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Two of China's high-speed trains reach speeds of 420 km/h during test runs in Zhengzhou. [Photo by Luo Chunxiao/China Daily]

Two bullet trains designed by Chinese engineers passed in opposite directions at 420 km/h on Friday, in an experiment carried out by China Railway Corporation that set a world record.

"The success of the experiment demonstrates that China has mastered comprehensive knowledge of the bullet train's core technologies," said Zhou Li, director of science and technology administration department of the cooperation. "It also shows that China's high speed train technology ranks among the most advanced in the world, and some technologies even lead the world."

The tests measured the performance of China's bullet trains, particularly the traction, brakes and software, which now uses Chinese technologies.

"We also gained data about energy costs and vibration noise, discovering the key parameter changes when traveling above 400 km/h," he said.

According to Lu Yang, chief researcher of the China Academy of Railway Sciences, the experiment collected data and tested the train's performance parameters when passing at speeds from 200 km/h to 420 km/h.

"Operational bullet trains usually travel at about 300 km/h. But for new designs, it is necessary to carry out experiments at higher speeds to test various functions and performance parameters," Zhou added.

"The success of the experiment shows that China's high speed railway technology is able to cater to various needs from different countries," Zhou said, adding that it will benefit sales of China's bullet trains overseas.

China's high-speed rail network has more than 19,000 km of track, accounting for 60 percent of the high-speed rail network in the world.