Cell Design and Pull Systems 161

cells

An arrangement of machines, tooling, materials, and operators structured around the design of similar products. Cells encourage smooth product flows and use space efficiently.

cellular manufacturing

A lean manufacturing method that uses specialized groupings of machines, people, and materials.

changeover time

The non-value added time required to convert a setup for one product line to a setup for another product line. Changeover may require switching fixtures, tools, programming, and other aspects of the manufacturing process.

changeovers

The time it takes to tear down the setup for the current product type, prepare for the next product type, and successfully produce the first good part.

cycle time

The time it takes to perform a task and move to the next step. One of the major goals of lean manufacturing is to match cycle time to takt time.

ekanban

An electronic kanban method used to signal production and material movement. Common ekanban methods include email or scanned barcodes.

error detection

The inspection of a part during and after production to determine if errors have occurred. Error detection does not try to prevent errors.

error prevention

A continuous improvement method that studies why and how errors occur. Error prevention creates ways to stop these problems from happening again.

external customers

An outside organization or individual that receives a product or service from the company.

flow shop

A manufacturing facility that produces one or two similar products using high-volume specialized equipment. An assembly line is an example of a flow shop.

in-process inspection

The inspection of a part during production to detect errors. Errors that are detected early may allow the part to be reworked or may prevented from continuing through the manufacturing process.

internal customers

A department or individual within the company that relies on others to satisfy the external customer. For any cell, the next cell in a process is always the internal customer.

inventory

Temporary or long-term storage of parts or products that are either finished or in progress. With pull systems, inventory is reduced or eliminated.

job shop

A manufacturing facility that produces several different products in smaller batches. A machine shop is a type of job shop.

just-in-time

JIT. A lean approach to production in which materials and products are ready precisely when needed, thus reducing or eliminating inventory and in-process parts.

kaizen

A Japanese word that means "change for the better." Kaizen is a combination of maintenance, problem solving, and innovation that is generally performed by a team.

kanban

A Japanese word meaning "card signal." In pull systems, it represents any visual method used to show the need for parts or products to be moved or produced.

lean

An approach to manufacturing that seeks to reduce the cycle time of processes, increase flexibility, and improve quality. Lean approaches help to eliminate waste in all its forms.

machine shop

A factory or workshop where metal is cut and shaped by machines. A machine shop is a type of job shop.

material handling

The strategy and devices used to move and store materials during the production cycle. Material handling should be minimized to reduce waste.

pokayoke

A Japanese term meaning mistake proofing. Pokayoke is an error prevention method.

product families

Groups of products that use similar machines or processes during manufacture. Grouping products according to family simplifies process flow charting.

project shop

A manufacturing facility that produces large items by bringing the machines and materials to the project.

pull system

A material management system in which parts are not delivered to machines until they are needed. Pull systems are based on actual demand for parts.

pull systems

A material management system in which parts are not delivered to machines until they are needed. Pull systems are based on actual demand for parts.

push system

A production method based on keeping up with preset inventory levels or with due dates for customer orders. Push systems are not based on customer demands.

retooling

The changing of machinery, fixtures, and tools for the production of a new part. Retooling takes place before new product runs begin.

setup reduction

A lean effort that uses standardization to reduce the time it takes to perform retooling.

soldering

A joining method that uses a heated filler metal to create a joint between metal parts. The filler metal is melted at temperatures below 840° F (450° C).

takt time

The ideal pace of production required to meet demand and consumption. Takt time is the number of work minutes per day divided by the number of work orders per day.

total productive maintenance

TPM. An approach used in manufacturing to increase production and reduce all forms of waste. TPM involves continuous attention to the conditions of production machinery and facilities.

universal product codes

UPC. A combination of a number and a series of parallel lines, known as a barcode, that appears on consumer packaging and is used in some shops as kanban.

waste

Any thing or process that does not add value to a product. Scrap is the most common form of waste.

workholding

The process of securely supporting, locating, and clamping a workpiece for a manufacturing operation.