SMED……. Meaning
also known as
- Changeover Time Reduction
- Set-up Time Reduction
SMED…Change over time Definition
Change over time :-
Time interval between the last “good” part
produced before the changeover begins and the first
“good” part produced afterwards.
( Includes part approval time )
SMED… Benefits
• Increased Time Available for Production
• Smaller Batch Sizes
• Facilitates Sequential Production
• Increased flexibility of Production
• Reduced Inventory
• Reduced Scrap and Repair
• Reduced Number of Containers
• Reduced Size of Containers
SMED… Steps
There are simple steps to follow:-
1. Video shoot the entire set-up without prior information
2. List down all activities in the Record sheet from the
video in presence of operator
3. Separate out Internal , External Set-up activities and
waste
4. Think for simple ways to reduce / eliminate internal
activities OR to convert it to external activities .
( Implement Kaizens ... Simplify fittings and tightening )
5. Parallel activity is the best way to reduce set-up time.
SMED… Internal to external
Following are the examples to convert Internal to
External set-up activities
1. Determine which elements can be performed while machine
is running (External) and which cannot be done unless the
machine is down (Internal)
2. Focus on the function/purpose of each element
3. Analyze the setup
Question everything
Discuss with the operator every aspect of the changeover
Document new ideas on the process improvement chart
Use QC tools for evaluation and improvement ( graphs )
4.Develop checklist, parts and steps required in an operation
-Names
-Specifications
-Number of blades, dies
-Pressure, temperature and other settings
-Numeric values for measurements and dimensions
-Improve transport of dies and material
5. Advance preparation
6. Function standardization
7. Use intermediary jigs
8. Avoid
- Transport of finished goods to storage or raw
materials to the operation while the machine is down
- Jigs, tools and dies are delivered to the machine after
it has been shut down
- Discovery of defective tools, fixtures, bolts
- Searching for bolts, blocks etc. after the machine
has stopped running
SMED… Internal Improvement
1. Parallel operations - improve staffing if needed
2. Functional clamping
Eliminate bolting
3. Elimination of adjustments
Positive stops
Intermediate jigs/fixtures
4. Improve ergonomics of setup
Improve method of putting dies/tooling in machine
(die extensions, die carts /trolleys, moving bolsters )
Before After
Manual
Un Clamping Tools Unclamping From
By Using Hand Tools Hydraulic Clamps
SMED… Hints for Internal Improvement
1. Minimize " turning " movements they require
several grasp-release motions
2. Fit at once, in a single motion
3. Use blocks, jigs, templates
4. Standardize tools, types and sizes of screws, nuts
5. Avoid using multiple sizes of screws / spanners
6. Adjustments:
- Fix standard values
- Find out adjustment-less methods through
physical means, like stoppers, butting blocks...
- Get custom made tools if necessary
- Color coding for valve / knobs setting
- Sub-routine ( Part program ) selections in CNC
machines
- Quick Limit settings ( Common dog rails )
- Quick connectors for electrical and PLC
7. Specific examples :-
- Moulds actually preheated on and by the machine
itself will be preheated in advance in a small
additional oven.
- Products are mixed by the machine, requesting
trials and adjustments, will be mixed outside and
fed to the machine ready for use
- Prepare sub-assemblies in advance
- Keep trial / input component ready
8. Examples of fastening
- Simplification of fittings and tightening
- On every screw, regardless to length, it is always the
last turn which tightens, conversely the first who
releases
...Meaning a possible tightening with a single turn
is as efficient as screwing 10 turns, but so much
faster
( Also true for nuts )
8. Examples of fastening ( Contd… )
- There are tightening solutions without screws and
bolts, because even if screwing turns are reduced,
they keep looking like each other, but of another
size, and fall into the worst possible place!
- Use
- U shape washer
- quarter turn screws
- U shape grooves, magnets, plugs ,cam and
lever tights
“ The need for tools can be eliminated ”
9. Work together :
- Assign defined responsibility in multiple tasking
and sequencing
- Work in parallel instead of in sequence
SMED… Generate New Ideas
Question Followed by Action Expected
What is the purpose? 5 Why's Eliminate Unnecessary
activity
Where is this being done? 5 Why's Combine or change place
When is this being done? 5 Why's Combine or change time or
sequence
Who is doing this? 5 Why's Combine or change
How is this being done? 5 Why's Simplify of improve method
SMED… Benchmarks
1. Single touch set-up :- Press one button and next
fixture / die is indexed automatically
2. Zero Touch Set-up :- After finishing of first part ,
next tooling , fixtures / dies indexed automatically.
3. Maximum permissible Set-time should be less
than or equivalent to cycle time of one piece
SMED
1. All set-ups in single digit
( maximum 9 minutes )
2. Set-up change to be performed not as per
organizational convenience but as per
Customer plan
3. Ensure all SAFETY procedures are
adhered.
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