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In the previous post, I outlined how lean projects can be manged through Plan-Do-Check-Act (PDCA) cycles. Here, I’ll be walking through an example.

Plan

This step includes drawing current value stream (VS) map in terms of processes (or activities), calculating processing times on the value stream, and analyzing for waste. After conducting some brainstorming, the PDCA team can list opportunities for removing such waste by reducing, re-organizing, realigning, training. Finally, we prioritize such opportunities start implementation with those with highest impact first.

In this example, a pizza shop takes orders for delivery over the phone and processes manually.  Customers complain about delivery time being long. Here is how the process works:

• The order taker writes down all order information (type of pizza, size, ingredients, ..etc.) as well as the address.
• Order gets verified by the manager before forwarded to the kitchen. In case of any missing information, the order taker calls the customer back for corrections
• Prepare pizza
• Pizza sits in queue before baking
• Bake, cut, package and label pizza
• Pizza waits in warmer for delivery
• Deliver pizza

The goal here is to eliminate all complaints due to “long delivery time”and increase customer satisfaction.

Times form the above value stream can be summarized as follows:

Lead Time: The time from the customer calling in until the pizza is delivered. In this example, the Lead time is 44 minutes.Value-Adding: All activities that add value to what the customer experiences / pays for. Those steps amount to 15 minutes which is about 34% of the lead time.

Delays / Waiting amounts to 8 minutes.

The PDCA team has conducted root-cause analysis to eliminate waste (and shorten delivery time). The team decided that the manual system for orders created delays and inefficiencies. So it was decided to implement a computerized system for entering orders and communicating them to the kitchen using computer monitors. Also, it was decided to hire an additional delivery driver. The future value-stream table is expected to look as follows:

Do

• Prepare and implement action plan for  computerized system
• After implementation, let the system run and stabilize
• Collect delivery times data again for measuring progress

Check

• Data analysis after implementation of plan show a reduction of  lead time by an average of 11 minutes. This is a reduction of approximately 25% of lead time.
• Complaints due to long delivery time were reduced by 60%.

Act

The updated  value stream after implementation will become the “current” for the next PDCA. As can be seen from the updated value stream table, delays due”waiting for oven space” and “waiting for driver” are still there and could be minimized or eliminated by coming up with efficient methods and creating additional capacity.

Mustafa Shraim

I recently co-authored an article summarizing a Six Sigma project. The article was about a Six Sigma project in e-mail marketing in which design of experiments was used.

The project did not exactly follow the Define-Measure-Analyze-Improve-Control or DMAIC as we know it. Instead, The headings of the DMAIC process were as follows:

• Define / Measure
• Measure / Analyze
• Improve
• Control

The Define/Measurephase includes some Plan-Do-Check-Act cycles in determining and verifying factors to be included. For example, checking feasibility of that certain level combinations can be run. When we move to the Measure/Analyzephase, we are actually collecting and analyzing data based on the experimental design . Sometimes we need to do preliminary analysis before we add more samples and conduct more detailed analysis.

The point is that smaller PDCA cycles are often within each phase and between consecutive phases. The phases of the projects are dynamic in nature and not static. In the end, each project is unique and so should be treated.