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5 Why Analysis. January 2, 2006. 5-Why Training Agenda. Where does 5-Why Fit within the PRR process Understanding of 5-Why Quick 5-Why Exercise as a group Critique Sheet 5- Why Examples Wrap Up/Discussion. 5-WHY. Where does it fit within the PRR process?.
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5 Why Analysis January 2, 2006
5-Why Training Agenda • Where does 5-Why Fit within the PRR process • Understanding of 5-Why • Quick 5-Why Exercise as a group • Critique Sheet • 5- Why Examples • Wrap Up/Discussion
5-WHY Where does it fit within the PRR process? • After a supplier has submitted an initial response and containment plan (Step # 2 in the PRR process), a detailed investigation is necessary to determine what caused the problem. Step # 4 (Supplier determines the root cause) requires a 5-Why analysis to help in identifying the root cause of the problem. • Going back to one of the elements within the Purpose of a PRR “to facilitate problem resolution”, 5-Why is the prescribed tool for determining the root cause of the problem to facilitate problem resolution.
Why Is the powerful question… own it!!
How Fast Should You Be Going? Speed Limit Strictly Enforced How Fast Are You Going? No Reaction Cause Reaction (Look at speedometer) Cause Reaction & Research (Look at speedometer; Search for speed limit sign) Power of Asking Questions
Power of Asking Questions Who are the best at asking questions to solve problems?
Children! Why? Power of Asking Questions …because they keep asking objective, open-ended questions until the answer is simple and clear When working with people to solve a problem, it is not enough to tell them what the solution is. They need to find out and understand the solution for themselves. You help them do this by asking open-ended , thought provoking questions.
Close-Ended: Structures the response to be answered by one word, often “yes” or “no”. Usually gives a predetermined answer. Example: “Did the lack of standardization cause the incorrect setup?” Open-Ended: Leaves the form of the answer up to the person answering which draws out more thought or research. Example: “How is setup controlled?” Close-Ended vs. Open-Ended Questions
Benefits of Open-Ended Questions • Requires thought • Promotes additional research • Enhances problem solving skills • Does not assume there is one right answer • Avoids predetermined answers • Stimulates discussion • Empowers the person answering In many circumstances, it is not only the answer itself, but the process by which the answer was determined that is important when asking an Open-Ended question
More Examples Example 1: “Did the lack of a PM system cause this tool to break?” (Close-Ended question, can be answered by a “yes” or “no”, gives the person a predetermined answer that PM is to blame) “What could have caused the tool to break?” (Open-Ended, probing question forces the person to think about all possibilities, not just PM) Example 2: “Would improving material flow help reduce lead times?” (Good question but it’s still Close-Ended, focuses the person on material flow as a means to reduce lead time. Is this the best improvement?) “What are some options on improving lead time? (Open-Ended, triggering more thought and research on all variables impacting lead time.) Example 3: “Is equipment capability causing the variation in your process? (Close-Ended, can be answered by a “yes” or “no”, focuses the person on equipment being the source of variation) “What could potentially cause variation in your process? (Open-Ended, triggering more thought and research, opens up possibilities of variation with man, material & method, not just machine)
5 Why Overview
5-Why Analysis Three Paths • 5-Why: • Specific problem: • Why did we have the problem? • Problem not detected: • Why did the problem reach the Customer? • System failure: • Why did our system allow it to occur?
5-Why Analysis Specific Detection Systemic
Root Cause Analysis Delco fuse box Insert example What tool do We use for this?
Grasp the Situation • Part I – Grasp the Situation • Step 1: Identify the Problem • In the first step of the process, you become aware of a problem that may be large, vague, or complicated. You have some information, but do not have detailed facts. Ask: • What do I know? • Step 2: Clarify the Problem • The next step in the process is to clarify the problem. To gain a more clear understanding, ask: • What is actually happening? • What should be happening? • Step 3: Break Down the Problem • At this point, break the problem down into smaller, individual elements, if necessary. • What else do I know about the problem? • Are there other sub-problems?
Grasp the Situation • Step 4: Locate the Point of Cause (PoC) • Now, the focus is on locating the actual point of cause of the problem. You need to track back to see the point of cause first-hand. Ask: • Where do I need to go? • What do I need to see? • Who might have information about the problem? • Step 5: Grasp the Tendency of the Problem • To grasp the tendency of the problem, ask: • Who? • Which? • When? • How often? • How much? • It is important to ask these questions before asking “Why?”
5-Why Analysis • Step 1: Problem Statement • Is the problem statement clear & accurate? • Is the analysis on the problem as the customer sees it? • Step 2: Three Paths • Are all three legs filled in? • Are there any leaps in logic? • Can you ask one, two, or three more Whys? • Is there a cause-and-effect relationship in each path? • Can the problem be turned “on” and “off”? • Does the path make sense when read in reverse? • Do the whys relate to the actual error? • Does the non-conformance path tie to design, operations, dimensional issues, etc.? • Does the detection path tie to the customer, control plans, etc.? • Does the systemic path tie to management issues or quality system failures?
5-Why Analysis • Step 3: Corrective Actions • Is there a separate action for each root cause? • Is it possible to implement each corrective action? • Do corrective actions require Customer approval? If so, how will they be communicated to the Customer? • Is there evidence to support verification of corrective actions? • Are corrective actions irreversible?If not, do actions address ongoing containment? • Is there a plan to standardize lessons learned across products, departments, etc? • Step 4: Lessons Learned • How could the problem have been foreseen? • How will information be implemented? • On the line or in the plant? • At the point of detection? • Cross functionally at the Supplier? • Other products/plants?
5-Why Analysis • Step 5: Overall • Are there gaps or “holes?” • Are there things missed or not documented? • Do corrective actions address actions the Supplier owns? • How many iterations of 5 Why Analysis have there been? • Who prepared the 5 Why Analysis? • One person? • Sales representative ? • Clerk? • The best answer is a cross functional team that understand the product and process!
The problem is stated through the eyes of the customer Problem The first why is the main cause The second why is what causes the main cause Therefore Etc. Why? Etc. • You have root cause if you • can demonstrate: • cause on, problem on • cause off, problem off Root Cause 5-Why Analysis
Problem Cookies taste really bad Cookies are undercooked Therefore Ingredients are wrong Why? Used goose eggs rather than chicken eggs Root Cause Recipe did not specify bird type 5-Why Example (Non-conformance)
Problem PPAP submitted late PPAP package not complete Therefore Validation testing not complete Why? Test lead time not considered No system to accurately assess lead times of all PPAP elements Root Cause 5-Why Example - PPAP Submittal (Non-conformance)
Problem PPAP submitted late Did not react to the target submittal date Therefore Did not know the target submittal date had passed Why? No requirement to follow-up on target submittal dates No standard system to manage PPAP submittal timeliness Root Cause 5-Why Example - PPAP Submittal (Detection)
Problem Did not meet the annual business plan goal of a 10% increase in sales Did not thoroughly evaluate market/competition Therefore Did not have adequate resources Why? Did not anticipate required resources Did not develop a plan as to “how” the goal would be reached Root Cause 5-Why Example - Business Plan (Non-conformance)
Did not meet the annual business plan goal of a 10% increase in sales Problem Did not know the goal was not going to be met Therefore Did not evaluate the status of the goal until December Why? Did not have alarms limits identified at strategic intervals (monthly, quarterly, etc.) Root Cause Did not develop a plan to monitor the status of reaching the goal 5-Why Example - Business Plan (Detection)
Flex Industries Case Study-Background • Jake Ryan is the Quality Manager at Flex Industries. Flex is a component supplier that manufactures metal stampings and light assembly products. The company has a reputation for supplying high quality parts on a consistent basis. Seldom has there been a customer complaint. Flex has Quality representatives called Customer Support Engineers (CSE’s) at every customer assembly plant. The CSE’s report any problems to Jake for investigation and follow-up. • At 7:00 a.m. this morning, Jake received a call from Janet, CSE at the Winding River Assembly Plant. Janet informed him that the customer had found five defective stabilizing brackets on second shift last night. She checked the remaining inventory and there were no defects in the remaining 326 pieces. The manufacturing sticker on the back of the brackets indicated that they were made by the second shift operator. Normally, the stabilizing bracket is fastened to the regulator motor with three rivets. The five defective brackets had only two rivets in them. The lower set of rivets on all five brackets was missing a rivet. This was the first time that the problem occurred.
Background GOOD BAD Jake set-up containment procedures at the plant warehouse to sort for discrepant materials. As of this morning, two more defective brackets had been found in the remaining 2019 pieces of inventory at Flex.
Cause Investigation • Jake went out to the floor to talk with the team leader of the two rivet lines (East and West) and the area quality assurance auditor. He informed Sam (the team leader) of the quality problem and asked him to identify the line which runs the stabilizing bracket assembly. Sam directed Jake to the East line which runs Winding River assembly brackets only. • At the East Line, he spoke with Judy (the QA Auditor for the area) and asked to see the quality log sheets. Jake and Judy reviewed the Nov. 11th log sheet and could not find anything out of the ordinary. He asked her to set-up in-house containment procedures to sort for any discrepant material in the finished goods area. • Next, Jake tried to locate the second shift operator whose clock number was on the defective parts. Since that operator was gone, Jake spoke with the current machine operator (Ben). He asked Ben about any recent difficulties with the rivet machine. Ben said that he hadn’t noticed anything out of the ordinary. Ben also mentioned, however, that there had never been any quality bulletins posted in the two years that this particular part has been running. • Jake decided to stay in the area to watch the machine run for a while. After about 15 minutes, he watched Ben dump rivets into the feeder bowl to prepare for the next run.
Cause Investigation • Shortly after restarting rivet operations, Ben walked over to another riveter and came back with a steel rod. Ben poked around the rivet chute and then continued working. Jake approached Ben and asked him about the steel rod. Ben replied that from time to time the chute gets jammed and he has to clear it out. This happens two or three times during a shift. He didn’t mention this in his earlier conversation with Jake because the problem has existed ever since he started working with this machine. The previous operator showed him how to clear the chute. All the rivet machines are like this. • Jake called the Machine Repair Department and asked that someone look at the rivet track. A slight gap in the track was found and removed, and Ben continued to work. • Two hours later, Jake got a call from Ben saying that the track was still jamming. As far as Jake could see, only rivets were in the bowl. Next, Jake looked into the rivet supplier containers. There was some foreign material in the blue container, but none in the red container. The label on the blue container showed that it was from Ajax Rivet, Inc., and the label on the red container indicated that it was from Frank’s Fasteners. Obviously, the foreign material was entering the rivet feeder bowl and jamming the track.
Cause Investigation • Jake called Maintenance and requested that the bowl be cleaned. He also added the cleaning operation to the preventive maintenance schedule on the equipment. He then called both Ajax Rivet, Inc. and Frank’s Fasteners. He asked about the cleaning procedures on the returnable containers. Frank’s did a full container purge and clean. Ajax just re-introduced the containers back into their system. When Jake asked why Ajax did not clean their containers, he was told that Ajax was not aware that such a policy was needed. • Upon further investigation, Jake learned that Frank’s Fasteners supplies other major automotive companies. Since these companies require that all returnable containers be cleaned, Frank’s instituted the purge as part of its practice for all customers. Ajax Rivet, however, depends primarily on Flex as its major customer. No such policy has ever been required of them.
Cause Investigation • Jake called the Material Control Department and requested that a container maintenance policy be drafted which would apply to all their suppliers. He also asked that a machine modification be developed to sense for the presence of rivets. Hopefully, this would error-roof the process. • Key Players • Jake Quality Manager • Janet CSE, Winding River Plant • Sam Team Leader, East Line • Judy QA Auditor, East Line • Ben Machine Operator
Generic Information for 5-Why Example: Regular Cola Soft Drink vs. Diet Cola • The plant received a PR/R from a customer. (We use 5-Why Analysis to answer every PR/R.) • The PR/R states that the customer received “Regular Cola in the right container (same for both products) with the Diet Cola label”. The order called for Regular Cola. • The plant has two identical lines that are capable of running either of our two products. The lines are located immediately beside each other. The only differences in the products are the syrup and the labels. • The plant runs both lines 24 hours per day. There are three shifts that run 7:00 a.m. to 3:00 p.m., 3:00 p.m. to 11:00 p.m., and 11:00 p.m. to 7:00 a.m. • The date code indicates that the defective product was manufactured at 3:03 p.m. • Defective product has been contained and sorted.
B O T T L I N G BOTTLES LIDS WATER INSPECT SYRUP LABELS Bottling Process Flow for 5-Why
Generic Information for 5-Why Real Example: “O” Ring Seal • The plant received a PR/R from a customer. (We use 5-Why Analysis to answer every PR/R.) • The PR/R states that the customer received “Mixed/Foreign Material in Shipment”. • The supplied part is an “O” Ring seal for oil filter. • A cutting operation produces the part to specified size. As the raw material (cylindrical component) goes through the cutting operation, the irregular end-cuts are removed from the station. • Cutting Station • Mat’l Flow
Missing o-ring on part number K10001J WHY? WHY? WHY? WHY? Parts missed the o-ring installation process Parts had to be reworked Why did they have to rework? Operator did not return parts to the proper process step after rework No standard rework procedures exist This is still a systemic failure & needs to be addressed, but it’s not the root cause. Is this a good or bad “Non-Conformance” leg?
Missing threads on fastener part number LB123 WHY? WHY? WHY? WHY? Did not detect threads were missing What caused the sensor to get damaged? Sensor to detect thread presence was not working Sensor was damaged No system to assure sensors are working properly This is still a systemic failure & needs to be addressed, but it’s not the root cause of the lack of detection. Is this a good or bad “Detection” leg?
A good 5-Why will answer “Yes” to the five PDCA questions: “A problem well defined is a problem half solved” ACT PLAN Standardize Understand the problem 5. Has a plan been identified to STANDARDIZE and take all lessons learned across products, processes, plants, functional areas, etc.? 1. Is the problem statement CLEAR and ACCURATE? 2. Has the SYSTEMIC root cause(s) been identified for all legs? CHECK DO Follow-up Execute the Plan 4. Has a plan been identified to verify the EFFECTIVENESS of all corrective actions? 3. Has IRREVERSIBLE CORRECTIVE ACTION(s) been implemented for ALL root causes?
WHY? WHY? WHY? WHY? WHY? Check 4. Track PM completion % to assure 100% conformance (C. Beckett) 6/1/03 Check 5. Check for burrs on threads for 60 days to verify c/a (M. Mendoeous) 6/1/03 - 7/31/03 Check 6. Track FTQ at stamping to monitor PM improvement (S. Boland) 6/1/03 Is this a good Corrective Action plan? Corrective Action w/ Responsibility Date Plan Fastener P/N 10001 would not assemble A Do 1. Replace worn tool (K. Jones) 6/1/03 Burrs on the thread 2. Begin conducting PM on all dies after every run, minimum 1 x / day, to collect history (L. Burg) 6/1/03 Do/Act Worn stamping tool 3. Assess & adjust PM intervals for all dies based on history & mfg recommendations (B. Clark) 7/31/03 Do/Act Tool exceeded recommended wear life PM interval not adequate Plan PM failure; No system to strategically set PM intervals A
5-Why Critique Sheet • General Guidelines: A.)Don’t jump to conclusions!; B.) Be absolutely objective. C.) Don’t assume the answer is obvious. D.) If you are not thoroughly familiar with the process yourself, assemble a cross-functional team to complete the analysis. • Step 1: Problem Statement Is the analysis being reported on the problem as the Customer sees it? • Step 2: Three Paths (Dimensional, Detection, Systemic) -Are there any leaps in logic? -Is this as far as the Whys lead? Can you still ask one, two, three more why’s)? -Is there a true cause-and-effect path from beginning to end of each path? Is there statistical data/evidence to prove it? ---Can the problem be turned off and on? -Does the path make sense when read in reverse from cause to cause? (e.g.—We did this, so this happened, so this happened, and so on, which resulted in the original problem.) -Do the why’s go back to the actual error? -Does the systemic path tie back to management systems/issues? -Does the nonconformance path ties back to issues such as design, operational, tiered supplier management, etc…? -Does the detection path ties back to issues such as protect the customer, control plans, etc…?
5-Why Critique Sheet (cont) • Step 3: Corrective Actions -Does each corrective action address the root cause from a path? -Is there a separate corrective action for each root cause? If not, does it make sense that the corrective action applies to more than one root cause? -Is each corrective action possible to implement? -Are there corrective actions that affect the Customer or require customer approval? How will they be communicated to the Customer? -Is there evidence and documentation to support the validity of the corrective actions? -Are the corrective actions irreversible? If not, are there corrective actions in place that address containment? • Step 4: Lessons Learned -How could this problem have been foreseen? -How will this information be implemented: a.) on the line or in the plant? b.) at the point of detection? c.) cross-functionally at the Supplier? d.) other product/plants? -Are there lessons learned for the Customer? • Step 5: Overall -Do there seem to be big holes where ideas, causes, corrective actions, or lessons learned are being avoided? -Where things are missed or not documented? -Do the corrective actions address the actions the supplier owns? -How many iterations has the supplier gone through so far in preparing this 5-why (It doesn’t happen on the first try!) -Who prepared the 5-why?
Problem Case Audit Standards • 5-Why Analysis: Green, Yellow, Red • G: Can follow logic and flow of all 3 legs of 5 why's. The legs all differentiate "What is the problem, why wasn't it detected, and what happened systemically." • Y: All 3 legs filled out, some leaps of logic, needs minor corrections to improve. • R: 1 or 2 legs missing, Leg 1 repeated as leg 2 or 3, not understanding what the different legs mean--typically missing what the systemic leg is. Poor answers on 2 or more legs.