On July 17, CRRC Changchun Railway Vehicles Co., Ltd. officially released a built-in bogie for high-speed rail that meets the requirements for operating EMU trains at a speed of 400 kilometers per hour, marking a breakthrough in China's deep control over HSR core technologies and development of key components.

Compared to traditional external bogies, this built-in bogie reduces weight by 20%, resulting in a 15% decrease in vehicle operation energy consumption, approximately 30% reduction in wheel-rail wear, and a decrease of around 2 decibels in wheel-rail noise. Over the entire lifecycle, maintenance costs for the track and bogie are lowered by 15%, which will promote greener and more energy-efficient EMU trains.

Designed to operate at a speed of 400 kilometers per hour, this built-in bogie has already been tested at a speed of 600 kilometers per hour on a test bench, meeting all technical requirements for EMU trains operating at 400 kilometers per hour.

The development of the built-in bogie for high-speed rail incorporates several innovative technologies. The R&D team pioneered the use of composite material leaf spring technology in the railway industry, solving the issue of insufficient transverse space for the built-in bogie by fully utilizing its longitudinal dimensions to transform the available space from wide to long. By employing hydro-pneumatic suspension technology, the damping function of a series of dampers (the bogie has two series of dampers, equivalent to two levels of shock absorption) has been enhanced to improve the anti-rollover ability of the built-in bogie. Additionally, the mature structure of the bogie's arm positioning has been retained, making it suitable for high-speed operation of EMU trains.