Process Improvement (& Quality Engineering) Process Variability Reduction. Introduction. What is PVR? Understand variability, its impact and behavior.

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Process Improvement (& Quality Engineering) Process Variability Reduction Introduction Understand variability, its impact and behavior. Learn how to effectively apply PVR tools to reduce variability in
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Process Improvement (& Quality Engineering) Process Variability Reduction Introduction Understand variability, its impact and behavior. Learn how to effectively apply PVR tools to reduce variability in your work process. Understand your role in PVR. Be prepared to start PVR in your area. What is PVR? Process Variability Reduction or PVR is an approach to reduce variation in our transactional processes in a way that dramatically reduces the variation in our transactional outputs. Processes: Customer Service, Job Instructions, Pre-Press, Invoicing, Shipping, etc. PVR increases process stability, consistency, and quality 1 PVR Results Today Tomorrow Output Understanding Variation And Standard Operating Procedures Process View Supplier Inputs Process Output Customer 2 Understanding Variation All things vary - no two things are exactly the same. All variation has a source. The cause of poor performance is unmanaged sources of variation. We can manage variation by identifying and removing the source! Understanding Process Variability and Reducing Defects and/or Cycle Time :00 3:00 5:00 7:00 9:00 11:00 13:00 15:00 17:00 19:00 21:00 23:00 1:00 3:00 5:00 7:00 9:00 11:00 13:00 15:00 17:00 19:00 21:00 23:00 1:00 3:00 5:00 7:00 9:00 11:00 Time of Day Traditional View of Variation Cost of Variation $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ LSL Target USL 3 Therefore. Process Variation is the Enemy of Quality & Performance! Using Six Sigma - The DMAIC Approach Define the problem or issue. Measure the outcome. Analyzewhat is driving or causing the problem. Improve the process by acting on the information and confirming the outcome. Control the new process to maintain the gain. Shall see how to reduce process variation through Six Sigma Define 4 Simple PVR Define Tools Customer Interview Process Maps Standard Operating Procedures/Work Instructions Value added Analysis Spaghetti Diagrams Exercise: Paper Airplanes Form a team of 5 people Make 25 airplanes All team members must conduct at least one step in the construction process. The first team member to touch the plane (start the process) time stamps the plane. The last team member to touch the plane (stop the process) time stamps the plane. Exercise: Paper Airplane SOP 1. Fold the paper in half. 2. Fold the left wing in to the center of the airplane. 3. Repeat step 2 with the right wing. 4. Fold both wings out. 5. Extend wings for flight. 5 Look Downstream, work Upstream Inputs 2. Then Define the process intended to provide this X X X 3. The right efforts made here, by the right team will improve the process.. X 1. Start by Understanding what the customer wants X X Y 4...So that results show here Don t be insane by. Doing the same thing today that you did yesterday, and expecting a different outcome Albert Einstein Customer Interview Important information gathering technique to identify and understand customer needs. Able to ask follow -up questions to gather more complete and useful feedback. Fosters cooperative working relationships between customer and supplier. Must be well planned. Remember, customers can be internal or external 6 Customer Interview Suggestions Ask: What barriers do you face in doing? What issues do you encounter when? What are the main issues as they relate to? In an ideal world, what would you improve? Why is that true? Tell me more about that. Give me an example. Open-ended questions. LISTEN! Conduct the interview in a way that the person(s) being interviewed feel like the customer Airplane Customer What does the airplane customer want? What is their objective? Might knowing this give you any ideas on how you should build and fly your airplane? Simple PVR Define Tools Customer Interview Process Maps Standard Operating Procedures/Work Instructions Value added Analysis Spaghetti Diagrams 7 Process Map or Flowchart Visual description of the process. Identifies customers and suppliers. Used to identify process measures and key measures (discussed later). Points out discrepancies in the process. Points out inefficiencies in the process. Initiates standardization of procedures. Serves as a training tool. Who is the Customer? Customers Are Recipients of Products and/or Services Customer Internal External Internal Customers use our outputs for their processes. External Customers pay our bills... Who is the Supplier? Suppliers Provide Products and/or Services Supplier Internal External Outputs of Internal Suppliers are inputs to our process. We pay External Suppliers. 8 Process Map Example: Shipping (Xs) Inputs: Origin Destination(s) Delivery Time Weight Lane Selection Carrier Assigned Truck picks up at origin Carrier Selection Truck delivers at destination(s) Is this a: Want it to be, Believe it to be, or an Actually is map? Equipment available for specified ship/delivery date? yes no Cost Incured (Ys) Outputs: Cost CWT Using the Process Map There are usually 3 versions of each Process Map What you Want it to be... What you Believe it is... What it Actually is... SOPs Simple PVR Define Tools Customer Interview Process Maps Standard Operating Procedures/Work Instructions Value added Analysis Spaghetti Diagrams 9 Standard Operating Procedure (SOP)/ Work Instruction (WI) Written document that describes a process, and the procedure(s) we all agree to use to run the process. Includes critical people, policies, procedures, and plant. The life blood of TPVR. Writing SOPs/ WIs Process map the basic process. Process map main sub-processes. Write a detailed description of the work to be done, following the process map. All obvious sources of variability identified on the fishbone diagram should be addressed. Insert all information into the SOP/WI template. How did our airplane SOPs stack up? 1. Fold the paper in half. 2. Fold the left wing in to the center of the airplane. 3. Repeat step 2 with the right wing. 4. Fold both wings out. 5. Extend wings for flight. Do we need to create a new SOP?? 10 Simple PVR Define Tools Customer Interview Process Maps Standard Operating Procedures/Work Instructions Value added Analysis Spaghetti Diagrams Value Added Analysis There are usually 3 versions of each Process Map What you Want it to be... What you Believe it is... What it Actually is... To Be SOPs Value Added Analysis We often find many steps that are not value-added. Value-Added: Customer recognizes the value Changes the product Done right the first time 11 Value Added Example Value-added Analysis of Air Travel from NYC to Chicago Arrive Airport 1 hr before departure = 60 minutes Taxi from gate to runway = 10 minutes Flight to from NY to Chicago = 121 minutes Taxi from runway to gate = 10 minutes Wait at baggage carousel = 15 minutes Elapsed Time = 216 minutes Value-Added = 56% Non-Value-Added Activity Reduces Speed Analysing a Process Map for Non- Value Added Activities Validate the Process Map with a walk through Identify value-added and necessary steps Identify streamlining activities to improve process flow Develop to-be Process Map Validate to-be Process Map Develop implementation plan Implement changes (careful here) Approaches to identify To Be : Process Streamlining WHAT WHERE WHEN WHO HOW ELIMINATE COMBINE REARRANGE SIMPLIFY PLACES SEQUENCES PERSONS 12 Approaches to identify To Be : Cycle Time Add cycle times to Process Map. Include: Run Time time to actually perform the step Wait Time time unit sits waiting for movement to next step Queue Time time unit sits waiting for processing Changeover Time time to change from one unit to next unit Look for opportunities to reduce cycle time by eliminating steps, changing the sequence of steps, eliminating/minimizing movement between steps, etc. Necessary Steps A step may be non-value-added but necessary if: It is required by law, regulation, or contract It is required for safety, health, environmental, or ethical considerations EPA EEOC OSHA Simple PVR Define Tools Customer Interview Process Maps Standard Operating Procedures/Work Instructions Value added Analysis Spaghetti Diagrams 13 Approaches to identify To Be : Spaghetti Diagram Create a Spaghetti Diagram of the path taken by a unit and/or information as it travels through the process. Identify steps done more than once and long travel distances. 1, 8 2, 5, Summary of Define Variation is everywhere. Process Maps help us visualize the process steps and identify opportunities for streamlining the process, and removing variation. Standard Operating Procedures (SOPs)/ Work Instructions (WIs) describe the critical elements of a process so we can reduce variation in procedures. Other tools will be learned in the Analyze section to help us further identify and remove sources of variation. Measure I What To Measure 14 Types of Measures Key Measures - Metrics describing quality of the process output, as viewed by the customer. Tell us where we are versus where we should be. Process Measures - Metrics describing the inputs, steps, and/or components of the process. Help us determine how to get where we should be. Types of Measures Key Measures S C Process Measures Types of Measures Throughput Customer Time of Day Employee Location Defects Size Cycle Time Schedule Attainment Waste or Spoilage Cost Number of employees Proportion defective Number of errors Look at this list. Which are more likely to be Process Measures and which Key Measures? 15 Measure Tools Average Median Range Variability Ratio Describing Variation Average or Mean - tells you where the process is located. Median - tells you where the process is located. Range - the distance between the highest and the lowest points. Indicates spread. Variability Ratio - The ratio between the 1st and 3rd quartiles of data. Indicates spread. Average or Mean Sumof all the data points Average= Number of data points 82% + 20% + 16% + 14% + 12% X = = 28.8% 5 Indicates location of process. Reflects all the data values. Influenced by extreme values. 16 Measure Tools Average Median Range Variability Ratio Median Median 82% 20% 16% 14% 12% The center number after the data has been sorted in ascending order. The 50th percentile of the data (also Q2). Indicates the location of the data. Does not use all values in the calculation Robust to extreme values. Measure Tools Average Median Range Variability Ratio 17 Range 82% 20% 16% 14% 12% Range = 82% -12% = 70% The distance between maximum value and the minimum Value Uses only two data points. Influenced greatly by extreme values Measure Tools Average Median Range Variability Ratio Variability Ratio - Q1/Q3 VR is a number between 0 and 1. Is the ratio Q1/Q3 (the 25th and 75th percentiles). Indicates the amount of variation or spread existing in the process. The lower the number, the more variation. The higher the number, the less variation. Robust to an extreme value.# 18 Variability Ratio - Q1/Q VR = Q1 / Q3 = 7362 / 8611 =.85 Q1 Q2 Q3 Q4 Frequency Procedure for Determining VR Collect at least 30 points of data Sort from smallest to largest. Divide the total number of points (N) by four. This is the number of points in each quartile. Q1 is the largest number in the first quartile. Q3 is the largest number in the third quartile. Divide Q1 by Q3. This is the Variability Ratio, VR. VR Calculation Exercise Date Value 1/ / / / / / / / / / / / Date Value 1/ / / / / / / / / / / / Date Value 1/ / / / / / / / / / / / Date Value 1/ / / / / / / / / / / / VR Calculation Exercise Variabilit y Ratio Q1 = Q Variabilit y Ratio = 7721 Variabilit y Ratio = /2001 Version 1.3 Module 2 - Understanding Variation and SOPs Measure II Getting & Assuming Good Measures Transactional Processes often measure: Cycle Time Defects and/or defectives 20 Cycle Time The actual time needed to complete a step and move on to the next step in the process. A B Job Arrives at Step A at 8 am. Caution! Job Arrives at Step B at 9 am. Cycle Time = 1 hour Defectives & Defects A Defective unit is that which fails to meet customer requirements or standards. Late order, incorrect invoice, short-count, etc. A defect is any reason for such a failure Not filed correctly, incorrect line item, transposed numbers, etc. A defective unit can have more than one defect. Defects per Unit (DPU) Defects Per Unit (DPU) the average number of defects, of all types, over the total number of units produced. Unit is the item being processed order, invoice, form, plate, etc. DPU = (total defects) / (total units processed) 21 DPU Example During the month of July, 220 invoices were sampled before being sent to customers. Among the 220 invoices, a total of 344 line items were found incorrect (defects). Unit = Invoice DPU = 344 incorrect line items/220 invoices = 1.56 Measure II Tools Operational Definitions Sampling Measurement System Analysis Operational Definition A precise description of what is to be measured. What is to be measured. When it is to be measured. Materials, information, or equipment to be used to measure it. How it is to be measured. Who is to measure it. Used to remove ambiguity in measurement and improve data integrity no matter who does the measuring, the results are the same. 22 Measure II Tools Operational Definitions Sampling Measurement System Analysis Sampling It is not always possible or feasible to gather and analyze 100% of the data from a process. We can draw conclusions about the process through sampling. What Is A Sample? Collecting only enough individual data points from a process to determine the sources of variation. A fast, low cost way to describe a process. Population X X X X X X X X X X X X X X X X X X X X X X X X X Sample 23 Measure II Tools Operational Definitions Sampling Measurement System Analysis Sources of Measurement Error Data must be available and accurate Most measurement issues are controllable, and fall in one of the following categories: Data Unavailable Recording/Judgement Errors Keying Errors Legibility Errors Undefined and/or Poorly Defined Codes Poorly Designed Forms Minimizing Measurement Error Code unclear, recording/judgement errors and undefined codes Develop operational definitions Talk to each other; use across shifts Ensure everyone is identifying the same problem Legibility and keying errors Write neatly Do not assume that the data entry clerk knows what you are trying to say Training Over-communicate 24 Exercise: Do you know what time it is? Sample Process Measure Sample Process Measure Range Sample Invoicing CSR Average Range Range Sample Invoicing CSR Average Range At a glance, what can we say about this Invoice Cycle Time measuring system? A Simple MSA Index: 1) Estimate the measurement system variation. 2) Estimate the total observed variation. 3) Calculate the percent of total variation due to the measurement system. A Simple MSA Index σ MS Percent Measure Variation = σ obs - Where - Average of the Measure Ranges = And - σ MS σ obs Average of = the ProcessRanges MSA Exercise: Estimate Measure Variation 1) From the previous data, what is the average of the Measure Ranges (Invoicing v. CSRs)? R MS 1247 = = What is the measurement system standard deviation or σ? σ MS 62 = = MSA Exercise: Estimate Total Observed Variation 2) From the previous data, what is the average of the Process Ranges (Sample to Sample)? R obs 2265 = = What is the observed standard deviation or σ? σ obs 119 = = MSA Exercise: Compute the Index 3) Compute the percent of measurement variation to total observed variation? Percent MeasureVariation = Percent MeasureVariation = Percent MeasureVariation =.274or 27.4% 26 MSA Exercise: Compute the Index So how good is this measurement system? So So Summary Measures provide a baseline of where we are and show where we are going. Key measuresdescribe the process output. Process measures describe the process inputs and potential sources of variation. Measures describe the process location and spread. Average and Median measures the location. Range and Variability Ratio (VR) measure variation time. Defects and Cycle Time are the two most critical measures for PVR. Sampling can be used to represent the process. Measures can be improved with good measure procedures. Exercise: Paper Airplane Performance Identify and eliminate variation in making and flying paper airplanes: Standardize the paper and the design. Create a detailed Process Map of airplane construction. Streamline the process. Complete detailed SOP/WI Template. Construct airplanes using new SOP/WI. Measure cycle time and defects for each airplane. Record the data: airplane number, cycle time, number and type of defects Calculate the Median and VR. 27 Analyze Simple PVR Tools Simple PVR Analyze Tools Brainstorming Fishbone Diagram FMEA Pareto Chart Histogram Run Chart Check Sheet Scatter Diagram 5 Why s Brainstorming Display a clear question the group is considering. Ask the group to answer the question with silent writing. Collect the ideas from each group member, in turn, one at a time. No criticism or discussion Do not interrupt others Any individual may pass on any turn Record the ideas as stated for all to see. When everyone passes on the same turn, discuss the ideas. Clarify Combine similar ideas Identify common themes or categories 28 Simple PVR Analyze Tools Brainstorming Fishbone Diagram FMEA Pareto Chart Histogram Run Chart Check Sheet Scatter Diagram 5 Why s Fishbone Example: Order Entry People Machines Customers Don't Follow Instructions Don't Have Latest Form Copy Machine Not Available Don't Understand Sales Persons Computer Not Trained Forgot Phone Orders Order Clerks Not Trained Poor Work Conditions Order Form Fax Unreadable Misfiling Software Needs Updating Software Glitches Errors in Entering Orders Poor Layout Shortage Too Much Handwritten Data Entry Not Verified Price List Has Errors Customers Don't Have Latest Materials Accept Orders from Anyone Changes Marked in Pencil Procedures Modified from Waste Chasers: A Pocket Companion to Quality and Productivity. Conway Quality, Inc., Airplane Exercise: Use the Tools Brainstorm and Fishbone FMEA and Pareto Histogram and Run Chart Check Sheet and Scatter Diagram 5 Whys 29 Simple TPVR Analyze Tools Brainstorming Fishbone Diagram FMEA Pareto Chart Histogram Run Chart Check Sheet Scatter Diagram 5 Why s Prioritize Problems ( FMEA-like ) Prioritization will: Provide a Pareto-like list of the problems Guide team activities Guide the tracking of those activities Give a starting point of questions to ask and answers to find first We can use the priority calculation we used in the FMEA lecture! Prioritize Problems Problem Severity Frequency Detection Priority problem problem problem problem problem problem problem problem problem problem problem problem Simple TPVR Analyze Tools Brainstorming Fishbone Diagram FMEA Pareto Chart Histogram Run Chart Check Sheet Scatter Diagram 5 Why s Pareto Chart Shows the relative magnitude of a problem. Helps focus on the causes that will have the greatest impact if solved. Can provide multiple perspectives of the magnitude of the problem. Multiple levels can help to identify root causes and solutions. Pareto Chart: Plate Defects by Frequency 31 Pareto Chart: Plate Defects by Cost 2 nd Level Pareto Chart Reduced Payment Freight Bills C ount Percent 100 Contract Rate Disputes Def ect Count Percent Cum% 0 Rate Dispute Cla ss Canada Misc Or iginal Destinatio n Weight Reconci led Others Count Perc ent 0 0 Modified from The Memory Jogger II, Goal/QPC, 1994 Defect Count Percent Cum % A dv Carr ier Ful l Capacity Deliver y Mine Sites Min Charge NYC Mi sc Oth ers Common Pareto Metrics Frequency Cost Time Rate or Percentage Value ( ) Impact etc. 32 Pareto Chart Procedure Make a list of categories or problems to compare. Select a standard unit of measurement or metric. Gather the data on a Check Sheet or other form. Draw bars representing the magnitude of the unit of measurement for each category, and display in order of magnitude. Review and act on the information! Simple PVR Analyze Tools Brainstorming Fishbone Diagram FMEA Pareto Chart Histogram Run Char
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