Benefits of One-piece Flow

At the heart of any Lean process is the pursuit of perfection through the continuous flow of work, one piece at a time.  This makes the 7 wastes and the problems hidden by inventory highly visible.  One-piece flow also does the following:

Builds in quality.   When doing one-piece flow, every worker is an inspector.  Each piece is looked at by the next process (the customer) very soon, so defects that are passed on are caught before too many more are made.

Reduces inventory cost.  Cash is freed up when inventory is reduced. The money to move, store, and manage is saved.  Also the less inventory you have, the less obsolescence you have.

Improves productivity.  Many non value-activities associated with batch production go away with one-piece flow.  Multi-process handling becomes possible when cycle times are balanced to takt time.

Frees up floor space.   One-piece flow gets rid of work in process and the space used for storage is opened up.  Flow requires processes to be connected and space between equipment to be reduced.

Simplifies material replenishment. One-piece flow paced at takt time allows material replenishment to be done by milk runs, timed deliveries or set quantity deliveries.  Continuous flow and line balancing make the material usage rate (line speed) more reliable and material delivery easier. 

Improves flexibility. One-piece flow reduces the time through the process. So you can wait longer to schedule the order and still deliver on time.  This lets you respond to last minute changes easier.

Improves scalability.  One-piece flow equipment can be designed smaller, slower (paced to takt time), and generally at lower costs.  Rather than making a process fast as technically possible, often resulting in local optimization and batch processing, very simple processes can be used.

Improves safety.   According to insurance studies the number one cause of workplace injuries in the is overexertion.  Lifting heavy containers is and moving large pallets of materials is reduced when lot sizes are one-piece. With fewer or no forklifts you also reduce forklift accidents, a major cause of injuries in factories (90 deaths and 90,000 accidents per year in the ).

Improves morale.   People can see the effect of the work they do when they perform more processes in one-piece flow.  People learn new skills when they are cross trained.  People work as a team when departmental barriers are removed.  People can see problems right away are given the authority to call for help or stop the line.  Problems are solved sooner and the culture shifts from one of finding blame to finding solutions.  This gives them a sense of fulfillment. 

Makes kaizen take root.   One-piece flow and kaizen go hand in hand.  If you do not solve problems and make process improvements, one-piece flow will not work.  You will be forced to go back to batching and hiding problems with inventory.

The road to one-piece flow is a challenging one, but the blueprint exists, and it is TPS and its many tools.  Contact us  to learn more.

"The more inventory a company has, the less likely they will have what they need.."

- Taiichi Ohno, Founder of the Toyota Production System