensures: - Machine will not break down unexpectedly - Scheduled maintenance completed in a timely manner Minimize equipment down time and maximizing equipment availability Reduce the time and the cost of performing some machine setup (schedule maintenance or change the tool configuration to make a different product) Eliminating non-value-added steps and standardizing maintenance procedures. QUALITY AT THE SOURCE Quality is doing it right when no one is looking – Henry Ford No inspection if done right. Just as Six Sigma, mistake proofing is an important element of quality at the source. The Japanese term is Poka-Yoke: Foolproof => Procedures are put in place to make sure a mistake is not made and then passed on the next station. Quality at the source benefits - Throughput time decreased Quicker delivery to customers Just-in-time delivery CONTINUOUS IMPROVEMENT If you’re not getting better, you’re getting worse – Pat Riley, former NBA coach. Lean tools help with the reduction of waste and wasteful activities. The Lean expression is Kaizen. Kaizen Philosophy: You’re not trying to make the process perfect; you are trying to make it a little better. Continuous Improvement Approach - Operating practices and procedures Total involvement Training Kaizen Blitz: Expedited improvements made under tight deadlines Continuous improvement: Approach in both Lean and Sig Sigma; Kaizen and the control phase of the Six Sigma DMAIC methodology. IMPLEMENTING LEAN SIX SIGMA LEAD THE PROJECT Leadership and learning are indispensable to each other – John F. Kennedy Strong leadership + learning from experiences = SUCCESS Lean Six Sigma Success Criteria Leadership from top: leadership must communicate the strategy and demonstrate their support in their daily activities Skilled team members: this begins with the project leader, in both six sigma and lean Supporting infrastructure: your project’s success is directly dependent upon a pool of experts and applying lean tools, Six Sigma methods and project management skills. CONTROL THE PROJECT If everything seems under control, you’re not going fast enough – Mario Andretti Initiating Planning Excecuting : Monitor and Control Closing Leadership Responsibilities - Assignments Team coordination Performance Effective communication APPLY LEAN SIX SIGMA TO SERVICES - A slow process is usually caused by too much ‘work in process’ 80% of the delay is caused by 20% of the activities Only allow the complexity the customer is willing to pay for Analyze the activity with the Pareto 80/20 rule Use your Lean Six Sigma tool set to eliminate non-value-added steps Reduce variability in the value-added steps and drive out complexity LEAN SIX SIGMA FOR SUPPLY CHAIN Causes of inventory issues Poor forecast of demand Supplier problems Capacity issues Transportation company These projects need a cross-organizational approach, using experts from your company and also from key partners in the supply chain. Successful projects should be replicated throughout the company and its supply chain Replication is the key to success
