Tuesday, 12 March 2013


What is Lean? 

The core idea is to maximize customer value while minimizing waste. Simply, lean means creating more value for customers with fewer resources. 

A lean organization understands customer value and focuses its key processes to continuously increase it. The ultimate goal is to provide perfect value to the customer through a perfect value creation process that has zero waste. 

To accomplish this, lean thinking changes the focus of management from optimizing separate technologies, assets, and vertical departments to optimizing the flow of products and services through entire value streams that flow horizontally across technologies, assets, and departments to customers. 

Eliminating waste along entire value streams, instead of at isolated points, creates processes that need less human effort, less space, less capital, and less time to make products and services at far less costs and with much fewer defects, compared with traditional business systems. Companies are able to respond to changing customer desires with high variety, high quality, low cost, and with very fast throughput times. Also, information management becomes much simpler and more accurate. 

Today I am going to explain some different Lean tools and the principles to integrate into Six Sigma framework. 

Increasingly, organizations that use Six Sigma are making an effort to integrate Lean into their existing process-improvement framework. For many, combining Six Sigma’s focus on process quality and Lean’s emphasis on turn-around time results in more high-impact, quick-hit projects. To gain this advantage, however, organizations must face a difficult obstacle: integrating Lean without creating ripples in the existing Six Sigma structure. If the Lean introduction is not done properly, it can lead to more pitfalls than successes. 

With a structured approach, though, it is possible to merge Lean into a mature Six Sigma framework. Five Lean tools and principles are particularly applicable for this purpose: 

1. Value Stream Mapping

In the Analyze phase of a DMAIC project, a value stream map can be created that shows the flow of materials and information, and categorizes activities into three segments: value enabling, value adding and non value adding. The focus of this tool is on identifying and eliminating the non-value added activities in each process step and reducing the wait time between consecutive steps wherever possible. Value enabling activities, however, cannot be totally eliminated from a system. Instead, they can be sub-classified into value adding and non-value adding activities, allowing those value enabling activities that are non-valued added to be eliminated. These eliminations help make a process more compact – a benefit in process improvement projects aimed at reducing variation. This tool also can be a part of a Kaizen cycle, incorporated within the Analyze and Improve phases.

2. Takt Time

Takt is a German word that can be roughly translated as “beat.” Takt time is the rate at which a completed project needs to be finished in order to meet customer demand. For processes involving cycle times, such as manufacturing or incident management, the as-is cycle time can be captured in the Measure phase. Then, during the Analyze phase, the cycle time can be compared with existing service level agreements (SLAs). If a mismatch exceeds the tolerance, improvements would be needed to match the cycle time with the takt time for the system. 

3. Ishikawa (Cause-and-Effect) Diagram and 5 Whys

In the Analyze phase, the absence of concrete statistical data sometimes can make the identification of a root cause difficult. In those scenarios, the 5 Whys – asking “Why?” five times – along with a cause-and-effect diagram, can make the task more manageable. The 5 Why’s tool also can help uncover the process dynamics and the areas that can be addressed easily. 

4. Heijunka (Load Balancing)

A Japanese term, Heijunka refers to a system of production designed to provide a more even and consistent flow of work. This principle can be incorporated in the Design phase if the root cause analysis during Analyze points to bottlenecks in the process. Load balancing can be used to introduce a pull in the system rather than letting it operate on push – thus alleviating the bottlenecks. Efforts for introducing a level load balance in the system also automatically reduce inventory. If takt time principles are used while designing the system, it would help ensure a level load balance. 

5. Poka-yoke (Mistake Proofing)

A Japanese phrase meaning mistake proofing, poka-yoke can be used to tune process steps and also when designing a new system altogether with DMADV (Define, Measure, Analyze, Design, Verify). A combination of an Ishikawa chart and Pareto analysis can be useful in Analyze in listing the major issues plaguing the as-is process. During the Improve and Design phases, the possibilities for eliminating a major cause of errors can be explored by improving or redesigning the system to avoid error-inducing scenarios. 

Through the initial push from the leadership team, combined with learning aids on Lean tools, the LSS approach would be widely accepted throughout the organization. This will boost both the tangible benefits and the turn-around time for process-improvement projects at your company. 

Here you have an interesting Lean Project example at a Medical Imaging Firm. 

— Source: Lean Enterprise Institute, iSixSigma 


No comments: