In order to meet the development requirements of heavy freight trains of North America railways, Transportation Technology Center Inc. (TTCI) launched the “Integrated Freight Train Bogie” project in 2011. This project has involved four types of integrated bogies of various companies in the world. The ZK1-K bogies independently researched and developed by CRRC Qiqihar, with completely independent intellectual properties owned by CRRC Qiqihar, were asked to participate in the project, and recently passed the certification of the Association of American Railroads (AAR).

The ZK1-K bogie has excellent performance, with the straight-line operating stability and curve passing performance taken into account, featuring with the low power, quasi-radial function and low wear, and can effectively solve the problems faced by freight trains of North America railways.

In view of the excellent performance of the ZK1-K bogie, CRRC Qiqihar submitted the A Certification Application of the bogie to AAR in 2015. In 2016, the ZK1-K bogie was subject to the AAR M-976 dynamic test at CCTI and passed all the 12 test items. At present, the bogie has passed the AAR M976 Certification; bolsters, side frames and other large parts have passed the certifications such as AAR M201, M202, M203 and M210 and AAR has issued an official letter of approval.

The ZK1-K bogie became the first bogie in China approved by AAR that can be put into operation on North American railways, demonstrating that the high-end bogies of CRRC have approached the North American railway market and laid a solid foundation for CRRC's products to be steadily sold to the North American market.

The ZK1 bogies independently researched and developed by CRRC Qiqihar have been applied to more than 17,000 vehicles in Australia, New Zealand, Kazakhstan, Saudi Arabia, Mongolia, Brazil and South Korea, and the maximum operating time is more than 17 years.

Compared with other modified bogies, the ZK1 bogie is simple in structure, mature in technology, reliable in use, and easy to maintain. It is particularly advantageous in solving the problem concerning the thermal mechanical peeling of wheel treads of heavy axle load vehicles and improving the hunting stability of heavy-duty vehicles. After running 1.25 million kilometers, the rear rims of some vehicles are almost free of wear. Therefore, the ZK1 bogie is highly praised by foreign users.