Specification Conversion and Adaptation of Foreign Standard Rails
- How to convert European standard UIC54 rails to similar domestic specifications?
European standard UIC54 rails have a height of 156mm, a rail head width of 70mm, a web thickness of 14mm, and a weight of 54kg per meter. When converted to similar domestic specifications, its height is close to that of domestic 50kg/m rails (152mm), and there are certain differences in rail head width and web thickness compared with domestic 60kg/m rails (rail head width 73mm, web thickness 16.5mm). In practical applications, the fastener system needs to be adjusted, such as using special clamp to adapt to the external dimensions of UIC54 rails and ensure uniform distribution of clamping force.
- Which domestic rails have better compatibility with American standard AREMA 115RE rails?
American standard AREMA 115RE rails weigh 115 pounds per yard (about 52.16kg/m), with a height of 167.64mm and a rail head width of 68.58mm. Compared with domestic 50kg/m and 60kg/m rails, its weight and height are between the two. The domestic 60kg/m rails have better compatibility. By adjusting the thickness of the under-rail pad (increasing by 5-8mm), the height difference can be compensated, and at the same time, a suitable fishplate can be replaced to ensure connection strength and achieve better compatibility between AREMA 115RE rails and the domestic track system.
- How to deal with different rail base slopes of foreign standard rails from domestic requirements?
The rail base slope of some foreign standard rails is 1:40, different from the commonly used 1:30 rail base slope in China. When dealing with it, before laying foreign standard rails, the surface of the sleeper can be processed. By grinding or adding a wedge-shaped pad, the slope of the sleeper surface can be adjusted to 1:40 to ensure a tight fit between the rail and the sleeper and avoid stress concentration. In curve sections, the adjustment of the rail base slope also needs to be comprehensively considered in combination with the super elevation of the outer rail to ensure the smooth operation of the train.
- How can the fastener systems of different foreign standard rails be made universal with domestic ones?
For foreign standard rails matched with the German standard SKL series fasteners, after being introduced into China, the elastic clip part of the fastener can be replaced with a commonly used domestic elastic clip model (such as Type II elastic clip), and the size and shape of the 扣板 can be adjusted to adapt to the rail head profile of the foreign standard rail. At the same time, the embedded sleeves of the fasteners should be inspected, and if necessary, replaced with sleeves with the same anchoring method as in China to ensure that the fasteners are firmly installed and meet domestic track maintenance requirements.
- What are the splicing methods when the length specifications of foreign standard rails are inconsistent with domestic ones?
Common lengths of foreign standard rails are 18m, 24m, etc., different from the domestic standard lengths of 12.5m and 25m. When splicing, on-site welding can be used. After cutting the foreign standard rails to an appropriate length, they can be welded to domestic rails. The welding process needs to be strictly controlled, such as using narrow-gap welding technology to reduce welding deformation and ensure weld quality. After welding, the welds should be inspected by flaw detection (such as ultrasonic flaw detection) to ensure no defects and meet the track strength requirements.