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Train Passes with Flying Colors
When China's first maglev (magnetic levitation) train went into trial operation in the suburbs of Shanghai on December 31 last year, its impact went beyond China's borders, evoking mixed reactions internationally.

Some have criticized it for being too costly -- around US$1.2 billion for the 30-kilometer track -- and doubted it would ever break even. Many more hailed it as a technological marvel that symbolizes the ambition and the dynamic spirit of the city and China as a whole.

The authoritative US-based magazine Engineering News Record compared the project with a delayed similar initiative in the United States and praised it as "a symbol of a country's willingness to make a break with the past."

The project's initial operation appears to be unexpectedly encouraging in financial terms.

The maglev itself has become a tourist site and attracted a lot of visitors.

Local residents have reportedly taken the maglev train to tour the city, rather than for their everyday transportation needs.

An auction of the right to name Shanghai's maglev will soon be held to recover part of the investment. Linking central Shanghai with Pudong International Airport, the maglev line allows the trains to travel at a speed of 430 kilometers per hour, compared with an average speed of less than 100 kilometers per hour of other trains currently operating in China.

Electromagnetic fields are used to propel the train and suspend it by one centimeter in the air on a steel-plated guideway.

The 30-kilometer ride through the once congestion-prone area takes only 8 minutes.

Huge investment from the Shanghai city government and subsidies from the German Government, which wanted to export the German-developed transport system, made it possible to have the project up and running within a stunningly short time of 22 months.

The project was jointly built and managed by the Transrapid International consortium led by German and Chinese companies.

German firms built the power and control equipment and supply the trains.

Chinese companies built the magnetic track and elevated guideway formed by 2,550 girder sections, each weighing 170 tons and measuring 25 meters in length.

Technical Hurdles

As the first commercial maglev line in the world that will go into commercial operation, the Shanghai maglev has encountered many previously unseen technological challenges in railway construction and design.

The girder sections that form the backbone of the maglev line represented one of the toughest engineering tests in the Sino-German project.

The high speed of the maglev trains requires a high level of precision in both the manufacturing and installation of the 2,550 girder sections.

Any error in measurement beyond the thickness of a human hair cannot be tolerated, said Song Xiaoke, vice-chairman of the Shanghai Maglev Co, the Chinese developer and operator of the Shanghai maglev.

While the company was in talks about the project with its German counterpart two years ago, it was told the digitally controlled precision lathe used to make the girders would itself take two years to make in Germany, plus another six months for test runs. This apparently exceeded the deadline for the whole project.

The company then turned to Chinese lathe manufacturers, sending bidding invitations to six major companies.

In January 2001, the Shenyang Lathe Co won the bidding with what was judged the best plan and shortest promised delivery time.

A task force was soon established and a special assembly line was set up at the Shenyang company.

All the design work was completed within 45 days, compared with the usual 180 days. "The time was really short yet the assignment was important not only in economic but political terms as Premier Zhu Rongji was said to be concerned about the project," said Zhao Yuwei, a spokeman for the Zhongjie factory under the Shenyang company that took the assignment.

The assignment, though not the largest the factory ever took in 60 years, was indeed its "No 1" project at that time, according to Zhao.

To meet the tight schedule, technological experts rescheduled their own designing process, he said.

Eight months later, the first lathe was delivered on time and the engineers used it to make the first girder as required.

On September 5 last year, the last of the girder sections was completed and put in place, 40 days ahead of schedule.

If the manufacture of the digitally controlled lathe epitomizes the high speed and precision of the project, the design and installation of the girder sections may well serve as a good example of the project's innovativeness.

The original specifications of the girders provided by the German firms requested that each section be 50 meters long and weigh 350 tons. The sections were all to be connected with great precision to ensure the safety of the high-speed ride.

Yet later calculations by engineers from the Institute of Public Facility Design of Shanghai, the Chinese technological supervisor, found such sections might be too large for transportation and precise installation.

The original specifications were derived from an experiment on a trial girder section in Germany and proved not very suitable for the local conditions in Shanghai, said Xie Ying from the institute involved in the project.

The Chinese engineers, after mulling over a set of proposals, took a bold step to resolve the issue.

They decided to revise the original specification and cut each girder section into two equally long pieces, thus facilitating the installation and transportation without compromising the quality and security of the project.

In addition, they made a few more innovations to the guideway to improve the comfort of travel.

All the revisions were successfully completed within 60 days, ensuring the inauguration of the maglev according to its tight timescale.

Despite the high cost of the Shanghai maglev, the technology and experience gained by the Chinese engineers and companies may prove invaluable in the construction of future, longer maglev lines in China, experts said.

"The Shanghai maglev line is not merely for commercial purposes," said Yan Luguang, a Chinese maglev expert and long-time advocate of its operation in China. "It is a prototype of China's maglev industry."

He claimed experience gained in the project may lead to domestic production of the relevant equipment in the future, thus reducing the costs of future maglev projects.

And China may gain much more experience than any others as the operator of the first commercial line in the world, Yan said.

In fact, a 1,300-kilometer maglev line linking Beijing and Shanghai had been proposed long before the Shanghai maglev line began but the proposed project between the two cities has constantly been called into question by many rail experts and the press over its technological and financial feasibility.

Another line linking Shanghai and the tourist city of Hangzhou in East China's Zhejiang Province over a distance of 200 kilometers was also proposed when the Shanghai maglev line was under construction.

If the Shanghai maglev runs smoothly when it goes into formal commercial operations at the end of this year, this could make it more likely that the other two proposals will get the go-ahead, Yan said.

(China Daily February 19, 2003)

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