Lean Learning – DMAIC

Welcome to the Lean Learning Series on DMAIC

The Lean Learning Series is a series of sampled notes from my course content on a learning journey to a University of Limerick Masters in Quality Management (Lean Innovation)

DMAIC

A well-structured improvement methodology that provides a roadmap from the definition of the problem to the implementation of the solutions that address the underlying causes.

DMAIC is one of the most widely used improvement models. It provides the structure to drive your project ideas to success.

DMAIC Stage	Purpose
Define	Validate the opportunity and define the boundaries and goals of the project.
Measure	Collect data to establish the current state. This provides insight into what is actually occurring today.
Analyse	Interpret the data to establish cause and effect relationships.
Improve	Create solutions that target the confirmed causes.
Control	Create procedures to make sure that advances or gains can be maintained.

Tollgate Reviews:

Tollgate reviews occur after each major phase of the DMAIC process. They are a critical stage in each process phase because the ongoing project is linked back to the defined corporate targets.

During tollgate reviews, the appropriate levels of management, master black belts, and champions have an opportunity to:

Listen to the team present their work

Ask questions to maintain focus on the priorities of the organisation
Ensure the project is on track
Evaluate the ability of the team to achieve its objectives
Provide guidance to the team
Identify any organisational barriers to project success and workarounds for these issues
Undertake critical timing checks to maintain the project schedule

1 The Define Phase

The Define phase provides the team with the opportunity to clarify the goals and refine their understanding of the potential financial value of the project. It is important to determine who will do what portion of this work in your organisation. You should aim to:

Define the magnitude of the value of this opportunity in a given value stream
Provide an estimate of the scale of resources required
Develop a plan for how the project will be implemented using DMAIC

Define Phase Tools

The tools you will use the most in this phase are:

The Project Definition Form (PDF)

The SIPOC diagram

The PDF captures key information relevant to the project, such as the problem statement, scope, assumptions, resources, and schedules.

The SIPOC diagram provides a process view of how your company goes about satisfying a particular customer requirement. This methodology sometimes provides the first view of the full process sequence, unlike your historical silo-based approach.

SIPOC stands for:

Supplier: The entity that provides whatever is worked on in the process

Input: The material or information provided
Process: The internal sequence
Output: The product or service being sent to the customer

Customer: The next step in the process or the final customer

The SIPOC diagram usually takes shape during the Define phase, but its impact is felt throughout the rest of the improvement project.

Define Phase Tollgate

In the Define tollgate review meeting, your project team meet with appropriate senior management members to review the project.

This review should focus on:

Any modifications to the project definition

Evidence that confirms the value opportunity

Plans for the Measure phase

2 The Measure Phase

In this phase, you gather the data that describes the nature and extent of the problem. The data collection tools used in this phase will be used to measure improvement in later phases.

Measure Phase Tools

You can select from a broad range of data and process tools, including those outlined in Table 2.3.

Tools	Examples
Creativity Tools	Brainstorming Nominal Group Technique
Documentation Tools	Process Mapping Lead time sheet Cycle efficiency sheet
Data Collection and Display Tools	Check sheets Gauge repeatability and reproducibility (R&R)
Variation Tools	Run charts Control charts Process capability document
Focus and Prioritisation Tools	Pareto charts Cause-and-effect matrix FMEA

Measure Phase Tollgate

The Measure phase is one of the most variable stages and this is particularly evident at the tollgate review. There is no standard order for choosing the techniques your team must use. They must apply their own rational and expertise to select the most appropriate tools for the project.

The review must address the logic that your team pursued in their decision on what data to collect and where this data has taken you. In the pursuit of this knowledge, the review must address the following questions:

Where did you get the data?
Can you explain your measurement system?

What have you learned from your data charts?
Can you show me your cause-and-effect diagram?

Can you extrapolate the cause in the data you are collecting?

Why did you decide to collect that particular kind of data?

3 The Analyse Phase

In the Analyse phase, you should have accumulated a significant amount of data from the previous phases. The objective of this phase is to make sense of the data and identify the cause and effect relationships that produce the objective of your project.

You need to develop the knowledge that will help your team use its time in the Improve phase most effectively and develop process changes that address the underlying cause of the project problem. The aim in this phase is to explore the relationships or interactions between the input and output variables.

Analyse Phase Tools

Analysis tools are often used on historical data. While historical data can be problematic, you can still use it to find clues to help you determine potential causes of problems.

In an experiment I undertook in the UK, the historical data was compromised due to machine maintenance issues. Often data collected by another person has a greater chance of being corrupted. In my experience, if you cannot guarantee the quality of the historical data, you should gather your own data. There are many powerful analysis

tools that you can use to collect high quality information.

These tools include:

Casual analysis tools

Scatter plots

Analysis of variance (ANOVA)

Regression analysis

Time trap analysis

Design of Experiments (DoE)

Analyse Phase Tollgate

The Analyse phase tollgate review focuses on linkages between the causes and the data you are collecting and asks questions such as:

What cause is your team going to target in the improvement phase?
Why did you focus on this cause?

What other potential causes did your team investigate?
What data do you have that targets the cause of your project problem?
What data indicates that addressing the identified cause will have the desired impact on the targeted improvement measure?

4 The Improve Phase

During the previous phases, you and your team thought creatively about the problem you are trying to improve. In the Improve phase, you need to shift from thinking broadly to a focused and practical mindset. You now know the causes, what specific changes you can make in the process to counteract these causes, and what methods are required to achieve the desired effect.

Improve Phase Tools

Of all the phases in the DMAIC process, the Improve phase uses the broadest mix of Six Sigma tools:

Setup reduction

Process mapping

Pull systems

DoE
Total productive maintenance

Mistake proofing

Kaizen

Queuing methods

Four-Step Rapid Setup method

Improve Phase Tollgate

The Improve phase tollgate pursues the logical links between problem causes and effects and discusses the implementation of the solution

During the review, the following questions are addressed:

What countermeasures did your team develop?

How did you decide which ones to implement?

How did you know that these measures would affect the causes confirmed in the Measure phase?
What happened when the countermeasures were put into practice?

5 The Control Phase

The purpose of the Control phase is to capture and maintain the gains made until new technology and data show that there is a more optimised process. Your team must address a method of handing off what you have learned to the process owners.

Control Phase Tools

In the Control phase, the tools are all about implementation, how to document the new procedures, and what data must be collected to monitor performance. In many cases, your team will be using tools used earlier in the DMAIC process (for example, control charts), but the key is to switch to ongoing monitoring.

Control Phase Tollgate

This tollgate is both a formal completion of the project and a forum where key players like the process owners or key managers can see what they need to do to sustain optimum operational capability. Four key elements of the review are: