Lean Glossary


Andon Board—A visual display device that gives current production information, schedule changes, and identification of potential problems.

Andon Lights—Colored lights, usually stacked, to indicate the current status of a cell, production line, or individual piece of equipment. The lights can identify: no problems, need for help or materials and/or stoppage or shutdown.

Balancing (line balancing)—Building the cycle time concept into the standardized operations of a production line for maximum efficiency. Leveling the cycle time for all operations within a line or process.

Batch & Queue—The common practice of building large batches and holding them in queue before beginning the next operation. Opposite of Single Piece Flow.

Cells—The layout of different machines and/or operators in a tight format within a designated area. Cells are usually U, I, L, or T-shaped and take advantage of Single Piece Flow with a minimum number of operators.

Changeovers—The removal, exchange, and installation of a new type tool, die, or mold to produce a different product than was produced in the last run. Changeover time runs from last good piece of Product A until the first good piece of Product B.

Cycle Time—The time required to complete one cycle of an operation. Usually measured from start to start or stop to stop.

Error Proofing—See Mistake Proofing

Five S (5S)—Five terms that refer to workplace organization that come from Japanese words seri (sort), seiton (set in place), seisi (shine), seiketsu (standardization), and shitsuke (sustain).

Five Whys—Asking “why” five times when looking for the root cause of problems to develop effective corrective and preventive actions.

Flow—The sequential accomplishment of activities along the path of a production line without interruption.

Frontal Loading—Replenishment and removal of materials for a production or service line in front of the operators. Prevents operators from having to turn around to receive or move parts.

Just-in-Time (JIT)—Producing and delivering the right materials, to the right place, in the right quantities, just as they are needed. JIT systems eliminate waiting time and buildup of materials between activities.

Kaizen—Continuous, incremental improvement of an operation/task that adds value each time it is repeated.

Kanban—A card or placard attached to containers of materials that control the pull of materials into and out of production lines. This could be markings on floors, shelves, or tables for the same purpose.

Mistake Proofing—The activity of designating processes so they can not be done wrong or cannot pass a defective item to the next process in line. Sometimes called Error Proofing or Poka-Yoke.

Overall Equipment Effectiveness (OEE)—A measure of availability (time), performance (rate), and quality (output) for an individual piece of machinery or production line.

Poka-Yoke—See Mistake Proofing

Process—A series of individual activities to produce a product or service.

Process Yield—The rate at which a product or service is produced. It is usually measured in units per time.

Pull—A system of only producing when there is a need or “pull” from the operation before yours, all the way to the customer. The opposite of push.

Push—A system of building products and “pushing” them to the next operation, even though there is no immediate need for the product. Results in excessive inventory kept just-in-case. The opposite of Pull.

Sequencing—Repeating a pattern of producing different products to accommodate production capability and varying customer demands.

Single Minute Exchange of Dies (SMED)—The exchange of dies, tooling, and/or molds within a time limit of 9 minutes or less.

Single Piece Flow—A system where products/materials proceed, one at a time through a series of operations from order taking to final shipment. Opposite of batch & queue.

Single Transaction Flow—Similar to Single Piece Flow, where one transaction is completed before another is started.

Smoothing—A production system to eliminate peaks and valleys in the work load and avoids excessive production. Tied closely to sequencing and line balancing.

Statistical Process Control (SPC)—Using statistical tools to assist in controlling the quality of an operation.

Standard Operating Procedures (SOPs)—Documents that include the steps within a process to be followed. Usually includes words, pictures, and/or graphics to aid in the understanding of the procedure.

Takt Time—The rate at which a customer pulls product from the production line daily. It is figured by dividing the daily operating time in seconds by the customer requirements per day in units.

Transactional Processes—Those processes where a transfer of materials, knowledge, information, or services are exchanged between two individuals or between an individual and a piece of equipment. Typically most non-manufacturing processes fall into this category.

Value—Defined by the customer as being the correct quality, quantity, price, and delivery time as expected.

Value Stream Mapping—Identification of all the specific activities occurring during the value stream. These activities include: time, distance, materials movement, inspections, and value-added production.

Visual Control—The placement in plain view of all tools, parts, materials, production activities, and indicators so the status of the system can be understood by everyone at a glance. A critical part of a 5S system.

Visual Factory—A factory or facility with visual controls throughout, to indicate the current status and past results of all manufacturing and/or transactional processes that occur in all departments.

Work-in-Progress (WIP)—Those portions of production that have not been completed, but have had machine or manual work invested in them as they move through the value stream.

Zoning—The segregation of a work area with clearly marked boundaries. Containers, materials, and equipment within the zone are usually marked with specific zone identification.