What is SMED and its Importance?
What is SMED and Why is it Important?
LEAN principles are all centered on process improvement which leads ultimately to improved efficiency which leads to higher profitability. The concept is simple but getting there is usually harder that one can imagine.
One of the vast building blocks of LEAN relates to quick changeover setup. The faster the changeover times, the less downtime of equipment. Remember DOWNTIME is the definition of the Eight Deadly Waste of a manufacturing environment.
The key to quick changeover setup is the term SMED. SMED stands for Single-Minute Exchange of Die. The SMED system is a theory and set of techniques that make it possible to perform equipment setup and changeover operations in fewer than 10 minutes – in other words, in the single-minute range. SMED principles can be used and applied in almost any operation or process. It was developed to improve die and machine tool setups.
SMED’s goal is to reduce the setup time to within minutes. Depending on the process, setup within minutes may be very difficult, but in most cases, if the SMED principles are followed, drastic reductions in setup time can be obtained.
The basic principles of SMED are:
- Identify internal versus external changeover tasks.
- Analyze each task’s real purpose and function.
- Focus on no/low cost solutions.
- Aim to eliminate changeover time.
So you ask, how do I go about this process? SMED is typically broken down into three stages. Each stage has specific tasks and objectives and all are inter-related and work together. Those stages are outlined below.
Stage 1 – Separate internal and external setup
Certain tasks can clearly be done before machines are stopped for changeover. These include lining up the right people, preparing parts and tools, making repairs, and bringing the parts and tools closer to the equipment. There are three practical techniques to doing this:
- Develop and implement changeover checklists.
- Perform function checks on parts and tools.
- Reduce transportation or tools, parts, and materials.
By separating these tasks and performing them as external setup can cut changeover time by as much as 30% to 50%.
Stage 2 – Convert internal setup to external setup
Stage 1 functions alone will not reduce internal setup time to within the single minute range. For that you must implement Stage 2. There are two primary steps to Stage 2:
- Look at the true functions and purposes of each operation in your current internal setup
- Find ways to convert these internal setups to external setup.
The key to successful implementation of Stage 2 is to look at the function as if you are new to it. Three practical techniques help shift internal setup tasks to external setup. Those techniques are:
- Prepare operating conditions in advance
- Standardize functions
- Use intermediary jigs
Stage 3 – Streamline internal and external elements
In this third and final stage, all of the remaining internal and external setup operations are improved. This can be done by looking closely at each operations function and purpose one more time. More specifically, Stage 3 improvements can be divided into external and internal setup improvements. Four basic approaches to accomplishing this are through:
- Maintain a visual organized workplace
- Implement parallel operations
- Eliminate the need for adjustments
- Use functional clamps
- Mechanize functions
SMED provides many benefits for companies and those working within the company. More specifically, the advantages of SMED along with quicker and more efficient setup times are improved flexibility, quicker delivery, better quality and higher productivity. Through these benefits you will also see simpler setups and safer changeovers, less inventory and more standardized processes.