Lean manufacturing and Six Sigma are two popular, customer-centric methods of organizing and running businesses, often, but not exclusively, in manufacturing. While they have similar ultimate goals of reducing waste, improving quality or value, and maximizing profits, they are not the same.
Here, we’ll look at the main concepts and practices of both, as well as how they differ.
Key Lean Manufacturing Concepts
At its core, lean manufacturing is about identifying and eliminating waste and striving for “continuous improvement” and “pull” or just-in-time production flow.
Waste is defined as anything that doesn’t add value in the eyes of a paying customer. It is interpreted broadly to include things that amount to extra costs for customers but provide little or no added value for them. These include:
- Excess transportation
- Excess inventory
- Unnecessary movement of people, products, or equipment
- Waiting
- Overproduction
- Over-engineering and unnecessary product features
- Product defects
Some also identify another form of waste: untapped in-house talent.
In practice, personnel look for waste in all aspects of operations in an effort to root it out. This improves efficiency and quality and reduces operational costs, all of which make customers happier. Lean principles are incorporated through these practices:
- Continuous flow of production at appropriate volumes
- Just-in-time delivery instead of overstocking
- Workspace tidiness and organization
- Visual aids and signals to guard against human error
- Identifying problems and their root causes
- Close attention to cycle times
2-Second Lean
This streamlined version of lean manufacturing encourages a daily morning meeting with staff, and finding and fixing waste in day-to-day operations. Personnel are empowered to make the changes that stop wasteful operational friction. Examples include:
- Visual assessment of desks and workstations for clutter, stray items, or disorganization
- Quick fixes, including straightening papers and tools, keeping surfaces clean, and rearranging work spaces for better flow
- Process improvements such as combining steps and removing redundancies, reducing paperwork, direct communications, and removing bottlenecks
- Team collaboration such as sharing quick-fix ideas, brainstorming on pain points, and celebrating positive outcomes
Key Six Sigma Concepts
Six Sigma defines waste as the result of variation in processes, which leads to reduced quality in management, production, or products. Statistical analysis is used to assess how much a process varies in practice from the mean or target value. The core idea is that by minimizing variation, quality improves.
Implementing quality assurance measures ensures Six Sigma principles are applied effectively.
Six Sigma has these key principles:
- Customer Focus. Establish quality standards by understanding customer needs and sales loyalty factors.
- Assess the Value Stream. Map process steps and gather measurable data to identify problem areas and root causes.
- Resolve Points of Variation. Remove any part of the process that contributes to inconsistency and reduced quality.
- Expand Efforts. Involving stakeholders in analysis and problem-solving, as well as Six Sigma certification, helps ensure long-term success.
- Ensure a Flexible and Responsive Ecosystem. Design changes for quick and seamless integration for the greatest success.
There are five steps to finding and fixing problems:
- Define the problem process, desired outcome, and customers affected.
- Measure by collecting data to establish a baseline for the process.
- Analyze the gathered data to find anomalies or points of variation.
- Improve the process with a plan, then testing it.
- Control and stabilize the outcome with safeguards and procedures.
Major Differences between Lean and Six Sigma
| Feature | Lean | Six Sigma |
|---|---|---|
| Focus | Eliminate waste | Reduce defects and variability |
| Methodology | Focuses on process flow and value streams | Focuses on statistical analysis and data-driven decisions |
| Tools | Value stream mapping, 5S, Kaizen, JIT | DMAIC, SPC, DOE |
| Goal | Efficiency and speed | Quality and consistency |
Both approaches focus on reducing waste to improve quality, especially from the viewpoint of the customer. They have different definitions of waste and different approaches to eliminating it, however. Lean defines waste as anything that doesn’t add value to a process, whereas Six Sigma defines waste as what results from variation and inconsistency within operations.
Lean improves the design and management of operational processes to minimize inefficiencies attributed to delays, errors, and waste. These concepts are often applied to every aspect of a business, not only the manufacturing portions.
Six Sigma relies on measurement and data analysis to pinpoint inconsistencies in manufacturing processes. Once the root cause is identified, a process can be adjusted and tested to verify its efficacy.
For industries requiring precision, custom material handling solutions can be designed with lean and Six Sigma principles in mind.
Six Sigma and Lean Six Sigma
Lean Six Sigma (LSS) combines elements of both approaches to increase value for customers. In this approach, reducing waste and boosting efficiency with lean principles is further quantified with objective data. This helps verify that the perceived problem is actually at the root of the issue, and it makes tracking change easier and quantifiable.
Industries like nuclear energy rely on Lean Six Sigma for precision and efficiency in material handling. Single-failure proof cranes are an excellent choice for the nuclear industry.
More Manufacturing Insights from American Crane
At American Crane & Equipment Corp. we understand the value of efficiency and consistency in manufacturing. We are a leading manufacturer of overhead crane systems, hoists, and material handling equipment for industrial processes with little room for error or waste.
Explore our resources, including ebooks and brochures, to learn more about our products and services, or contact us to discuss your application.