Single minute exchange of die
Single Minute Exchange of Die (SMED) - is a tool change within a one-digit number of minutes; method of diagnosing and improving production processes in the processing industry initiated in 1950. by Shingeo Shingo - one of the most prominent contemporary representatives of Japanese science and the practice of organization and management.
The SMED method process
The key issue is the use of methods for improving production processes (e.g. SMED) and production stock management methods (e.g. JIT) is to find the optimum cost of production. Delays in the planned production process often result from machine and equipment failures. In addition, there are delays due to the reproduction of a planning system that does not react to the environment with a planned horizon, which is measured not in hours but rather in weeks. Therefore, the implementation of the universal method of planning and production control - Just In time requires a risk minimization strategy in cooperation with SMED, KANBAN, Total Productive Maintenance (TPM) and TQM.
The process of retooling machines and devices consists of:
- preparation of disassembly, material verification,
- disassembly and assembly of tools,
- centering and setting dimensions and other parameters,
- making test copies of semi-finished products.
The reduction of the retooling time of the machine increases the time intended for production and at the same time allows to reduce the size of production batches, the quantity of stocks and, as a result, decreases production costs.
The stages of SMED implementation
The implementation of the SMED system is divided into three stages
The first stage is the separation of internal operations from external operations. Thanks to this stage, operations that can be made while machines are being operated are identified, which saves time. With the division of activities, the recording of the film from the course of preparatory operations is checked, which allows you to accurately analyze the activities that are part of the individual operations. Often, checklists are also used, which contain the necessary information about the instruments, tools and employees responsible for the execution of individual operations. These lists are developed for each operation.
In the second stage, try to convert internal operations to external operations. To do this, focus on the preparatory activities that were performed so far with the machines turned off, and find a way to do these activities without stopping production. Such a solution may be, among others, earlier conditions for carrying out the changeover operation. You can prepare it by:
- preparation of tools and elements that are subject to processing,
- determine the location of materials,
- heat the parts to the right temperature.
Reducing the changeover time can also standardize the tool that is used in production, so that you will not need to replace these tools frequently.
The conversion of internal operations into external activities is a difficult stage, it requires searching for new, unusual solutions. The creator of the SMED method presented a set of five questions that can help in this step:
- What is being done?
- Who does it?
- How does it work?
- Where is it done?
- When does it?
The third stage of the implementation of the SMED system is the comprehensive improvement of the rearming operation. This stage consists mainly of:
- improving the process of transport and storage of tools and materials,
- identifying activities that can be performed in parallel,
- searching for solutions that facilitate the assembly of individual elements and shorten its duration.
Techniques used in the SMED method
List of questions
- applies to all parts and operations necessary to replace the tool;
- includes a list of instrumentation, data on pressure, temperature and other setting parameters, numerical quantities for all measures and dimensions;
- it is based on double verification to detect faults in the conditions of the operation.
Verification board
- it complements the list of questions,
- allows you to verify the completeness of the elements necessary to make the changeover thanks to the parts and tools defined on it,
An attempt to function
- provides confirmation of the technical condition guaranteeing efficient operation,
- it postulates, among others, standardization of machines and devices, quick fixing of exchanged tools and their rational distribution, appropriate conversion preparation and the use of value analysis.
Examples of Single minute exchange of die
- In automotive assembly, when a machine must switch from producing one part to another, a SMED system can be used to reduce the amount of time required to exchange the dies. The dies are set up on their own separate machines and the parts can be produced in batches, allowing for the switchover to take place without any interruption to the main production line.
- In the food processing industry, SMED can be used to switch from one product to another quickly and efficiently. For example, a company may have several lines of production dedicated to different products. By using SMED, the production line can quickly switch between these products to optimize production and minimize downtime.
- In the electronics industry, SMED can be used to switch from one type of PCB to another. By having dedicated machines for each type of PCB, the switchover time can be significantly reduced, allowing for a faster production cycle.
Advantages of Single minute exchange of die
SMED (Single Minute Exchange of Die) is a production process improvement method that was developed in 1950 by Shingeo Shingo and is used in the processing industry. Advantages of this method include:
- Reduced set-up times: SMED reduces set-up times and prevents downtime, which can increase productivity and reduce costs.
- Increased flexibility: SMED allows production operations to be easily switched from one product to another, allowing for greater versatility and potentially higher profits.
- Improved quality control: SMED helps to reduce the risk of errors during production, ensuring that products are of the highest quality.
- Greater efficiency: SMED helps to make production operations more efficient, since the shorter production times can reduce waste and save resources.
- Less risk of injury: SMED reduces the risk of injury to workers, as the shorter production times can reduce the amount of heavy lifting and other physically demanding tasks.
Limitations of Single minute exchange of die
Single Minute Exchange of Die (SMED) is a tool used to reduce changeover times in manufacturing processes. While it is generally a successful method, there are a few limitations that must be taken into consideration. These include:
- Difficulty in developing a standard process: SMED requires a detailed and standardized process to be implemented in order for it to work effectively. This can be difficult to achieve, as there may be variations in the process that need to be taken into account.
- Time-consuming: SMED can be quite time-consuming when initially set up, as it requires detailed analysis and planning in order to achieve the desired results.
- Cost: As SMED requires additional training, equipment and materials, it can be costly to implement.
- Not suitable for all processes: SMED is not suitable for all processes, as some processes may require more complex or specialized equipment.
- Not suitable for all industries: SMED may not be suitable for all industries, as some processes may be too complicated for SMED to be applied.
Single Minute Exchange of Die (SMED) is a tool change within a one-digit number of minutes and a method of diagnosing and improving production processes in the processing industry initiated in 1950 by Shingeo Shingo. Other approaches related to SMED include:
- Just-in-Time (JIT) - a system of production and delivery of products on the production line in-time to meet customer demand.
- Total Productive Maintenance (TPM) - an approach to maintenance that maximizes the efficiency of the production process.
- Kanban - a system for managing the flow of materials in a production line.
- Kaizen - a philosophy of continuous improvement.
In summary, Single Minute Exchange of Die (SMED) is one of many approaches to improving production processes, including Just-in-Time (JIT), Total Productive Maintenance (TPM), Kanban, and Kaizen.
Single minute exchange of die — recommended articles |
Line balancing — Quality control — Production cycle — Quality inspection — Total productive maintenance — Overall equipment effectiveness — Time study — Group technology — Pull system |
References
- Carrizo Moreira, A., & Campos Silva Pais, G. (2011). Single minute exchange of die: a case study implementation. Journal of technology management & innovation, 6(1), 129-146.
- Dave, Y., & Sohani, N. (2012). Single Minute Exchange of Dies: Literature Review. International Journal of Lean Thinking, 3(2), 27-37.
- Ani, M. N. B. C., & Shafei, M. S. S. B. (2014). The effectiveness of the single minute exchange of die (SMED) technique for the productivity improvement. Applied mechanics and materials, 1144-1148.