Lean manufacturing, or simply “lean,” is a systematic method designed to minimize waste in a manufacturing system while productivity remains constant. Originating in Japan in the Toyota Production System (TPS), lean manufacturing strives to minimize waste within a manufacturing operation, with the idea being to clearly portray what adds value by removing what doesn’t. As your company begins to think about lean manufacturing it’s important to keep in mind the process of going lean takes time – like turning a cruise ship around.
There are several different lean techniques, allowing each organization to fit lean manufacturing techniques into its own distinct production process. We’re going to discuss the eight types of waste lean manufacturing seeks to eliminate and the principles, tools, and techniques manufacturers around the world have implemented into their manufacturing processes.
Lean Manufacturing: 8 Types of Waste
As we mentioned earlier, going lean starts with eliminating waste to focus on what adds value to your process, which leads to adding value for your customers. It’s important to know the types of waste and how they affect your business. There are eight types of waste:
1. Defects
Probably the most visible type of waste, defects are scrap products or products that don’t meet commercial specifications. They can lead to many types of waste, most notably the one we will discuss later – waiting. Defects cause delivery delays and logistics headaches which most likely lead to a decline in customer satisfaction. It’s also going to cost money to rework defective products. Fixing defects causes your company to spend extra time fixing issues and filing paperwork.
2. Overproduction
Companies love to produce in bulk. While it seems like a good idea initially, customer needs change fairly constantly and the market fluctuates and forces change even more frequently. Overproduction causes excess inventory which leads to storage expenses like paying for space and paying people and equipment to move the product around.
3. Waiting
Waiting is a byproduct of many types of waste and it wreaks havoc on customer satisfaction. A good way to look at waiting is, a product or your customer might be ready for the next step (packaging or shipping for example), but the next step in your process isn’t ready to perform the task. In healthcare, this might look like a full waiting room. In manufacturing, this might look like machine downtime causing packaging delays. Addressing maintenance tasks such as regreasing practices can go a long way in reducing unplanned downtime.
4. Non-Utilized Talent
Often overlooked as a form of waste, not using your employees to their full potential, talents or skills can have a big effect on your company’s bottom line. Poor teamwork, minimal training, bad communication, and unnecessary administrative tasks are common examples of non-utilized talent waste.
5. Transportation
Transportation is the movement of goods from one location to another. In manufacturing, this might mean performing different tasks in different locations. For example, producing product parts in China and shipping them to America to assemble. This process doesn’t add value to the end product, it doesn’t change the end result and it adds more cost. If you look at Toyota’s manufacturing setup, many of its suppliers are near the production plants.
6. Inventory
Similar to overproduction, inventory waste happens when your product is sitting there waiting to be sold. The difference between overproduction and inventory waste is that inventory has a physical cost associated with it, whereas overproduction is assumed. Overproduction often causes inventory waste by making more than your customers want or assuming demand will be there down the road.
7. Motion
The unnecessary movement of people, machines, or items that don’t add value is a waste of motion. In other words, wasting time. This form of waste is usually caused by not following the 5s’ lean manufacturing principle. Common examples include employees looking for materials or equipment in poorly designed workspaces. One way motion can be reduced is through production or maintenance automation.
8. Extra Processing
Extra processing, or over-processing, refers to adding work that isn’t required. Extra processing costs hit you in the form of the time of your staff, materials used, and equipment wear, and they add up over time. It also makes your process less efficient because employees performing the extra processing tasks could be doing value-adding tasks instead.
The 5s System for Lean Manufacturing
The 5S system is an organizational method stemming from five Japanese words: seiri, seiton, seiso, seiketsu, and shitsuke. These words translate to organize, tidiness, clean, standardize and sustain. They represent a five-step process meant to reduce waste and increase productivity and efficiency.
- Seiri (organize): The first step, Seiri, involves eliminating clutter and unnecessary items from the workspace.
- Seiton (tidiness or orderliness): Next, workers must set an order by ensuring there is a place for everything, and everything is in its place.
- Seiso (clean): This step involves cleaning the workspace and always keeping it in a clean state.
- Seiketsu (standardize): Standardizing all work processes and keeping them consistent, so any worker can step in and perform a job if necessary is vital.
- Shitsuke (sustain): Finally, we want to constantly maintain and reinforce the previous four steps.
Bottom Line
When it comes down to it, almost every company has room for improvement when it comes to minimizing waste, making high-quality products, and lowering their overall production cost. If you decide to go lean, remember it takes time to implement the correct methods, tools, and philosophies we’ve discussed. Once your team learns these techniques, they’ll be able to reduce one or more of the eight types of waste just by doing their job.