1) Toyota Production
System
No older definition
New:
To gain a clearer view of 'ideal systems, it
is perhaps helpful to know more about Toyota. The "Toyota Production System-
used by Toyota to make cars has evolved over the last 50-plus years, inspiring
great admiration among competitors and academies. Several management
philosophies and catch phrases have been derived from practices at Toyota,
including "just in time" (JIT) manufacturing, 'lean production, and
"re-engineering-. Toyota uses several of these novel policies in concert as
described in Womack and Jones (1999). The prototypical Toyota system includes:
• "U-shaped cells,- which has workers follow
pails through many operations. This approach appears to build back some of the
"craft-accountability lost by the Ford mass-production methods. Performing
operations downstream. workers can gain knowledge of mistakes made in earlier
operations.
• "Mixed production" implies that different
types of products are made alternatively so that no batches greater than one are
involved. This results in huge numbers of "set-ups" for making different types
of units. I lowever. the practice forces the system to speed up the set-up times
and results in greatly reduced inventory and average cycle times (the time it
takes to turn raw materials into finished products). Therefore, it is often more
than possible to compensate for the added set-up costs by reducing costs of
carrying inventory and by increasing sales revenues through offering reduced
lead times (time between order and delivery).
• "Pull system" implies that production only
occurs on orders that have already been placed. No items are produced based on
projected sales. The pull system used in concert with the other elements of the
Toyota Production System appears to reduce the inventory in systems and reduce
the cycle times.
Theodore T. Allen, Introduction to
Engineering Statistics and Lean Sigma, pg.128
2. Ring Rolling (New)(Manufacturing type)
No old definition.
Ring rolling is a deformation process in which a thick-walled ring of smaller diameter is rolled into a thin-walled ring of larger diameter. The before and after views of the process are illustrated in Figure 19.7. As the thick-walled ring is compressed, the deformed material elongates, causing the diameter of the ring to be enlarged. Ring rolling is usually performed as a hot-working process for large rings and as a cold-working process for smaller rings.
Applications of ring rolling include ball and roller bearing races, steel tires for railroad wheels and rings for pipes, pressure vessels and rotating machinery. The ring walls are not limited to rectangular cross sections; the process permits rolling of more complex shapes . There are several advantages of ring rolling overaltemative methods of making the same parts ;raw material savings ideal grain orientation for the application, and strengthening through cold working.
(Mikell P. Groover, Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, page 403-404)
3. Gear Rolling (New)(Manufacturing type)
No old definition.
Gear rolling is a cold working process to produce certain gears. The automotive industry is an important user of these products. The setup in gear rolling is similar to thread rolling, except that the deformed features of the cylindirical blank or disk are oriented parallel to its axis (or at an angle in the case of helical gears) rather than spiraled as in thread rolling. Alternative production mehods for gears include several machining operations. Advantages of gear rolling compared to machining are similar to those of thread rolling: higher production rates, better strength and fatigue resistence and less material waste.
(Mikell P. Groover, Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, page 404)
2. Ring Rolling (New)(Manufacturing type)
No old definition.
Ring rolling is a deformation process in which a thick-walled ring of smaller diameter is rolled into a thin-walled ring of larger diameter. The before and after views of the process are illustrated in Figure 19.7. As the thick-walled ring is compressed, the deformed material elongates, causing the diameter of the ring to be enlarged. Ring rolling is usually performed as a hot-working process for large rings and as a cold-working process for smaller rings.
Applications of ring rolling include ball and roller bearing races, steel tires for railroad wheels and rings for pipes, pressure vessels and rotating machinery. The ring walls are not limited to rectangular cross sections; the process permits rolling of more complex shapes . There are several advantages of ring rolling overaltemative methods of making the same parts ;raw material savings ideal grain orientation for the application, and strengthening through cold working.
3. Gear Rolling (New)(Manufacturing type)
No old definition.
Gear rolling is a cold working process to produce certain gears. The automotive industry is an important user of these products. The setup in gear rolling is similar to thread rolling, except that the deformed features of the cylindirical blank or disk are oriented parallel to its axis (or at an angle in the case of helical gears) rather than spiraled as in thread rolling. Alternative production mehods for gears include several machining operations. Advantages of gear rolling compared to machining are similar to those of thread rolling: higher production rates, better strength and fatigue resistence and less material waste.
(Mikell P. Groover, Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, page 404)
4. Assembly-Oriented Product Design (New) (Assembly)
No old definition
Assembly-oriented design is a requirement designers are faced with very often;it is intended mainly to save costs and production times as well as to assure quality in the production sector of assembly. So far little help for assembly-oriented design has been offered to designers. Such help included relatively trivial rules, such as ''reduce the number of components'' or ''provide uniform joining directions'' or comparisons between assembly-oriented and non-assembly-oriented solutions in the form catalogues. As for the normally global rules, it must be stated that they may lead to wrong solutions in concrete applications; for example, it is quite conceivable that a multitude of simple components is more economical to assemble in a suitable automatic machine than a few complex components for which automation is not possible. It may be assumed that when, for example, a multi-axis industrial robot is used as an assembly means, uniform directions of assembly are of minor significance. Comparisons in catalogue of solutions must be regarded with the same reservation, because the assembly means is not considered, i.e., the type of assembly. A product that has an ''assembly -oriented'' design in the beginning may lead to the most uneconomical overall solution in assembly system that is not tailor-made for the product.
(Gideon Halevi, All-Embracing Manufacturing, page 139-140)
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