Lean vocabulary: the dictionary for your organization's performance

Ensures that a production process stops whenever a problem or defect occurs. On an automated line, this usually means installing sensors and buttons that automatically stop the line when an abnormality is detected.

See: Error-Proofing, Fixed-Position Stop System, Jidoka.

Production facilities usually managed according to the philosophy of mass production.

Compare with : Greenfield.

A location where the processing steps for a given item take place immediately one after another, so that parts, documents, etc. can move in a flow very close to continuous, whether one unit at a time or in small batches, maintained throughout the complete processing sequence.

See: Continuous Flow, Operator Balance Chart, Standardized Work.

A method of conducting one-piece flow in a cell in which the machines unload parts automatically, so that the operator (or operators) can carry a part directly from one machine to the next without stopping to unload it, thereby saving time and motion.

See : Cell, Continuous Flow.

The process of switching production from one product to another on a machine (for example, a press or an injection molding machine) or on a series of linked machines (an assembly line or cell) by changing parts, dies, fixtures, molds, etc. (Also known as setup.) Changeover time is measured as the time elapsed between the last part of the run just completed and the first good part after the changeover.

See : Single-Minute Exchange of Die - SMED.

Producing and moving one item at a time (or a small batch of items) through a series of processing steps as continuously as possible, with each step making just what is requested by the next step.

See : One-Piece Flow, Batch and Queue, Flow Production.

Meeting customer requirements exactly with the minimum amount of resources.

See : Overproduction, Seven Wastes.

Methods that help operators avoid mistakes in their work, such as choosing the wrong part, assembling a part incorrectly, forgetting a component, etc. Also known as poka-yoke (defect-proofing) or baka-yoke (foolproofing).

See : Inspection, Jidoka.

A method of dealing with problems on production lines by stopping the line at the end of the work cycle, that is, at a set position, if a problem is detected and cannot be solved within the work cycle.

See: Andon, Automatic Line Stop, Jidoka.

Providing machines and operators with the ability to detect when an abnormal condition has occurred and immediately stop work. This enables operations to build quality into the product at each step of the process and separates people from machines for more efficient work. Jidoka is one of the two pillars of the Toyota Production System, along with Just-in-Time.

See : Andon, Error-Proofing, Automatic Line Stop, Inspection, Just-in-Time (JIT), Multi-Process Handling, Toyota Production System, Visual Management.

Three terms often used together in the Toyota Production System (known as "the three Ms") that collectively describe wasteful practices to be eliminated.

See: Heijunka.

A work practice in which operators run more than one machine in a layout of process islands. It requires separating human work from machine work and is normally made easier by applying jidoka and auto-eject devices on the machines.

See: Jidoka, Multi-Process Handling.

A work practice in which operators work on more than one process in a layout oriented to the flow of products. It requires training operators to handle different types of machines (e.g., cutter, polisher, tester, etc.) so that they can move products through the cellularized operations.

See: Multi-Machine Handling.

Tasks in processes with many operators that require him or her to interrupt the work rhythm or leave the area.

See : Standardized Work.

Work performed on an item by a machine or a person.

See: Process.

Operational availability is the fraction of time a machine works properly when needed. Operating rate is the amount of time in a given period (shift, day, etc.) that a machine is used.

See : Overall Equipment Effectiveness (OEE).

A graphical tool that helps create continuous flow in a multi-step, multi-operator process by distributing the operator's work elements in relation to takt time. Also known as an operator loading diagram or yamazumi board.

See: Yamazumi Board.

A total productive maintenance (TPM) metric that measures how effectively a piece of equipment is used.

See : Total Productive Maintenance (TPM).

Grouping of activities by type, rather than in the sequence needed to design or make a product.

See: Mass Production, Material Flow.

A disciplined method for designing a lean production process for a new product, or for fundamentally redesigning the production process for an existing product when the product or demand changes substantially. It may also be called Lean Process Development.

See: Kaizen, Kaizen Workshop.

Tagging unnecessary items in order to remove them from a production area during a 5S exercise.

See : 5S.

Highly capable process equipment that is easy to maintain (and therefore available to produce whenever needed), allows quick changeovers, is easy to move and is designed to be installed in small increments of capacity, in order to facilitate labor and capital linearity.

See : Capital Linearity and Labor Linearity.
Compare with : Monuments.

The process of reducing the time needed to change a process over from one model to another, from the last piece of the previous product to the first good piece of the next product.

See: Changeover, Single-Minute Exchange of Die (SMED).

Taiichi Ohno's categorization of the seven major wastes commonly found in mass production: overproduction, waiting, transportation, processing, inventory, motion and correction.

See: Changeover, Setup Reduction.

An engineer and consultant whose books and teachings were key contributions to the dissemination of the Toyota Production System.

See: Setup Reduction, Single-Minute Exchange of Die - SMED.

A process for changing production equipment over from one part to another in the shortest possible time. SMED refers to the goal of reducing changeover times to a single digit, or less than 10 minutes.

See : Changeovers, Setup Reduction, Shingo.

Available production time divided by customer demand. For example, if a factory operates 480 minutes per day and customer demand is 240 units per day, takt time is two minutes. Similarly, if customers want two new products per month, takt time is two weeks. The purpose of takt time is to precisely match production with demand by providing a rhythm for the production system. It is the heartbeat of a lean system.

See: Cycle Time, Heijunka, Just-in-Time Production, Operator Balance Chart, Pacemaker Process, Pitch, Takt Image.

A production system developed by Toyota Motor Corporation to provide the best quality, the lowest cost and the shortest lead time through the elimination of waste. TPS is built on two pillars, Just-in-Time and Jidoka, and is usually illustrated by the "house" shown below. TPS is maintained and improved through iterations of standardized work and kaizen, following PDCA, or the scientific method.

See : Jidoka; Just-in-Time Production; Lean Production; Ohno, Taiichi.

Any activity that consumes resources but creates no value for the customer. Most activities are waste (muda). There are two types of waste: type 1 and type 2. Type 1 muda creates no value but is unavoidable in a given situation. An example would be inspecting welds to ensure quality.

See : Muda, Seven Wastes.

Yamazumi is the Japanese term for "pile" or "heap".

See : Operator Balance Chart.