By Jim Johnson
One of the often overlooked and underutilized tools in the Lean Manufacturing toolbox is plant layout or facility design. This initiative isn’t typically considered until a company goes through an expansion, relocation or major rearrangement, prompted by circumstances such as equipment purchase, new product line offering or the urgent need to increase efficiency.
Most companies start out with a nice and efficient layout, but over time either expand, add or delete products, add equipment, add storage capabilities or accumulate items that need to be placed somewhere within the facility. Through this process, employees get used to the arrangement and make concessions to the now inefficient layout.
In good Lean practice, we always want to reduce or eliminate waste. Inefficient layout leads to increased material handling, and the waste of time in transporting materials, which then leads to further waste in overproduction, waiting, excessive inventory and large batch sizes. The thinking is: “I don’t want to move less than a pallet load to the next process. I want to decrease my material handling.”
With these changes, though, comes the consequence of waste.
To alleviate this, companies—even those without plans for expansion or relocation—should consider rearranging their workspace layout.
To plan for a rearrangement, expansion or relocation, we investigate a company’s current situation using the P, Q, R, S, T approach:
P—What are the Product lines (now and expected)?
Q—What is the anticipated Quantity for each of these products?
R—What are the Routing steps that these products take?
S—What are the Storage requirements and methods for these products (including raw material, work in process and finished goods)?
T—How are the materials Transported between operations, and what is the frequency of handling?
In addition, it is important to look at the activity of the relationships, between operations and/or departments to determine which areas need to be near each other and which do not, or should not (e.g. for safety or environmental reasons).
Given all this information, we can then work with the company to provide various solutions that eliminate the wastes and increase efficiency and throughput. We then weigh the pros and cons of each potential solution to ultimately reach the best plan for the future.
When incorporating a new plant layout, companies should also take advantage of the opportunity to utilize other lean tools, such as 5S, visual management, batch size reduction, point-of-use storage, limited inventory (Kanban) and cellular flow. These can help to further enhance the improved efficiency, and reduce or eliminate pesky wastes.
Keep in mind that this approach to proper layout is not only used on the shop floor. It can be adapted to any system that involves providing a product or service to an end user, such as an office environment, distribution center, hospital or retail center.
