Make no mistake: In order to be competitive in the European auto market, auto makers and suppliers must have a significant amount of their portfolio dedicated to diesel powertrains and components, for the simple reason that more than 50% of European car buyers are opting for diesel engines. That’s why Japan’s Denso Corp. (www.denso.co.jp/en) is committing a significant portion of its European resources to develop advanced common-rail injection systems, basing its manufacturing in the city of Szekesfehervar, Hungary*, where low-wage, high-skilled labor is abundant. Here, Denso has produced more than one-million common-rail systems since April 2004, and expectations are for demand to increase 60% this year. While Denso’s largest customer remains Toyota—Denso was a former member of the Toyota keiretsu until its separation in 1949—its European customer base includes Ford, Opel, Nissan, Fiat and PSA Peugeot Citroen. The supplier’s common-rail systems are found in the Toyota Avensis, Opel Meriva and Corsa, Nissan Pathfinder, PSA Jumper, Ford Transit and Fiat Ducato.
Having introduced its 1,800-bar common-rail system utilizing piezo injectors into the market in May 2005, Denso is ready to take a significant step when it introduces its third-generation 2,000-bar solenoid common-rail system in 2007, which will be quickly followed by a 2,000-bar piezo system in 2008. The switch to the new system will provide compliance with new Euro IV and V emission requirements, along with increases in overall fuel economy. The goal is to provide systems that emit less noise, improve atomization, and provide greater low-end torque. Denso says the advanced common-rail system will provide up to nine injections per cycle, as engineers have designed group holes (no larger than six microns in diameter) in the injector nozzle to provide a wider vapor area. The Szekesfehervar plant will be the main supplier of the 2,000-bar system to European OEMs. Nissan, Toyota and Isuzu are already on-board for the new system.
The 657,000-ft2 facility, with its 3,000 employees, provides $517-million in annual revenue to Denso due in part to the fact that workers here earn roughly 1/8 ($661/month) the rate of their Japanese counterparts. While many of the parts for the common-rail system are still machined at Denso’s lead common-rail plant in Nishio, Japan, European Union requirements stipulating a minimum of 60% localization dictates Szekesfehervar will likely experience an increase in activities, although employment is expected to come down as Denso places added pressure on productivity improvements. Inside the plant there are signs exhorting workers to boost productivity by an overall 25%—and even signs that indicate there will be a headcount reduction of 562 workers. Management wants to cut die change time by more than half, to less than 15 minutes. While dies for the parts currently come from Japan, Denso is seeking Hungarian suppliers to fulfill those functions, although finding reliable suppliers in the country is difficult, according to Satoshi Nagasaka, executive vice president of diesel products manufacturing at Denso Hungary: “Most of our Hungarian suppliers have business with our competitors”—Bosch and Delphi—“but those suppliers we selected without our competitors’ business had very big quality problems. We had two or three suppliers that had not so good performance.”
A critical part of the common-rail system is the nozzle orifice, and manufacturing this piece requires exact precision. Denso utilizes abrasive flow machining technology developed by Dynetics, Inc. (Worburn, MA; www.dyneticscorp.com) to assure orifices are polished and finished to improve fatigue strength. The procedure involves injecting abrasive slurry through the orifice at various pressures until the radius and width of the orifice meets specifications. This process will get increasingly complex as more injections are required in future generation systems, along with accommodating varying degrees of fuel quality in different regions of the world.
Denso’s commitment to the European diesel market is a significant step for the supplier, as it seeks to increase its share of the European market. Challenges will persist, however, as it tries to compete against the long-established players in the region, most notably Bosch and Delphi. But the fact that Denso is willing to stick its neck out by pledging to take risks, seeking to exceed expectations via improvements in fuel economy and power, is more than commendable. Denso officials admit the 2,000-bar system is probably as far as they can go in terms of pressurization, but there’s little doubt they will continue to press on into the realm of HCCI (Homogeneous Charge Compression Ignition) and other technologies that will lay the groundwork for the next milestone in engine performance.—KMK
*The capitol of the country until the 16th century, located on the northeast fringe of the Bakony Mountains.