Comparing Six Sigma and lean manufacturing

You’ve probably seen our latest post about the role of maintenance in a lean manufacturing strategy. Today we’ll explore Six Sigma and how it’s both similar to and separate from lean manufacturing. So, what is the difference between lean and Six Sigma? Let’s find out.

What is Six Sigma?

We’ll start with a definition. Six Sigma is a set of methods and tools that help businesses improve product quality and production efficiency. This is done by finding process defects, determining their cause, and making improvements. For maintenance teams, it can be used to find and address weaknesses in maintenance workflows.

The Six Sigma philosophy sees anything that doesn’t meet the customer’s expectations as a defect. A defect could be a literal production defect in the manufacturing process or any variation in a customer’s experience.

What is the difference between lean manufacturing and Six Sigma?

Lean manufacturing defines different kinds of waste that can occur in the production process and aims to eliminate any and all forms of waste wherever possible. Six Sigma, in contrast, is focused on statistical analysis and uses the Define, Measure, Analyze, Improve, and Control (DMAIC) method to implement process improvement. Let’s take a look at each of these five steps more closely:

1. Define: Put simply, this step involves defining what the actual process problem is, and what its effect is on the rest of the process in question.
2. Measure: Once the problem is defined, current data should be measured. This will give you a baseline from which to start your improvements.
3. Analyze: Once the relevant data has been collected, an analysis should be conducted to help get to the root of the problem.
4. Improve: This is the trial-and-error part of the Six Sigma process, which means it could take the longest to complete. In this stage, solutions should be introduced, tested, recorded, and tweaked as needed.
5. Control: The right improvements may have been made, but the Six Sigma process doesn’t stop there. Any ongoing process should continue to be evaluated and improved upon over time. This requires full employee engagement as well as support from upper management.

What is lean manufacturing or “Lean Six Sigma”?

You may have noticed a common theme emerging when discussing lean manufacturing, Six Sigma, and maintenance in general: continuous improvement comes up time and again. Whether it’s total productive maintenance, lean manufacturing, or any other facet of maintenance and asset management, it’s important that maintenance teams pay attention to the data and continuously raise the bar for their chosen KPIs.

With that in mind, it makes sense that lean manufacturing and Six Sigma have converged in some instances. Organizations that use a Lean Six Sigma strategy understand it as a fact-based, data-driven philosophy of improvement. This definition acknowledges the fact that there are aspects to both strategies that are beneficial in a manufacturing setting and integrate well with a TPM strategy.

Harmonizing lean manufacturing and Six Sigma for performance

Lean manufacturing and Six Sigma share a commonality: a commitment to continuous improvement. Whether it’s streamlining maintenance workflows or enhancing production processes. This similarity has given rise to the concept of “Lean Six Sigma,” where the strengths of both methodologies merge together and create a powerful, data-driven strategy. As always, employing a total productive maintenance strategy will support each strategy by ensuring everyone is involved.