Single-minute exchange of die | Doing a kind of “readjustment” and “retooling” yourself can be an amazing adventure and creative act. The question is how to approach this.
In comparison with the personal and home situation, where the timing of the “dismantling” is not so critical, in production, the rapid reconfiguration of equipment is tied to the needs of the business. You can’t get cranky here (I’ll do it tomorrow) because time is money. It is necessary to reconfigure the equipment as quickly as possible and, most importantly, according to the needs of the process / client.
The need for equipment readjustment is a natural desire to produce goods of different assortments. Quick readjustment of equipment is necessary if you need to produce small batches of products. The faster and more economical the readjustment process takes place, the less the company loses from equipment downtime, expressed in real money.
What is SMED?
Single-minute exchange of die (SMED) is a lean manufacturing technique that significantly reduces inefficiencies in a manufacturing process.
This concept focuses on the quick change over transactions in product processing. It may be machine parts, current product to next product, or even readjustment of equipment.
This is a fast and effective switching method; The concept of fast switching states that all transitions (and start-ups) can and should take less than 10 minutes. Hence the term single minute. Therefore, it is also known as single-minute rapid mold change method, 10-minute mold change method, rapid operation changeover, etc.
Which is a method used to solve the difficulty of rapid conversion and adjustment of equipment – shortening the possible changeover time to the shortest (instant changeover). It can quickly switch from one ongoing production process to the next. It can and often is used to start a program and get it running quickly with minimal waste.
How does fast switching work?
So, first of all, we must understand what switching is and what to switch; Switching refers to the time interval between the last qualify product of the previous variety and the first qualify product of the next variety. The switching time is mainly composed of four parts: preparation time, switching operation time, adjustment time, and finishing time.
Then as far as the process of switching is concern, the switching can be divided into internal operations and external operations; Internal operation refers to the operation content that requires equipment / machine shutdown to be implemented, also known as internal switching, which includes dismantling old molds, installing new molds, and adjusting and first inspection; External operations refer to the work that can be carried out without the shutdown of equipment/machines, including pre-external switching operations (pre-switching preparations, such as preparing tools, molds, materials, etc.) and post-external switching operations (finishing work after switching, such as on-site cleaning, mold storage, etc.).
Basic concepts
The time to change the mold is the sum of the internal operation and the external operation. External operation refers to the mold change (adjustment) work that can be carried out during the operation of the equipment, such as placing and disassembling the equipment; Internal operations are mold change operations that can only be performed when the equipment is down, such as the first product end-of-line inspection, filling, installation or reloading of equipment.
Why are Single-minute exchange of die so popular?
One of the reasons SMED has become so popular is that Shingo is said to be able to use it to increase the efficiency of companies by an average of 94%. Combining with its other benefits, it’s clear why so many businesses are trying to replicate Shingo’s success.
Benefits of Single-minute exchange of die include:
- Reduce manufacturing costs
- Greater efficiency
- Smaller batches
- Lower inventory levels
- Improve responsiveness to customer needs
- Run startups more smoothly
- and more…
However, despite all these advantages, SMED is not suitable for all companies. You should carefully consider whether it is right for you, especially if you are a business operating outside.
When should you consider SMED?
Despite its many benefits, Single-minute exchange of die is not a magic wand. It has its limitations, which can affect your company’s use cases. Therefore, before deciding to incorporate it into your operations, you should consider the following:
Do you have a process that SMED can improve?
As mentioned earlier, SMED is best suited for manufacturing. It focuses primarily on large assets, recurring or one-time work orders.
Do you have a way to follow standardized processes?
SMED can only work efficiently after all the work requirements have been fully and flawlessly completed. This makes SMED particularly difficult to implement due to the human factor. Oversights, errors, and unfamiliarity with the process can all affect the results you’ll see.
If you answered yes to both questions, then you can start thinking about incorporating SMED into your corporate activities.
Fast readjustment eliminates losses
Lean manufacturing, focused on reducing production losses, offers SMED (Single-Minute Exchange of Dies) technology as a powerful working tool for quick adjustment and re-equipment. The method was developed for more than 19 years by Shigeo Shingo (Toyota) and continues to evolve to this day. Today, we can say that the use of the SMED method in many industries has led to an average 94% reduction in the time of adjustment of equipment. That’s the average. But, of course, the most impressive are the “squeezes” of hours in minutes, and minutes in seconds. A classic example is the work of the Formula 1 pit stop team.
The introduction of the Single-minute exchange of die method at the enterprise provides production with the necessary flexibility and competitiveness. It is also important that the rapid readjustment using the SMED method significantly reduces the readjustment time itself while reducing labor costs. At the same time, useless, unprofitable actions from the classic “seven losses” of lean production are being reduced.
What are the goals of the introduction of the rapid readjustment methodology?
- Reduced equipment downtime losses
- Possibility to produce in smaller batches
- More flexible production planning
- Quick response of the assortment to market needs
- Reduction of inventory and work-in-progress due to continuity of the production process
- Better operation of the equipment by standardizing the processes of its care and replicating the best methods of readjustment, developed in the enterprise
SMED Implementation Methodology Offers Six Steps to Eliminate Read get Losses
Step 1. Select a pilot object and monitor the readjustment process with the recording of the actions of performers using video. For this initial data collection, you need to:
- Make a list of works (operations) performed during the readjustment;
- Identify differences in the actions of performers;
- Assess the duration of operations and note the most rational techniques.
Step 2. Separation of readjustment operations into INTERNAL, performed exclusively when the equipment is STOPPED, for example, replacing the filtration system or die, and EXTERNAL, performed BEFORE stopping or AFTER starting the equipment, for example, various actions to search for sets of parts, work with instructions, clean equipment, etc. To do this:
- Make a preliminary list of ALL adjustment works, it is more convenient to do this using video recordings of the process and their further analysis;
- To develop decisions regarding the adjustment actions performed during the operation of the equipment, i.e. external, asking the question: “Can this action be performed with the equipment running?”;
- Eliminate obvious losses associated with the search for tools, repair of faulty equipment, sharpening of the tool, waiting for the supply of the necessary materials or tools;
- Visualisation the storage locations of replacement parts and make them easy to move.
Step 3. Reduced INTERNAL readjustment time. To do this:
- Involve additional adjusters to reduce the readjustment time, practice parallel operations, because working equipment creates more value than a simple readjustment;
- Distribute and consolidate operations between adjusters, which can already reduce the readjustment time by 45-55%;
- Pay special attention to the balance and coherence of their actions, as with well-organized teamwork (the analogy of dance works well);
- Remember that the ideal readjustment is one-touch readjustment.
Step 4. Reduction of EXTERNAL changeover time. To ensure that the readjustment of one machine does not lead to downtime of another, you should:
- Reschedule the site: quick readjustment involves minimal and convenient movements of both the operator and the equipment;
- Rationally organize the storage of all elements of the tooling, visualize the storage location, because wasting time searching for the necessary part with SMED is unacceptable;
- Use operator-friendly lifting vehicles and devices to reduce physical exertion.
Step 5. Reduction of adjustment and adjustment time of parameters. What is important:
- Fine-tuning operations on traditional equipment, without CNC, are the most difficult to algorithmize and take up to 50% of the readjustment time;
- Determine the reasons for the need for adjustment (accumulation of errors, imperfection of regulatory and technical documentation, insufficient stability of equipment / tooling, imperfection of adjustment mechanisms, measuring tools);
- Reasons to analyse in close cooperation between operators and adjusters and technical services;
- The best solution is to move the adjustment to an external readjustment (out-of-device adjustment of the tool).
Step 6. Regulation and standardization of the readjustment process.
The solutions found for quick readjustment should be recorded in writing, which is necessary for their exact observance, for control by managers and self-control. What is fixed:
- Readjustment time, shift schedules to establish the moment when the external readjustment begins;
- The readjustment process itself is regulated: there are instructions for reconfiguration, technological maps of readjustment have been created;
- Storage places for tooling and tools are systematized and visually understandable.
As well as:
- apply specialized devices for out-of-machine adjustment of tools;
- use samples, templates, precise measuring tools;
- introduce means of small mechanization;
- monitor compliance with readjustment schedules and internal and external readjustment actions.
When implementing the Single-minute exchange of die quick readjustment system at the enterprise, lean manufacturing tools such as:
- Standardization
- Visualization
- Error prevention
- Technical improvements
- Eliminating actions that do not bring value
In addition, an important factor in the implementation of Single-minute exchange of die at the enterprise should be called the improvement of the skills of well-coordinated teamwork of employees.
What issues should be discussed in the team?
For example, revising the checklist of internal and external readjustment operations:
- check operations – perhaps some of them are mistakenly perceived as internal;
- find ways to turn such operations into external ones.
When implementing the SMED quick readjustment system at the enterprise, lean manufacturing tools such as:
To improve internal operations, it is enough to ask a number of questions, the answers to which will help to quickly understand where the problems in production are:
- is this the best time for surgery?
- can it be done at another time?
- is this the best person for surgery?
- can someone do the work for him?
- is it the best place to do the work?
- is it possible to do this at another workplace?
Discussions on the effectiveness of external operations can result in useful tools such as:
- preparation of checklists;
- carrying out functional checks;
- use of parallel operations.
The use of such a potentially effective tool as Single-minute exchange of die in the practice of the enterprise, in addition to a powerful improvement in work processes, contributes to the involvement of all participants in it: from management and project manager to direct executors.