Advances in numerous manufacturing technologies, including CNC equipment, tooling materials and configurations, automation, controls, and information processing make the task of justifying machine tool investment vital to ensuring a successful manufacturing operation. Surviving and even thriving is still possible for metalworking operations of all sizes given the right blend of technology, equipment, and people.
The rate of change in the world over the last 10 years has been nothing short of phenomenal. In fact, it's a persuasive argument that the world has changed more in the last 10 years than in the previous 50. Exemplified largely by changes in the automotive industry, the last 10 years saw an almost total reworking of traditional manufacturing practices in North America. Ideas such as just-in-time, pull production, and numerous variations on the theme of lean manufacturing were put in place in response to ever-escalating competitive and cost pressures. As such concepts began to become reality in American manufacturing, productivity and quality rose. And as quality and productivity rose, so did the demand for further gains.
Many related issues influence this scenario. CNC equipment is much more productive than it was even 10 years ago. Computing power, with order-of-magnitude increases in processing speed and memory capacity along with significant reductions in cost, makes electronic communication and data crunching an integral part of our lives. It's also a fact that fewer qualified people are choosing manufacturing as a career, which forces closer examination of automation and other means of accomplishing more with less. And product lot sizes and life cycles continue to shrink as consumer influence over product choices and options grows stronger.
Traditional formulae for justifying machine tool purchases are out the window in such times of accelerating change. The lowest purchase price or the most powerful and costly features by themselves will not result in manufacturing dominance, much less a manufacturing company's success. To survive, buyers of manufacturing technology have no choice but to buy smarter.
With the emergence of China as the world leader in consumption of CNC machine tools, OEMs worldwide have proven that the entire globe is their production base. Searching for the lowest-possible price is becoming easier and easier. It cannot be stated more simply, or often enough, that for any manufacturing organization to survive, it must be able to deliver three things: the highest quality, the greatest production throughput, and the lowest cost.
Meanwhile, conditions have changed after a prolonged period of machine tool sales stagnation. During the slowdown, substantial manufacturing capacity either left the US or stopped manufacturing entirely. Large OEMs in the automotive, industrial equipment, aerospace, and other industries continue to slash their supplier bases to obtain the best possible pricing.
Some would argue this makes the current momentum to buy a response to capacity issues more than productivity issues. I would argue that the two are of equal importance.
While the current situation may have caused some capacity shortages, it is doubtful that manufacturers can realize their full profit opportunities without increasing productivity. To maintain a competitive advantage, it's imperative to realize the benefits available from productivity improvement. These may come from faster metalcutting; simpler, more powerful and robust programming; decreased setup time; improved options for automation; and the ability to take advantage of advances in information and communications technologies.
Every resource fo
r obtaining productivity needs to be closely examined. Today there are wide-ranging opportunities with machines that improve productivity, but beyond that there are even further opportunities for combining operations into a single process for even more substantial savings.
Where metalcutting is concerned, efficiency gains with modern CNC equipment are substantial compared to as little as 10 years ago. For VMCs, we recently compiled data on metal-removal rates on a variety of materials and other productivity measures. They showed our Nexus VMCs are up to four times more productive than previous Mazak models, compared with a 1991 baseline, with no increase in inflation-adjusted price.
Most manufacturers want to be more efficient, and have a plan for becoming so. Traditional modes of justifying capital equipment purchases often include regularly scheduled upgrades of cutting capacity, motor size, spindle speeds, and new tooling materials and configurations (when such opportunities present themselves). Manufacturers then devote significant time and effort to supporting all the advances possible from a new piece of equipment, when the real opportunity is to consider the possibilities of process change. It's the difference between thinking "How can I cut this part faster?" versus "Is there a way to cut it that might eliminate multiple setups and multiple machines? What advantages would that change bring to my company?"
History is part of the problem. Single-setup, simultaneous five-axis machining, for example, is not new. Such equipment first saw use in the early 1950s in the defense industry. The parts produced might require days or even weeks of machining on a large scale. Machines were expensive, and programming them required highly trained specialists using custom programs.
These limitations inhibited the expansion of five-axis machining in the commercial sector, where parts could be machined on three-axis machines supported by a wide variety of CAD/CAM systems. In general, saving time or setups with five-axis machining didn't offset the costs associated with obtaining the knowledge required to program and use them effectively.
Now, machine-tool manufacturers, tooling suppliers, CAM software providers, and the entire manufacturing supply chain face the same global competition. The result is an intense, ongoing mission to deliver more technology across the board to broader segments of the market. Consider also that, at the same time, products are becoming more complex and product life cycles are shorter. Complex surface machining isn't just for aerospace structures, but for molds for detergent bottles. And when customers say they need a new mold tomorrow, they really mean it. Business is won or lost based on speed of delivery as well as quality of product.
People are another consideration. Button-pushers are easily obtained anywhere in the world, but empowered employees contribute process knowledge with each new job. Process knowledge, or the combination of ability, training, and experience, is not so easy to achieve. The challenge, therefore, becomes making single-setup, multitasking accessible and productive for manufacturing organizations of all sizes.
Educating customers is never easy, but consider the advantage of a process change involving machining with multitasking equipment. Production that might normally require months to complete can be reduced to days. For moldmaking, a multitasking machine could produce both cavity and core from the same block of material in a single setup. Cooling holes and grooves could be machined on the side and back faces of both cavity and core, and a tilting spindle allows face milling from any angle.
The number of machines required is reduced from three (two VMCs and a vertical with a rotary table) to one, with a corresponding reduction in the number of operators. Setups are reduced from 16 to one, number of programs needed from 16 to one, and in-process time is cut from 32 days to two. For deep-cavity applications like injection molds, stamping dies, or even porting engine blocks, cavities can be machined and finished to a degree where there is no need to cut electrodes for EDM processing. Bottom-line, there's a lot more creativity that's available to produce a complex part in less time.
Beyond the field of moldmaking, possibilities exist today for an electrical generator component that would normally require an NC lathe, VMC, HMC, and vertical with special features to be produced on a single multitasking machine in a single setup. Besides the change in production throughput from 47 hr to less than 7 hr, consider the benefits this change brings to numerous aspects of a manufacturing operation:
- Profit. Cash flow considerably improves.
- Lower direct expenses. Machines are reduced from four to one, fixtures from six to one.
- Lower overhead. Operators and attendant benefits are reduced from four to one.
- Part quality. Going from six setups to one greatly reduces accumulated precision error.
- Lower indirect expenses. Having a single machine uses floor space more effectively, environmental impact is reduced, and movement of material through the plant is made more efficient.
Making process change a reality should be the singular mission of our time for manufacturing technology providers. Real-world examples are emerging, and should be broadly disseminated to prove this is not theory but an emerging reality. Efficiency leaps of hundreds or thousands of percentage points change our mindset of keeping up with the competition to establishing a new manufacturing benchmark.
This article was first published in the December 2004 edition of Manufacturing Engineering magazine.