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Chapter 13 - Tools for process improvement. This chapter presents the following content: the deming cycle, the seven QC tools, Flowcharts, check sheets, histograms, cause-and-effect diagrams, pareto diagrams, scatter diagrams, control charts,…
Chapter 13 Tools for Process Improvement The Deming Cycle Act Plan Study Do Plan (1 of 2) Define the process: its start, end, and what it does Describe the process: list the key tasks performed and sequence of steps, people involved, equipment used, environmental conditions, work methods, and materials used Describe the players: external and internal customers and suppliers, and process operators Define customer expectations: what the customer wants, when, and where, for both external and internal customers Determine what historical data are available on process performance, or what data need to be collected to better understand the process Plan (2 of 2) Describe the perceived problems associated with the process; for instance, failure to meet customer expectations, excessive variation, long cycle times, and so on Identify the primary causes of the problems and their impacts on process performance Develop potential changes or solutions to the process, and evaluate how these changes or solutions will address the primary causes Select the most promising solution(s) Do Conduct a pilot study or experiment to test the impact of the potential solution(s) Identify measures to understand how any changes or solutions are successful in addressing the perceived problems Study Examine the results of the pilot study or experiment Determine whether process performance has improved Identify further experimentation that may be necessary Act Select the best change or solution Develop an implementation plan: what needs to be done, who should be involved, and when the plan should be accomplished Standardize the solution, for example, by writing new standard operating procedures Establish a process to monitor and control process performance Key Idea Deming Cycle The Deming cycle focuses on both shortterm continuous improvement and longterm organizational learning FADE Focus Analyze Develop Execute Juran’s Breakthrough Sequence Proof of the need Project identification Organization for breakthrough Diagnostic journey Remedial journey Holding the gains 10 Other Tools for Process Improvement Kaizen Blitz PokaYoke Process Simulation Key Idea Kaizen Blitz A kaizen blitz is an intense and rapid improvement process in which a team or a department throws all its resources into an improvement project over a short time period, as opposed to traditional kaizen applications, which are performed on a parttime basis PokaYoke (MistakeProofing) An approach for mistakeproofing processes using automatic devices or methods to avoid simple human or machine error, such as forgetfulness, misunderstanding, errors in identification, lack of experience, absentmindedness, delays, or malfunctions 35 Three Levels of Mistake Proofing Design potential errors out of the product or process – Eliminates any possibility that the error or defect might occur Identify potential defects and stopping a process before the defect is produced – Requires time to stop a process and take corrective action Find defects that enter or leave a process – Eliminates wasted resources that would add value to nonconforming work, but clearly results in scrap or rework Common PokaYoke Examples (from John Grout’s PokaYoke Web Page) Key Idea Process Simulation Process simulation is an approach to building a logical model of a real process, and experimenting with the model to obtain insight about the behavior of the process or to evaluate the impact of changes in assumptions or potential improvements to it Engaging the Workforce in Process Improvement Technical skills Shared vision Behavioral skills Key Idea Engaging the Workforce Compared to the technical tools for gathering and analyzing data, the “soft skills”—those that involve people—such as project management and team facilitation, are more difficult to teach and learn Skills for Team Leaders Conflict management and resolution Team management Leadership skills Decision making Communication Negotiation Crosscultural training Skills for Team Members Effective meetings Shared decision making Rules for Effective Meetings Use agendas Have a facilitator Take minutes Draft the next agenda Evaluate the meetings Adhere to the “100mile” rule Variables Check Sheet for Length of Logs in a Sample of 95 Trees 400 but under 700 Specification =700 700 but under 1000 1000 but under 1300 1300 but under 1600 1600 but under 1900 20 35 18 Specification=1900 1900 but under 2200 Number or defective cards due to major causes Illegible source document Torn card Data too light on card Offpunched card Warped Card Wrong Character Transposed numbers 68 60 100.0 98.5 92.7 88.3 82.4 45 30 41.2 15 Cumulative percent of major causes of defective cards (c) Bar Two CauseandEffect Diagram for Airline Ticket Errors Method (printing) Material (Ticket Stock) Quality Age Density Carbon Speed Supervision Ability Attention to detail Personnel Paper Training Type Age Frequency Airline Ticket Errors Maintenance Tension adjustment Machine Print quality SCATTER DIAGRAMS Various plot patterns in scatter diagrams y y y x x x Positive correlation Positive correlation may be present No correlation y Negative correlation may be present y x x Negative correlation .. .The? ?Deming Cycle Act Plan Study Do Plan (1? ?of? ?2) Define? ?the? ?process: its start, end,? ?and? ?what it does Describe? ?the? ?process: list? ?the? ?key tasks performed? ?and? ? sequence? ?of? ?steps, people involved, equipment used, ... needs to be done, who should be involved, and? ?when? ?the? ?plan should be accomplished Standardize? ?the? ?solution,? ?for? ?example, by writing new standard operating procedures Establish a? ?process? ?to monitor? ?and? ?control? ? process? ?performance... Key Idea Engaging? ?the? ?Workforce Compared to? ?the? ?technical? ?tools? ?for? ? gathering? ?and? ?analyzing data,? ?the? ?“soft skills”—those that involve people—such as project? ?management? ?and? ?team facilitation, are more difficult to teach? ?and? ?