Faculty of Engineering, Department of MAME
University of Windsor, Canada
Semester: Fall 2018
Lean Manufacturing & Process improvement
Prof. Sardar Asif Khan
Malay Mistry (104904064)
A case study is based on improving process capability, product quality and productivity through Six sigma methodology to reduce the process cost and increase in net profit of company. Researcher took an Electronic manufacturing company name Elin Appliances which produce many electronic products. Company is suffering from higher product price in market. Company was using simple techniques to reduce the production cost. In Six sigma we can use DMAIC process and other tools to reduce the cost and achieve the goal of Cost reduction through operational excellence.
In this company researchers shown the current map. By analyzing we can see that company having problem of higher price of product and this was due to higher production cost of product mainly due to poor quality, poor process control and defects. After research they concluded some areas which need improvement and one of the main is Production waste. In year 2006-2007 they have loss of 100k Euros due to poor productivity and production wastes. They want to eliminating waste by improving productivity and reducing all type of waste. For that they had applied Six Sigma to achieve the result by using DMAIC method.
Company mainly focus on 3 major wastes which are Over Production, Over Processing and Defects and try to eliminates form roots.
Method and Tools used
Company has adopted six sigma methodologies at every stage and try to implement the possible improvements. Company was following DMAIC process for this project. First, they have defined the problem of poor productivity and defects in Define stage.
After that they following the M stage mean Measure. They start to collect the current data of every stage to find the root cause and opportunity of improvement. In measure stage they have done as below hierocracy.
1. The Flow through M-Phase-
2. Develop process measures
3. Collect Process data
4. Check data Quality
5. Understand Process behavior
6. Baseline Process Capability
They have also taken data from assembly line to identify the throughput rate by process mapping. Below chart shows the data of Throughput rate in steam iron and Juice mixer assembly line.
Researcher has identified many major point where they found opportunity of improvements. For doing 5-why analysis they have classified following non-value-added activities.
In Toaster cooling stage
In Sieve matching and jar matching
In Iron cooling stage
In Preheating stage
In Packaging stage
In Pop up testing
Researcher has done Why analysis on non-value-added activities and find root cause for each of the activities and that root cause need to take as goal and try to eliminating issue. The question ask for 5 times gives you main root cause. Table shown in below diagram.
In measure phase, Company has taken data of cycle time of every machine and stage of work. Which help to understand the problem in work cycle, also help to simplify the process as per TAKT time and find the possibility for line balancing. They have created chart Time vs Activity. Activities are divided in small part so minor waste can be seen.
In Analyze phase, Researcher has done analysis on data collected and plotted in graphs, first major non-confirming and variation are targeted and analyze. Pareto graph is plotted for period of Jan’07 to July’07 as the root cause analysis activity shown in fig.
In pareto chart is clearly shown the 2 factors have 80% effect on overall causes. Mainly component quality and component un-availability affect the efficiency of production. Other factors are as follow Component not available, breakdown of machine, Kit not issued, Manpower issue and utility problems.
Analyze phase contains following steps
1. Determine potential root cause to measure
2. Analyze data using process stratification
3. Verify root causes with test data
This stage, All the major and minor root cause studied and fleshes out the root cause or causes of the problem.
Each problem statement is identified and analyze by meeting and brain-storming activities.
Forth one is Implementation phase
The Flow through implement phase-
• Assess risk using FMEA
• Design implementation plan
• Communicate to People
• Pilot solution and track improved performance
In this phase, all people need to work together to find the optimum and feasible solution for each root cause and uncover the problems which are identified in analyze phase. In this phase people of company form all the level put their mind in it, this is brainstorming. Researchers has done some testing and experiment of new ideas and successful result is the sign of Kaizen.
Below image shows the elements of Implementation phase
Some of the pilot batch run as trail run and measure and analyze phase is done again to check the satisfactory result as per goal. Budget and return on investment is also key elements it be consider while doing kaizen.
Some of high risk for solution is implement through FMEA. Below table shows the FMEA for current case study.
As seen in the first row, Conveyorisation has 2 failure mode breakdown and misalignment and they suggested recommended action such as proper design evaluation and release, Preventive maintenance plan and proper pilot. Such action leads to prevent failure and continuous workflow.
Last is Control Phase
Implement permanent control methods which are tested and verified
• Track and confirm improved long-term process capability
• Standardize control plan
• Identify leverage opportunities
• Validate final financial results
• Project handout
In this stage observations of improved method is taken and analyze as per plan and find the variation, this phase is long term till new implementation not come in use. In this case study the responsibility is given to respective member to observe and control the process.
KPI Dash board – The Process outputs to be monitored
Below chart shows the activity done in control chart. Productivity chart is Plotted
Manhour vs Time (Quarter) it’s clearly show the peak in curve with time, it’s the
proof of successful improvement in productivity and six sigma’s benefits.
Company has followed all phases of Six sigma and achieve their goal for productivity.
During the DMAIC process, Researcher has understood the current map and find the solution every root cause for every single problem and furthermore company has implement and sustain their improvements which result in Higher productivity, Lower defect, effective utilization of manpower and machine.
X and R bar chart shows that the variation is reduced and the parts are more accurate to dimensions. Also, down time is reduced leads to high machine utilization.
Main three wastes overproduction, over-processing, and defects are successfully eliminated. Higher productivity help to lower the cost of the process. Minor cycle time study and its improved results into an improvement from the root, for instance, RTV application process is repetitive and done by manually. After DMIAC process and improvement company make it automatic which increase the efficiency of the RTV process.
It also impacts on inventory as shown in the graph. Inventory ratio was 4 in the year 2004-05 but after implementation of six sigma in 8 year reaches to the 15. Higher inventory ration help decrease lead time and expense of the company.
Finally, all over the elimination of waste leads to higher profit and fewer wastes. Company gain in its financial budget and expenditure. The company reaches 5 times turnover around 95 crores in 2012 from 21 crores in 2004-05, after implementing Six Sigma.
IF I was Project Lead
This case study shows that, Researcher has used DMAIC methodology under six sigma which gives the positive result. If I was project lean I used “Value Stream Mapping”. This technique helps to you in every aspect for improvement. The electronic company has assembly line and its work on TAKT time as per customer order. Value-stream mapping is a lean-management method for understanding the current state and designing a future state for the series of events that take a product or service from its beginning through to the customer with reduced lean wastes as compared to current map.
Mainly over-production and over-process can be minimized by VSM. The company have many assembly lines and work stations. It can be merge and balance the cycle time by doing single flow. Such things are easy to identify from VSM. Company have problem in Inventory an overabundance of inventory which results in greater lead times, increased difficulty identifying problems such issue is solved by VSM
Here is an example of VSM
There is scope of improvement by doing process mapping, over-processing can be minimized by using such technique.
Also, there is 3rd waste is defects, I would prefer Process Capability. Process Capability analysis helps you how well your process meets specifications and provides insight into how you can improve a poor process. By lowering defect Company can achieve goal towards six sigma and net profit also increase.
Here is sample of process capability charts.
VSM, Process mapping and Process capability I would use to eliminate waste and defects. Other tools such as cause and effect diagram, 5’S, Kanban, QFD, SIPOC can be used to improve current scenario of company and achieve zero defect.
1)A Case Study on Improving Productivity by Reducing Operation Cost as Six Sigma Process Improvement by Elin Appliances
2) Class notes of Lean manufacturing / Process improvement by sardar asif khan (fall 2018)
3) https://www.isixsigma.com4) https://www.smartdraw.com5) https://en.wikipedia.org6) https://www.google.com