The Five S's
The first practice mentioned here sprang from the same Japanese system that originally gave birth to lean manufacturing. The five S's is a methodology for organizing, cleaning, developing, and sustaining a productive work environment to create a workspace that is more organized and efficient. The rationale behind the five S's is that a clean workspace provides a safer, more productive environment for employees and promotes good business. The five terms beginning with "S" are manual disciplines employees should use to create a workplace suitable for lean production. The first term, sort (seiri in Japanese), means to separate needed items from unneeded ones and remove the latter. The second term, simplify, straighten, or set in order (seiton in Japanese) means to neatly arrange items for use. Shine, sweep, or scrub (seiso in Japanese) means to clean up the work area to establish ownership and responsibility, while standardize, systemize, or schedule (seiketsu in Japanese) means to standardize efforts as checklists, so as to practice the preceding three principles of sort, simplify, and scrub on a daily basis. Finally, sustain (shisuke in Japanese) means to always follow the first four S's so as to create a disciplined culture that practices and repeats the Five S principles until they become a way of life for employees.
Visual Controls
In terms of tools, lean manufacturing tends to focus heavily on visual controls to make life straightforward for operators and to avoid errors. Visual control requires that the entire workplace is set up with visible and intuitive signals that allow any employee to instantaneously know what is going on, understand any process, and see clearly what is being done correctly and what is out of place. Typical visual control mechanisms include warning signs, lockout tags, labels, and color-coded markings. One example is andon, an electronic board that provides visibility of floor status as well as information to help coordinate the efforts to linked work centers, through signal lights that are green (for "running"), red (for "stop"), and yellow (for "needs attention"). The primary benefit of visual control is that it is a simple and intuitive method that shows an employee quickly when a process is functioning properly and when it is not.
Standardized Work
Knowing which processes to perform is as important as knowing when they are functioning properly. To ensure that the required product quality level, consistency, effectiveness, and efficiency are realized, documented step-by-step processes, or standard operation procedures (SOP), are needed to define the standardized work necessary to reduce errors and touch times. Standardized work is one of the most overlooked tools of lean manufacturing, despite entailing the useful creation and documentation of clearly defined operations for both workers and machines. Such clearly defined operations allow manufacturers to apply best practices to manufacturing processes. Standardized work also provides the foundation for continuous improvement, since documented processes can be more easily analyzed and improved. To define standardized work, SOPs should use pictures, words, tables, symbols, colors, and visual indicators to communicate a consistent, intuitive message to diverse workgroups. Such graphical instructions, also known as operation method sheets (OMS), explain each step in the sequence of event (SOE) defined for a given production line, and can design and produce visual work instructions on paper or on screen.
Mistake Proofing
As continual improvement is one of the primary concepts behind lean manufacturing, mistake proofing, or poka-yoke in Japanese, is an important waste reduction tool. Mistake proofing is an essential failsafe activity to prevent errors at their source. In simple terms, mistake proofing is any device, mechanism, or technique that either prevents a mistake from being made or makes the mistake obvious so as to avoid a product defect. The objective of mistake proofing is either to prevent the cause of defects in manufacturing or to ensure that each item can be inspected cost-effectively so that no defective items reach downstream processes. For example, in an assembly operation, if each correct part is not used, a sensing device detects that a part was unused and shuts down the operation, thereby preventing the assembler from moving the incomplete part to the next station or beginning another operation.
Lean manufacturing further requires manufacturers to address equipment productivity issues through the adoption of total productive maintenance (TPM), which is a set of techniques, originally pioneered by Denso in the Toyota Group in Japan, that consists of corrective maintenance and maintenance prevention, plus continual efforts to adapt, modify, and refine equipment to increase flexibility, reduce material handling, and promote continuous flows (see Lean Asset Management—Is Preventive Maintenance Anti-lean?). TPM is operator-oriented maintenance that involves of all qualified employees in all maintenance activities. Its goal, hand in hand with the aforementioned five S's, is to ensure resource availability by eliminating machine-related accidents, defects, and breakdowns that sap efficiency and drain productivity on the factory floor. This includes setup and adjustment losses, idling and minor stoppages, reduced operating speeds, defects, rework, and startup yield losses.
Machine breakdown is a critical issue for the shop floor, as in a lean environment one machine going down can stop the entire production line or flow. Accordingly, TPM and other advanced enterprise asset management (EAM) options increase equipment reliability, and thus improve availability, reduce downtime, reduce product scrap (and wasted time managing that scrap), and increase machine tolerances (and consequently quality). As a further aid, diagnostics management features can automatically identify situations where the current maintenance strategy is not working and trigger a continuous improvement review. This often requires support for reliability driven maintenance (RDM), which can underpin the TPM strategy (see Reliability Driven Maintenance—Closing the CMMS Value Gap?). Finally, enterprise systems that can synchronize maintenance and production planning should maximize the available production time and contribute towards greater throughput and overall equipment effectiveness (OEE).
Simulation is another tool to help reduce maintenance-related waste. By supporting simulation, advanced service management systems typically include maintenance scheduling based on production plans, with automated update of the maintenance schedule based on actual finished production (with electronic links into the equipment's own runtime meters to schedule maintenance). The idea is to eliminate the following "big six" maintenance-related wastes.
1. Equipment downtime
2. Setup and adjustments
3. Minor stoppages or idleness
4. Unplanned breaks
5. Time spent making rejected product due to machine error
6. Rejects during start ups
Cellular Manufacturing
Moving from maintenance to manufacturing processes, the lean philosophy traditionally depends on cellular manufacturing, which is a manufacturing process that produces families of parts within a single line or cell of machines controlled by operators who work only within the line or cell. Manufacturing cells, arranged to ergonomically minimize workers' stretching and reaching for parts, supplies, or tools to accomplish the task, often replaced traditional, linear production lines to help companies prroduce products in smaller lot sizes, ensure a more continuous flow, and improve product quality. A related concept, nagara, is the Japanese term used to depict a production system where seemingly unrelated tasks can be produced by the same operator simultaneously. Nowadays, however, lean thinking is moving beyond pure cell- and product grouping-based production.
The first practice mentioned here sprang from the same Japanese system that originally gave birth to lean manufacturing. The five S's is a methodology for organizing, cleaning, developing, and sustaining a productive work environment to create a workspace that is more organized and efficient. The rationale behind the five S's is that a clean workspace provides a safer, more productive environment for employees and promotes good business. The five terms beginning with "S" are manual disciplines employees should use to create a workplace suitable for lean production. The first term, sort (seiri in Japanese), means to separate needed items from unneeded ones and remove the latter. The second term, simplify, straighten, or set in order (seiton in Japanese) means to neatly arrange items for use. Shine, sweep, or scrub (seiso in Japanese) means to clean up the work area to establish ownership and responsibility, while standardize, systemize, or schedule (seiketsu in Japanese) means to standardize efforts as checklists, so as to practice the preceding three principles of sort, simplify, and scrub on a daily basis. Finally, sustain (shisuke in Japanese) means to always follow the first four S's so as to create a disciplined culture that practices and repeats the Five S principles until they become a way of life for employees.
Visual Controls
In terms of tools, lean manufacturing tends to focus heavily on visual controls to make life straightforward for operators and to avoid errors. Visual control requires that the entire workplace is set up with visible and intuitive signals that allow any employee to instantaneously know what is going on, understand any process, and see clearly what is being done correctly and what is out of place. Typical visual control mechanisms include warning signs, lockout tags, labels, and color-coded markings. One example is andon, an electronic board that provides visibility of floor status as well as information to help coordinate the efforts to linked work centers, through signal lights that are green (for "running"), red (for "stop"), and yellow (for "needs attention"). The primary benefit of visual control is that it is a simple and intuitive method that shows an employee quickly when a process is functioning properly and when it is not.
Standardized Work
Knowing which processes to perform is as important as knowing when they are functioning properly. To ensure that the required product quality level, consistency, effectiveness, and efficiency are realized, documented step-by-step processes, or standard operation procedures (SOP), are needed to define the standardized work necessary to reduce errors and touch times. Standardized work is one of the most overlooked tools of lean manufacturing, despite entailing the useful creation and documentation of clearly defined operations for both workers and machines. Such clearly defined operations allow manufacturers to apply best practices to manufacturing processes. Standardized work also provides the foundation for continuous improvement, since documented processes can be more easily analyzed and improved. To define standardized work, SOPs should use pictures, words, tables, symbols, colors, and visual indicators to communicate a consistent, intuitive message to diverse workgroups. Such graphical instructions, also known as operation method sheets (OMS), explain each step in the sequence of event (SOE) defined for a given production line, and can design and produce visual work instructions on paper or on screen.
Mistake Proofing
As continual improvement is one of the primary concepts behind lean manufacturing, mistake proofing, or poka-yoke in Japanese, is an important waste reduction tool. Mistake proofing is an essential failsafe activity to prevent errors at their source. In simple terms, mistake proofing is any device, mechanism, or technique that either prevents a mistake from being made or makes the mistake obvious so as to avoid a product defect. The objective of mistake proofing is either to prevent the cause of defects in manufacturing or to ensure that each item can be inspected cost-effectively so that no defective items reach downstream processes. For example, in an assembly operation, if each correct part is not used, a sensing device detects that a part was unused and shuts down the operation, thereby preventing the assembler from moving the incomplete part to the next station or beginning another operation.
Lean manufacturing further requires manufacturers to address equipment productivity issues through the adoption of total productive maintenance (TPM), which is a set of techniques, originally pioneered by Denso in the Toyota Group in Japan, that consists of corrective maintenance and maintenance prevention, plus continual efforts to adapt, modify, and refine equipment to increase flexibility, reduce material handling, and promote continuous flows (see Lean Asset Management—Is Preventive Maintenance Anti-lean?). TPM is operator-oriented maintenance that involves of all qualified employees in all maintenance activities. Its goal, hand in hand with the aforementioned five S's, is to ensure resource availability by eliminating machine-related accidents, defects, and breakdowns that sap efficiency and drain productivity on the factory floor. This includes setup and adjustment losses, idling and minor stoppages, reduced operating speeds, defects, rework, and startup yield losses.
Machine breakdown is a critical issue for the shop floor, as in a lean environment one machine going down can stop the entire production line or flow. Accordingly, TPM and other advanced enterprise asset management (EAM) options increase equipment reliability, and thus improve availability, reduce downtime, reduce product scrap (and wasted time managing that scrap), and increase machine tolerances (and consequently quality). As a further aid, diagnostics management features can automatically identify situations where the current maintenance strategy is not working and trigger a continuous improvement review. This often requires support for reliability driven maintenance (RDM), which can underpin the TPM strategy (see Reliability Driven Maintenance—Closing the CMMS Value Gap?). Finally, enterprise systems that can synchronize maintenance and production planning should maximize the available production time and contribute towards greater throughput and overall equipment effectiveness (OEE).
Simulation is another tool to help reduce maintenance-related waste. By supporting simulation, advanced service management systems typically include maintenance scheduling based on production plans, with automated update of the maintenance schedule based on actual finished production (with electronic links into the equipment's own runtime meters to schedule maintenance). The idea is to eliminate the following "big six" maintenance-related wastes.
1. Equipment downtime
2. Setup and adjustments
3. Minor stoppages or idleness
4. Unplanned breaks
5. Time spent making rejected product due to machine error
6. Rejects during start ups
Cellular Manufacturing
Moving from maintenance to manufacturing processes, the lean philosophy traditionally depends on cellular manufacturing, which is a manufacturing process that produces families of parts within a single line or cell of machines controlled by operators who work only within the line or cell. Manufacturing cells, arranged to ergonomically minimize workers' stretching and reaching for parts, supplies, or tools to accomplish the task, often replaced traditional, linear production lines to help companies prroduce products in smaller lot sizes, ensure a more continuous flow, and improve product quality. A related concept, nagara, is the Japanese term used to depict a production system where seemingly unrelated tasks can be produced by the same operator simultaneously. Nowadays, however, lean thinking is moving beyond pure cell- and product grouping-based production.
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