Lean Manufacturing and Six Sigma Definitions

Glossary terms, history, people and definitions about Lean and Six Sigma

Single-Stall Production System

Single-Stall Production System (or individual production) is a method of work that takes conveyer-belt or assembly line processes to the next level. One highly skilled worker is trained to perform all steps of the process by themselves (often in one stall to reduce floor space), instead of handing off the work to multiple workers in an assembly line. It can take months or years to develop their skills so they can perform each step at high quality, but it can be the most efficient way to complete a process from beginning to completion.

In a traditional assembly line, workers are studied and each job is balanced to match the other steps. The variation in worker to worker can lead to slight inefficiencies, and there is less motivation to improve your process time, as it will result in an unbalanced line and excess inventory or raise concerns with their supervisor (wondering why they finished so early). When product or services change, a rebalancing of the assembly line is required, which can take significant time to adjust. Single-stall product or service changes can be incorporated in hours or days.

In a single-stall system, if the worker makes improvements to their work, it allows them to start the next step earlier, and ultimately bring down the total completion time. There is also a stronger sense of pride in the work, since they completed the entire order themselves. In an assembly line, no one person has total ownership of the final product or service.

Assembly lines also require many workers and lots of work-in-process (WIP), and if there is absenteeism, the line will be slowed down or unable to be run. A single-stall only requires one worker, and is not impacted by absenteeism from others on the team. It is also easier to adjust the number of active stalls each day to the actual customer demand. When a problem arises, the worker can resolve it much more quickly than when a problem arises on an assembly line.

The first video is from Canon in Torida, Japan that explains the concept and the benefits of the single-stall. The workers in a single-stall system are called “meisters” (master craftsman: multi-skilled worker with a broad range of skills and knowledge across multiple processes) and are paid more than assembly line workers.

The entire video from the NHK Documentary (including Canon) also features Sanyo and their transition to multi-tasking (single-stall). After some difficulty, they also experienced success. They use the term multi-tasking, but it doesn’t seem like the correct term, single-stall seems more appropriate. The video about Sanyo starts at 24:34.

The next video is from Toyota Murai and the Motomachi Plant in Japan. They take a slight variation from Canon’s approach, using multiple workers on one vehicle, but all in one space focused on one vehicle.

Below is another video showing a larger stall due to the equipment (less assembly), but the employee performs all the steps like in a single-stall.

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