As part of Toyota’s sustainable model and lean manufacturing processes, Takaoka Plant’s new assembly lines use the most efficient production technology available. Carole Goldsmith reports.
JAPAN’S leading auto manufacturer, Toyota Motor Corporation (TMC) last year installed a revolutionary new assembly line at Takaoka, its largest production plant in Toyota City, Japan.
Designed to reduce space for vehicle production, the company expects this shorter assembly line to cut CO2 output by 50 per cent and lower the energy required to produce vehicles by 20 per cent.
As part of Toyota’s sustainable model, plant initiatives and lean manufacturing processes, Takaoka Plant’s new Assembly Line No. One commenced production in August 2007. The Line uses very efficient innovative production technology.
According to TMC’s assistant manager corporate communications, Paul Nolasco, “the Takaoka Plant currently has three production lines, including the revolutionary new line. We are also planning a new Line No. Two around 2010 and then only the two new lines will operate.”
“As these new lines are much shorter than the conventional production lines, they will use less space. That means a decrease in electricity usage though reduced lighting, air conditioning, heating and energy used, resulting in lower CO2 emissions,” Nolasco said.
Each of the three existing Takaoka production lines currently manufacture 220,000 vehicles per year (that is, 660,000 in total).
“When both of our two new lines are installed, the Takaoka Plant will produce 500,000 vehicles per year, from only the two lines,” Nolasco advised. “Even though the number of vehicles produced annually will drop to 500,000, the output from each of the two lines will be 250,000 vehicles per year. That is an increase of 30,000 vehicles produced from each of the two new shorter and more efficient lines.”
He added that the Takaoka Plant does not have to manufacture as many cars as before, as TMC is producing more vehicles abroad.
Production processes in Line No. One
Stamping, welding, painting and final assembly are conducted on Line No. One. According to Nolasco, “The new line has a stamping machine that is lighter, smaller and moves 70 per cent faster than on the older lines. The machine also uses high-speed conveyor robots researched and developed by Toyota for manufacturing processes and produced by external robotic companies.”
Nolasco said these robots work 70 per cent faster than the other Takaoka plant robots, thereby drastically increasing productivity.
The traditional method on the old assembly lines, of applying the three required layers of paint to the vehicles, primer, colour base and clear colour, has been to allow each layer to dry before applying the next layer.
“The new painting process on Line No. One has reduced the painting time by 40 per cent,” said Nolasco, “using robotics, each of the three paint layers are applied one after the other, all drying at the same time.”
Electro static painting is used, in which an electric current is introduced into the paint and the vehicles are rust proofed during the painting process. Automatic Guided Vehicle conveyor belts move the auto parts on to the next production process on the new assembly line.
“Through all processes operating on the new assembly line, the large conveyor processes are expected to reduce problems, errors and defects by 50 per cent and the CO2 output is predicted to be cut by 50 per cent from reduced heating, air conditioning and ventilation. It is also aimed at lowering the amount of energy required to produce vehicles by 20 per cent,” said Nolasco.
A typical TMC manufacturing plant in Japan produces three or four types of vehicles at the one time. The new Takaoka plant will be able to manufacture up to eight different types of mass produced cars on each of the two new assembly lines when they are both operating.
The new assembly line processes will also reduce the amount of available stock, with 100,000 less vehicles per year produced at Takaoka, in line with TMC’s lean manufacturing production processes.
Innovative robotics in use
Nolasco advises that robots ‘with eyes’ on Line No. One use their ‘vision’ to automatically set the car parts into the required position on the assembly line.
“We also use Toyota Partner robots that work with our employees and do tasks like carrying heavy components. It is teamwork between robot and humans. To get a heavy part from that high shelf, the human guidance to the robot is very important.”
“Toyota has a history of developing robots that are made to work with people. The ultimate objective of TMC car manufacturing is not automation, the ultimate goal is to produce best quality cars,” said Nolasco.
Their development has been guided by “jidoka”, the Japanese word for automation, combined with the Japanese character for person – to suggest a human presence in the process and the investment in machines with human-like intelligence. This concept it outlined in TMC’s 1998 publication, “The Toyota Production System – Leaner Manufacturing for a Greener Planet”.
Plan for a low carbon society
TMC unveiled an Action Plan on June 11th aimed at contributing to a low carbon society through initiatives in the areas of research and development, manufacturing and social contribution. Titled “Toyota Strengthens Initiatives for Low Carbon Society”, the full report on the Action Plan is available online at: http://www.toyota.co.jp/en/news/08/0611.html
The new Takaoka Plant assembly line is one of the many sustainable plant initiatives planned at TMC, as documented in the Plan.
The report reveals that the role of nature is emphasised through the creation of production sites that are in harmony with their natural surroundings. TMC is implementing its “Sustainable Plant” activities with the following in mind:
– Energy reduction through development and implementation of low carbon production technologies and through daily kaizen (improvement) activities;
– Energy conversion using photovoltaic and other renewable energy sources;
– Tree planting to foster exchanges with local communities and protect ecosystems – in May, volunteers from the local community and TMC participated in Japan’s largest tree-planting event (as surveyed by TMC), with approximately 50,000 trees planted.
