Research on the interchangeability technology of foreign standard rails and national standard rails

Research on the interchangeability technology of foreign standard rails and national standard rails

• What core technical indicators must be met for rail interchangeability?​

Core indicators include gauge matching accuracy (error ≤±0.5mm), mechanical property compatibility (tensile strength difference ≤50MPa), and profile conformity (rail head shape deviation ≤±0.3mm). For example, when using European - standard rails on Chinese railways, it is necessary to ensure that the rail base width is compatible with domestic fasteners. Finite - element simulations are used to verify the mechanical responses of different rail - sleeper - fastener combinations, ensuring system stability.​

• What is the impact of rail head profile differences on rail interchangeability and the solutions?​

American - standard rails feature a rounded transition design for the rail head, while Chinese - standard rails have a specific slope. These differences change the wheel - rail contact stress distribution. By establishing a wheel - rail contact mechanics model, optimizing rail head profile parameters, and developing transitional grinding processes, the change in contact patch area can be controlled within 10%, reducing wheel wear and noise, and enabling the safe interchange of rails with different head profiles.​

• How do differences in rail chemical composition affect welding compatibility?​

Japanese - standard rails have a relatively high copper content (0.2% - 0.4%), prone to thermal cracking during welding. Adopting a "preheating + multi - layer multi - pass welding" process, increasing the preheating temperature to 200 - 250℃, and using special welding wires with a nickel content of 8% - 10% can inhibit copper segregation, making the tensile strength of the welding joint reach over 92% of the base metal, meeting the welding interchange requirements of rails with different chemical compositions.​

• What is the implementation process of rail interchangeability in transnational railway projects?​

First, conduct a comparative analysis of rail parameters and establish a difference database. Second, carry out laboratory simulation tests to verify the feasibility of the interchange plan. Then, conduct on - site test laying and monitor track geometry and dynamic performance. Finally, formulate transitional technical specifications, clarifying interchange conditions and maintenance standards. During the construction of the China - Laos Railway, this process achieved seamless integration of Chinese - standard and international - standard rails, saving costs by 15%.​

• What is the significance of rail interchangeability technology for railway globalization?​

Rail interchangeability technology breaks down standard barriers, reducing the procurement and transportation costs of rails in transnational railway construction by over 30% and shortening the construction period by 20%. It promotes technical collaboration in international projects such as the Belt and Road Initiative, facilitates the mutual recognition of railway standards among countries, enhances the international competitiveness of Chinese railway equipment and technology, and accelerates the globalization process of railway infrastructure.