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Problems Solving Techniques

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Problems Solving Techniques

  1. 1. Reliability Engineering 1
  2. 2. 2 Problems Solving Techniques Presented by:- Eng. Mohammed Hamed Reliability Engineering
  3. 3. 3 Content 1. Brainstorming 2. Fault-Tree Analysis 3. Why Why Technique & Fishbone Diagram 4. Case Study: Identifying the RCFA 5. Pareto Analysis 6. Continuous Improvement PDCA Cycle Reliability Engineering
  4. 4. 4Reliability Engineering
  5. 5. 5 Brainstorming- A Downpour of Ideas Brainstorming is a well-known technique for generating a large number of ideas in a short time period. To encourage ideas, no idea should be critiqued or commented when offered. Each idea should be listed and numbered, exactly as offered on a flip chart. Expect to generate at least 50 to 60 ideas in a 30 minutes brainstorming session. Reliability Engineering
  6. 6. 6 Brainstorming rules: 1. Do not comment on, judge or critique ideas as offered. 2. Encourage creative and offbeat ideas. 3. A large number of ideas is the goal. 4. Evaluate ideas later. When the brainstorming session is over, the ideas should be reviewed, similar ideas combined, and ideas that do not seem to fit eliminated. Reliability Engineering Brainstorming is a group problem-solving method. It taps people creative ability to identify and solve problems, and brings out a lot of ideas in a very short time. Because it is a group process, it help builds people as human beings. For example, brainstorming encourages individual members to contribute to the group and to develop trust for the other members.
  7. 7. Reliability Engineering 7 What is needed for brainstorming? 1. A group willing to work together You may feel it is impossible that the group you work with will never be a team. However, brainstorming can be a key to build a team! Furthermore, it is a great tool for the group which is already working together. Who should be included in the group? Everyone who is concerned for the problem for two reasons: the ideas for everyone who concerned with the problem will be available for the brainstorm. Second, those people can take an active part in solving the problem. In that way they can be got to support the solution.
  8. 8. Reliability Engineering 8 2. A leader The main roles of the leader are: • Provide some guidance so that brainstorm will produce ideas • Control over the group to keep them on track. • Encourage people’s ideas and participation. • Put the personal goals aside for the benefit of the group. 3. A meeting place A place where there is no interruption or distraction. In some plants, groups use a foreman office, an area on the production floor, or even a conference room.
  9. 9. Reliability Engineering 9 4. Equipment Flipcharts, markers, and white boards. How does a brainstorm work? • Choose a subject for the brainstorm. • Make sure that everyone understand what the problem or the topic is. • Each person is to take a turn an express one idea. If someone can’t think of anything, he or she says “pass”. If someone thinks of an idea when it is not his turn, he may wright it down on a paper and use it at his next turn. • Write down each idea exactly as expressed. • Make sure to write all ideas and don’t reject any. • Encourage wild ideas, they may trigger someone’s else thinking.
  10. 10. Reliability Engineering 10 • Hold criticism until after the session. • The main goal is quantity and creativity. • A little laughter is fun and healthy but don’t overdo. It is O.K to laugh with someone but not at them. • Allow few hours or days for further thoughts (if needed). The first brainstorm on a subject will stimulate people to start thinking, but an incubation period allow mind to release more creative ideas and thoughts.
  11. 11. Reliability Engineering 11 Example: Brainstorming Session This group include five people: Samy, the leader; Farouk; Mohammed; Gamal, the recorder, and Ahmed. Since they have been meeting for only a short time and the members have not had much experience with brainstorming, the leader has to do most of the work of keeping them on track. As the group gains experience, other members should begin to share the work of the leadership. Samy: I think it’s time to brainstorm for causes of defective capacitors. Gamal, since you are good at flip chart, could you help us there? Gamal: Yes of course. Samy: Let us put a 15 minutes time limit on the session. And don’t forget the rules: We will go around from person to another, one idea at time. Don’t worry if your idea sound strange. After all, even if your idea is a wild one, it may stimulate somebody else. No evaluations. We will have plenty of time afterward to look at the ideas. Ok are you ready? (Everybody agrees.)
  12. 12. Reliability Engineering 12 Farouk, your turn. Farouk: Vendor (Gamal writes down, VENDOR). Mohammed: I have seen dents in some of them. And I think that a dent on the outside means something breaks or gets squeezed or some how messed up inside….. Samy: Mohammed, you are saying “dents”. Is that right? Mohammed: No, I mean dents show us there is a problem inside. Samy: Can we abbreviate it to read: “Dents show inside problem”? (Mohammed nods “O.K” Samy: Gamal, it’s your turn.
  13. 13. Reliability Engineering 13 Gamal: I think I will pass this time. Ahmed: The leads to the capacitor sometimes don’t get soldered well. So that makes it look like a defective capacitor. Gamal: How do I write that? “Soldering of leads”? Ahmed: Yup that’s O.K. Samy: My turn. I will build on Farouk’s idea of “vendor”. May be its only on of them that is really the problem and not all of them. Gamal write “One Vendor” Farouk: Seems to me the shape of AX12’s is the problem. They remind me of the toilet seats cover. (Much Laughter). Samy: Let’s get back to the subject. Farouk, may have something there. So Samy write “Shape of AX12’s”.
  14. 14. Reliability Engineering 14 Encouraging ideas: priming the pump again If the brainstorming session seems to slow down, the leader may suggest piggybacking. Piggybacking is building on others’ ideas. For example, if one of the team members has suggested the vendor as a cause of the problem, another one might say “one vendor” not all of them could be the reason of the problem. Another technique is to suggest opposites. For example, too much & too little. Prodding Techniques Sooner or later the downpours of ideas in the brainstorm dries up. What do you do to get it going again? Or what do you do with the silent member who doesn't participate?
  15. 15. Reliability Engineering 15 Dealing with the silent member When a member of the group doesn't speak up, the best way to deal with this is to be patient. Sometimes a person will be quite for a meeting after meeting then he will open up. It will be then very exciting, so give this persons a time. May be he/she will be quite, but will serve the group with some other ways. A simple effective method to bring the silent member, is to remind the whole group that when each person’s turn comes in the brainstorm, he or she just says “Pass” if not ready with an idea. That gets people of the hock but it also breaks the sound barrier. They hear their own voices and participate by saying “Pass.”
  16. 16. Reliability Engineering 16 The direct question is another method, but you must use it with care. Something like” Mohammed, you know the process well, do you have a suggestion or input here?” The second session After the initial brainstorm and sometime for further thinking, it’s a good idea to have another session to capture more ideas. These ideas come into mind as the group member think about the problem and consider what was said in the first session.
  17. 17. Reliability Engineering 17 Two ways to handle the second session: 1. Gather all group together and give them a time limit of 10-12 minutes for additional ideas. The same rules applied as in the first session. 2. Post the brainstorming sheets in the area of the workplace so that it will allow people who work in the same area to contribute even if they are not a regular members of the problem-solving group. In that way they feel they are not left out. Completing a brainstorm How do you make sure that brainstorming has covered all possible causes of a problem?
  18. 18. Reliability Engineering 18 Sometimes the solution lies in a search lab, where only a high trained expert has a chance of digging it out. Often, so, the solutions are right on your doorstep. Even if you don’t solve the problem right away, you can make sure that you have covered all the general areas of possible causes. Make a list of the general areas, and make sure that your group or team has examined every one of them. Such a list would include a number of subjects. There are some major factors that go into an operation: machine, method, material, environment, and people. Machine include: the type of the machine, the maintenance, and the setting. Materials are the elements that come to the process, whether they are raw material, sub- assemblies, components, or partially processed materials. Method concerns the process itself.
  19. 19. Reliability Engineering 19 Environment is important too, humidity, dust, and other climate problems that may affect the process. Finally, the Person doing the job. Factors connected with the person could be training, eyesight, and level of skills. Other general areas may also apply to the problem. Such as money, management, and other errors.
  20. 20. Reliability Engineering 20 Difficulties with brainstorming and what do you do with them You are stepping on my turf! It will be hard for one of the group members to be suspected that he is the reasons of this problem. For example, the design engineer is attending the session, and the cause of the problem came out to be in the design process. Train your team, and develop them. It is necessary to explain that we are not here to blame anyone. And we are sometimes blind with our problems so we need others to look on it. We tend to see only a part of the problem that’s why the causes may be hidden. It is a matter of prospective.
  21. 21. Reliability Engineering 21 Criticism Build a positive environment in the group. Criticize problems not people. Make sure that ideas not persons are evaluated. Make sure that mistakes are not publicized and never appear in anyone personal life. The difficult member Some members are difficult to deal with in the group. They talk too much, they get off track, they criticize people not ideas or they shoot down ideas. How do you deal with him? Be firm but friendly. Talk to him privately and explain how his way is distracting the group work. Give the difficult member a special job to do for the group. Don’t fight him. When he gets the group off track, re back the conversation to the normal topic gently. Usually difficult members became the strongest support of the group, or they leave.
  22. 22. Reliability Engineering 22 Fault-Tree Analysis Is a method to increase the reliability of the product and find the potential causes of a problem to prevent the product failure. Building a fault tree analysis FTA 1) Identify a top failure 2) Brainstorm basic contributors to failure 3) Link contributors to the top failure  Determine which combination of contributors is needed to cause the top failure. (Ask: How many of the inputs are needed to cause the top failure? )  Link the contributors to the top failure.  Each contributor (cause) can be given a weight depend on the occurrence so we would know which failure is likelihood to occur.
  23. 23. Reliability Engineering 23 Fault-Tree Analysis Smoke detector does not detect smoke Alarm not sounded Smoke not detected Alarm not sounded No power at alarm Defective alarm Broken wire Defective solder joint Defective ionization chamber No power at ionization chamber No power at control box Defective control box Ionization chamber cracked Defective solder joint Broken wire Ionization chamber blocked Vent blocked Dust blocked
  24. 24. Root Cause Analysis Approach Prepared by: Eng. Mohammed Hamed 24Reliability Engineering
  25. 25. 25 5 whys It was originated in Japan. Japanese people believe that by asking 5 whys you can figure out the root cause of the problem and find the solution. However, it doesn’t have to be 5 it can be 7 or 8. Toyota does not have a six sigma program. Six sigma is based on complex statistical quality analysis tools. It is a surprise for people to realize how Toyota has achieved this level of quality without the use of six sigma for quality. Most of problems don’t call for complex statistical analysis, but instead require detailed problem solving. This requires a level of detailed thinking and analysis that is all too absent from most companies in day-to-day activities. Reliability Engineering
  26. 26. 26 Level of Problem Countermeasure There is an oil on the shop floor Clean up the oil Because the machine is leaking Fix the machine Because the gasket has deteriorated Replace the gasket Because we bought gaskets made of inferior material Change gasket specifications Because we got a good deal/price on those gaskets Change purchasing policy Because the purchasing gets evaluated on short-term cost saving Change the evaluation policy for purchasing agent Why? Why? Why? Why? 5 whys is a method to pursue the deeper, systematic causes of a problem to find correspondingly deeper countermeasures Reliability Engineering
  27. 27. 27 Toyota Practical Problem-Solving Process Initial problem perception (large, complicated problem) POC Countermeasure Evaluate Standardize Clarify the problem The real problem Locate area point of cause Direct cause Cause Cause Cause Cause Grasp the situation Cause investigation Why? Why? Why? Why? Why? Reliability Engineering
  28. 28. 28 Q1: Why did the customer not buy the product? A: The salesperson did not persuade him to buy. Q2: Why did the salesperson not persuade the customer to buy? A: The salesperson was not good enough. Q3: Why was the salesperson not good enough? A: The sales person has not been trained in sales. Q4: Why has the salesperson not been trained in sales? A: It was not considered necessary. Q5: Why was training not considered necessary? A: Sales are only a small part of the job. Example Reliability Engineering
  29. 29. 29 Problem Using a fishbone diagram while brainstorming possible causes helps you to focus on the various possibilities. Some useful categories: Fishbone Diagram Reliability Engineering
  30. 30. 30 The main problem is entered in the nose. The bones originally had only “4Ms”. Once all problems were reduced to one of the four: man, machine, material, or method. Eventually, measurement was added to highlight how critical it is to have an understanding of the reliability and accuracy of the measuring system. Environment was added to make people consider the location of an equipment and the impact of its surroundings on the operation. Design and instruction can also be a good reason to add. Reliability Engineering
  31. 31. Problem Identification: Production decreased to low level Plant Capacity: 450ton/day 31Reliability Engineering
  32. 32. 32Reliability Engineering
  33. 33. Problem with plant production performance Transportation of raw material problem Production labor problem Others Breakdowns 33Reliability Engineering
  34. 34. Breakdowns issue Environmental downtime issue Electrical issueOther external factors Equipments downtime (unplanned maintenance) 34Reliability Engineering
  35. 35. Plant downtime report 35Reliability Engineering
  36. 36. Equipments breakdown issue Machine 4 Machine 3 Machine 1 Machine 2 Machine 5 Machine 6 36Reliability Engineering
  37. 37. Equip code Critical Equip description Total Downtime hrs (average) Downtime frequency MTTR (hrs) Percentage 1 Centrifugal Fan 16 5 3.2 44.80% 2 Pump station 2 Motor 6 2 3 16.80% 3 Granulator Drum 4 2 2 11% 4 Feed Belt Conveyor 3 2 1.5 8.40% 5 Recycle Belt Conveyor 2.5 1 2.5 7.00% 6 Bag Filter 2.5 1 2.5 7% 7 Burner 1 1 1 2% 8 Belt Conveyor 0.5 1 0.5 1.40% 9 Belt Conveyor 0.2 1 0.2 1.40% 10 Bucket Elevator ---- ---- ---- ---- Priority Identification (Top Failures) Equipments downtime monthly report: 37Reliability Engineering
  38. 38. Pareto Analysis A problem solving tool that breaks data down into manageable groups and identifies the greatest opportunity for return on investment. The analysis is based on the Pareto Principle, also known as the 80:20 Rule. Simply stated, the principle says that 20% of a population will cause 80% of the problems associated with the population 0.00% 5.00% 10.00% 15.00% 20.00% 25.00% 30.00% 35.00% 40.00% 45.00% 50.00% 0 2 4 6 8 10 12 14 16 18 38Reliability Engineering
  39. 39. 39 Pareto diagram uses bar graphs to sort problems according to severity, frequency, cost, nature, or source and displays them in order of size in order of size to show which problem is the most important. Its probably the most often used statistical tool in Toyota. Reliability Engineering
  40. 40. Motor Foundation Bearing FDE Bearing FNDE Casing Man Hole 40Reliability Engineering
  41. 41. Machine 1 failed Motor electric failure Power off Machine unplugged Overloaded 41Reliability Engineering
  42. 42. Overload Process problem Electrical problem Cleaning problem Mechanical Vibration problem 42Reliability Engineering
  43. 43. Mechanical vibration problem Bent Shaft Bad maintenance Bearing failed Unbalance Bad fixation with the base Misalignment 43Reliability Engineering
  44. 44. Unbalance Rotor problem Bad balancing Others Scale accumulative 44Reliability Engineering
  45. 45. 45Reliability Engineering
  46. 46. Dust accumulative Incorrect balancing Cleaning issue Design Problem Problem in sandblasting efficiency Bad operation Process problem 46Reliability Engineering
  47. 47. Scale 47Reliability Engineering
  48. 48. 48 System Illustration Diagram (1) Dryer Drum (3) Fan (4) Bag Filter (2) Cyclone Dust settling Suction Reliability Engineering
  49. 49. Repair the coating for body of the cyclone Repair the pneumatic system for closing and opening the gates Get new discharge valve Real Photo 49Reliability Engineering
  50. 50. 50Reliability Engineering
  51. 51. Electric motor failed Electric cable problemPower off Machine unplugged Motor overheated 51Reliability Engineering
  52. 52. Motor overloaded Motor overheated 121⁰C Cooling fan Motor located in bad environment Bad preventive maintenance 52Reliability Engineering
  53. 53. Motor miss- installed Motor overloaded Shaft damaged Motor Shaft Vibration problem Machine problem 53Reliability Engineering
  54. 54. Shaft damaged Misalignment Incorrect fit Incorrect tolerance Bearing failed 54Reliability Engineering
  55. 55. Bearing failed Insufficient lubrication Excessive clearance Mounting problem Grease contamination Failed motor bearing Incorrect bearing type Incorrect lubricant usage 55Reliability Engineering
  56. 56. Use the proper tools for mounting and train the maintenance crew Preventive Action 56Reliability Engineering
  57. 57. Plan each step and understand the outcome expected at each point. Do the task as planned. Check that is the outcome is as expected “Audit”. Act –find out what is going wrong . Then repeat the cycle. Plan what you are going to do to put it right. Do make the corrections. Then continue the rest of the cycle, repeat the loop as necessary. Plan-Do-Check-Act. PDCA Cycle. Continuous Improvement Problems Solving Process: 1. Define the problem. (Plan) 2. Breakdown the problem into manageable pieces. (Plan) 3. Identify the root causes. (Plan) 4. Set the targets. (Plan) 5. Provide countermeasures & select proper solution. (Plan) 6. Implement the solution. (Do) 7. Check the outcomes and the impact. (Check) 8. Define what went wrong, repeat the cycle, adjust, and standardize. (Act) 57Reliability Engineering
  58. 58. Reliability Engineering 58 Each step is a PDCA toward the target
  59. 59. 59 Eng. Mohammed Hamed Ahmed Soliman The American University in Cairo Email: mhamed206@yahoo.com m.h.ahmed@ess.aucegypt.edu Tel: +201001309903 References: Liker, J. K. (2003). Toyota way. New York: MacGraw-hill. Steven, S. (2012). Strategic lean mapping. New York: MacGraw-hill. Reliability Engineering
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