"Kaizen forever": Japanese OEMs and suppliers see manufacturing efficiency as key to future competitiveness - Manufacturing Roundup

Automotive Industries, Oct, 2002 by Mike Hara

Most analysts feel that manufacturing remains the cornerstone of the Japanese auto industry's success. Many also feel, based on record profits reported in the most recent fiscal year, that the gap between Japanese automakers and their competitors in North America and Europe may be widening again.

Much of what is being done is incremental through "kaizen" or "continuous improvement" activities and "lowtech" refinements in machining and processing technology For instance, at Suzuki Motor Co.'s new No. 3 assembly plant in Kosai, the company reduced work stations on its No. 1 line from 150 to 115 by such measures as combining window washing, brake fluid, steering fluid and long-life coolant injection into a single process.

Likewise Honda, in overhauling its No. 1 and No. 3 Suzuka lines in the summer of 2000, cut manpower requirements and utility costs by one-third and one-fourth respectively. It made these gains through the introduction of lighter, more versatile manufacturing equipment along with new labor-saving processes including expanded usage of modules.

Welding costs, for instance, were cut in half by adopting "flexible" welding jigs and general-use pallets. Motoatsu Shiraishi, Honda senior managing director in charge of manufacturing, says, "We developed jigs that were not dedicated to specific models. We also installed common transport processes employing generaluse pallets and, to the extent possible, standardized body specifications between models."

Other features of the plant, in the process af being introduced at mare than a dozen Honda assembly plants around the world: Spot welding speed was doubled by switching to electric-driven robots and by adopting a new server gun" welder. Developed and produced by Honda Engineering Co., the new welder contributes to a 46-second takt, 20 percent faster than before.

Bodies "in process" and energy consumption in the paint shop were slashed 25 percent and 30 percent respectively. Through simplified preprocessing and improved zoning, shop dimensions were reduced by one-third from those of its predecessor.

General-use carriers, designed with common pickup points, allow the paint shop to accommodate all models in Honda's present and future lineup. Plus, the unit's small body mass and light weight contribute to energy savings.

Another example of low technology can be seen in Mazda's recently renovated Hiroshima engine plant. From the main assembly line, the automaker's new inline four-cylinder engine, which powers the new Atenza (Mazda 6), is transferred to a dedicated work station, where small plastic cartons, each containing around 50 components, are brought to the line for manual assembly.

Through TPM activities, Fuji reduced sudden equipment failures at its Yajima plant by more than 95 percent and machining defects by an estimated 90 percent since the early 1990s. Yajima experiences fewer than 100 line stoppages each month due to equipment failures.

Elsewhere, Mazda introduced a new painting process at its Hofu plant that combines the primer and top coats into a single operation. thus eliminating the need for one of four paint ovens. The result is a 15 percent increase in line speed and comparable decrease in energy consumption.

Central to the process is a new "interface control" resin. Developed jointly with Kansal Paint Co. and Nippon Paint Co., the resin (a polyacetal) is dispersed throughout the primer. After application, it rises to the surface, separating the primer and top coats.

Mazda expects to complete installation of the new process at its domestic assembly plants by the middle of next year. Estimated savings from the installation are on the order of Y2 billion ($17 million).

In the powertrain field, Mazda brought on stream one of the world's most efficient engine manufacturing facilities--the 36-year-old Hiroshima plant. At the heart of the reported Y25 billion ($200 million) facility renovation is an all-new aluminum casting line that employs the "cold box" method of Cosworth Technology Inc. to produce key components such as the block, camshaft and crankshaft; a high-speed machining line that reduces processing time by more than 90 percent; and a final dressing line that allows sequential assembly of both gasoline and diesel engines, an industry first.

Through these developments, Mazda developed an all-new inline four-cylinder engine with an aluminum block that is 10 percent less costly to produce than one made of cast iron. Insiders claim that cost of a fully dressed engine has been cut to below $1,200. More significantly, Mazda claims that its inline four-cylinder engine is 5 to 10 percent cheaper to produce than the same engine manufactured by sister plants at Ford's Dearborn, Valencia and Chihuahua operations.

Naturally, cost-cuffing extends into the supplier sector. Toyota, for instance, wants to trim Y1 trillion ($8 billion) from its parts bill over a three-year period through fiscal 2004. Other Japanese carmakers are equally aggressive, though their business scale is smaller.