The trial section of the Jakarta-Bandung High-Speed Railway (HSR) is ready for dynamic testing and joint tests, according to project builder China Railway International Group.

Last week, the hot-running test of the catenary system of the HSR trial section was carried out, aiming to ensure that the high-speed railway's power supply equipment has met the requirements needed to conduct a series of joint tests.

The hot-running test of the catenary system showed that the essential indicators and parameters of the high-speed train have fully met the design criteria, laying a solid foundation for dynamic testing in the next step.

It was also the first time that the Chinese-made Electric Multiple Units (EMUs), which arrived in Indonesia on Sept 1, appeared on the Jakarta-Bandung HSR track.

Zhang Fangtao, chief designer of the EMUs said his team carried out on-site investigations in Indonesia and adapted their designs to better fit local conditions.

He said there are two main challenges in terms of designing. First is the high temperature and humidity in Indonesia. Second is the complicated geographical conditions. The length and steepness of the slopes on the railway line was totally a new challenge for Chinese designers and engineers.

"In order to adapt to the multi-slope conditions of the railway lines, we set up a rapid acceleration mode on the high-speed EMUs so that the trains can rapidly improve traction performance on the slope," said Zhang.

To achieve the design speed of 350 km per hour, the bodies of the EMUs were made of new types of aluminum alloy material, and were subjected to higher welding standards.

"There are nearly 10,000 welding seams on the body of a high-speed EMU, and each welding seam has a dozen of welding parameters on various aspects, including electricity current, voltage and welding angle. These parameters are important references for our workers, and also ensure the welding quality," said Zhang Heli, a senior welder at the CRRC Qingdao Sifang Locomotive and Rolling Stock Co.

In August this year, the first batch of high-speed EMUs and a comprehensive inspection train tailored for the HSR departed Qingdao port in east China's Shandong Province, marking the first time of sending high-speed EMUs from China to overseas.

"Because of the stormy waves at sea, we put on anti-collision covers for everything inside the high-speed EMUs. To smoothly transport the train from the factory to the port, we practiced a few times, just like a wedding rehearsal, to be familiar with the route," said Ma Qiang, the deputy general manager of the Overseas Business Department at CRRC Qingdao Sifang Locomotive and Rolling Stock Co.

Expected to start operation in June 2023, the Jakarta-Bandung HSR built with Chinese technology will cut the journey between Jakarta and Bandung, the capital of Indonesia's West Java province, from over three hours to around 40 minutes.

The railway is regarded as the link between China's Belt and Road Initiative and Indonesia's Global Maritime Fulcrum strategy.