Lean Manufacturing is a managment philosophy that focuses on the reduction of eight specific wastes - Overproduction - push vs. pull manfacturing; producing parts before they are needed anywhere throughout a process
Transportation - The need to move parts from one part of the facility to another between operations.
Motion - Time spentwalking, searching, reaching and any type of excessive handling.
Waiting - unbalanced operations that create bottlenecks; waiting in between machine cycles, for materials, machine downtime and machine change over time.
NVA Processing - Over engineering, non-value added processes and processes needing to be combined.
Inventory - Excessive raw material shortage, WIP and finished goods inventory.
Defects - scrap created durring manufacturing or customer returned products.
Under - utilized Talent and Ideas - not involving the people in the process and there ideas for improvemnt.
Traditional manufacturing is typically less than 20% efficient because of the lack of "value-added" activities surrounding the "value-added". The goal is to design and build advanced manufacturing solutions that maximize value while eliminating "non-value-added" activities.
Why Does Lean produce such great results?
Example:
Process #1 takes 30 minutes
Process #2 takes 20 minutes
Process #3 takes 10 minutes
You plan to make 100 parts to stock starting in 3 days
Your typical delivery is 3weeks even though materials are in stock.
You are running two shifts.
Many other parts are scheduled in front of this project at all 3 processes all going into finished goods inventory or will become WIP.
Your Customer calls and needs 5pcs RUSH!!... Good Luck.
Traditional Manufacturing (batch and queue)
Process #1 3days wait time + 30minutes x 100pcs = 7 work days
Process #2 2days wait time + 20minutes x 100pcs = 4 work days
Process #3 1days wait time + 10minutes x 100pcs = 2 work days
Inspection 2days wait time +1minute x 100pcs = 2 work days
Total = 15 work days x 2 shits = 30shifts With Lean Manufacturing (Single Piece Flow)
The Customers order signals manufacturing to start producing 5 units.
The Kanban system is filled with one part in between each process of the value stream.
Combine operation #2 and #3 to balance the work load at 30 minutes per operation.
Thirty minutes later the first piece is ready to ship - no waiting - no need for inspection because quality is build into the process. Thirty minutes later the second piece is ready to ship
After two and a half hours the shipment of 5 pieces is on it's way to the customer. Almost seems unreal and obviously there is alot of planning , training and work to get to this type of a system, but with a proven company it's real and very possible.