Single-Minute Exchange of Die
SMEDSingle-Minute Exchange of Die (SMED) is a lean manufacturing method for reducing the time it takes to complete an equipment changeover.
Single-Minute Exchange of Die (SMED) is a system for reducing equipment changeover time to less than 10 minutes. The term 'single-minute' refers to a single-digit number of minutes. It aims to minimize downtime and allow for smaller production batch sizes. This increases production flexibility and reduces inventory levels.
The SMED process analyzes every step of a changeover. It categorizes tasks as either internal or external. Internal setup activities can only be performed when the machine is stopped. External setup activities can be completed while the machine is still running. For example, gathering tools and materials is an external activity. Unbolting a die is an internal activity.
The primary goal is to convert as many internal activities to external ones as possible. This means preparing everything needed for the changeover before the machine stops. Once activities are separated, the team works to streamline both internal and external tasks. This involves simplifying adjustments, using quick-release clamps instead of bolts, and standardizing procedures.
Implementing SMED on the shop floor improves machine availability and overall equipment effectiveness (OEE). It enables manufacturers to respond more quickly to customer orders. This is because smaller batches can be run economically. The result is lower work-in-progress (WIP) inventory and shorter lead times.
A metal stamping facility reduced its press die changeover time from 45 minutes to 7 minutes. The team began pre-staging the next die and tools next to the press while the current job was running. They also replaced manual bolts with hydraulic clamps, allowing the operator to secure the new die in seconds.
Does 'single-minute' in SMED mean the changeover must take only one minute?
No, it means reducing the changeover time to a single-digit number of minutes, so anything less than 10 minutes.
What is the difference between internal and external setup activities?
Internal setup activities can only be done when the machine is stopped. External setup activities can be completed while the machine is still in production.
Can SMED be applied to processes other than die changes?
Yes, the principles of SMED apply to any type of changeover or setup process in manufacturing, including printing, packaging, and assembly.
What are the main benefits of implementing SMED?
The main benefits are increased machine uptime, the ability to run smaller batch sizes economically, and greater production flexibility.
How do we start a SMED project?
Begin by forming a team to observe and record an entire changeover process. This analysis helps identify all the individual steps and separate them into internal and external activities.
Changeover Time
Changeover time is the total time it takes to switch a production line or machine from making one product to another.
Lean Manufacturing
Lean manufacturing is a production method focused on maximizing customer value by systematically eliminating waste from processes.
Just-In-Time
JITJust-In-Time is a production strategy where items are created or delivered only as they are needed, minimizing inventory.
Kaizen
Kaizen is a philosophy of making continuous, small improvements in processes and products, involving all employees.
Overall Equipment Effectiveness
OEEOverall Equipment Effectiveness (OEE) is a metric that measures manufacturing productivity by combining equipment availability, performance, and quality.