Lean manufacturing

What is lean manufacturing?

Lean manufacturing, also known as lean production or just lean, is a manufacturing system based on continuous improvement. Lean manufacturing aims at minimizing waste, and its premise is a philosophy, set of tools and techniques, way of thinking, and way of life.

To be successful at lean manufacturing, you need to understand what it takes to make your business more efficient while reducing costs and improving quality.

What are the advantages and disadvantages of lean manufacturing?

Lean manufacturing is known for its many benefits in manufacturing and maintenance, but it also has some drawbacks. Below are the advantages and disadvantages of lean manufacturing:

Advantages

• Reduced waste: The primary goal of lean manufacturing is to eliminate waste. This includes waste of time, materials, and human resources, resulting in improved efficiency and effectiveness.
• Increased productivity: By eliminating wasteful practices and focusing on the essentials, lean manufacturing can drastically increase productivity.
• Improved customer satisfaction: Lean manufacturing often results in faster production and higher-quality goods, which can significantly improve customer satisfaction.
• Cost savings: By reducing waste and increasing efficiency, lean manufacturing can lead to significant cost savings in the long run.
• Employee engagement: Lean manufacturing involves everyone in the organization, creating an environment of continuous improvement and learning, which can boost employee morale and engagement.

Disadvantages

• Implementation challenges: Lean manufacturing requires a significant organizational culture change and can be difficult to implement. It requires total commitment from all levels of the organization, and with this, it can be easier to achieve the desired benefits.
• Dependency on suppliers: Lean manufacturing relies heavily on just-in-time (JIT) production, leaving a company vulnerable to supply chain disruptions.
• Employee burnout: Since lean manufacturing is heavily focused on efficiency, it may increase pressure on employees, potentially leading to stress and burnout.
• Less flexibility: The focus on reducing waste and increasing efficiency may result in less flexibility to handle unexpected changes or customize products according to unique customer needs.
• Potential for quality issues: The drive for efficiency and reduced costs may sometimes compromise the quality of products if not appropriately managed.

What are the lean principles?

The lean manufacturing principles were established due to the Toyota production system (TPS). They include five core principles, although some teams argue that additional principles exist. The general lean principles are:

1. Identify value: You begin by understanding your customer's values in your product or service. This forms the basis of all lean activities. If a feature or process doesn't add value as perceived by your customer, it's wasteful.
2. Map the value stream: Once some value has been identified, the next step is to map out the entire process or flow that leads to that value being delivered to the customer. This includes every step, from raw material to the finished product, in the hands of the consumer. During this mapping, activities are often categorized into three types: those that add value (VA), those that don't add value but are necessary under current conditions (NVA), and those that don't add value and are unnecessary (waste).
3. Create flow: After mapping the value stream and identifying waste, the goal is to ensure the processes run smoothly without interruptions, delays, or bottlenecks. This can be achieved by reorganizing workstations, cross-training employees, and introducing more efficient tools and techniques.
4. Establish pull: In a lean system, production is driven by actual demand (pull) rather than forecasts (push). The idea is to produce only what is needed when it's needed. Techniques such as Kanban can help set up a pull-based system, ensuring that resources are only consumed when there is customer demand for the final product.
5. Continuous improvement: The last principle is the method of continuous improvement, sometimes called Kaizen. This is where teams constantly look for ways to refine and optimize processes. With this final step in place, organizations can adapt more quickly to changes and always deliver maximum value.

What are some common lean manufacturing techniques or methods?

There are various methods for lean manufacturing, but the most commonly used by manufacturers and maintenance teams include:

• 5S: This is a systematic approach to workplace organization and standardization. The five S's stand for:
  • Sort (Seiri): Remove unnecessary items from the workplace.
  • Set in order (Seiton): Organize the remaining items.
  • Shine (Seiso): Clean the workplace regularly.
  • Standardize (Seiketsu): Establish standardized procedures.
  • Sustain (Shitsuke): Maintain and review standards.
• Kanban: A visual tool that controls the production flow by signaling when the next item should be produced or when more materials should be procured. Kanban cards represent parts or products and help ensure a pull-based production system.
• Value stream mapping (VSM): A visual representation of the flow of materials and information through the production process, helping to identify areas of waste and inefficiency.
• Total productive maintenance (TPM): A method that emphasizes the importance of maintaining and improving the integrity of production and quality systems, ensuring that machinery and equipment are always available and operational.
• Jidoka (autonomation): Automation with a human touch. It focuses on designing machines that detect and stop abnormalities automatically, thus preventing the production of defective products.