In the manufacturing industry, waste refers to any action or step that does not add value to the customer. These are all of the little extras within a process that the customer does not want to pay for. The goal of lean manufacturing is to remove waste from the manufacturing process.
Taiichi Ohno, father of the Toyota Production System (TPS) identified the original seven wastes of manufacturing. An eighth waste was added in the 1990s when TPS was adopted by the western world. The 8 wastes of lean manufacturing include:
- Transportation
- Inventory
- Motion
- Waiting
- Over-production
- Over-processing
- Defects
- Skills
It’s important that manufacturers learn all they can about wastes in the manufacturing process.
Transportation
Waste in transportation occurs when people, tools, inventory, equipment, or products must be moved further than reasonably necessary. Manufacturers can eliminate transportation waste by ensuring workers have everything they need to complete each project close at hand. This includes, but is not limited to, all necessary people, equipment, tools, and materials.
Inventory
Excessive inventory can cause problems for manufacturers. Having too much inventory can lead to damaged materials, greater lead times, and inefficient allocation of capital. Problems such as over-purchasing and over-production often result in extra inventory. In order to combat waste, manufacturers should purchase raw materials only when they need them, reduce buffers between production steps, and create a queue system to prevent over-production.
Motion
Waste in motion includes any extra movement required to complete a task. This includes having to walk to fetch tools or materials and spending excessive amounts of time searching through inventory. Keeping work spaces organized, materials close at hand, and reducing inventory can help eliminate waste caused by motion.
Waiting
Waste occurs when staff must wait for materials or equipment, email responses, and computer programs to load. Using standardized work instructions and utilizing multi-skilled workers who are better equipped to adjust to changing demands is the best way to eliminate waste caused by waiting.
Over-Production
Producing more products than required can create a lot of waste. Manufacturers should take care to only produce as many products as required.
Over-Processing
Over-processing occurs when staff performs more steps or adds more components than required to complete the project. Before starting any project, its important staff fully understands what the customer wants. This sets the standard for what needs to be done.
Defects
An obvious cause of waste, defects require scrapping and reworking of products. The best way to prevent waste caused by defects is to fully test all components throughout production.
Skills
Although not part of the original seven wastes, most manufacturers recognize the waste caused by not utilizing employee skills and talents. Manufacturers can prevent waste by allowing staff members to provide input and throughout the manufacturing process.