Root Cause Analysis Tools, Tips and Tricks
Presented by: Sean Banayan Presented on: 8th June 2016
Sean Banayan
• Business Improvement Manager, Etel Limited • [email protected] • +64 27 511 9212 • LinkedIn Qualifications
• Master of Mechanical Engineering, Auckland University of Technology, NZ • PRINCE2 Practioner, APMG Australasia, NZ • Six Sixma Black Belt Certified, Aveta Business Institute, USA • Lean Manufacturing Operations Management, Aveta Business Institute, USA • TQM(Total Quality Management), Aveta Business Institute, USA • ISO 9001 Management Systems, Telarc, NZ
And…
•Have learned the Japanese thinking behind Lean and its successful application across a range of industries in Lean Japan Tour, Shinka Management, Australia Agenda
•Definition •Direct Cause vs. Root Cause •Data Driven Decisions •Data Collection & Visual Control •Clarify the Problem •Quality & Data at Source •Basic Problem Solving • Practical Example •Visual Control •Problem Description •Problem Solving Steps •Identifying the Direct Cause • Fishbone (Cause & Effect Analysis) •Identifying the Root Cause (5 Why) •Sustain & Share Best Practice •Questions Definition
Root Cause Analysis (RCA) is:
•A method of problem solving used for identifying the root cause of faults or problems.
•Is the fundamental breakdown or failure of a process which, when resolved, prevents a recurrence of the problem.
•It is a systematic approach to get to the true root causes of our process problems. Direct Cause vs. Root Cause Direct Cause
•It does not prevent its recurrence within certainty.
• Its only as good as a Band-Aid
•Usually blames someone Direct Cause vs. Root Cause Root Cause
•It is a proven source of the Direct Cause
•It will prevent recurrence of the Direct Cause
•It does not attribute blame to anyone. It looks for failure in the system, or process. Root Cause Sample
Machine that stopped because it Investigation shows that the machine overloaded The investigation proceeds further and finds overloaded and the fuse blew because it had a bearing that wasn't being that the automatic lubrication mechanism sufficiently lubricated had a pump which was not pumping sufficiently, hence the lack of lubrication.
Investigation of why the shaft was worn discovers that the Pump Cover which prevents metal scrap getting into the pump has been damaged. This enabled scrap to get into the pump, and damage the shaft. Investigation of the pump shows that it has a worn shaft. Data Driven Decisions Reason for choosing the problem
• Background information or KPI’s
• Effect on you or your group
• Links to higher level goals
• Customer identified Data Collection & Visual Control
Gather data and use facts • Record what is happening
• Manually gather information
• Grasp the situation before trying to fix it Data Collection & Visual Control
Collect DATA on defects, changes, incidents and other Key Performance Indicators (KPI’s)
Display the DATA as graphs to display combination of standard or target with current situation Supplier Issues Defects per month (%) for 2016 - 2017 3.0%
2.5%
2.0%
1.5%
1.0%
0.5%
0.0% Clarify the Problem
Category Department Level of & Type Importance Level of Urgency
Employees & Shift Level of Impact
Problem Breakdown Problem Prioritisation
Breakdown the initial Problem Perception to “one problem you can solve”. This should be the one which has the largest overall impact. Quality & Data at Source
•Quality is built-in to each process – Never send Quality defects to next process
Process 1 Process 2 Process 3 Process 4 Quality Check Data Gathering
Process 1 Process 2 Process 3 Process 4
Quality Check Quality Check Quality Check Quality Check Data Gathering Data Gathering Data Gathering Data Gathering Basic Problem Solving
• A problem goes into the Problem Solving funnel
PROBLEM Root Cause Fix STATEMENT
• Then leaves with a Root Cause Fix Basic Problem Solving
Initial Problem Description – Explain the problem
Fishbone Analysis 5 Why Investigation
PROBLEM ROOT CAUSE FIX STATEMENT
Follow Up Check Standardisation Share Best Practice Basic Problem Solving (Practical Example)
Please note – This is a training simulation
A problem has occurred in Fabrication department!
A number of jobs have failed final quality inspection due to incorrect build
We will work through this problem using some basic problem solving tools during this training presentation Visual Control (Practical Example)
Quality
MONTH/YEAR: Sep-15 AREA: FABRICATION
DATE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
OK NG >
DATE > 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 5 4 3
Defects 2 1
KEY - Where Defects Found Final Inspection Test Bay Other Dept Own Dept
No. of defects found during month
Defect Category 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Incorrect Part Position
Incorrect Plasma Cutting
Incorrect Folding
Not to Drawing Problem Description (Practical Example)
We are going to use this example from our Quality Balanced Score Card in Fabrication
So, what was the Problem Description….?
… Jobs failing fabrication inspection due to incorrect build…(Not to Drawing) Problem Solving Steps (Practical Example)
Now that we have a clear Problem Description, we are going to work through the following steps –
• Identifying the Direct Cause 1
• Applying a short term immediate action (Band-Aid) 2
• Identifying the Root Cause 3
• Applying a long term Root Cause Fix 4
• Sustain & Sharing Best Practice 5 Identifying the Direct Cause
First we must identify the Direct Cause and implement a short term immediate action (band aid)
It usually means we have to add more cost to our process by adding activities such as more inspection etc.
This is a very reactive way of working, but we need to do it until a Root Cause to the problem can be found.
We can use a Data Analysis graphs to look at a lot of different breakdowns to guide us to what can possibly be directly causing the problem. Root Cause Analysis Problem Solving Describe Describe the problem Quality Defects in Fabrication Clarify Clarify the size of the problem 16 Farbrication Defects 14 0 5 10 15 Feb-15 12 Fabrication Error 10 Jan/15 CARS in Fabrication 8 Leaking Welds Dec/14 6 Oil Leak Defect Inspection in Nov/14 4 Fabrication Welding Quality 2 Oct/14 0 Operator error Sep/14 Missing ID Aug/14
Welding Pole FABRICATION ERROR BREAKDOWN "WELDED IN WRONG POSITION" BREAKDOWN Splatter mounting Base hold down Door locking 2% bracket brackets Missing ID lifting lugs brackets 5% 4% Welded 2% 5% 5% Wrong M8 set screws on Excessive Weld Parts the HV door. Splatter 11% 5% 5% Missing Welds 11%
Welded in Wrong Oil Leak Position 13% 55%
Internal locating Parts Missing brackets 6% 71% Fishbone (Cause & Effect Analysis)
This is a good Team brainstorming event which helps to bring lots of ideas forward, regarding the Direct Cause of the Effect, in a short period of time
Use your Problem Solving Template – Write down lots of ideas that could be causing the problem in the head of the fish Enter your Problem Quality Check Lack of Welder’s Neglecting to Method Training check Description in METHOD MAN No Std Method No Procedures for the head of the of Positioning Attention to Details Checking Parts fish
IncorrectEFFECT Position (Problemof Internal LocatingObserved) Bracket Torches to Wrong check inside Tools tanks Measuring Tools MATERIAL MACHINE Drawing Not Clear
Key Point – No Idea is a Bad Try to group your ideas into the correct categories Idea! Fishbone (Cause & Effect Analysis)
Get the Team to vote on what they believe are the most likely direct causes of the problem in the head of the fish. This can be done by placing a tick on the idea
PNo Std PMethodP QualityP Drawing is of Positioning P Check P P unclear Method P P METHOD P MAN P No procedure for checking parts P Incorrect P Position of Internal Locating Bracket
Torches to Wrong check inside Tools tanks MATERIAL P MACHINE Measuring Tools Direct Cause Drawing Not Operators do not have Clear standard way of positioning the Internal Locating Brackets Fishbone – Direct Cause
• Remember the importance of CAPTURING DATA?
P Let’s enter that into our Problem Solving Template
• The next thing we must do is put a short term immediate action in place to act as a band aid whilst we find the Root Cause
• What could we do? Talk to the Operators? Re-train? More inspection? Manager to check that the job is correct every hour?
P Update your Problem Solving Template with your short term immediate action (band aid)… Problem & Containment Action
Also document the Problem Description and Short Term immediate Paction into the Problem, Cause, Countermeasure Sheet on the Board
September Fabrication
Re-train the operator & ask Internal Locating Bracket Q A 07 Jun quality inspector to double not in correct position check Identifying the Root Cause
• So, we have our Direct Cause ‘No Standard Procedure for Positing the Internal Locating Bracket’…
• …we can use a tool called 5 Why to drill further into the Direct Cause to uncover the Root Cause of the problem
• It is called 5 Why, but you don’t need to ask “Why” 5 times, you can use as many or as little as you like! 5 Why Example
Direct Cause of problem – No Standard Method of Positioning Part
•Why No Standard Method of Positioning Part? – Because operators don’t follow instruction of the drawing •Why operators don’t follow instruction of the drawing? – Because not all drawings are up to date. •Why aren’t the drawings up to date? – The Operators never feedback to engineers for drawing updates. •Why operators never feedback to engineers for drawing updates? – Because there isn’t a formal process to capture the issues and assign corrective actions against a time based plan. This is the Root Cause – If a countermeasure is applied here, it should completely eliminate the problem 5 Why – Root Cause
• Now we have our Root Cause – ‘No formal process to capture the issues and assign corrective actions against a time based plan’…
P Let’s enter that into our Problem Solving Template
• The next thing we must do is put a Long Term preventive action in place at the Root Cause level to eliminate the problem completely – This will replace the short term immediate band aid we put in earlier!
• What could we do?
P Update your Problem Solving Template with your Long Term Root Cause preventive action… Make sure you put a completion date! Root Cause & Fix P ?Now, let’s write the Root Cause & Root Cause fix action into the Problem, Cause, Countermeasure Sheet on the Board
September Fabrication
No formal process to capture the Implement a Formal Process to Internal Locating Bracket not in Re-train the operator & ask Q A 07 Jun issues and assign corrective capture the issues… J.Smith 19 June correct position quality inspector to double check actions against a time based plan
Don’t forget to enter the Person responsible for carrying out the action… & If they aren’t there at the time, please let them know! Direct Cause Vs Root Cause
Let’s have a recap on the differences between Direct Cause & Root Cause
DIRECT CAUSE ROOT CAUSE O Reactive P Preventive Direct Cause often assigns blame to P Root Cause does not blame anyone – The Opeople failure will always be in a system or process If a countermeasure is implemented at the P If a countermeasure is implemented at the ODirect Cause, it will not prevent a future Root Cause it will prevent a future recurrence recurrence of the Direct Cause O Usually requires a short term containment P The Root Cause is the proven source of action that is costly in time or resources the Direct Cause Sustain & Sharing Best Practice
•Standardise Successful Processes by documenting in instruction sheets, train members and confirming. •Why do we not standardise in the beginning?
Company’s Ideal State
Standardisation in the beginning before finding the Root Cause
Standardisation After finding the Root Cause
Process Questions