Build a better mousetrap, and the world will beat a path to your door.
There are a lot of would-be innovators in the motor vehicles world who would disagree with that old adage. In this issue of Today’s Motor Vehicles (see pages 24 and 54), leaders at companies touting new materials and processes say simply having a better way of doing things isn’t enough.
You need mountains of test data showing vast improvement in costs or quality, an advocate within the target company willing to champion your cause, and the financial stability to wait months if not years for a big order. Simply having the best technology isn’t enough when trying to woo companies that spend billions of dollars every year on research and development.
Things happen much faster in other industries. The first generation Apple iPad, released in 2010, lacked a camera, weighed 1.5 lb, and had a screen resolution of 1,024 x 768. The iPad Air, released three years later, had dual cameras, weighed 1 lb, and had 2,048 x 1,536 screen resolution.
Is the automotive industry incapable of or not interested in that level of innovation?
Clearly, cars and trucks have gotten better in recent years. Fuel efficiency has been climbing for most vehicles without sacrificing horsepower or safety, new smart phone-friendly technologies are common, and automakers didn’t even blink at the requirement to install rearview cameras in all vehicles by 2018.
The challenge is the scale and risk acceptance of the industry.
Companies spend roughly $1 billion to design each new vehicle offering, and the investments in tooling for manufacturing can run nearly as high. With that much invested, companies need to get production rolling and cars to dealers as quickly as possible to begin recouping that investment. If unproven new technology could delay product launch by even a day, costs could become unacceptably high.
And companies want years’ worth of test results, not a few case studies. For a product developed within the past six months, it’s hard to show how things will perform after 15 years of constant use. But, as General Motors has learned with last year’s massive recall of Chevrolet Cobalts for faulty ignition switches, product liability problems can crop up years after a vehicle has gone off the market. If technology suppliers can’t provide long-term reliability of new systems, the OEMs won’t be interested.
OEMs seem a bit more open to innovations from long-term, trusted partners. Many of the new, high-tech systems showing up on new vehicles come from major Tier 1 suppliers – companies that also spend billions of dollars every year on R&D.
Still, clever, small companies that truly have developed better mousetraps can wither and die while waiting for someone to take a chance on a new way of doing things.
Jim English, president of cutting fluids supplier Tool-X, has a series of recommendations in this issue about how the industry could support creative companies.
What do you think? Are OEMs doing enough to support creative startups? What more could companies do to encourage innovation? Write me at email@example.com to share your ideas for sparking innovation.
Two sets of environmental regulations are working against each other in the auto industry. Regulators have mandated a 54.5mpg standard for fuel economy by 2025, and automakers have responded primarily by shrinking engines – replacing 6-cylinder models with turbocharged 4-cylinder options. Smaller engines tend to burn less gas, so fuel efficiency goes up.
However, exhaust from turbocharged engines is a separate problem. In 2017, the U.S. Environmental Protection Agency’s Tier 3 emissions standards go into effect, requiring manufacturers to mitigate more of the harmful material that leaves tailpipes. Turbocharging – and other fuel-saving technologies that automakers are implementing – lowers exhaust temperatures, reducing the effectiveness of catalytic converters. So paradoxically, standards to make cars greener in terms of carbon dioxide emissions could create problems for nitrogen oxide (NOx) and carbon monoxide (CO) emissions.
“During an acceleration with a turbocharged engine, NOx goes from low to extremely high. At the same time, the gas flow rate over the catalyst goes extremely high, and that has a multiplier effect on the catalyst. So the amount of NOx flowing over the platinum particles gets insanely high. And yet, going from Tier 2 to Tier 3, the NOx emissions are going to have to be much lower,” says Stephen Golden, chief technology officer for Oxnard, California-based Clean Diesel Technologies Inc. (CDTi), a company that develops and produces catalysts for diesel and gasoline engines.
“Turbo downsizing is a lot more fuel efficient, but there’s a lot less heat going into the exhaust,” Golden says. “You can’t have many seconds when the catalyst is not really awake, because you’ll blow by the tailpipe standards before you really get started.”
So far, the industry’s reaction to rising emissions standards has been to use the same materials that have dramatically improved emissions levels since the 1970s – platinum group metals (PGMs) such as rhodium, palladium, and platinum. PGMs are great at pushing oxygen into unburned fuel in emissions, effectively converting hydrocarbons to water vapor, and at pulling oxygen out of NOx and converting that into nitrogen. But PGMs are very expensive, leading to higher material costs and design challenges – such as automakers making catalytic converters less accessible following a rash of component thefts in which criminals would cut the converters off SUVs.
Golden says CDTi’s response is a new catalyst chemistry that requires significantly less PGM materials, while improving the performance of the converter to meet the rigorous upcoming standards. Called Spinel, CDTi’s material uses base metals in a crystalline structure that stores more oxygen than other catalysts. Spinel provides more oxygen to the PGMs when converting hydrocarbons to CO2 and water and absorbs more oxygen when converting NOx to nitrogen. Similar to the shrink-and-boost strategy of the engines themselves, he says Spinel reduces the amount of PGM material but turbocharges the performance.
“As you look at the cooling effect of turbo downsizing on the cold start, the knee-jerk reaction is to increase the PGM loading by a factor of three or four,” Golden says. “It could happen, but it would be very expensive, and it would pressure the PGM supply.”
Start-stop technology, in which car engines shut off at red lights or when stopped in traffic, can also strain catalytic converters, Golden says, because the engines stay cooler, preventing traditional catalysts from hitting their most efficient states.
“With start-stop and some of the hybrids out there, you never get warm enough to fully activate the catalyst,” Golden says. While he dreams of producing a converter with no PGMs, Golden says the solution for now is to make PGMs more effective.
George Lester, president of consulting company George Lester Inc. and an adjunct professor at the Center for Catalysis and Surface Science at Northwestern University in Evanston, Illinois, was on the team at Universal Oil Products (now part of Honeywell) that developed some of the first catalytic converters for cars in the 1960s and 1970s. Lester says the auto industry has studied and rejected low-PGM and PGM-free catalysts many times throughout the past 40 years.
About six years before catalytic converters started showing up on cars in 1975, Lester and his team proposed a copper-iron catalyst to an automaker, assuming that major producers wouldn’t be willing to pay for more expensive PGMs. The original equipment manufacturer (OEM) rejected that approach, he said, because while costly, the PGMs mitigated emissions more effectively and substantially faster than other systems. Since then, the industry has never turned back.
“If you have something that’s marginally different, it’s a terrible matter to try to get it produced,” Lester says. “The car company is manufacturing hundreds of thousands of these units per year, and it’s got something on its vehicles that’s generated 600 million customer miles with a satisfactory experience.”
While he agrees that lower-temperature emissions from turbocharging are creating a challenge for catalysts, he says many OEMs will simply increase the amount of PGM material to compensate. It’s a costly solution, but companies know it will work, Lester says.
“If you try to downsize and turbocharge at the same time you’re trying to reduce precious metals, you’re handcuffing yourself,” Lester notes.
To win support for a new technology, he says CDTi will have to show either a significant cost reduction or a dramatic improvement in catalyst performance – preferably both. And even then, it will have to convince automakers to rigorously test the material for a long time in various environmental conditions. Given those testing expenses and the fact increasing PGM use is effective, he says convincing companies to change is going to be tough.
“If it’s sizable enough, if it makes enough of a difference, they’ll listen. They’ll give you an honest look, but it has to be pretty significant,” Lester says.
In testing, CDTi was able to meet emissions standards on one turbocharged car – replacing a converter that used 58g/ft3 of PGMs with one that used 2g/ft3. On a non-turbocharged car, testing met standards when a 22g/ft3 was also replaced with a 2g/ft3 converter.
Golden agrees that getting companies to consider a new way of doing things is going to be a challenge. But they say Spinel can offer cost improvements beyond simply reducing material costs for PGMs. Throughout the past 40 years, emissions standards have increased several times as catalytic converter performance improved, a cycle driven by improvements in coating techniques, not in radical changes to the materials themselves.
Statistics from the Association for Emissions Control by Catalysts, a European association set up in 1978 to represent catalyst companies, show that in the mid-1970s, catalytic converters had 200 cells per square inch of PGM materials cleaning emissions. Within a decade, that figure was up to 400cpsi, and modern converters have densities as high as 1,200cpsi. More cells in less space has allowed manufacturers to increase performance of converters while reducing their size and weight, but they still use a lot of PGMs.
The techniques that companies have used to increase cell density and improve performance are complex and expensive. Coating companies apply different catalytic materials to converters in multiple layers, leading to repeated coat-and-bake cycles.
“If you look at cross-sections of substrates, you’ll see many layers of materials, lots of architecture and zoning to get more performance from PGM,” Golden says. “It’s become less about the materials and more about the process complexity that’s involved to keep the performance going forward without just increasing the PGM levels.”
He adds that because Spinel’s molecular structure contains the oxygen storage needed to boost PGM performance, many of those complex stages can disappear. Coaters could apply a layer of Spinel followed by a layer of PGMs – a vastly simplified two-stage process.
Supplier to materials company
CDTi Chief Financial Officer David Shea says his company is in the process of converting from a company that makes catalysts for automakers to one that would in addition make base materials for coating companies – effectively going from a Tier 1 position in the supply chain to a Tier 2.
“We’ve been doing this for 15 years, and we believe that we’ve been making the highest-performing, lowest PGM catalyst on the market, but we’re still a niche player,” Shea says. “OEMs want to see scale, global presence, strong balance sheet – then you get into key concerns like quality and technology.”
To roll out the technology, he says the company needs to supply the manufacturers that are already working with the OEMs.
“We would supply these highly enabling powders to other catalyst coaters, taking advantage of their infrastructure which is global and right next to every automotive plant in the world. There is enough PGM savings coming out of this that we’ll motivate the OEMs to embrace this strategy,” he adds.
The key is having the OEM require the use of Spinel material in their order specifications. Automakers already use that ordering system for other components, Shea adds.
“The substrates, the ceramic filters that we all coat, it works the same way,” Shea explains. “We buy those and coat those, but the OEMs direct us to buy this substrate from this supplier at this price. The OEM negotiates that and tells us what we’re going to buy for a vehicle. That model, in the emissions part of the automotive industry, already exists. So we’re working within an existing framework, but we’re moving our spot in the supply chain.”
Golden adds that in the case of substrates, new suppliers sometimes challenge conventional OEM supply orders, suggesting different suppliers of ceramic substrates than the ones on the spec sheets.
“That conversation usually lasts a very brief period,” Golden says. “The mechanical engineers at the OEM make those decisions after a lot of study and testing. They’re pretty confident that they have the right material when they spec it.”
U.S., Chinese, Indian, European, and Japanese emissions standards are becoming more stringent. These global shifts – such as moving from Tier 2 to Tier 3 implementation, with some manufacturers adopting an accelerated phase-in – will likely pressure PGM prices.
Getting the industry to accept a new way of doing things is always a challenge, but Shea says CDTi’s engineers believe they can prove that Spinel will be a more cost-effective solution – in terms of material costs and manufacturing – for automakers.
“Even though Steve’s Holy Grail is zero PGMs, if you can get it down to 2g/ft3, that’s massive improvement,” Shea says.
Clean Diesel Technologies Inc.
George Lester Inc.
About the author: Robert Schoenberger is the editor of TMV and can be reached at 216.393.0271 or firstname.lastname@example.org.
Massive Comau robots, rated for up to 1,300 lb operations, lift aluminum body sides at Maserati’s Giovanni Agnelli Plant near Turin, Italy. More robots, and a few human workers with large weld guns, connect the panels, creating the body structure for Quattroporte luxury sports sedans.
The body shop – where the parts are heavy, the environment is dangerous, and high-quality repeatability is the priority – is where you’ll find the bulk of robots in automotive manufacturing. It’s where Comau, a subsidiary of Fiat Chrysler Automobiles (FCA), has made a name for itself. Typical body shops rely on several hundred robots performing handling, sealing, and joining tasks to convert a series of metal panels into automotive bodies.
But to grow the company, Comau Chief Operating Officer Mathias Wiklund says the company can’t rely entirely on big machines for heavy-duty operations. With the launch of the company’s smallest robot, the 6.6 lb rated Racer3, Comau hopes to win work in powertrain manufacturing and assembly operations.
Pointing to some of the large Comau robots assembling body sides at the Maserati plant, Wiklund says, “We hope to show our industry partners that we can take the expertise that we’ve gained in the auto industry from applications such as this one and translate that down to a much smaller scale.”
Engine and transmission production are the most obvious places for a smaller, light-duty robot, Wiklund says. As with body assembly, robotics can improve repeatability and precision, making them suitable for gasket installation, engine sealing, and pick-and-place operations.
“With body assembly, there were practical issues that encouraged the use of robots,” Wiklund explains. “A person can’t carry 100kg body panels around all day. It’s a physical impossibility. But the main value companies saw was repeatability. Only a robot could weld the exact same spot every time. Powertrain needs to think more about flexible manufacturing, and flexible production.”
As engines get smaller, tolerances are strict and getting tighter with every new program. At the same time, original equipment manufacturers (OEMs) are sharing smaller numbers of engines across a larger number of vehicles, so volumes on each program are increasing. That’s where Wiklund says Comau engineers saw a big opportunity for expansion.
“The market is expecting more and more changes. If you’re thinking about a powertrain manufacturing line today, there’s a lot of automation, and there’s going to be more,” Wiklund says. “You want to have fast changes and flexibility.”
With transmissions, OEMs are introducing six-, seven-, eight-, and even nine-speed automatic gearboxes, adding more gears to transmissions without adding size or weight. Germany transmission supplier ZF fits eight gears in its 8HP70 automatic transmission in a 652mm (25") package. The company’s six-speed 6HP19 is 8% larger, needing more than 708mm (28").
“When you’re fitting more components in a smaller space, you need precision. With a robot, you can be sure you’re going to drop the same part in the same place every time,” Wiklund says.
Trim and finish
Wiklund sees powertrain as the short-term market that could benefit most from a smaller robot. Longer term, final vehicle assembly could also boost efficiency and productivity by adding more automation.
The most manpower-centered portion of automotive plants – trim and finish – is where engines, seats, dashboards, hood ornaments, and all other parts get added to the vehicle. Unlike body shops, where you’ll see one person for every 100 robots, the ratio of man-to-machine is reversed. Tobias Daniel, head of robotics for Europe and the Americas at Comau, says OEMs have typically kept more people than machines in final assembly because there’s significantly more variety between different vehicles (colors, seat types, radio options) than in the body shop, and conditions are safer (no welding or cutting). Still, robots could improve quality and repeatability.
Door seals, for example, tend to be the same regardless of the color of the seats or number of buttons on the entertainment system. Weather-proofing is a major quality imperative, so using robots could guarantee the proper placement of gaskets, weather stripping, and other sealing components.
“Automation is probably the best solution to increasing quality,” Daniel says. “You have the most human touches on a car in final assembly, so the more functions you automate, the more you can improve build quality.”
About the author: Robert Schoenberger is the editor of TMV and can be reached at 216.393.0271 or email@example.com.
Comau multi-metal vehicle future insights
While Comau is investing in smaller robots, it also has introduced systems to handle the wider variety of materials being used in modern cars and trucks. Martin Kinsella, director of Advanced Materials and Process Technology at Comau, describes his view on the future of the automotive body shop:
Automotive material mix will change dramatically throughout the next several years – moving from a predominant use of mild and high-strength steel to an increasing use of aluminum, cutting weight by 20% to 30%, according to Ducker Worldwide Inc. Aluminum is expected to grow to 27% of the volume for body and closure parts, and 7 out of 10 new pickups in North America will be aluminum-bodied by 2025. Internationally, vehicle aluminum content is expected to approach 35 billion pounds, making automotive the most important global market for aluminum.
Innovative joining processes are becoming more mainstream. Technologies, such as resistance-spot-welding, arc-stud-welding, and laser-welding are processes commonly used with steel, and they can have different application requirements when used with advanced materials. So body shops need to accommodate new materials and new joining processes.
Body-in-white will increasingly deploy multiple processes within a single station or along a single line, accommodating the particularities introduced through diverse joining technologies. Take flow drill screwing (FDS); it has been around for quite a while but has been used largely in small-scale, specialty operations. As FDS and similar joining methods move into higher volume operations, manufacturers need to ensure maintainability, uptime, and efficiency of processes within a multi-material, multi-technology framework.
Comau’s response is the ComauFlex advanced manufacturing strategy, a body shop solution designed to help original equipment manufacturers (OEMs) meet changes in the market. ComauFlex ensures:
- Model flexibility with random build sequencing
- Diverse materials and joining methods
- Improved logistics and reduced traffic flow
- Consolidation of direct labor placement
- Compressed program timing
- Reduced facility footprint
- Global support
ComauFlex is solution-focused as opposed to component-driven. Instead of multiple feed points, ComauFlex reorganizes production into two distinct, interconnected areas. The system kits and loads material into part carriers at the beginning of the line and automatically transports it through the build sequence. Robots remove parts as they are needed within each cell.
Faster part feeding and loading allows fewer conveyors and less possibility for breakdowns or part shortages. OEMs can see improvements in both mean time between failure and mean time to repair.
The modular system is built around standard products. Production can be expanded by adding basic robot integrated configurations (BRICs) to the line and relocating final stations. Pre-assembled BRIC cells are ready for installation upon arrival, so lines can expand quickly.
Finally, ComauFlex supports dissimilar materials, ensures operational flexibility, and manages high volumes and multiple models. Comau is investing in a comprehensive advanced materials strategy that focuses on a combination of highly-efficient principles and designs to assemble multiple materials including aluminum, advanced high-strength steel, carbon fiber composites, and magnesium.
In commercial truck production – where vehicles are manufactured with thousands of components produced by several suppliers from different countries around the world – major components require record keeping, and traceability is key. Traceability, the capability of tracking goods along the supply chain, provides real-time information on where, how, and by whom parts are produced and integrated. Such an approach provides means of reducing, controlling, or eliminating recalls during production processes.
An example of traceability challenge is Jacobs Vehicle Systems Inc. in Bloomfield, Connecticut, a manufacturer of diesel and natural gas engine retarding systems and valve actuation mechanisms. To support a request from one of their largest customers for improved traceability, Jacobs was faced with the requirement to add scannable, laser-marked traceability content to the brake rocker arm during manufacturing and assembly.
Just before final assembly, the rocker arm is tagged with a data matrix code – a 2D computer code that includes basic components and manufacturing information – and a human readable content. One key requirement was that the data matrix had to be validated on 100% of the parts and pass a C or higher grade for it to be acceptable. Additionally, the cycle time had to be held within 25 seconds. The 2D code grading process guarantees traceability of the applied mark throughout the assembly process and throughout the lifetime of the product.
On a different customer’s rocker arms, products are marked and validated in a two-step process. First, the operator loads the part in the laser marker; the part is then placed in a nearby vision grading unit that verifies the 2D code grade. Because of this additional step, the process adds another 10 seconds, impacting productivity. Moving to a fully automated solution would improve cycle time, guarantying 100% verification. This option was very attractive for Jacobs.
Fast, automated part validation
After the evaluation of possible technologies to improve performance and cycle time, Jacobs opted for the laser marking capabilities of Foba because of its Intelligent Mark Positioning (IMP) technology. Foba lasers provided some clear advantages to the manufacturing requirement of the commercial truck industry.
Brent Mayerson, manufacturing process control engineer at Jacobs, comments, “The fact that that Foba could do 100% in-system validation eliminated the need for a separate machine. Saving space and operator time were key benefits.”
The ability to validate the data matrix code right after the part has been marked, without the need for an operator to handle the part, eliminates extra handling that directly affects cycle time. The validation process consists not only in grading of the 2D code, but also in validating its unique content, something that would not have been possible on a remote station without adding a tracking process and networked devices. On the new line, the complete grading process added less than one second to the full 20-second process, a significant improvement compared to the other line’s two-step operation. The recorded information, which include date, time, production information, and passing code, is available for storage on a network drive or the cloud and can be used to manage customer inquiries.
Improved laser marking technology
With the evolution of lean manufacturing, suppliers are continuously challenged to find solutions that minimize manufacturing risks, improving yield and throughput while tracking processes in real-time. Traceability of parts and record keeping of manufactured components have evolved from the human readable mechanical recording such as dot peen (micro-percussion created by a hard needle) to state of the art non-contact technology such as lasers. Lasers have opened the doors to faster and more complex marking solutions, like gray scale marking, annealing, engraving, or layer removal. With today’s technology, digital tracking of production processes has evolved and made many tasks easier.
The use of semiconductors and fiber optics in lasers has enabled marking/engraving systems to come in smaller packages that now can sit on the user’s desktop. They are rugged, air-cooled, run on standard power outlets, require close to zero maintenance, and will outlast compact fluorescent, low consumption kitchen light bulbs. Today’s lasers are easier to use, and come with improved mark accuracy, stability, and performance. Combined with their lower costs of production, lasers have achieve a strong market penetration.
Motor vehicle part manufacturers are continuously pushing for further ways of reducing costs of production. Manufacturing space comes at a premium, and manufacturers are always looking at ways of packing more performance and production capabilities within a smaller footprint. Ever-smaller laser markers have to be able to produce marks on a variety of materials from metal alloys to plastics with a higher mark contrast that lasts beyond the life of the product. Traceability content has to fit in tight spaces and needs to meet their customers’ requirements.
Traceability content typically combines a 2D symbol such as a data matrix code, human readable content, and a logo. Data matrix codes are preferred for their ability to efficiently pack information and are readable even when faced with degradation or contamination.
Marking 2D codes come with sets of challenges as many manufacturers require them to meet a certain standard, typically the Association for Automatic Identification/Direct Part Marking (AIM/DIM) standard. The AIM/DPM standard focuses on methods to grade the quality of a data matrix code using characteristics such as the contrast and the uniformity of the mark.
Marking products for traceability
Finding room on a product to place traceability content is often a challenge. Manufacturers and designers tend to use every available space on the part to squeeze all tracking information required. The marked content, such as the lot number, serial numbers, and a 2D code have to be readable by machines and humans. Sizing down the content is not always desirable, particularly with data matrix codes that require some minimum size as they need to be read by most commercial readers.
As an example, a 2D Code with up to 31 characters will end up with a matrix of 20x20 cells. So it can be read from a distance of 150mm (6") by most readers, it will require and area of 13mm2 x 13mm2 (0.5in2 x 0.5 in2). The space available for traceability content is limited, and the mark needs to fit tight within that space.
With limited space, the alignment of the mark can be a challenge as some of it may not fully land on the part. These slip-ups can look innocuous but could have a direct negative impact on the product’s workmanship. To address these challenges, Foba’s IMP technology has built-in validation tools, tools that validate the part identity and automatically align the traceability content to the part. Often, parts from the same family, that can only be differentiated by a hole size or a part length, are easily confused by operators. Validating the part identity adds a layer of safety that prevents the wrong part from being laser marked. The mark alignment feature, on the other hand, compensates for those situations where the part is not properly seated in its fixture and aligns the mark to the part.
Another benefit of using laser systems with built-in traceability capabilities is their ability to be reprogrammed on the fly. Stand-alone, dedicated, industrial vision-based validation systems are not always cost effective. A stand-alone code validation station requires mechanical support structures, electrical wiring, lighting, vision programming, software communication, hardware interface, and data logging. The cost of integrating such a system can easily exceed the cost of a laser built-in tool without the flexibility and turnkey solution of a fully integrated system. Stand-alone systems are typically dedicated to a single product and work well as long as a new or a variation of the product is not introduced. In these situations where changes are needed, production is faced with a fixed transition schedule, forced downtime, and strict implementation schedules.
The implementation of the proper traceability process is a win-win situation for all – designers, suppliers, manufacturers, and consumers. The reality is that the commercial truck industry is in constant evolution. With manufacturers managing parts coming from different suppliers around the world, in case of a recall, tracking without a traceability system would be a horrendous if not impossible job.
Traceability plays a key role not only in managing recall efficiently but most important in preventing them as it is used during the entire production process. For traceability to work, recorded contents, either done by a laser or other form has to be properly accomplished. Today’s laser marking technologies are fast and cost effective. Combined with integrated vision, the technology provides a real-time validation and tracking system that helps reduce cycle times, improve quality, and optimize the supply chain by providing information about component movements. Traceability is a key competitive advantage that resonates with higher quality standard and corporate responsibility.
About the author: Faycal Benayad-Cherif is business manager for software and vision at Foba Laser. He can be reached at 978.263.9560 or firstname.lastname@example.org.
As part of ongoing optimization processes, every procedure in the BMW tool manufacturing plant in Munich, Germany, is examined and improved regularly. To manufacture precision parts for the large shaping and cutting tools used to shape body panels, two Mikron processing centers from GF Machining Solutions have been in continuous use since the beginning of 2012. This improved not just the quality of the parts, but increased the machine runtimes and doubled productivity within one year.
“The constant optimization of all processes has become second nature to us,” explains Herbert Winkler, manager of the mechanical tool manufacturing department at the Munich BMW plant. “The fact that we achieved such effects with the two new machines did come as a surprise to us, but it also served as an affirmation of our efforts.”
The two 5-axis Mikron HPM 1350U processing centers – equipped with tool changers, pallet magazines, and zero-point clamping systems – have made a decisive contribution to optimization measures since 2012.
BMW, Mini, Rolls Royce designs
As one of three sites of the BMW Group for tool manufacturing, the 220-employee Munich staff works closely with the development department to design and manufacture the tools for the car body exterior and structural parts of new models.
“We see ourselves as a partner and supplier for the technologies for shaping and constructing car bodies and virtually get the design into shape,” Winkler adds.
This includes the entire product manufacturing process with planning, prototype construction, engineering, mechanical manufacture, and toolmaking. Approximately 80 toolmakers use five large milling machines and several small- and medium-sized machines. Tools are tested on six test presses with up to 23,000kN pressing force before the Munich staff puts them in operation in stamping plants all across the world. Together with the Dingolfing, Germany, and Eisenach, Germany, sites, the Munich plant manufactures about half of all BMW tools themselves. The other half come from partner companies.
About 500 tools, with an average of four to five operating sequences per tool set, leave the manufacturing plants at the three sites every year. The manufacturing time of the tool sets has been drastically reduced in the last few years because all processes are interlinked with each other. Non-productive processes of mechanical manufacturing have been disentangled from the main processes and moved to units running in parallel. This affects setup and clamping processes, programming, and tool pre-sets.
While BMW was increasing productivity in toolmaking, quality improved as well. This is also necessary, Winkler says, since BMW doesn’t use intermediate assembly. All parts must be delivered installation-ready for tool assembly.
“The image of the machine operator has changed a great deal. The classical milling cutter has become a milling manager who is responsible for the result and all associated processes,” Winkler says.
During the manufacturing of small components, a tool can determine that some parts are too large for small machines and too small for the average machines. That is why suitable processing centers were sought for the manufacturing of components such as blades, shaping jaws, lifting devices, warm re-shaping bowls or sliders, and blank holders and stamps.
“We decided on the two Mikron HPM 1350U by GF Machining Solutions, because they promised the best values in the benchmarking for almost all important facts,” says Jürgen Heinzer, who is responsible for the technical planning and procurement of means of production.
Daniel Princip, mechanical manufacturing foreman of the Munich BMW plant who deals with the machines on a daily basis, agrees.
“We are much more flexible today, more precise and much more productive than we used to be. The Mikrons can be optimally adjusted to almost any manufacturing situation,” Princip says.
GF Machining Solutions employees build the 1350U models of the high-performance milling (HPM) type series using the moving column principle. Marked by the combination of many individual measurements, the manufacturing process results in a one-piece, molded machine bed standing on three feet for a stable basic structure. The table is symmetrical and the guides of the X-axis are arranged on two levels. This results in high torsion rigidity, especially if heavy workpieces are not clamped to the rotary table in a centered way.
At BMW, clamping towers often benefit from the increased rigidity. Beyond this, the linear guides have scraped supporting surfaces, which lead to very high geometric accuracy. The A- and C-axis can be clamped for roughing treatment, significantly increasing the stability and tool life.
“Machines with such basic properties can easily handle even the greatest precision requirements,” says GF Machining Solutions Project and Key Account Manager Michel Eder.
High-torque, high-tech components
High-performance high-tech motor spindles, made by the Swiss GF subsidiary Step-Tec, provide high torque even at a low rotational speed, rotating up to 24,000rpm with an HSK tool interface. The swivel arm, like the rotary axis, is powered directly by torque motors and is water-cooled – making simultaneous 5-axis milling processing possible. All axes are equipped with a direct measuring system.
Both machines are equipped with tool changers that contain 92 tools each. Pallet changing systems, with three pallets each, make parallel setups during the main production time possible.
“This turns auxiliary process times into production times,” Eder explains.
Princip adds, “Our machines now run around 22 hours a day, almost six times as much as five years ago.”
Due to the high rigidity of the machine, surface area finish of workpieces is close to 80% load carrying capacity and only requires half an hour of subsequent lapping work – reducing what had been a three to four hour manual post-process.
GF Machining Solutions adjusted the machines to use dry processing, a system used at BMW since 2002. Compressed air is brought to 12 bar pressure, and the processing zone is air-cooled from the inside via the cutter as well as from the outside. For dry processing chip removal, the conveyor chain is equipped with an active lubrication system because the cooling lubricant of the machine is not available.
With all these functionalities, these two machines by GF Machining Solutions make an important contribution to the productivity increase at the BMW tool manufacturing plant in Munich. Before 2012, 770 small parts were manufactured annually, in 2013 this increased to 1,550 components, with 1,900 parts expected for 2014.
Winkler concludes, “In the results achieved so far due to our entire optimization measures, the two Mikron HPM 1350U machines positively surprised us with their performance capacity, their precision, and their stability. They impressively confirmed our purchase decision.”
GF Machining Solutions