The early enthusiasm for multi-tasking machine tools is finding growing rationale far beyond the obvious attraction of "done on one."
That versatility factor will continue to draw -- after all, who can resist considering a multi-tasking contender where four such units have been known to replace as many as 20 conventional machines, asks Brian Papke, president of Florence, Ky.-based Mazak Corp., the U.S. operations of Japan's Yamazaki Mazak Corp. (Papke can't -- he attributes the performance of his manufacturing operations, no surprise, to the use of Mazak multi-tasking equipment.)
In addition to reducing costs by enabling one machine to do the work of several, multi-tasking is motivating the rethinking of factory layout and operations, product design and machine tool features in general, adds Papke. "For example, one result is a new emphasis on machine intelligence." (See "Reaching For A Smarter Factory.")
In multi-tasking, fewer machines are needed and that means fewer tools, operators and all of the means necessary to move parts between machines. The parts produced are inherently more accurate as one set of fixtures and one machine tool reduce the errors and tolerance stackup due to multiple setups.
Papke says that at the user level, the process simplification made possible by multi-tasking offers an opportunity to improve both product characteristics and assembly by designing fewer, albeit more complex parts. With multi-tasking machines, part complexity doesn't carry the cost penalty of the conventional manufacturing approach, explains Papke.
The Case For Multi-tasking
Why do manufacturers opt for multi-tasking machine tools? Here are some of the reasons why:
Reduces direct cost -- fewer machines, fixtures and tools, and far less labor.
Slashes non-value-added time, multiple setups, part handling and queue time.
Compresses lead-time -- from days or weeks to hours.
Improves cash flow -- smaller, frequent shipments on customer demand.
Reduces work-in-process (WIP) inventories -- releasing cash for operating/investment.
Improves part accuracy -- no tolerance build-up from multiple setups.
Reduces indirect costs -- less floor space, utilities and maintenance.
Reduces lot sizes with no cost penalty -- lots of one or assembly kits.
Runs "lights out" with automation -- more cutting time with no added labor.
Improves customer satisfaction.
Improves competitiveness through new customers and markets.
Time savings can be significant with multi-tasking. Overall cycle time is reduced as a result of eliminating the non-value-added activities of multiple setups, locating tools and moving parts to machines. For example, one multi-tasking machine could substitute for a sequence of processing on a combination of vertical turning lathes, horizontal machining centers, vertical machining centers and in some cases radial arm drill presses, says Papke. Setting up the part in each machine not only takes significant amounts of time, it introduces variations that must be corrected and compensated for.
Controlling part manufacturing in one machine with a single set of fixtures can greatly reduce the possibility of rework and scrap while holding tighter tolerances.
Multi-tasking machines also reduce work-in-process, the pile of parts that accumulate between operations on the factory floor, adds Papke. Since small lot sizes become more practical, the temptation to produce just-in-case inventory is minimized.
With that enhanced capability, Papke predicts smaller plant floors and a new significance for the "right" operator training. Ironically, he also notes that overall, fewer machines will be sold. He also expects that multi-tasking, now a machine category, will spread to becoming a characteristic or features of virtually all machine tools.