19 November 2016
Industrial engineers have to improve the machine utilization economy. To do that we need principles of machine utilization economy, like principles of motion economy.
What principles can be proposed?
1. If it is a machine tool, we have to investigate cutting tools, coolants, cutting speeds, feeds, depth of cut and jig and fixtures to improve the utilization and productivity. Taylor himself did all these evaluations and suggested many improvements, which are still valid today.
2. For all machines, finding the load at which maximum efficiency is obtained is done. The load planning has to take into account the maximum efficiency load.
3. Six sigma provides a way to optimize the working of any machine. The factors that affect the working of the machine are to be identified, and the levels at which they can be operated are to be found. Then the combination of factors and levels at which the best output will come will be obtained and machine can be run at that combination or setting.
4. Calculate economic batches for various components to be made on the batch and use those batch quantities. JIT as an idea is welcome, but you can use it only when you implement SMED and drive down the setup time.
5. Look for opportunities to implement Pokayoke features on the machine so that defects are reduced to very low levels (zero defects).
6. Use the developments in maintenance management to have the most efficient and productive maintenance system.
Total Productivity Equipment Usage Management
Six major categories of inefficiencies and losses related to equipment - machines
affect the overall performance of the equipment namely:
1. Equipment failures/breakdown losses are the time losses and quantity losses caused by defective
2. Set-up and adjustment losses are defined as time losses resulting from downtime and defective
products that occur when production of one item ends and the equipment is adjusted to meet the
requirements of another item.
3. Idling and minor stop losses occur when the production is interrupted by a temporary malfunction
or when a machine is idling.
4. Reduced speed losses refer to the difference between equipment design speed and actual operating speed.
5. Reduced yield losses occur during the early stages of production from machine start up to stabilization.
6. Quality defects and reworks are losses in quality caused by malfunctioning of production equipment.
Selection Principles on Manufacturing System for Part Family
Li Tang1, Derek Yip-Hoi2, , Wencai Wang1, Yoram Koren1
1 NSF Engineering Research Center for RMS, University of Michigan, Ann Arbor, U.S.A.
2 Mechanical Engineering Dept., University of British Columbia, Vancouver, Canada