Single Minute Exchange of Die (SMED)

Single Minute Exchange of Die (abbreviated SMED) is one of the many lean manufacturing techniques designed to speed up product switching processes and decrease wasteful manufacturing practices. SMED is essential in increasing productivity while reducing waste levels in manufacturing operations.

Shigeo Shingo, an internationally acclaimed industrial engineer and expert on the Toyota Production System, devised SMED. His efforts reduced changeover time for transfer stamping machines from hours to 180 seconds, saving both time and resources for production lines alike.

What is SMED?

SMED is an innovative process that significantly shortens changeover times between production runs. This is achieved by categorizing changeover elements as internal or external to machine operation time and then adapting or simplifying them during normal machine operations - thus significantly decreasing changeover times, often down to mere minutes!

An SMED project can lead to substantial savings for any company. For instance, an action figure manufacturer selling them at $20 each could lose one sale every 60 seconds as they switch from mold to mold; with proper planning and execution, an SMED project may reduce this to 10 or fewer seconds!

An SMED pit crew can serve as an analogy for SMED, with process setups and changes representative of pit stops. Pit crews employ various strategies to streamline their work - prepositioning all tools before beginning an actual pit stop, using standard attachment points and methods, etc. Their aim should be to reduce tire swap times from 15 minutes to sub-10 seconds as quickly as possible.

SMED projects at manufacturing plants may involve switching products, moving between dies, modifying jigs, gauges, materials, and more to modify processes or modify equipment while it runs or shuts down; some steps may even need to be completed when the machine shuts down - SMED projects look at ways of streamlining or eliminating these steps to reduce changeover times from hours or days down to minutes (or single digits).

Once a baseline for your changeover process has been established, elements that can be completed while the machine runs are prioritized. Internal setup processes that remain are examined for opportunities for optimization and simplification, such as eliminating motion, waiting, adjustments, creating parallel operations, or standardizing hardware.

SMED can significantly decrease manufacturing costs by streamlining processes and reducing changeover times, improving OEE, increasing machine startup rates, and helping smaller lot sizes meet customer demand faster while reducing WIP and inventory levels.

What are the benefits of SMED?

SMED (short for "Simple Manufacturing Equipment Changeover") is an equipment changeover process developed in the 1950s by industrial engineer Shigeo Shingo to assist manufacturing companies in reducing inventory levels and boosting production efficiency. Lean practitioners use SMED in virtually every setting, from factories and fast food restaurants to offices.

SMED (Source for Manufacturing Excellence and Delivery) aims to eliminate non-value-adding procedures and streamline those remaining so teams can focus on only those critical steps needed for production efficiency and reduce waste while improving employee morale.

Initial die exchange processes were called Quick Die Change; however, Shingo later changed it to Single Minute Exchange of Die to reflect his goal of shortening setup times as much as possible. Unfortunately, "single minute" can be misleading since changeover procedures do not need to take only a minute; single-digit minutes (less than 10) would be more suitable.

SMED can save time, but its other advantages also include:

Reduced manufacturing costs. Shorter changeover times lead to reduced downtime periods and lower material, labor, and energy costs. Increased flexibility. Shorter changeover times give manufacturers more ability to produce just enough products at any time while decreasing inventory carrying costs and carrying costs.

Increased Quality. Rapid changeover times allow for quicker product switches with increased frequency, meaning higher levels of consistency in quality.

Implementing the SMED process can be difficult and complex, impacting every aspect of business operations. Training your team on new procedures to explain why they will increase efficiency is crucial to ensuring the transition runs smoothly; also, developing standard work instructions helps ensure everyone knows exactly what needs to be completed and when.

Last but not least is to reduce unnecessary motion by organizing storage. Hence, it is easier for team members to find what they need quickly, using point-of-use storage where appropriate and clearly labeling equipment settings. This will also help mitigate human error during context-switching processes.

How can SMED be implemented?

Once your team is prepared to implement SMED, they must become organized. Create a list of all the elements involved in changeover processes and prioritize which can be completed while running while others must wait offline; this can speed up transitioning to single-digit minute setup times as quickly as possible. Also, consider whether any elements can be done simultaneously, such as tool prep while another part is produced; similar to how NASCAR pit crews operate, this can streamline processes further while using easily accessible standard tools can simplify processes further.

Once you have documented all of the internal elements, the next step should be identifying waste - both motion-related and time-based. To do this, simplify procedures, remove steps, and eliminate interactions that are no longer needed; equipment modification may also be required; designing highly portable machines reduces interface requirements while modular components enable moving them quickly between production lines.

Finally, it's essential to establish an initial changeover time baseline. This will enable a comparison of SMED implementation results against those from other companies that have already adopted the method. It should also recognize any Hawthorne Effect that might help your changeover times improve simply through watching and learning from the process itself.

SMED can be applied effectively in factories that manufacture action figures for children, which sell for about $20 each. The manufacturer can produce one every 60 seconds, so each time they switch molds, they lose out on sales worth $20.

To reduce these costs, the company started employing SMED strategies, such as switching from manual mold changes to one-touch systems for mold changes and cutting preparation time down from hours to minutes; lean manufacturing practices allowed them to achieve just-in-time production goals and cut inventory levels significantly.

What are the challenges of SMED?

SMED strives to reduce the time needed to change equipment from one product to another by identifying and eliminating unnecessary steps from its process and changing internal setup elements into external ones.

Industrial engineers have long understood the need to shorten changeover times. Shigeo Shingo, an engineer who worked at Toyota, developed the SMED system in the 1970s; quickly becoming popular, its usage has resulted in documented reductions of changeover time averaging 94%.

SMED can be invaluable for shortening changeover times, but companies must remember that it will only solve some of their production woes. To maximize its use and reap maximum returns from SMED, companies should focus on optimizing human and machine processes as part of a comprehensive approach to improvement.

Human improvements can be accomplished through organization and preparation, while machine improvements may involve engineering or optimization. Examples of human improvements would be creating standard work instructions, placing tools near the changeover area for easy access, labeling equipment settings, and eliminating wasteful motion.

Once a company has identified areas to improve, it must devise a plan for implementing SMED. This may involve assigning a project leader, holding brainstorming sessions, and training employees on how the new process works. Furthermore, they should set a timeline for reaching their desired results.

An unfortunate hazard of SMED processes is their tendency to prioritize speed over quality, leading to rushed or incomplete changeovers that compromise productivity and increase the risk of defects. Furthermore, it should be remembered that any successful implementation will still involve some downtime - even if only for minutes at a time.

Implementing SMED requires considering that learning its processes may take some time for teams, mainly if changes to production are significant. To combat this, new employees should receive training on SMED before beginning production work; this will give them a deeper understanding of its workings and facilitate more straightforward adaptation.

Pros of Single Minute Exchange of Die (SMED)

• Reduced Changeover Time: The primary benefit of SMED is the drastic reduction in the time required for changeovers.
• Increased Productivity: With quicker changeovers, more time is available for actual production, increasing overall productivity.
• Cost Savings: Reduced downtime leads to lower operational costs and increased profitability.
• Flexibility: Faster changeovers allow for greater flexibility in production schedules and the ability to respond to market demands.
• Improved Quality: A well-executed SMED program can also lead to improvements in product quality.
• Lean Manufacturing: SMED is a critical component of lean manufacturing, contributing to waste reduction and efficiency.
• Better Utilization of Resources: Faster changeovers mean better utilization of machines and manpower.
• Competitive Advantage: Companies that successfully implement SMED often gain a competitive edge regarding speed and responsiveness.
• More straightforward Scheduling: Reduced changeover times make production scheduling more accessible and flexible.
• Employee Engagement: Implementing SMED often involves teamwork and problem-solving, which can boost employee engagement.

Cons of Single Minute Exchange of Die (SMED)

• Initial Costs: Implementing SMED may require investment in new tools or equipment.
• Training Requirements: Employees need to be trained in the SMED methodology, which can be time-consuming.
• Complexity: While the concept is simple, the implementation can be complex and require detailed analysis.
• Resistance to Change: As with any new process, there may be resistance from employees accustomed to the old ways of doing things.
• Limited Applicability: SMED is most effective when frequent changeovers are required; it may be less beneficial in other scenarios.
• Risk of Rushing: The focus on speed could lead to mistakes or oversights.
• Dependency on Skilled Workers: The effectiveness of SMED often depends on the skill and cooperation of the workforce.
• Short-term Disruptions: Initial implementation may cause disruptions in the regular workflow.
• High Expectations: Promising dramatic improvements can lead to high expectations, and failure to meet them can be demoralizing.
• Ongoing Maintenance: SMED is not a one-time activity; it requires constant effort to maintain and improve the process.

Eight Pillars of Total Productive Maintenance

Total Productive Maintenance (TPM), in contrast with reactive maintenance, which waits until equipment breaks before taking action, takes preventative steps to boost machine performance and prevent slowdowns, defects, or speed losses. TPM strives to maximize machine utilization while decreasing delays, imperfections, or speed losses.

TPM utilizes lean manufacturing and 5S principles to organize and standardize facility procedures while framing maintenance as an integral element of overall equipment effectiveness (OEE).

Identifying Problems

Total Productive Maintenance (TPM) is a lean manufacturing philosophy that seeks to achieve near-perfect production without small stops, breakdowns, defects, or accidents. TPM involves all facility employees, from floor plant technicians to senior facility managers, working collaboratively to improve equipment availability and quality while using preventive maintenance techniques and featuring eight pillars.

Step one in any TPM program should be to identify issues that could impede production and take corrective actions. This involves an in-depth evaluation of the current production process, including a review of downtime losses, defect losses, and speed losses and identifying the root causes of these losses.

Problem-solving techniques combined with automated tools like condition monitoring can be used to achieve this objective. Condition monitoring provides real-time information on equipment status, allowing facilities to quickly pinpoint its root cause (such as excessive wear and tear ) to prioritize future actions and limit downtime.

Preventative maintenance checklists can also help identify problems by increasing employee awareness of what must be done and when. They also reduce the time and effort needed for routine tasks performed by maintenance personnel.

Problems that impede production can often be easily identifiable, for example, when a machine stops functioning due to sensor or power surge issues. Other issues, however, may be more challenging to detect or pinpoint, such as improper operator training, lack of organization in the workplace, and inconsistent inspection schedules.

TPM provides an effective solution to these issues by shifting responsibility for basic equipment upkeep to its primary users: machine operators. This enables them to perform autonomous maintenance like cleaning and safety checks without needing assistance from technicians - potentially cutting production losses significantly while improving overall equipment effectiveness (OEE).

TPM stresses the significance of streamlining administrative functions to eliminate wasteful organizational practices, such as expediting order processing, purchasing, and scheduling, to avoid delays in finding necessary parts or materials for production.

Preventative Maintenance

Total Productive Maintenance is a framework for optimizing facility maintenance to eliminate resource waste, employee accidents, product defects, and unplanned downtime. However, its success relies upon effective maintenance practices used to support it; an excellent CMMS makes identifying issues simple while tracking maintenance and repair costs, helping avoid breakdowns or unexpected repairs that might otherwise cost more than anticipated.

Step one of implementing Total Productive Maintenance is setting goals for your most crucial assets and equipment using quantifiable and measurable metrics. For instance, if a critical piece of machinery consistently breaks down or produces products below quality standards, set an annual goal to reach zero production losses; this will motivate your employees for continuous improvements and help get your TPM program off the ground.

Once your targets have been set, the next step should be creating a preventative maintenance schedule for your most valuable equipment. Begin with the frequency the manufacturer recommends, adjusting as necessary to avoid over or under-maintain them. In addition, create a preventative maintenance checklist to keep track of team tasks and ensure all required tasks are accomplished; mandatory charges should be addressed immediately, while non-mandatory ones may be completed without risking equipment failure or productivity losses.

After establishing a preventive maintenance routine, training employees is critical for increasing autonomy and decreasing over-reliance on reactive maintenance. A CMMS can assist this effort by offering quick access to maintenance logs and controlling inventory. Hence, you always have spares and centralizing information about each asset (OEM recommendations, fault patterns, inspection procedures).

Once your employees are trained, they should begin identifying problems and taking measures to address them using the practice of Kaizen (continuous improvement to optimize processes and eliminate waste). As you implement changes, you must measure progress to know which areas need further improvement while tracking what changes work well and which require additional work from your team.

Restoring Equipment to Prime Operating Condition

Each piece of equipment must be in top operating condition to maximize performance. This can be accomplished through adhering to TPM principles to eliminate waste in manufacturing. TPM helps eliminate unscheduled downtime, scrap, rework, and product quality issues that adversely impact equipment failure that require costly repairs or replacements.

TPM requires all employees to assume some responsibility for equipment maintenance management to improve equipment availability, allowing everyday users to take on essential upkeep duties like cleaning, lubrication, and inspection while freeing up facility and maintenance staff to focus on more critical tasks. This allows people with intimate knowledge of equipment like cleaning machines to take ownership of basic upkeep such as cleaning, lubricating, and inspecting them themselves while freeing facility and maintenance teams up for more pressing duties.

Step two of TPM involves identifying and addressing significant losses in production processes. A cross-functional team of employees should gather to conduct root cause analysis on all available data sets to pinpoint areas that should be considered. Once problem areas have been identified, an action plan can be developed to address them.

Training operators on identifying and fixing issues quickly and devising simple preventative maintenance procedures they can promptly implement can also be very beneficial. Visuals that track equipment health and performance, such as color-coded charts showing when lubrication should occur, may help identify any under or over-lubrication problems; using visuals to spot potential problems early can improve OEE while reducing downtime.

Implementing Total Productive Maintenance can be challenging, yet can yield significant improvements to manufacturing processes. By eliminating six big losses in production, TPM can increase profitability through lower operational costs and improved product quality while raising worker morale by placing maintenance as part of a company's core value system.

Measurement

An effective total productive maintenance implementation relies on robust measurement and data collection techniques. This involves collecting and analyzing production and maintenance data to assess each piece of equipment's status and identify any critical problems while simultaneously identifying significant losses - the six leading causes of failure in industrial environments that must be addressed through root cause analysis of OEE data to pinpoint its causes and solve any related issues.

TPM seeks to shift responsibility for equipment maintenance away from an independent maintenance department and onto all plant personnel by assigning tasks typically reserved for dedicated crews, such as cleaning and lubricating equipment, performing regular safety checks, and identifying signs of trouble early. This approach blurs the distinction between manufacturing and maintenance by investing every employee in its success - making everyone part of an organization's machinery's success!

TPM may seem challenging to implement in a factory environment, but companies that commit themselves and take the necessary time and care will see results over time. TPM can reduce equipment stoppage costs while increasing productivity, resulting in greater profits for your company.

TPM calls for developing a culture of continuous improvement, or Kaizen. This means gathering small groups of workers to brainstorm ways to enhance equipment and processes within their facility, including finding early adopters to lead this initiative and spread knowledge throughout.

Though TPM may seem ideal for production facilities, its applications extend to offices and administrative functions. By applying TPM tools in these areas, businesses will find that waste reduction increases along with organizational efficiency in procurement, order processing, scheduling, and more consistent production processes that ultimately boost worker morale and quality of life.

Pros of Total Productive Maintenance (TPM)

• Reduced Downtime: TPM aims to minimize equipment downtime, increasing productivity and efficiency.
• Improved Quality: By maintaining equipment in optimal condition, TPM helps produce high-quality products.
• Employee Involvement: TPM encourages the involvement of all employees, not just maintenance teams, in equipment upkeep.
• Cost Savings: Reduced downtime and fewer defects lead to significant cost savings in the long run.
• Enhanced Safety: Regular maintenance checks help identify potential safety hazards, reducing accidents.
• Increased Equipment Life: TPM extends the life of machinery and equipment, reducing the need for frequent replacements.
• Better Planning: TPM allows for better planning and scheduling as equipment failures are minimized.
• Competitive Advantage: Companies that implement TPM effectively often gain a competitive edge in quality and cost.
• Resource Optimization: TPM ensures that human and machine resources are used to their full potential.
• Cultural Change: TPM fosters a culture of continuous improvement and responsibility among employees.

Cons of Total Productive Maintenance (TPM)

• Initial Costs: Implementing TPM can be costly, especially for training and possibly upgrading equipment.
• Time-Consuming: TPM requires a long-term commitment and can be time-consuming to implement effectively.
• Complexity: TPM involves multiple activities like autonomous maintenance, planned maintenance, and quality maintenance, making managing it complex.
• Resistance to Change: Employees may resist the new responsibilities and changes that TPM brings.
• Dependency on Employee Skills: The success of TPM is highly dependent on the skills and commitment of the workforce.
• Potential for Over-Maintenance: There's a risk of spending too much time on maintenance activities, affecting productivity.
• Limited to Manufacturing: TPM is most effective in manufacturing settings and may not apply to all types of businesses.
• Requires Cultural Shift: Successful TPM implementation may require a change in organizational culture, which can be challenging.
• Risk of Inconsistency: Withorts can become inconsistent over time without proper train consistent-through.
• High Expectations: Promising significant improvements can lead to high expectations, and failure to meet them can be demotivating.