Large engine blocks can soak up a lot of vibration. A cast-iron crankshaft rotating at 5,000rpm in a 5L V-8 can sound pretty sweet. Up that speed, drop two-thirds of the engine mass, and swap that cast-iron crank for tool steel, and every microscopic flaw is going to be noticeable.
Engine downsizing and turbocharging strategies have allowed automotive original equipment manufacturers (OEMs) to replace V-8s with V-6s and even 4-cylinder engines. That shift has improved fuel economy and simplified vehicle assembly by eliminating the need to support dramatically different engine sizes in each vehicle. On the other hand, keeping those small, boosted engines civilized is a major engineering challenge.
OEM specifications for roundness, smoothness, and dimensional accuracy have gotten more stringent in the past five years, causing headaches for suppliers who now find themselves struggling to meet requirements measured in microns.
Pat Cebelak, on the other hand, doesn’t mind. The president of Lansing, Michigan-based Impco Microfinishing makes machines that remove the last micron or so of material on ground parts such as crankshafts and camshafts. As tolerances get tighter, Impco’s processes become more vital to production.
“The tighter the tolerances, the better things are for us,” Cebelak says.
Crankshafts, camshafts, and similar rotating parts tend to be made from cast iron or tool steel, and manufacturers typically grind them to shape. Impco Global Sales Director Mark Hendel says that the grinding process has become significantly more precise in producing controlled diameters in recent years, allowing manufacturers to produce very good parts without further processing. Unfortunately, nearly perfect isn’t good enough in the smaller, boosted engines in favor today. Avoiding noise and reducing friction require removing microscopic features created during earlier processes – typically by high and low frequency chatter during milling or grinding. That process optimizes the bearing form, creating a functional surface for the rotating part.
“Certain OEMs in Europe are very focused on bringing powertrain surface finishes down to some very fine surface finish values. And they’re not just talking about it. They’re ordering equipment, and they’re doing it,” Hendel says.
Impco’s machines use abrasive films to smooth and shape features on rotating shafts. Arms with tooling shaped to fit over cylindrical bearing journals close around the journals, holding the abrasive tape in contact with the surface for a specified time. Tape abrasive levels vary in grit type, grade, and manufacturer, depending on the bearing form and surface finish requirements, with increasingly fine abrasives to achieve the final finish, he adds.
Creating a functional surface, typically a very smooth one, is the primary goal of the process. Some companies use microfinishing to generate unique geometric features to reduce edge loading, maintain lubricant coverage on rotating parts, to seal a surface, or to guide fluid flow. Impco’s engineering staff works with customers to develop custom processes to generate those features.
“The functional surface that we create is customized to the function of that feature,” Hendel says. “A main bearing diameter, an oil seal, or a thrust face – those are three different component features that need three different types of surfaces.”
Updating equipment, processes
With the need for high-volume microfinishing rising, Cebelak and Hendel say customers have been asking for ways to increase productivity and capacity with the goal of 100% repeatability for every surface on every shaft. With many vehicles sharing engines or variations of engines, quantities for many components are rising, even as the industry diversifies vehicle offerings.
Impco recently shipped its first Worldstar 1680 microfinishing system to Brazil where a supplier plans to make crankshafts for a global OEM. The CNC system automatically polishes critical cylindrical bearing journals for different sized crankshafts, without manual tool changes and repositioning for component pitch. Automating that function reduces changeovers from hours to minutes, processing a 4-cylinder crankshaft through three levels of microfinishing plus thrust-face finishing.
It can automatically position each of 11 pairs of arms in any position to accommodate various crankshaft sizes, allowing one piece of equipment to serve a large engine family. Each microfinishing station in the 4-machine system is loaded and unloaded automatically with an overhead gantry.
“We make surfaces perfectly round and perfectly smooth. That means less friction, more horsepower, less emissions,” Cebelak says. “With the downsizing of engines, the crank has to spin faster, not overheat, and have the right oil layer over all of the spinning parts. Our process allows all of that to occur without breakdowns.”
Fires still smoldered as rescue crews entered the building to look for survivors. An explosion has ripped the factory apart, an accident that could quickly turn catastrophic for the Ford Motor Co.
The May explosion at Meridian Magnesium Products in Eaton Rapids, Michigan, forced Ford to shut down production of F-150 and F-Series Super Duty trucks. Analysts have estimated that each F-Series truck generates between $5,000 and $10,000 in profit, so with nearly 2,400 trucks sold daily, shutdowns could cost the company $12 million to $24 million daily – $1 million per hour on the high side of that estimate.
Had the accident shut off supplies for the Fusion sedan or the Explorer SUV, engineers and executives might have taken some time to weigh various options.
With the F-150, careful consideration and waiting were off the table.
Engineers entered the burning building to pull 19 casting dies from Meridian’s shop floor. Some dies were sent to another plant in the area, but the biggest, an 87,000 lb behemoth, needed to go to Nottingham, U.K. Ford trucked the die to Columbus, Ohio, and put it on a Russian cargo jet to cross the Atlantic. Within a day, it was producing parts for Ford plants in Michigan, Kentucky, and Missouri – parts that will have to arrive via 747 for the foreseeable future.
The rescue mission likely cost Ford millions or even tens of millions of dollars – a regular Tuesday in terms of F-Series profits.
How did Ford put itself in a position where one accident at one supplier could shutter three critical assembly plants? I put that question to Tobias Schoenherr, professor of purchasing and supply management at Michigan State University and co-editor of the International Journal of Operations and Production Management.
For more than a decade, Ford and other automakers have shrunk their supply chains, offering more work to a smaller number of providers. Consolidation has simplified purchasing and given companies more bargaining power.
“These advantages, however, have to be weighed against the risk of becoming too dependent on a supplier or a small set of suppliers,” Schoenherr says. “The repercussions of such risks were evidenced in the recent fire at a supplier site. A similar example – the (2011) Japanese earthquake and subsequent tsunami – also significantly impacted the automotive industry due to single-sourcing decisions.”
He adds that recently, automakers are starting to diversify their supplier bases again. And while consolidation may have played a role in Ford’s vulnerability, a bigger issue was likely the material.
Lightweight magnesium castings are just entering the auto world, and few companies are available to fill the void if a plant goes down. With critical components and vital products, having backup suppliers is ideal, but not always feasible.
“The application of new or rare technologies is risky, but at the same time, the reward can be tremendous because they are so risky,” Schoenherr says.
President Donald Trump is threatening to put large tariffs on cars imported into the United States.
“I met with Secretary of Commerce Wilbur Ross to discuss the current state of our automobile industry,” Trump said. “I instructed Secretary Ross to consider initiating a Section 232 investigation into imports of automobiles, including trucks, and automotive parts to determine their effects on America’s national security. Core industries such as automobiles and automotive parts are critical to our strength as a Nation.”
Section 232 process is legislation that allows the president to use tariffs to protect industries needed for national security such as munitions producers. Earlier this year, Trump used that process to place 25% tariffs on imported steel and aluminum. Such a review would have to find that the auto industry is critical to U.S. security and that it is in danger from foreign trade. While many lawmakers would argue that the industry is critical, the global nature of automotive production makes it harder to figure out the second criteria.
Even more difficult to parse is the talk of automotive parts. Virtually every car being produced today has global parts. Vehicles made in Japan have safety systems made in Europe and the U.S.; cars built in Mexico have engines from the U.S. made with engine blocks from Canada; cars built by South Korean-owned automakers in Georgia use steel from Asia and glass from Tennessee.
So, a large tariff on parts could drive up the cost of cars made in the U.S., and reciprocal tariffs from other countries could make U.S. built parts less competitive than European or South American components.
“Contrary to the assumption underlying the investigation on import vehicles, the U.S. auto industry is thriving,” said John Bozzella, president and CEO of the Global Automakers trade group, an organization that represents German, Japanese, and Korean automakers in the U.S. “To our knowledge no one is asking for this protection.”
Even pro-tariff groups that oppose free trade were wary of endorsing the potential for new duties on imports. During his last press conference with the media, outgoing United Auto Workers (UAW) President Dennis Williams acknowledged that Trump’s positions on trade are closer to the union’s views than other Republicans and most Democratic lawmakers. But, he stopped short of endorsing the action.
“We should have been looking at imports a long, long time ago,” Williams said. “I do support any time we look at these things.”
However, he declined to endorse the action without seeing details on what products would be hit with tariffs and how that would impact U.S. workers. Large tariffs on Canadian engine blocks, for example, could threaten U.S. jobs machining and finishing engines.
Trump has long made an issue of automotive imports, blaming production in Mexico and imports from overseas for declines in U.S. manufacturing numbers. During the past three years, he has criticized Ford for producing vehicles in Mexico, said Japan is taking advantage of the U.S. market by not buying more American-made cars, and that Germany unfairly benefits from open U.S. markets.
However, determining nationality is increasingly difficult in the automotive world. BMW exports more cars from the U.S. than it imports from Germany, Toyota and Honda get nearly all of their sales from vehicles produced in Ohio and Kentucky, and exports from Mexico have been dropping (mostly because Mexico is a base for car production, and U.S. buyers have instead been opting for SUVs and trucks).
Several news outlets called the action a maneuvering tactic, a ploy to get Mexico to offer more concessions during ongoing talks to renegotiate the North American Free Trade Agreement (NAFTA). The earlier steel and aluminum tariffs are another tool in that negotiating kit as the Commerce Department delayed enforcement of those duties on products from Canada and Mexico, but it could reimpose them during talks.
“If these tariffs are imposed, consumers are going to take a big hit because they will have fewer vehicle choices and higher car and truck prices,” Bozzella said. “This course of action will undermine the health and competitiveness of the U.S. auto industry and invite retaliation by our trading partners.”
Steel, aluminum tariffs move forward for US allies
After announcing 25% steel tariffs and 10% aluminum tariffs in February, the Trump Administration delayed enforcement of those on Canada, Mexico, and the European Union, presenting them as targeted measures meant to lessen the impact of Asian exports on U.S. metals production.
At the end of May, however, the U.S. Department of Commerce canceled those exemptions, enacting the tariffs on the nation’s largest trading partners and longest-standing allies.
“Current quantities and circumstances of steel and aluminum imports into the United States threaten to impair national security,” Trump Administration officials said. “These excessive imports are driven in large part by the worldwide glut from overproduction by other countries.”
The U.S. has reached bi-lateral trade deals with Australia, Argentina, and Brazil in steel exports, exempting them from the tariffs; and with Australia and Argentina on aluminum trade.
John Bozzella, president and CEO of the Global Automakers trade group that represents several Japanese, Korean, and European automakers and their suppliers, said, “The president’s decision to impose significant tariffs on steel and aluminum imports from the European Union and our NAFTA trading partners is disappointing and counterproductive. A tariff is a tax and this action will raise prices and hurt American auto producers and their customers. Any retaliation by our trading partners will multiply this harm and do nothing to encourage U.S. exports.”
In response to the metals tariffs, several U.S. trading partners have assigned counter-tariffs to products made here. Canada placed 25% tariffs on a wide range of American steel finished products (the two countries have a robust, two-way metals trade), including pipes and sheet used in automotive production. Canada will level 10% tariffs on a wide range of oddball consumer products ranging from strawberry jam to dishwasher detergent.
Mexico will impose reciprocal tariffs on flat steel (hot- and cold-rolled sheet, coated metal, and various tubes), lamps, pork legs and shoulders, sausages and food preparations, apples, grapes, blueberries, and various cheeses, up to an amount comparable to the level of impact from U.S. tariffs. www.commerce.gov; www.fin.gc.ca; www.globalautomakers.org; www.gob.mx
The Federal Highway Administration (FHA) is dropping Obama-era rules that required several municipalities to track vehicle CO2 emissions – further loosening rules that influence fuel economy performance for vehicles.
“This repeal will alleviate a burden on state departments of transportation (DOTs) and metropolitan planning organizations (MPOs) that imposed costs with no predictable level of benefits. This final rule does not prohibit State DOTs and MPOs from choosing voluntarily to measure and assess CO2 emissions,” FHA officials said in a regulatory filing.
The FHA rules don’t offer automakers direct relief from efficiency rules, such as the Trump administration’s April decision to revisit average fleet fuel economy standards, but they remove incentives that cities had to push for more fuel-efficient vehicles.
The Obama-era Moving Ahead for Progress in the 21st Century Act (MAP-21) rule required cities to track greenhouse gas emissions from transportation year-over-year to determine funding priorities for infrastructure spending. Tracking such emissions could have given cities incentives to create hybrid-only vehicle lanes, special priority status to fuel-efficient vehicles, or other rules that would have encouraged residents to opt for more fuel-efficient cars.
FHA officials said scrapping the rules will save municipalities about $11 million. They also said the rules weren’t necessary as other agencies track and regulate vehicle emissions. The FHA originally suspended the rules in 2017, but several environmental groups sued to block the action. In response, the FHA agreed to enforce reporting requirements until it crafted a new rule. That was the rule filed in late May, set to be effective July 2, 2018.
The U.S. Public Interest Research Group (PIRG), a pro-regulation advocacy group, was one of the organizations that sued the FHA in 2017. U.S. PIRG Transportation Advocate Matt Casale called the reporting rules “essential to minimize the impacts of climate change, which has been recognized by health experts worldwide as the greatest threat to global health in the 21st century. Saving this rule is a major step towards the goal of transitioning to a cleaner, healthier transportation system.”www.fha.gov; www.uspirg.org
US auto production investments
Departments - News
Second quarter automotive capacity expansions include:
Nissan Motor Co. is adding a second 250-job shift to its Canton, Mississippi, assembly plant to increase capacity for NV commercial vans. The plant also produces Titan and Frontier pickups, Altima sedans, and the Murano crossover. www.nissanusa.com
Volkswagen will spend $340 million to add a 5-passenger variant of the sport utility vehicle (SUV) to Chattanooga, Tennessee. The 5-passenger Atlas will mark the third Volkswagen model assembled at the Chattanooga factory, joining the Passat sedan and larger, 7-passenger Atlas SUV. www.vw.com
Spartan Motors Inc. is expanding its Ephrata, Pennsylvania, truck body plant to service a $214 million award granted last year for new United States Postal Service (USPS) truck bodies. Spartan President and CEO Daryl Adams says the expansion will help the company target commercial truck body growth throughout the Northeast by increasing capacity in Pennsylvania. www.spartanmotors.com
Hyundai will spend $388 million in Montgomery, Alabama, to build an engine-head manufacturing plant and enhance production of new Sonata and Elantra sedans. The investment will create 50 new jobs. Hyundai Motor Manufacturing Alabama (HMMA) produces cars and engines, and the engine heads from the new facility will also be used by Kia at its plant in West Point, Georgia. www.kia.com; www.hyundaiusa.com
The TMAC 3.0 tool monitoring adaptive control system uses customized sensors for power, vibration, or strain to measure tool wear. The system learns the cut, allowing the operator to visualize actual cutting to make adjustments.
By measuring tool wear in real-time, TMAC will automatically expire a tool if excessive wear is detected (and can signal a redundant tool) or immediately stop the machine and retract the tool in the event of breakage. Direct interface with the CNC allows machines to run unattended.
A web-based user interface has customizable user views with a dynamic display that can be accessed from any device (including smart phones) and monitors multiple processes, even multiple machine channels simultaneously.
TMAC adaptive control overrides the machine tool feed rate to make automatic adjustments based on the cutting power load of the tool. The system increases feed rates with low power cuts and decreases feed rates with high power cuts and as tools wear. Adjusting feed rates optimizes the cutting process, extends tool life, and reduces cycle times up to 60%.
The MunchMan II conveyor chip and scrap removal conveyor manages long, stringy, and bird’s nest chips generated by high-speed turning and milling operations. It employs a twin-belt conveyor arrangement at the lower curve and through the incline and chip discharge areas of the system. The primary and secondary belts run in unison to grab hold of chips, compress them, and securely carry them up steep inclines, eliminating the risk of conveyor jams caused by chip balls tumbling at the lower curve or jamming in the conveyor incline section.
The MunchMan II can be designed to fit into most CNC lathes and machining centers and has little or no effect on the space required vs. traditional single-belt chip conveyors.
The Axia80 force/torque sensor measures all six components of force and torque and offers stiffness, resolution, and accuracy. The monolithic instrumented transducer also features built-in electronics and silicon strain gages. The sensor connects directly to the robot controller and communicates through EtherCAT or Ethernet. The Axia80 is designed for robotic assembly, grinding, and polishing applications.