Lean manufacturing is a manufacturing system and philosophy that was originally developed by Toyota, Japan and is now used by many manufacturers throughout the world.
Lean Manufacturing can be defined as:
“A systematic approach to identifying and eliminating waste (non-value-added activities) through continuous improvement by flowing the product at the pull of the customer in pursuit of perfection.”
The term lean manufacturing is a more generic term and refers to the general principles and further developments of becoming lean. The term lean is very apt because in lean manufacturing the emphasis is on cutting out “FAT” or wastes in manufacturing process. Waste is defined as anything that does not add any value to the product. It could be defined as anything the customer is not willing to pay for.
Manufacturing philosophy is pivoted on designing a manufacturing system that perfectly blends together the fundamentals of minimizing costs and maximizing profit. These fundamentals are Man (labour), Materials and Machines (equipments) called the 3 M’s of manufacturing. A well-balanced 3M is resulted through lean manufacturing.
ELEMENTS OF LEAN MANUFACTURING
Those concepts that lead to the implementation of lean manufacturing successfully are called elements of lean manufacturing. The basic elements of lean manufacturing are waste elimination, continuous improvement, pull system, one-piece workflow, cellular manufacturing and 5S’s. When these elements are focused in the areas of cost, quality and delivery, this forms the basis for a lean production system.
1) Elimination of waste
Waste is anything that doesn’t add value to the product. Seeing whether the process is adding value to the product or not is the best way to identify wastes. Out of the complete processes in an industry only about 5 % actually add value to the product. Rest of the process does not add any value. Rest 35% activities are such that even though this doesn’t add any value but still it cannot be eliminated as it is necessary. For eg. Inventory cannot be completely reduced, scrap materials cannot be made zero, it may take few minutes to load unload and load for next operation etc.
2) Continuous improvement
Japanese looked at improving their work every time they do it. This lead to the development of concept called continuous improvement. Japanese rather than maintaining the improvement they have achieved they concentrated in continuously improving their work. This improvement can be in any field like quality, error proofing, lead-time reduction etc. So the focus should be on how you can improve your work than the same done last time.
In traditional mass production machines are arranged according to its functions. But in cellular manufacturing machines are arranged according to the processes involved in production. The plants layout is designed in such a way that transportation between machineries is reduced to minimum. For the implementation of such a good plant layout deep knowledge of processes as well as proper analysis of processes involved in production is necessary.
4) The 5 S’s
It is the Japanese method of keeping the work place clean and tidy. This helps in reducing many unnecessary movements.
The 5S’s are:
•Sort (Seiri) – Perform “Sort Through and Sort Out,” by placing a red tag on all unneeded items and moving them to a temporary holding area. Within a predetermined time the red tag items are disposed, sold, moved or given away.
•Set in Order (Seiton) – Identify the best location for remaining items, relocate out of place items, set inventory limits, and install temporary location indicators.
•Shine (Seiso) – Clean everything, inside and out.
•Standardize (Seiketsu) – Create the rules for maintaining and controlling the first 3S’s and use visual controls.
•Sustain (Shitsuke) – Ensure adherence to the 5S standards through communication, training, and self-discipline
Sachin is a B-TECH graduate in Mechanical Engineering from a reputed Engineering college. Currently, he is working in the sheet metal industry as a designer. Additionally, he has interested in Product Design, Animation, and Project design. He also likes to write articles related to the mechanical engineering field and tries to motivate other mechanical engineering students by his innovative project ideas, design, models and videos.