High-speed railway quality requirements for steel rails

High-speed Rail Steel Rail Quality Requirements

High-speed railway has a large span, special requirements for the line structure and higher speed and other characteristics. Therefore, its quality requirements for steel rails are also relatively high. In general, steel rails used in high-speed railway are 65 kg/m in length, and the most common type of rails used is quenched and tempered rails. A higher grade of rail steel with a tensile strength of 770 MPa, an elongation of 13%, a reduction in area of 15%, and a hardness of 272 HRB is required for high-speed railway.

The physical and chemical composition of rail steel is also strictly controlled. The quenched and tempered rail steel mainly contains carbon, silicon, manganese, chromium and other elements, whose content needs to be strictly controlled. Especially for carbon, the content of high-speed railway steel rail needs to be strictly controlled below 0.80%.

The performance of high-speed railway steel rails is determined by the quality of the steel. The impact toughness, fatigue strength, shear strength and welding performance of the rail steel shall be strictly tested in order to control the occurrence of railhead damage, fatigue crack and weld line cracks.

In addition, the surface quality of high-speed railway steel rails must also meet certain requirements. The surface of the rails should be uniform, without any unevenness, inclusions and other defects. In order to ensure the evenness and smoothness of the steel surface, the high-speed railway steel rail must meet the requirements of the surface undulation before rolling and the surface quality after rolling.

To sum up, the requirements for the quality of high-speed railway steel rails is much higher than that of ordinary railway steel rails. Only qualified steel rails will be used in the construction of high-speed railways, so that the safety of high-speed railway can be guaranteed.

The quality requirements of steel rails used in high-speed railway

High-speed railway is a kind of rapid railway transportation system. The quality requirements of steel rails used in high-speed railway are relatively strict, which must meet several conditions:

First of all, high-speed railway steel rails need to be certified by national metallurgical standards and products. These steel rails must have good elasticity and tensile strength, and have sufficient bearing capacity, so as to cope with the rail fatigue and wear problems caused by high-speed operating. Therefore, the hardness and uniformity of the rail surface of the high-speed railway steel rails need to be high and uniform.

In addition, high-speed railway steel rails must be sound and smooth, and internal and external defects are not allowed. There should be no cracks, holes, rolling marks or other defects on the surface. The joint of the two steel rails must be smooth, and the machining of the joints must meet the requirements of the drawings.

Furthermore, the rail length and width of high-speed railway steel rails must comply with relevant production standards and specifications. The height and width of the head are also required to meet national standards. The steel rails must be qualified after matching with rail sleepers and track bolts, so as to reduce the possibility of rail derailment.

Therefore, steel rails used in high-speed railway are required to have high quality, so as to ensure the safe and smooth operation of the railway. It is hoped that the unit responsible for quality inspection will strictly comply with the above criteria to ensure the safety of high-speed railway.