Industrial Machine Trader

Technology Shapes Shop Ambitions

Thu, 09 Sep 2010 10:12:14 -0500

Horizontal machining put Proteus Manufacturing on the fast track to growth. John Tamulynas III (left), president, and Bill Burris, general manager, examine a part machined on a Kiwa KH-45 HMC. Technology advances in machining centers�horizontal, vertical, and universal�have been coming fast and furious. Controls, cutting tools, and automating equipment have extended the reach of machining centers whether for one-off contract manufacturers or for production-oriented OEMs. Transitioning from the not-so-hot industry to the hot industry (and back again, if necessary) requires technology designed to meet the challenge. And those challenges may be posed by applications as diverse as aerospace, medical, energy, or even automotive. They come in the form of larger and larger workpieces made from the toughest materials, or the smallest, thinnest, and most delicate parts. Technical innovation can mean everything when assessing a machine's ability to meet the task at hand. In its growth path from prototype shop to precision manufacturer, Proteus Manufacturing (Woburn, MA) sought and obtained the precision aluminum machining capability required for optical and defense components like housings for cameras, lenses, and assemblies. As volume requirements and demand for the kind of precision that requires extensive testing, inspection, and control increased, the company found itself at a crossroads. John Tamulynas III, president, explains: "We discussed our situation with our machine tool supplier, Methods Machine Tools Inc. [Sudbury, MA], who recommended that we transition from multiple VMCs to an automated HMC." Proteus purchased a Kiwa KH-45 six-APC HMC. Working with the HMC quickly dispelled any concerns he might have had about the virtues of horizontal vs. vertical machining centers. As it turns out, Proteus was very pleased with the horizontal leap, primarily because of how the Kiwa H-45 reduced cycle time, moved the company into lights-out automation, and freed up more spindle time for other, previously strained operations. General Manager Bill Burris explains: "In the first two roughing ops, on one of our main machined components made of aluminum, the Kiwa reduced the cycle time by over 30%, and the pallet system has allowed us to go from one part to four parts at a time and run lights out. By putting our four to five jobs in one machine, we have opened up other spindles on other machines, creating more overall versatility and increasing productivity throughout our operation." The KH-45 offers in-the-field expandable tool and pallet technology, including the ability to expand from a two-pallet machine with 120 tools to a six or eight-pallet machine with 220 tools. It features a 400-mm pallet, and travel and work envelope of 29.5 diam x 39.4" (750 x 1000 mm), and can handle a table load of 1100 lb (500 kg). Machining center strategies are traveling along two distinct machining routes: robust heavy-duty machining of tough materials, and increasing size of machines for aerospace, power generation, and energy jobs, among other applications, according to Scott Walker, president, Mitsui Seiki USA Inc. (Franklin Lakes, NJ). "The tendency in machining center design is to have stiffer, more resilient machine frames, higher-torque spindles, and stronger drives to push tools through tougher materials. At the same time, five-axis trunnion-style machines are getting bigger and bigger, with up to 2.5-m clearance on the trunnion. What has happened is that aerospace manufacturers are putting larger pallets on the five-axis machines to accommodate longer or larger workpieces, or to be able to fixture a complete ship set. To build helicopter rotor hub assemblies, nose and window assemblies, engine assemblies, or landing gears, they would like to put all the pieces up for machining at the same time, machine them, and ship them as a completed set ready for assembly," Walker observes. To satisfy new aircraft and power-generation production requirements, Mitsui Seiki has released several four and five-axis machining centers. The new four and five-axis HMCs are designed for aerospace and energy applications, including airframe components, propulsion systems, landing-gear assemblies, wind-turbine gear boxes, and gas-turbine power-generation systems. Five-axis HMCs can handle a work diameter capacity of 2500-mm, 3-t work/fixture weight capacity, and a variety of increased axis-stroke options, and feature larger pallets than previous models and high-torque spindles (2700 N�m continuous). Capacity improvements for four-axis HMCs include new quill-type spindles for deep-boring operations, 5 and 10-t work/fixture weight capacity, up to 3-m axis stroke, high-torque spindles (2700 N�m continuous), and�like the five-axis models�tuned structure for heavy cutting in hard metals, large-capacity FMS systems, and the Fanuc 30i CNC. For robust five-axis machining, Heller Machine Tools (Troy, MI) has introduced its F series five-axis HMCs with HSK 63 or 40-spindle taper and three different workhead configurations. "The machines combine a high-torque spindle with five-axis machining capability, well-suited for medical, aerospace, and mold and die industries, and for machining complex, difficult-to-machine parts in a single setup," explains Heller's Tracy Ellis. The reason for the three different high-performance spindles is the need to machine smaller, lighter parts, frequently from tough materials such as titanium, or aluminum parts that benefit from high-speed machining. Two types of F-series machines are available; the FP and the FT versions. The FP 2000 and FP 4000 models are five-axis machining centers with a pallet changer intended for complex shapes or five-sided machining in production houses. The FT 2000 and FT 4000 models feature fixed tables for high cutting capacity and the best possible surface finish. Use of a C head or tilting head provides the fifth-axis capability. The FT 2000 and FP 2000 models have X, Y, Z strokes of 630 x 630 x 830 mm; the FT 4000 and FP 4000 have X, Y, Z strokes of 800 x 800 x 1000 mm. Spindle technology is at the core of the new F-machine series. Three different designs are available on all models: the PCU 63 high-torque universal head; the SCU 63 speedcutting universal head, and the SCT 63 speed-cutting tilt spindle for high-speed cutting. The two swivel-head units are well-suited for complete machining of contoured surfaces of any kind, such as five-axis simultaneous machining of aerospace and medical applications. Ellis explains: "Heller engineers determined that the most flexible, robust, and efficient way to do five-face and five-axis machining is to have one of the axes in the workhead. Using a B-axis table in combination with a universal or tilting workhead allows greater table loads, larger working envelopes, greater accessibility than five-axis machines that have two axes of motion under the workpiece, such as a tilt/rotary table or C-over-B type." The new F-series machines are compatible with all Heller automation including pallet pools, pallet magazines, and robotic solutions. Handtmann CNC Technologies Inc. (East Dundee, IL) is well known for building gantry-style machining centers for large workpieces. For smaller workpieces, Handtmann has designed and introduced the five-axis HBZ Compact-Cell HMC for machining workpieces in the 2 x 1-m size segment. For workpieces starting from 4 x 2-m size, the company had already gained the benefits of HMC design, i.e. high material removal rates and efficient removal of chips and coolant, in designing its HBZ AeroCell. The HBZ CompactCell is intended for applications in general metal machining, the automotive, aerospace, mold and die, and solar industry, and for machining materials from plastics, to aluminum, to steel, whether in a three-axis or five-axis mode. The machine uses high-frequency spindles rated to 75 kW, and spindle speeds to 30,000 rpm, as well as high travel speeds and accelerations to achieve high metal-removal rates in a compact footprint. Loading/unloading in the horizontal position is easily done in front of the machine. The machine is accessible from all sides, and automated loading can be accomplished with crane, rail, or pallet-storage systems with a handling portal. Highly regarded for its transfer line and flexible-machining technology, Grob Systems Inc. (Bluffton, OH) has expanded the capability of its universal G 350 five-axis stand-alone HMC to accommodate thin, cylindrical workpieces. Key design innovation in this machine is a rotary table with a part support that enables production of workpieces for tool, turbine (aircraft), and medical device manufacturers. Specific applications require boring bars with complexly arranged inserts for seats and turbine blades. The five-axis machine works for both applications with its two rotating axes both in the table of the G 350. Blade machining, however, requires a high level of dynamics due to the abrupt reversing points at the blade transition from one 3-D surface to the other. "A large tabletop would be problematic for small, thin, and complex workpieces, which need their entire surface to be machined," explains Bob Ruelle, account manager who is responsible for Grob's standard machining centers. "Longer tools with a greater projection would be necessary, and the risk of collision would be increased. We developed the small table and noticed that it is useful for more than just machining cutting tools and turbine blades. It can be used for parts for optical electronics, medical technology, tools, and molds used to produce electrodes." To clamp thin, cylindrical parts vertically, a lot of space is required. "We built a table option for workpieces with a diameter of only 250 mm. In contrast, the standard table measures 570 mm. The small table has a rigid backbone for the 375-mm distance between the table surface and the tip of the support for clamping both sides. To radially clamp and hold the workpiece, instead of using fixtures corresponding to the workpiece, normally a three-jaw chuck can be designed for the rotary table." Up to four hydraulic couplings are provided on the table for hydraulic clamping and unclamping, either through manually adjustable valves, or, optionally, through proportional valves controlled by the CNC. The stroke required to clamp different parts is adjusted by a hydraulic flow meter (at 120 bar/1740 bar) for ease and safety. Loading options for the G 350 HMC include robots, linear portal, rotary part changer, and manual loading. MAG Americas (Cincinnati) continues to spread eagle the high-end, large-part segment of the aerospace machining market with its five-axis profilers and its newly introduced modular HMCs for pump, valve, off-road, and other components. The HyperMach H4000 five-axis horizontal profilers are slated to produce aluminum airframes and bulkheads for the F-35 Joint Strike Fighter (JSF) and the CH-47 Chinook helicopter in a two-machine cell for Pacific Contours at its Spring Valley, CA, facility. This represents the second acquisition of MAG's high-velocity platform for tight-tolerance machining on multiple surfaces. The first was a six-machine H4000 cell for Brek Manufacturing (Gardena, CA) for precision machining of complex structures for defense and commercial aircraft programs. The H4000 is a high-speed, high-power five-axis contouring machine with full portal construction, a fully enclosed cutting zone, and material handling for precision machining of large aluminum plate and forgings. The two-machine, multipallet cell will use MAG's Cincron cell controller and automation for untended 24-hr operation. Modularity in machine construction is providing MAG HMCs with a variety of configurations. The modular Specht 500/630 HMC sports "green design" that, among others things, allows it to sleep when idle, eliminates warm-up time, requires half the coolant and one-third the air extraction needs of previous designs, enables the machine to cut dry, wet, or MQL, and be compact�just 1.8-m wide. Modular configurations include linear-motor or ballscrew drives, CAT 40 through HSK-100 tool interfaces, six spindle options, four control options, and three five-axis configurations tailored to requirements from one-off work in job shops to agile machining lines. Control options include Fanuc 32i and 31i, Siemens 840D, or Bosch Rexroth MTX, and software options include MAG's Freedom eLog web-based production management system, Freedom eView, and Omative Adaptive Control. For high-precision machining of components for large aerospace, power-generation, pump, valve, and off-road equipment, MAG has expanded the head options for its HMC 1250/1600 by adding a new 180,000-position Aaxis tilt spindle for five-axis horizontal machining. The 6000-rpm, 46-kW tilt spindle joins the 10,000-rpm, 56-kW spindle, high-speed 24,000-rpm spindle; the high-torque 2600 N�m spindle; and two live spindles as headstock options. The high-torque 80-kW spindle is well-suited for aerospace titanium cutting. The live spindles extend W-axis reach by up to 800 mm, enabling deep-cavity milling to high precision with shorter, more rigid tools. One of a select few machine-tool builders that still designs and manufactures its own CNC control, Milltronics CNC Machines (Waconia, MN) is readying its next generation all-digital control, the 8200, for introduction at IMTS. According to James Broz, director of new product development, the 8200 is a real-time, RT Linux-based, all-digital control with faster, quicker, and better number crunching capabilities, especially applied to multiaxis machining, including five-axis or mill-turn machining. Milltronics' Twin Table machining centers feature a rigid bridge-type platform with the capability of being configured as two 22 x 26" (559 x 660-mm) tables or one table measuring 44 x 26" (1118 x 660 mm). The TT series of machines are available with 24, 40, 60, and 80" (610, 1016, 1524, 2032-mm) Y-axis travels. "The TT machines are targeted to expand Milltronics' market position," says Broz. "Being bridge-style machines, they exhibit more rigidity than typical pallet-changing machines." The company's HM family of machining centers features four-sided machining with a rotary table or can handle large mold machining. A new small-travel VMC, the VM2016, will be introduced at IMTS, and showcased along with the 8200 control. B.K. Tool Co. Inc. (Fairfield, OH) depends upon drilling, tapping, and milling operations provided by Feeler vertical machines for components made from materials ranging from aluminum to stainless. Destined for use in products such as printing presses, conveyors, or other assemblies, the components require consistently accurate machining. Mike Reed, machinist and part owner, credits the Feeler machines with being "stronger and heavier than other machine tools in our shop, resulting in less vibration during machining, so they make better cuts and are reliable." In error situations, for example a blown fuse, the Feeler machines automatically shut down, preventing potentially costly repairs. "This is in contrast to some of the other machines on our shop floor that have required expensive servicing or tool changer repairs," says Reed. "Of course, dependability doesn't end at the machine. Service and support are important factors as well," Reed notes. Feeler machines are supported by engineering and service from Methods Machine Tools Inc. (Sudbury, MA). For more information go to: http://www.sme.org/cgi-bin/find-articles.pl?&ME10ART26&ME&20100701&&SME&#article

Making a Difference!

Thu, 29 Jul 2010 13:51:00 -0500

As we read a lot in the news today about the Oil Spill in the Gulf, the economy being such a mess, the war in the Middle East, and all the other negative things they like to talk about all the time, it is hard to find anything good in the news. This being said, it also makes it hard to find much to be positive about in our daily lives. I have preferred to only catch the news on a rare occasion and mostly to see what the weather is doing and to read the paper only for the local information. Now, you might say I am trying to bury my head in the sand and hide from the reality of the world. That is not so. I am trying to keep a positive outlook on what is going on around us. I know the oil spill is costly and there are so many things it affects. I also know the economy is still in a turmoil, the war is far from over, and the entire country is mad at someone but they are not sure who. We all know someone in our lives that truly has done something good and decent and maybe even heroic that stands out in our lives or community. These are the people we need to be listening to and wanting to live like. The journalist get paid to write and present the drama of the news and for the most part, most of those people would much rather do a story on the young man that just saved 3 children from drowning in a river, or a babysitter who helped a child who was struck by a car. They also are sometimes portrayed as people who have no compassion or feeling for what they write or report. But, believe me, some of them care more than you can imagine. My point to all of this is, that to be a truly good honest person, we must give everyone in our lives a chance. Think before we speak or just to conclusions about what we are hearing right or wrong. This country needs to have people pulling together and not apart and it all starts with small groups and communities pulling together to make our own world a better place to live. Enjoy your life and help someone else enjoy theirs.

What Makes a Coolant Green?

Thu, 22 Jul 2010 10:39:16 -0500

Metalcutting fluids are ubiquitous in machining, and almost every manufacturing professional has seen advertisements for "green" metalcutting fluids. Suppliers to manufacturers insist that environmentally responsible coolants and lubricants can function just as well as conventional products, without requiring extensive modification of the equipment now operating on your shop floor. But just what is a "green" coolant? Brian Mattes, global senior research and development chemist at Master Chemical Corp. (Perrysburg, OH) responds that "green" has many meanings. "While metalworking typically focuses on certain raw materials to determine if a product is greener than another fluid, at Master Chemical," says Mattes, "we concentrate on three higher-level concerns: safety, environmental impact, and commercial sustainability. "The balance of these three concerns has always been at the heart of what is green, and they are interrelated. Minimizing waste in a process saves money and puts less byproduct into the environment. We advance the use of renewable resources in our products, but we also integrate green chemical management into our products and services. Longevity in the sump has a positive impact on the greenness of the entire manufacturing process, and therefore the greenness of the metalworking fluid." Suppliers offer green neat oils, synthetics, semisynthetics, and vegetable-based fluids. The performance of green fluids, such as Master Chemical's Trim E850 vegetable-based premium emulsion coolant, is comparable to the performance of conventional fluids, and they work well in a range of applications. However, the company believes that conventional premium metalworking fluids, like Trim E906 premium, low-foaming emulsion are often the "greenest" fluids, because they not only perform well, but can be maintained for longer periods of time. "Greener raw materials such as vegetable oils often deliver better lubricity," says Mattes. "But on a one-to-one ingredient comparison, vegetable oils are more prone to sump-life issues than conventional lubricants." Vegetable-based raw materials present concerns about availability, volatility, and seasonality of supply. There can be oxidation instability, biological issues, and societal concerns about genetically modified vegetable sources. Beyond these specific limitations, the chemistry of the fluid is significantly changed during the metal-removal process, according to Mattes. "What may have started out as a greener chemistry quickly changes as the product picks up process contaminants like metal chips and way oils. The ability of the fluid to tolerate contamination is very important. If a product is formulated with vegetablebased chemistries but doesn't provide system longevity, it isn't truly green." Mattes warns that some vegetable oils may have seal-incompatibility issues unless proper formulation measures are set in place. Also, biological growth can have a potential impact on all metalworking fluids, but the potential can be greater with vegetable-based raw materials. "True 'green' metalcutting fluid solutions are hard to achieve with a product that is diluted with water and recirculated," observes Lee Hitch*censored*, senior research chemist, ITW Rocol North America (Glenview, IL). "You can have bio-based�or plant-based�components that make up your concentrate, but after use and contamination in the sump they may no longer be that environmentally-friendly. "The 'greenest' metalworking fluids are vegetable-based neat oils. These are usually MQL-type lubricants that are used up in the cutting process, leaving behind very little residue and near-dry chips. "Green lubricants," continues Hitch*censored*, "are usually vegetable-oil based, have much better lubricity than mineral-oil based lubricants, and can be used in any metal-removal process. "The limitations of 'green' fluids come in application," says Hitch*censored*. "MQL requires precise application of the lubricant to the tool's cutting edge, which is difficult to do when dealing with large-diameter or deep holes and operations where the cutting edge is masked by the operation. Although these limitations can be eliminated with through-tool application, it can still be difficult when there are many tool changes during one operation." ITW Rocol North America considers bacterial growth a significant issue for recirculated 'green' fluids. "For water-dilutable 'green' fluids, bacteria and fungus are a huge concern," states Hitch*censored*. "These products, usually vegetable-oil based, are much more susceptible to bacteria and fungus [than mineral-oil based fluids]. This is a major hurdle. It took months of engineering for Rustlick to release a new bio-based coolant, Rustlick PowerCool MaxLife Green." Most water-dilutable metalworking fluids contain biocides to combat microbial growth and 'green' coolants are no exception. ITW Rocol North America sees biostability, the challenges of MQL, and cost as barriers to the wider adoption of 'green' metalcutting fluids. Performance is not an issue. "Not every water-based fluid is green," says Wally Boelkins, CEO of Unist Inc. (Grand Rapids, MI). "In fact, some would say that there are no green water-based fluids. There is green neat oil, and green vegetable-based oil. Petroleum-based white oil is biodegradable and nontoxic, so it's technically classified as green. There are some green synthetics. Vegetable derivatives�those derived from seeds�are all green." At Unist, the company's only fluid line (vegetable-based fluids) has always been "green," says Boelkins. "Another thing we say is that our equipment and lubricant reduce 'excess fluid considerations.' This includes reduction or elimination of cleanup, equipment maintenance, recycling, sumps, handling, storage, and disposal. All of these are really 'green' functions." In the case of Unist, the fluid itself is green because it's plant-based, biodegradable, washes with water, and requires no special handling or disposal. Green fluids are almost always used in neat form, according to Boelkins. To achieve their performance they require suitable equipment to deliver the fluid to the cutting edge, and they are used in very small amounts. Unist's Coolube 2210 is a highly refined vegetable-based fluid. Because of the polar properties of vegetable-based fluids such as Coolube 2210 and 2210EP, the product has greater lubricity than a typical mineral-based fluid. Polarity results from the uneven partial charge distribution between various atoms in a compound. Polarity is inherent to vegetable molecules, which are long, heavy, and dipolar�the ends of the molecules have opposing electrical charges. The ends of the molecules have a chemical affinity for metal surfaces, and the result of that affinity is a dense, homogeneous alignment of vegetable oil molecules along the metal surface, creating a durable lubricant film. Mineral oils are nonpolar, and form a random alignment on a metal surface, producing a weaker lubrication layer. There are no real limitations to the types of operations green fluids can be used for, according to Unist, but results may vary. For example, the company says that as far as Coolube 2210 is concerned, when it comes to general machining work, the key is the ability to apply it correctly, so that there is a protective layer of lubricant at the interface between the tooling and the workpiece. "Because our fluid is not used in flood cooling," remarks Boelkins, "we recommend using MQL. So if there are applications where MQL is not possible, then our abilities for 'green' lubrication might be limited." In the case of Coolube vegetablebased lubricants, Boelkins says, there are no issues with bacterial growth. The product has a long shelf life and can sit in the machine lubrication for extended periods of time without contamination or reduction in performance. "The market for green fluids is unlimited," Boelkins insists. "Only a small portion of it has been tapped. Using the vegetable-derivative actually reduces cost�by up to 15% in many manufacturing operations�so cost is not an issue. With our green-fluid concept, we have only penetrated a very small segment of the market�maybe less than 20% of what is potentially our target market, which consists of companies that could realistically implement our 'green' products and environmentally responsible application methods. The market continues to grow because of improved receptivity to these concepts. "The barriers are the conservative nature of manufacturing and the willingness or not to innovate. There are sometimes issues related to cost, because the purchasing or accounting department may look at cost per gallon, but not consider other categories related to cost of usage, such as estimated disposal cost." At Hangsterfers Laboratories (Mantua, NJ), green means using products to their fullest extent. Recycling and proper maintenance will extend fluid life, thereby reducing waste. "High-quality fluids like our Missile Lube Series and PC series may be used for years," says Technical Manager Joe Gentile. "We meet the specifications set forth for vegetable-based content for neat oils, soluble oils, semi-synthetics, and synthetics. These products excel at cutting exotic materials, but they require maintenance just like conventional products." Green fluids and related technologies can be applied to almost every application, says Gentile. "The user is limited only by his ability to adapt to new technologies and or processes." Hangsterfers' Missile Lube waterbased vegetable emulsion, its PC-Series pure vegetable oil, and the new S-700 series water-based vegetable semisynthetic are all green technologies targeted specifically to machining Inconel and titanium. "The lubricity and productivity gains are impressive," states Gentile. "These equate to real cost-per-part savings across the board for our customers. Current machine technologies allow the use of green, renewable-resource products with superior results. Hangsterfer's maintenance procedures are built into both our green and conventional products." Asked about the impact of bacteria on green fluids, Gentile says: "Our position has always been one of balance. We work with nature to deliver a balanced fluid system. Renewable resource fluids do use some forms of biocides. Our position, however, is to use an absolutely minimal amount of biocide, and to formulate with ingredients that are naturally bio-resistant." The "Green" market is virtually untapped, according to Hangsterfers. "Customers are just learning of the benefits of green technologies," asserts the company's Skip Wolford. "As end users come to understand the applications and apply these fluids, they will experience significant cost-per-part savings, decreased haul-out costs, real tool-life savings, and a quantifiable increase in their productivity. Going green means applying every aspect of manufacturing knowledge and capacity to use the human and capital assets already in place. Green is much more than window dressing and slogans. It's a concerted effort to be on the leading edge of technology and environmental responsibility." At Cimcool Fluids (Cincinnati), "green technology fluids" use plant-derived raw materials to replace mineral oil. "Plants are renewable and can be planted and harvested to produce specific and consistent raw materials," says Cimcool's Kevin Tucker. "We can formulate products with these plant-derived materials to make semisynthetics, soluble oils, or even 'neat' oils. Expanding the term 'green' to include 'environmentally responsible' fluids would also allow the inclusion of technically superior products that use and waste less." Scientists at Cimcool say that using plant-sourced raw materials to replace mineral oil is the critical chemistry in producing a green metalcutting fluid such as the company's Cimfree synthetic. Plant-sourced materials can be used to produce vegetable oils, fats, esters, and surfactants. "We've found that our plant-based products can be formulated to provide comparable performance to conventional products," says Tucker. "Traditionally, green fluids may have even better lubricity, because they have excellent boundary-lubrication properties. In the past, plant-sourced materials had shorter life cycles due to oxidative breakdown. Recently, our company has discovered proprietary technology that allows green fluids to have longer sump life, lasting as long as conventional fluids when in use." Green fluids, according to Tucker, really have no performance limitations. The one limiting factor is usually cost. Plant-sourced raw materials can cost as much as 300% more than their counterparts, so sometimes only the most environmentally conscious customer is willing to pay the higher price to use a "green" fluid. "We have had great success machining Inconel and titanium with green fluids," Tucker states. "Recently, however, we've also developed technology that allows us to process these difficult-to-machine alloys with water-based fluids that do not contain mineral oil, vegetable oil, or extreme pressure additives. Through a unique combination of patented and commercial lubricants, we can provide significantly better lubricity than traditional fluids without any of the environmental or performance issues found in other products. We think these fluids are just as "green" as vegetable-sourced fluids, because they don't contain any chlorine, sulfur, or phosphorus that can present waste-disposal concerns." "With our formulations," observes Tucker, "most commonly used premium gaskets and seals are compatible, so very little change to the machining system is required. 'Green' fluids have the same microbial issues as traditional metalworking fluids. Plant-sourced raw materials are even more susceptible to microbial degradation than traditional fluids. "Overall, the potential market for 'green' fluids is the entire metalworking fluids market," says Tucker. "If mineral oil and vegetable oils would ever get closer to each other on cost, the logical choice, in most cases, would be the green fluid. The biggest barrier is cost. Other than cost, today there is no significant reason not to use green fluids." "'Green'" can mean a variety of things and apply to all types of metalworking fluids," says Stephen Mair of Shell Lubricants (Houston, TX). Vegetable ester-based neat oils and water-soluble cutting fluids are a form of green renewable products. To improve worker health and safety, many suppliers are removing harmful components like secondary and tertiary amines, DCHA, barium, chlorine, boric acid, biocides and fungicides, nitrites, and phenols. "Also, cutting fluids can be formulated to significantly lower airborne mist, smoke, and VOCs. High-quality base oils are a key function in this area," Mair remarks. Depending on the category, many green fluids perform as well as or better than conventional fluids. The key is selecting the right fluid that provides the lowest total cost of operation, Mair states. "While green or higher-technology fluids can initially have a higher per-unit cost, they can often be the lowest-total-cost product if users evaluate all fluidrelated costs, such as tool life, productivity, waste minimization and treatment, product quality, scrap reduction, energy consumption, and the impact of health and safety." Some renewable green fluids made from vegetable or rerefined base oils have shown limits in fluid life, paint/elastomer compatibility, and wastewater treatment. Users should research the fluid before using it in large central systems or machines that use sensitive paints and elastomers. As for difficult-to-machine materials: "Yes, certain green fluids can be used on difficult metals like Inconel and titanium," says Mair. "There are green fluids that can machine or fabricate the most difficult of metals while still providing green benefits." Some green fluids are not compatible with existing fluids, so cleaning and recharge is required. Regarding the problem of bacterial growth in green fluids, Mair says: "Green fluids are not immune to bacterial growth, but are not necessarily inferior in that area. Under the right conditions, some vegetable-ester based fluids can provide a stronger food source for bacteria, which increases biological growth and shortens fluid life. Some green products contain biocides or fungicides, others rely on alternative chemistries like super amines, bioresistant emulsifiers and surfactants, and/or oil-free chemistries. Technically, some type of green product could be used today in place of most conventional metalworking fluids. The barriers to more widespread use include higher unit cost, lack of OEM approval, performance versus conventional fluids in certain applications, bad experience with a previous 'green' product, and time and cost to change over." For more information go to: http://www.sme.org/cgi-bin/find-articles.pl?&ME10ART28&ME&20100701&&SME&#article

Increase in profits?? For Real?

Fri, 16 Jul 2010 10:37:00 -0500

Can it actually be that we are starting to see some changes for the better in the industry? I just learned that General Electric announced their first increase in profits since sometime in 2008 when the economic crisis started. This is just one company as I am sure there are more that are starting to see their way out of the tumble we have taken. This news is important, not only for economics, but also for morale among the industry. Companies start to show some increases and the sales move up ever so slightly and then little by little things start to move again. We are all aware that this is going to take some time, but, the increase does help to lighten the spirits. The increase also shows that our industry is important to the customers we serve. These people have been loyal to the industry for years and when they see the increases it has to give them even more confidence in the products they are using. Lets all continue to watch for the increases and do all we can to increase our own profits and sales. Some of the ways we can do that is by advertising and letting people know we are still out there and ready to serve them. There are so many tools available to us now that it is hard to know what is right, but, as we all know, if you don't let people know you are there, they will shop elsewhere. The businesses that are most visible seem to be the most sought after so keep your company out there in their hands, in front of them when they are reading, and when they are searching for things they need.

Remembering the reason for Industry

Thu, 08 Jul 2010 11:22:07 -0500

I am sitting here at my desk wondering how many people actually thought about what the 4th of July really means to us as a country. I know to most of us it means a day off and a celebration in our town and fireworks. But, to alot of people it means a lot more than that. One of the things that have happened because of the wars that have been fought and won and the soldiers that have lost their lives for us, is that in our industry we are able to make machines and products to try to make life easier for people. For instance, because we have industry, we have washing machines, dryers, stoves, etc. You get where I am going with this don't you. It is industry that help keep the nation moving ahead. But, industry would not have been able to do all of these things throughout the years had it not been for all those people that worked so hard so many years ago to make our nation great. Let us keep the nation sound and whole and keep moving ahead in the industry world. Remember to honor soldiers and the people in your communities that volunteer to give their time and their lives so we can have a better way of life for ourselves and our families.

Tool Reconditioning in Trying Times

Thu, 01 Jul 2010 09:10:00 -0500

When does it make sense to recondition metalcutting tools rather than buying new? Will cutting tools of the future eliminate reconditioning altogether? To recondition or buy new? That's a question any user of round tools�such as drills, end mills, and reamers�should consider. The economics of the Great Recession have spurred increased interest in reconditioning. There are many variables to consider in the equation�more than some might think. Geometry, purpose, substrate, and coating all play a part in driving the decision to recondition a tool. Other factors include the value of the part, tool life, complexity of the process, location, and the technical level of the operation. All in all, there are few hard and fast rules, though experts in the fields are willing to discuss general guidelines. The simpler the tool the better candidate it is for reconditioning. "Carbide drills are the most commonly resharpened tools," explains Robert Goulding, technical engineering manager for Seco (Troy, MI). "They are the easiest to do. When the drill gets dull, you can re-dress the front end, or if it is chipped and has heavier damage, it can be repaired by cutting off the worn front tip of the drill and then regrinding it. Simply resharpening it is typical, as long as the back taper is not overly affected. Resharpening a drill affects its diameter less than other tools, which makes it ideal for reconditioning." Dimensional control drifts with each reconditioning. "A traditional drill you might re-use five or six times before discarding it. A drill used for making holes with tight tolerances you might use only three times." He also notes that end mills are the next best choice for reconditioning. The tricky part with reconditioning an end mill is that reconditioning affects its diameter. Modern CNC machines with adjustable offsets make it possible to use them, and Goulding notes that many CNC machines have automatic offsets aided by toolsetting equipment. A larger or more-expensive tool is a better candidate for resharpening. "Typically there's minimal value in regrinding solid-carbide end mills that are less than a half inch [12.7 mm] in diam," notes Bill Sebring, technical director for Niagara Cutter (Amherst, NY), a manufacturer of cutting tools such as solid-carbide end mills, drills, thread mills, end mills, slitting saws, and milling cutters. He believes cutting tools that are good candidates for regrinding are "Christmas tree cutters" and roughing end mills. Christmas tree cutters are typically used in the turbine blade industry, and have a complex and precise form. He notes that advancements in CNC grinder technology make it easier to recondition such complex cutting tools. When a solid-carbide end mill is reground at Niagara Cutter, it's referred to as "remanufactured." At Niagara Cutter, remanufactured solid-carbide end mills are completed on the same type of CNC grinder used to initially create them. Niagara Cutter also uses their own in-house PVD coating centers. Sebring notes that coatings can also determine whether a cutting tool would be reconditioned�CVD diamond coating or diamond-like coating (DLC) typically is not economical to regrind. For cutting tools with titanium or chromium-based PVD coatings, remanufacturing is not an issue, because all functional cutting surfaces of the tool can be reground without first removing the coating. He also notes that, like many tool OEMs, standard practice at Niagara Cutter is to regrind only their own products. Gear hobs and cutters are also expensive tools, and are almost universally reconditioned. "There are some carbide-inserted tools that are usually used in larger coarse-pitch applications for roughing," notes Tom Ware, product manager at Star SU (Farmington Hills, MI) "However, the majority of gear tools are solid HSS or carbide tools that are reconditioned." How long is tool life? According to Ware, some applications may only produce five pieces before requiring reconditioning�others may produce 10,000. Reconditioning is certainly worth it for such tools. Ware reports that reconditioning a gear-cutting tool may only cost 10�15% of the price of a new tool. He reports two significant technical developments in gear hobs and cutters that make them both last longer and easier to recondition�increased use of HSS over carbide, and newer PVD coatings. In particular, he points to increased use of aluminum chromium nitrate coating�trade named Alcrona by Oerlikon Balzers (Liechtenstein)�as advantageous for increasing high-heat cutting and reconditioning. "It is actually easier to remove Alcrona coating than the old titanium aluminum or aluminum titanium coatings," he explains. "The chemicals used to remove it don't attack the base materials, especially in the case of carbide. The chemicals used to break down TiAl also attacked the carbide substrate." Another significant trend Ware sees is the greater outsourcing of gearcutting tool reconditioning. A combination of skilled labor, machine investment (especially in coating units), and programming expertise dedicated to reconditioning tools make in-house operations less attractive to an individual customer, according to Ware. Combining work from multiple sources allows companies like Star SU to maintain CNC machines, largely driven by the CAM programming that created the gearcutters in the first place. Full capacity utilization makes it possible to employ in-house coating tool, and then adjust the grinding program to remove only that amount of wear. As the original manufacturer of most of the gearcutters we recondition, we know how to do quality resharpening." He believes a trend to watch in the future, as more manufacturers stop reconditioning tools themselves and rely on outsourcing, is the turnaround time to get reconditioned tools back. The industry standard of two weeks may decrease as competition sets in. Some companies emphasize reconditioning tools more than others. For example, Unimerco (Ann Arbor, MI) started its facility in North America as a reconditioning service, and later began building original tools at the request of customers. They specialize in drills, end mills, reamers, and other solid round tools, including those with PCD inserts. "While we provide custom-designed new tools to our customers, we also built a system to support reconditioning tools," explains Jim Stead, application engineering manager for Unimerco. "Most manufacturers of tools are set up for production. To recondition tools, they have to break into their production. While we now make new tools, we continue to maintain an entire cell dedicated to reconditioning." Like other dedicated reconditioners, the company also maintains their own PVD-coating facility for faster turnaround time. Their branded Re * New service resharpens not only Unimerco tools but many other brands of tools as well. Stead notes that some original manufacturers are not always interested in�or set up for�resharpening tools. He notes they recondition tools for � to � the price of new. Consistency is key. "Every Unimerco facility worldwide uses the same machinery and processes," he explains. All tools are reground according to reconditioning norms that drive tool geometry. Stead notes that every tool Unimerco makes has a unique part number that points to these norms�drawings, parameter files for fluting and clearing, and EDM profiles for PCD inserts. "For PCD tools, we go a step further and uniquely code each tool, even PCD tools made by other manufacturers." He says that reconditioning PCD tools requires special expertise that makes sense for manufacturers to outsource. "PCD damage can be so slight that a microscope is required to see it." There are situations where it may not be worthwhile to recondition tools. Emuge (West Boylston, MA) offers a reconditioning service for its taps, end mills, and thread mills. "Taps can be resharpened, but they are geometrically a lot more complicated than other tools such as drills," remarks Alan Shepherd, technical director at Emuge. Nonuniformity between new and reconditioned tools is one situation that can be problematic. Because regrinding resizes the tap to a certain degree, that nonuniformity with other taps may cause a problem in processing. "For example, on an automotive transfer line you may have 115 spindles tapping an engine block. When it's time to swap out the tools, if some are reconditioned those tools may be shorter than the others, and the manufacturer has to adjust the spindle to compensate. That takes time, and may be more expensive than simply using new taps, especially if the tap is relatively small and inexpensive." Another example he cites is tapping holes in very expensive parts. Tapping typically occurs near the end of a machining process, meaning the part could carry a lot of value by that time. "For example, an expensive part is the outer ring of a jet engine. It might be 5' [1.5 m] in diam with 70�80 holes tapped into 6Al4V titanium. That forging is so expensive they are not going to risk putting a used tap into the metal." He goes on to note that larger parts, like blowout preventers for oilfield work with holes greater than 1" (25.4 mm), frequently use reconditioned taps. Much depends on the customer and their process. "The big secret on reconditioning tools is knowing when to stop using them," explains Shepherd. "Everyone's situation is unique, but there was one manufacturer of automotive components that would send his taps for reconditioning after two or three thousand holes. He found he could get three uses out of each tap that way, but if he ran the tap to destruction, they might have only tapped a thousand more holes." Niagara Cutter's Sebring agrees. "Some customers will use a cutting tool and take it out of service for regrind before there's any catastrophic failure or significant cutting edge damage." He recommends this approach for any cutting tool expected to be reused. If you "pull" a tool before there is any chipping or significant wear, less material needs to be removed for the regrinding process. Should we expect more tool reconditioning these days? "Many indexable tools are in some cases replacing a form tool," remarks Jack Lynch, rotating products manager, Sandvik Coromant (Fair Lawn, NJ). "You are justifying the higher initial purchase price because of the indexability. The customer no longer has the reconditioning expense." He points to end mills like Sandvik's CoroMill 316, which has an exchangeable head, as a tool targeted for replacing round mills. Seco offers a drill with a Crownloc replaceable head, also designed to eliminate the need for reconditioning. "It has found quite a niche," explains Seco's Goulding. "However, there remain reasons to choose a solid-carbide drill, when high-quality holes with exceptional surface finish and high tolerance are needed." Sandvik Coromant's Lynch also agrees there is a place for solid-carbide round tools, even as he sees growth in indexable-insert or replaceable-insert tool designs. Another limiting factor of indexable solutions is the space needed for clamping. Below a certain diameter, solid tools are the only solution. Another key element of cost that Lynch points out is the need to track and carry the extra inventory needed in the tool-reconditioning process. "It takes discipline and a degree of sophistication to manage a reconditioning process�especially in a complex, high-tech environment," he notes. First, there is the physical process of collecting the tools, packaging them up, sending them out, and receiving them back. Then, identifying their variability and either tracking or separating them properly is vital, so that they are used correctly in the machine, according to Lynch. "Especially end mills. Say you send out a 0.5" [12.7-mm] mill and it comes back 0.020 or 0.030" [0.51 or 0.76 mm] smaller in diam. The offsets in the CNC machine have to be addressed properly to get quality cuts." For more information go to: http://www.sme.org/cgi-bin/find articles.pl?&ME10ART23&ME&20100601&&SME&#article

In this world of business and manufacturing things have taken some real drastic changes in the last couple of years. But that is not news to anyone. What is becoming news is that in this industry, I think we are seeing some changes for the better. Spending time talking with people about their marketing needs, I am finding that there is a little more positive feedback than there was a few months ago. Maybe it is just the warmer weather or that it is almost the middle of the year and they are seeing some increases in profits, or maybe it is just what my father used to call TOC. TIRED OF COMPLAINING. One of the things I have found over the years working in sales is that, business has highs and lows, but they always seem to level off after a while and that is where we are right now I think. This is the time we need to take advantage of this level and get back to the roots of our selling to our customers and marketing to the best of our abilities. By doing this, we will find that we will survive the lows that will come at some point again and be ready for them. We are all in this together and by working together we will overcome the part of the business that makes us wonder why we come to work every day and know that we do because we have a great product to offer our industry.

Top 5 Tips to Creating an Effective Blog

Fri, 18 Jun 2010 09:25:56 -0500

Blogs have made a grand entrance into the marketing realm. Why? They can be a successful marketing tool if done right. Blogs have core components that increase their success such as content, distribution, and frequency, but you need more than that to get people to read it. Popular blogs have one thing in common, an individual voice. A voice will not only gain readers, but it keeps them. Learn how to create your voice using these 5 blogging tips: 1. Create a Blog Personality Don't formulate your posts. Let your voice shine through. Give your blog a personality. 2. Be Consistent in Your Posts Be consistent. When starting out, try to post at least three times a week, preferably every other day. 3. Keep It Simple Don't get caught up in the length of your posts. They don't have to be long. They can be random thoughts or tidbits of news regarding your industry. The key is to make them interesting. 4. Allow Comments Allow comments. You can moderate comments, but comments create the viral effect by allowing your readers to interact with you. You will also want to research and comment on relevant industry related blogs. 5. Focus on Your Title Titles draw traffic. Be creative. Not only do they capture the attention of potential readers, but those search engines love blog titles. A rule of thumb is to keep your title under ten words. For more information read more from Laura Lake at About.com.

Automation by Machine Design

Thu, 10 Jun 2010 14:58:31 -0500

Buying a stand-alone machining center is one thing. Buying one without the prospect of enjoying the flexibility that automation can bring to low-volume, high-mix production, especially at the job shop level, is quite another. Single stand-alone machines, from this point of view, can be viewed as a dead end when it comes to meeting competitive requirements for increased throughput of high-value, complex parts of the highest quality produced with minimum setup and handling. The stand-alone might generate profit today, but how long will the customer be willing to pay for under-utilized labor or missed opportunity due to lack of flexibility. The configuration of machines purchased today can put manufacturers on the fast track to a competitive future. Machining-center design increasingly emphasizes the ability of machines, whether HMCs, VMCs, multitasking machines, or, more recently, five-axis platforms, to accept automation. Machines and their interfaces are being developed according to the dictum that "the days of one machine�one operator" are, or should be, over. The objectives of automation are well accepted, and include higher spindle utilization rates, higher throughput, reduced labor, process consistency, and flexibility to redeploy machines for future production needs. There are a number of important trends in machine design: * Machining centers, multitasking machines, and five-axis machines are being designed to be integrated with pallet pools, robots, and RGVs, and can accept barfeeders, gantry loaders, and other advanced devices. * Robots are being positioned away from the front of machines so that operators have access, and machines can be accessed from the sides or overhead by railmounted gantry robots. * Single and multiple-machine cells are being created with robots on board, while retaining the ability to run machines manually, if so desired. With the growth and acceptance of multitasking and five-axis machines accelerating, Palletech systems from Mazak Corp. (Florence, KY) are automating a mix of dissimilar machine models, as well as lines of similar machines. "In addition to untended load/unload, from stockers from one to three levels high, and robot loading from overhead rail-mounted robots, the next steps in automation are aimed at increased throughput of quality, complex, high-value parts with minimum part handling," says Mike Kerscher, machining center product group manager, Mazak's Cybertec division. Once strictly the province of high-volume, low-mix part production, robots are successfully being used by low-volume, high-mix contract manufacturers. Reliability of robots as measured by longer mean time between failure (MTBF) is unquestioned, and repeatability as seen in the diversity of applications, whether in high or low-volume applications, is filtering down the supply chain to lower automotive-tier shops. The impact of robots on machine tools can be seen in the "Made for Machine Tools" Web site that Fanuc Robotics America Inc. (Rochester Hills, MI) has launched as a resource for machine-tool OEMs, integrators, machine shops, and other contract manufacturers considering using robots to automate a machine-tending operation. The site (www.fanucrobotics.com/machinetool) includes a wide range of application videos that provide real-world examples of how robots can be used to automate machining processes, including turning, grinding, boring, cutting, milling, drilling, EDM, deburring, and metal fabrication. Robots are available ranging from a lightweight six-axis parallel-link robot, to the ubiquitous LR Mate series for welding apps, and in sizes up to that of the M-2000iA robot capable of handling workpieces weighing from 900 to 1350 kg. Robots are fitted with iRVision for 100% inspection, repeatability in the chuck, and finding parts on belt conveyors (2-D) or pallets (3-D). Automation solutions from Makino Inc. (Mason, OH) range from simple cells with a single machine and robot loader to larger systems consisting of machining centers, parts conveyors, robot and gantry loading, automated assembly and inspection equipment, and parts washers. David Walton, project engineering manager, outlines their scope: "We offer customized automation solutions for high-volume, high-production applications like automotive where a number of parts are run over and over again for a total of several hundred thousand parts a year. For contract manufacturers and shops where there is a high mix of parts going across the machining centers, our pallet-handling system delivers fixtures to the machining center under the control of the cell controller." Makino's MMC palletizing system is designed to enable contract manufacturers to run lean and realize more uptime on their machines for a mix of parts, without having to qualify the fixture every time it is removed, stored, and reintroduced to the machining center. The latest version is the MMC-R automation system for fixture-plate distribution with a six-axis robot for tending four and five-axis HMCs and VMCs in high product mix, low-volume production applications. An optional seventh-axis floor track can support additional machines and storage capacities. "Automation objectives are in line with lean running. Manufacturers are able to increase spindle utilization and reduce setup times through accurate and reliable machine loading, unloading, and part storage," Walton says. "By transporting fixture plates in place of a complete machine pallet, manufacturers benefit from reduced part-fixture costs." Most observers agree that the use of robots has progressed beyond just having two robots standing between two machines. "Obstacles to integration into automation systems haven't been the robots, but the machining process itself," according to Gregory A. Hyatt, vice president and chief technical officer, DMG/Mori Seiki USA (Hoffman Estates, IL). "Machining processes that were adequate for manual operation sometimes may not be robust enough for automation with robots. The most common problem is chip control, especially for lathes, or in drilling operations on machining centers, but basically for any operation that produces a long stringy chip." A second parallel area of concern is quality control in automated operations. "You don't eliminate cost if you still have to have a man there doing quality inspection checks. You may make his job easier, but the cost is still there," says Hyatt. DMG/Mori Seiki has developed a method of monitoring the quality of workpieces with its Hydrogage. The principle of the Hydrogage is the same as that for an air gage. Hyatt explains: "We measure the back pressure as the fluid escapes between the plug and the bore or between the C frame and the shaft. Instead of using air to measure, we use the machine tool's coolant at 1000 psi [6.9 MPa], and measure pressure throughout the fluid. Hydrogage can be used equally well on lathes or machining centers. On machining centers, it can be used on critical bores where we have to maintain a bore size by adjusting the boring bar as needed or replacing it with a redundant tool." "RGV palletizing systems are moving toward the job shop," says William Vejnovic, vice president of engineering, Toyoda Machinery (Arlington Heights, IL). "We have focused on low-volume, high-mix of part numbers going through the RGV systems, turning multiple jobs with lot sizes of 20 or less parts per month around, typical, for example, of aerospace jobs shops. Our HMCs are completely modular, designed so that if you buy a stand-alone machine, you can simply change-out a kit on the front end pallet changer to turn it into an RGV-ready machine. All of our spindles, pallet changer, and tool magazines are independent modules that can be swapped out during installation of the machine." The orientation of Toyoda HMCs toward automation in its 450, 550, 630, 800, and 1050-mm machines is seen in the compatibility of the locating surfaces of its pallet systems. "If you buy a machine with an RGV, new or previous machine models from different generations as long as they are of the same pallet size will fit into the system," Vejnovic explains. "Most typical configuration of the RGV system was two to four HMCs with the larger systems having ten machines. Pallet buffer storage is typically in the 20�30 pallet range. Regardless of how many buffer pallets are in the system, we incorporate a chip into the pallet so that another 300 pallets can be stored off line." Flexibility for the RGV system is provided by design characteristics of the HMCs. "For untended operation, an inductive broken-tool detection system, inspection with a Renishaw probe, which are typically utilized for in-process inspection not intended for first article or final part buyout, and Renishaw laser-tool measurement are available. The software has real-time tool checking. Before a pallet is brought into the machine, the software will check to see that the machine has all the right tools in the ATC for the job, matching tool numbers in the job to the machine. In addition, the software has a first-tool flag function that ensures that only a brand new tool in the magazine will be measured, saving noncutting time," explains Vejnovic. "When considering an HMC, it's always important to look at the machine's design to see how readily it will accept automation," says Gisbert Ledvon of GF Agie Charmilles (Lincolnshire, IL). "Some machines are not designed for automation, putting automation in front of the machine, making them inaccessible to the operator for manual operation. Look to see how easy it is to change-out the automation, and whether there is access to the front and side and the worktable," Ledvon. "Another consideration is the machining center itself. We have developed Smart Machine modules with features that enable the HMCs to deliver consistent performance results, which are especially important in running untended." GF Agie Charmilles' Smart Machine modules put intelligence into the milling process by providing communications between the operator and the machine to optimize processes. Modules include APS (Advanced Process System), a vibration monitoring system that makes vibration caused by interrupted cuts, poorly balanced tools, and the like visible as g-load. The latest version of the ITC (Intelligent Thermal Control), the ITC-5x, was developed for five-axis machines with a rotary tilting table or a tilting head and a rotary table. ITC-5x addresses heat drift where mechanical construction is simply not the answer. In spite of exact compensation between tool and workpiece, the position of the rotation axis stored in the control can change, especially in the swiveled levels. To complete the automation process, Ledvon advises automating report notification with a capability like MT Connect to monitor processes, errors, stoppage, tool breakage, and the like. "About 60% of the VMCs we sell are cellular and automated for the flexibility that today's shops need," says Cris Taylor, CEO, Chiron America (Charlotte, NC). "We automate our machines in two basic ways, with robots and with bar or extrusion feeders. In our Flexcell Uno flexible manufacturing system with one VMC, we create an off-the-shelf cell by integrating a robot and a pallet system with one VMC. The robot is on one side of the machine so it can also be used as a manual machine. The cells are compact, can be shipped on a truck, installed, and moved around the shop." The Flexcell Duo takes the robot and VMC combination a step further. It integrates two FZ 08 W or FZ12KW machining centers on 11 m2 of floor space with a workpiece changer and robot with part magazine to form a manufacturing system for flexibility in six-sided machining of complex parts. The two high-performance machining centers can operate independently of one another. Each machine can have two spindles so that one robot can tend four spindles. It is possible to set up on one of the machines while the other is machining. Loading and unloading of one of the machines can take place during machining with either identical or different workpieces. Workpieces are stored on 15 individual pallets. "Our customer base ranges from larger job shops with batch work to tier one automotive suppliers, and machines can run materials ranging from plastics to steel, gold, aluminum, and copper," says Taylor. When Methods Machine Tools Inc. (Sudbury, MA) introduced its RoboDrill Med Cell, it represented the latest progression of the concept which integrates a high-speed six-axis Fanuc LR Mate 200iC robot with the RoboDrill VMC for five-axis machining of medical parts and devices. The initial combination was found in the Job Shop Cell, which was tweaked to simplify and speed changeover to running a different part. "We designed a universal conveyor with tracks that can be made narrower or wider to handle different-sized workpieces in a minimum amount of time," explains Steve Bond, RoboDrill product manager. "That made it possible for the shop to adjust the infeed and outfeed of the cell, changeover a gripper, and be ready for another job." Typical parts machined on the Job Shop Cell include automotive-specific components, valves, and brake components for the RV industry. Still, another step was needed to meet what the company felt could be an effective machining option for the medical-device industry. "We took the idea a little further and said, if we are going to palletize with some kind of off-the-shelf EDM-style tooling like that available from System 3R, Erowa, or Hirschmann, the workpiece could be mounted and loaded onto the five-axis machining center used by medical device manufacturers," explains Bond. As a result, the Med Cell features an integrated macro chuck that enables different parts to be mounted on the same universal chuck base. Any part that will fit in its 6" (152-mm) vise or chuck can be palletized. Because the workpiece is pallet-mounted, parts remain perfectly aligned when moved through other production operations. Typical medical parts that can be machined include bone plates, knees, hip stems, and polymer cups that hold the ball used in the artificial hip. Erowa Technology Inc. (Arlington Heights, IL) has broadened the reach of its EDM-style palletizing systems to include chip-making applications for HMCs and VMCs, from graphite milling to steel cutting, including five-axis machining. "Our automation isn't aimed at the high-production markets. It is designed more for mold and die, aerospace, medical or general machining, typically shorter-run production," explains Erowa's Chris Norman, COO. "The whole idea is to get the operator out of setting up inside the machine, to let him set up off line so that the spindle running time is maximized. Repeatability of our system is 2�m. For palletization of large parts, a dashboard cavity, or a wing spar, for example, that can be moved by palletized fixturing, the MTS system offers repeatability of better than 5�m. Our MTS system allows us to build customized baseplates that cover the table of a large machine with chucks onto which pallets of different sizes can be moved quickly so that setup time is reduced. It isn't uncommon for palletization to allow an operator to do in minutes something that would take hours otherwise," Norman explains. For more information go to: http://www.sme.org/cgi-bin/find-articles.pl?&ME10ART22&ME&20100601&&SME&#article

Tooling to Match Composite Production

Wed, 02 Jun 2010 08:16:35 -0500

It's getting harder to imagine any market that isn't benefiting from the latest developments in parts manufactured from advanced composites. "Advanced composites will arguably dominate consumer and production products, especially in the near future," says Bert Erdel, industry consultant and executive technology advisor, Morris Group Inc. (Windsor, CT), "as they have begun to gain wide acceptance in solving energy-related issues." The rationale for this energy-saving attribute isn't difficult to see in the "lightweighting" and the strength that composites impart to structural components. Their use has taken hold in literally every form of transportation vehicle from rockets to commercial airliners. In fact, there is hardly a category of consumer or industrial product that hasn't benefited from the flexibility in design and the durability in performance that advanced composites deliver. We take for granted that snow skis, snow boards, and jet-powered personal water devices are made from plastic, or that products as diverse as riding mowers and prosthetic devices seem to have always been made from plastics. Nothing, of course, could be further from the truth. The challenges facing advanced composites manufacturers fall into these general categories: * Selecting the right material for the final part. Formulations are available for virtually any end-user environment of temperature, corrosiveness, and stress. * Selecting the tooling material most compatible with the process. Successful processing depends on how closely tooling can match expansion of the part and maintain process integrity over many production cycles. * Selecting the right manufacturing process. The basic process for advanced composite manufacturing, Erdel explains, "involves combining resin, hardener, and reinforcing fiber under heat and pressure to shape and cure the mixture into finished parts. The resin holds the fiber together; the hardener is a catalyst helping to cure the resin to hard plastic. The reinforcement imparts the required properties of strength and flexibility to the composite." Erdel describes the various processes: * "Prepregging involves the application of formulated resin products, in solution or molten form, to a reinforcement such as carbon, fiberglass, or aramid fiber or cloth. The reinforcement is saturated by dipping through the liquid resin. In an alternate method called a Hot Melt process, the low-solvent resin is impregnated through heat and pressure. * "In the filament wet-winding process, continuous fiber reinforcement materials are drawn through a container of resin mixture and formed onto a rotating mandrel to achieve the desired shape. After winding, the part is cured in an oven. This process can also use preimpregnated fiber tows called towpregs. * "In hand lay-up, prepreg material is trimmed and laid down in as many layers as needed over a mold where it's formed to the desired shape. After forming, a vacuum bag is sealed around the lay-up. Vacuum is drawn on the raw prepreg to remove air, compact the part, and serve as a barrier when the assembly is placed in an autoclave for cure under heat and pressure. * "In automated tape placement, the prepreg tape material is fed through an automated tape layer and applied across the surface of a mold in multiple layers." Other processes include resin transfer molding (RTM) and pultrusion, according to Erdel. RTM is recommended when parts with two smooth surfaces are required, or when a low-pressure molding process is advantageous. Pultrusion involves pulling continuous strands through a strand-tensioning device into a resin bath, and through a heated die where curing occurs. The result is a rod or similar profile with a high fiber loading. Composites technology is as much art as science. The challenge is to match as nearly as possible the coefficient of thermal expansion (CTE) of materials used for tooling (molds and mandrels) with that of the composites used for parts. The rate of growth of the tool and material under heat affects cure rate, cycle time, and the strength, surface quality, and durability of the final part, as well as production efficiency and cost. In the 1980s, the industry standard for aerospace applications were tools made from graphite-reinforced/epoxy (GR/EP) composite materials. Tom Sobcinski, tooling segment manager, Remmele Engineering Inc. (New Brighton, MN) explains: "Composite tools provided a close CTE match to the part. Composite tools were light in weight, and the cost of masters could be amortized across rate tools." However, composite tooling at the time suffered from substantial negatives. "They lacked durability for high volume runs, required costly repair and replacement, could fail during cure cycles for high-value parts, and had a limited supply-chain availability," Sobcinski explains. "In the late 1980s, the industry started to shift to metals-based production tooling. Invar, which has a CTE closely matching GR/EP parts, became the baseline for tools used to produce advanced composite parts," Sobcinski says. The durability of Invar reduced total cost of ownership, and tooling would last the life of the program. In addition, a ready supply base of shops emerged that could form, weld and machine Invar, however difficult that might be. Invar 36, a cast iron with 36% nickel, offers a minimal CTE, and was invented for applications that might best be described as delicate, like sensitive measuring devices, watch springs, clock pendulums, and such. Invar has a lower CTE than either aluminum or steel, but is much more difficult to machine, acting more like stainless and producing long, stringy chips. Invar is expensive and somewhat challenging to weld. Invar tooling becomes exceedingly heavy as molds and mandrels are designed for large parts. There is a definite trend toward using composite materials or metal/composite combination materials for tooling, especially for the largest components. "As aerospace OEMs and tier one suppliers have begun producing larger integrated structures, they began to feel the limitations of Invar tooling. The weight of all-Invar tooling can exceed the capacities of handling and layup equipment, and additional weight reduces throughput due to slower cure cycles and reduced lay-down rate on automated fiber placement [AFP] machines," says Sobcinski. The Boeing 787, in particular, has called attention to the challenges of manufacturing composites for the largest structural components. Erdel explains: "In modern aircraft construction, large quantities of aluminum components are being replaced by more complex parts made of fiber-reinforced materials, primarily carbonfiber-reinforced plastics (CFRP). This reduces weight and greatly simplifies assembly and logistics." Erdel explains why graphite composite tooling is appropriate for the one-piece fuselage barrel for Boeing. "The graphite composite fixture can keep thermal expansion as low as possible during the process. In addition to the weight of the mold, all of the fixturing adds considerably to the mass that must be negotiated." New applications for composite materials are emerging and maturing almost daily. Hexcel Inc. (Stamford, CT) has broken ground in Windsor, CO, for a 100,000 ft2 (9290-m2) prepreg manufacturing plant to serve the North American wind-energy industry. HexPly prepregs are epoxy-resin formulations reinforced with glass and carbon fibers and supplied to customers on large rolls. When prepregs are cured under heat and pressure, they form exceptionally stiff structures with a high strength-to-weight ratio. They are well-suited for use in wind turbine blades. Composite blades are lighter and, therefore, easier to install, and are very durable. Wind turbine blades, which can be up to 50-m long, join a familiar lineup of macro-sized parts and structures that have been employed for decades in the aerospace industry for space-based applications and flight. Wind energy is just one industry that is expected to grow its use of composites. Erdel pegs the growth of demand for composites in aerospace at 15% annually, with wind energy expected to grow by 25% annually. In ten years, he believes that wind energy will consume as much carbon fiber as did the entire world in 2008. Composite consumption in 2009 is estimated to be about 5750 tons. The ability to machine tooling materials without distortion is essential for manufacturing tools with complex shapes and tight tolerances. HexTool tooling compound is fabricated from Hexcel's BMI resin M61 for a lightweight, energy-efficient- cure carbon-fiber tooling. Fast heatup and cool-down rates are aimed at reducing production costs compared with tools made of steel or Invar. HexTool can be repaired and modified to accommodate design changes at far less cost compared to other tooling alternatives. The coefficient of thermal expansion (CTE) of HexTool matches that of carbon/epoxy, and is formulated to withstand several hundred autoclave cycles at curing temperature of 356�F (180�C). "The biggest challenge today, especially for high-end applications like commercial aircraft and aerospace, is building tooling that is durable at elevated temperatures and can produce accurate parts. The tool designer has to be aware of the properties of tooling materials used for building molds. Molds are the first and foremost tools you deal with in building composite parts," explains Louis C. Dorworth, division manager, Abaris Training Resources Inc. (Reno, NV). Molds have to be able to provide a dimensionally accurate end part at the process temperature at which the composite material cures, typically 350�F (177�C). Because of the temperature change the choice of mold material is critical to the process. Dorworth explains: "Look at it this way, the composite material is a thermoset resin in a semi-tacky state, when it's laid up. Then the part is vacuum-bagged on the mold and put in an autoclave. As it heats up, the viscosity of the resin drops and flows throughout the laminate. During this time, it is important to maintain the right heat rate, so that the resin viscosity will get low enough to move into any low-pressure areas between the weave of the fabric, or into the honeycomb core cells to provide filleting, and thus bonding, to the core." "In order to control the dimensions of the tool during the cure cycle, low expansion materials are chosen for the mold in order to maintain dimensional tolerance of the part itself. The idea is to have a part that is dimensionally accurate as it comes out of the mold. Because of this, tool design can become quite complex. This requires skilled tool designers who have background knowledge of both the materials and processes involved in making the part, and the materials used to make the mold," Dorworth says. "We've seen disastrous projects where, because of cost or because of a lack of knowledge or inexperience, the tool designers chose aluminum, a material with a high Coefficient of Thermal Expansion (CTE), perhaps because it's easy to machine. Not taking into account that they're trying to make parts using tooling material that grows at a rate about twelve times the rate of the carbon epoxy material used to make the part. Depending on the configuration, aluminum may not be the material of choice for making high-temperature curing parts. "Another factor is that you have to deal with in-process, is in regard to pressure. If I'm going into a pressure vessel with a vacuum bag, I have to have a tool that doesn't leak. Once I seal my vacuum bag around the part, the vacuum integrity of that tool has to be such that it prevents pressure from driving in through leak paths in the tool and into the part. By allowing air or gas into the part during processing, you create voids in the laminate, which will diminish the part's shear strength and compressive properties," Dorworth explains. Tooling for monolithic composite structures has become extremely large. Just how large can be seen in tooling from ATK Aerospace Structures. The low-CTE fiber-placement layup mandrels for the JSF upper wing skin that measures 37 x 13' (11 x 4-m) wide required a welded Invar 36 structure that weighed in at 55,000 lb (24,948 kg). The low-CTE hand layup Invar 36 mandrel for the Delta IV thermal shield measured 5-m in diam and weighed 30,000 lb (13,608 kg), with vacuum-ported end manifolds in a complex contour and 3-D shape. For example, tooling for a wing of the Boeing 787 is so heavy that special air bearings and tugs have to transport the tooling over reinforced floors and support fixturing has to be designed to support the weight of the tooling. In addition, the autoclave has to put out enough energy to heat the heavy metal mass at a rate that is compatible with the requirement to make the epoxy cure properly and flow properly to get the right resin/fiber ratio in the laminate. ATK is working with an industry collaboration team to design a break-down and composite layup mandrel to meet requirements for the largest composite parts. For the 787 Section 43 fuselage, ATK and a team including Alcore, Cytec, Hexcel, GrafTech, Odyssey, and, of course, Boeing have developed a light weight masterless carbon foam/BMI lay up mandrel architecture. The mandrel design is said to be 57 metric tons lighter than one of traditional Invar design, reducing the capacity required for cranes, handling equipment, tooling, and fiber-placement machines. Autoclave curing has traditionally been necessary to produce the surface and laminate quality acceptable for durability of service. Autoclaves can be quite large and expensive. Units ranging from 12�15' (3.7�4.8 m) ID x 30�50' (9�15-m) long are not unusual for the largest structural components. However, autoclave cure limitations include the capital investment required, size limitations, and limited availability in the supplier base. Increasingly, there is a trend toward out-of-autoclave (OOA) processing. Advanced Composite Group Ltd., a member of the Composites Division of Umeco plc, specializes in manufacturing high-performance prepreg advanced fiber reinforced composites for process technologies, including autoclave, vacuum bag, OOA, and press molding. In October 2008, ACG successfully demonstrated the capability of its MTM 4401 OOA-toughened structure prepreg resin system on the first sub-scale wing box demonstrator produced for the collaborative research ALCAS program (Advanced Low Cost Aircraft Structure). ACG is partner in the Business Jet Platform of this Airbus and Dassault Aviation-led, EU-funded program. ACG's main focus in the program is to design and manufacture the lower cover of a structural wing-box demonstrator. This cover would then be used by four other partners (Alenia, Dassault Aviation, SAAB, and Stork Fokker AESP) to complete the structure using different materials, designs, and manufacturing options. The four structures would subsequently be tested to validate and compare the technologies. In OOA applications, carbon fiber and glass-fiber reinforcement are preimpregnated using specially formulated epoxy, cyanate ester, or bismaleimide (BMI) resin matrixes which are used in woven and stitched fabrics or as unidirectional tape formats in tape placement or tape-winding operations. ACG's OOA technology has successfully been processed using only atmospheric pressure and significantly lower temperatures of 140�F (60�C). Remmele Engineering is developing its Invalite hybrid tooling system for advanced composites as an alternative to all-Invar or all-composite tooling. Objectives of the Invalite tooling include weight reduction, durability and stability, reduced cure-cycle time, lower total cost of ownership, and increased capacity for tool manufacture in the supply chain. The hybrid Invar/composite tool features a reduced thickness Invar face sheet and interlocking GR/BMI composite substructure. The Invalite hybrid tooling system is said to reduce tool weight by more than 50%. It's cost competitive with GR/BMI composite tooling, and eliminates the cost for Invar masters. "One of the things we had to do was reduce the weight of the Invar face sheet. A standard face sheet is 0.5" [12.7-mm] thick. Depending on the configuration of the tool we have reduced the thickness as low as a 0.25" [6.4 mm] using special processing," says Sobcinski. Machining is limited to the Invar face sheet and minor composite machining at the interface joint. The substructure can be produced by waterjet cutting. A 4' (1.2-m) Invalite hybrid tool is currently in production testing. For more information go to: http://www.sme.org/cgi-bin/find-articles.pl?&ME09ART18&ME&20090401&&SME&#article