Lean is a complete system that can be used across business departments such as manufacturing, production, marketing, distribution, and others field. Lean was a term to describe the revolutionary production and management system. This system accomplishes more work with fewer resources by eliminating waste in manufacturing operations. For some people, Lean and Just in Time are often mixed up. One of their differences is the JIT system focus on efficiency, while the lean focuses on using efficiency to add value for the customer. Other than that, JIT is a part of the lean method that eliminates the waste of excessive inventory. Lean manufacturing takes the concept of JIT and reexamines in light of customer value. More detail information about Lean will be discussed in the following paragraph.
Another definition of lean is a systematic approach to identifying and eliminating waste through continuous improvement in pursuit of perfection. The first principle of lean manufacturing is that every step in the production process muss add value that customer wants. The goals of this system are producing more products using current resources and lower the stock in inventory. Also, it gets all the needed parts to be assembled at the right time. Then, the forecast in this system measures how long it takes to make the product and deliver on time to the customer. By using lean manufacturing, a company can have a lower production cost but higher profits and wages. Besides that, it supports ISO 14001 about environmental management and green manufacturing.
To achieve lean manufacturing goals, there is some formula that must be applied. The first is teamwork. Second, observe or analyze the current situation. Third, ideas, the team develops ideas on how to eliminate waste. Fourth, communication, make sure everyone knows the goals, the changes being made, the successes, and the failure. Fifth, culture, create a continuous improvement culture and always consider new ideas. There are also some tools in lean manufacturing. Those are 5S, sort, set in order, shine, set rules, sustain. Then, there are standardized work practices, visual controls, plant layout, batch reduction, point of user storage, quality at the source, quick changeover, etc.
In the manufacturing field, there is also a term called “Theory of Constraints”. The constraint will determine the output of a system whether they are acknowledged and managed or not. There are six steps that stated clearly in the theory of constraint. The first theory of constraint state, “identifies the appropriate measures of value”. Second, Identify the bottleneck. Third, Use bottlenecks properly. Fourth, Synchronize all other processes to the bottlenecks. Fifth, increase the bottleneck’s capacity. Last, avoid inertia and return to steps number one.
From the explanation above, it can be seen that Lean and JIT are not exactly the same. In addition, the JIT system there only seven waste, which are overproduction, waiting, transportation, inappropriate processing, excessive inventory, unnecessary motion, and defects. While in lean manufacturing there is eight waste. Those are defects, excess motion, waiting, processing, overproduction, transportation, inventory, and underutilized people or waiting for more work to do. One of the ways of finding waste in lean manufacturing is by using a value stream map. This map helps to analyze, design, and manage the flow of materials and information required to bring a product to a customer. In conclusion, lean manufacturing and Just in Time are different even in terms of its waste.
Fani Fafas Tafia 