PRODUCTION SYSTEMS AND OPERATIONS MANAGEMENT

©1998 Joseph Martinich. All rights reserved. None of these materials can be stored, transmitted or reproduced by any means (electronic, mechanical, photocopying or otherwise) without the written permission of Joseph Martinich. These materials may be used by students in classes taught by Professor Martinich at University of Missouri - St. Louis.


Quick Set-ups (Single-Minute-Exchange-of-Dies - SMED)


[8(60 min.) + 100(1 min.)]/100 units = 5.80 min/unit

If we increase lot size to 10,000, the average time/cost is

[8(60 min) + 10000(1 min)]/10000 = 1.048 min/unit

This is an 82% reduction in per unit cost.


Then for a batch of 100 units the average time/cost is

[10 min. + 100(1 min.)]/100 units = 1.10 min/unit

If we increase lot size to 10,000, the average time/cost is

[10 min + 10000(1 min)]/10000 = 1.001 min/unit

Thus, the benefits from increasing lot sizes are small.




1. Observe and analyze in detail how the set-up is currently performed.

2. Eliminate any unnecessary tasks.

3. Of the activities currently performed, separate internal set-up activities from external set-up activities, and perform external activities while the process is operating.

4. Wherever possible convert internal set-up activities to external.

5. Simplify and streamline all activities.


1. Observe and Analyze the Existing Process


2. Evaluate Each Task and Try to Eliminate as Many as Possible


3. Separate Internal Set-up Activities from External Activities and Perform External Activities while the Process/Machine is Operating



4. Redesign Internal Set-up Activities to Convert Them to External Activities


5. Simplify and Streamline Activities

1. External set-ups time can be reduced through better tool and material storage and transport.

2. Dies and other parts that must be changed during set-ups should be standardized in size and shape.


3. Use the same standard components and fasteners for each set-up

4. Use fasteners that can be loosened and tightened with a single turn, rather than those that require turning the fastener several revolutions. Use fasteners and attachments that can be installed with a single tool.

5. Reduce or eliminate adjustments by using fixed settings and markings on dies, tables, and guide bars. Every set-up can be pre-marked so that tools and dies do not have to be measured each time; the "mark-points" on the dies and tools simply have to be matched with those on a table or guide bar.

6. Have two or more workers doing the internal set-up in parallel. For example, if adjustments have to be made by going back and forth between the front and back of a machine, the walking can be eliminated by having two workers do this.




URL: http://www.umsl.edu/~jmartini/pomnotes/websmed.htm
Page Owner: Joseph Martinich (Joseph.Martinich@umsl.edu)
Last Modified: February 5, 1999