Performance Requirements and Material Selection of Track Pads
What are the core performance indicators of under-rail base plates?
The core performance indicators of under-rail base plates include Shore hardness, compression set and impact energy absorption. The Shore hardness of rubber base plates needs to be controlled at 60±5 degrees to ensure both supporting force and elasticity. The compression set is ≤25%, which can prevent loss of buffering function after long-term compression. The impact energy absorption is ≥97%, which can effectively buffer the impact force when trains pass. In addition, the base plate must have good insulation performance and aging resistance, with a service life of not less than 15 years. These indicators collectively determine the buffering effect and service stability of the base plate.
What are the advantages of ACF artificial cartilage material base plates?
ACF artificial cartilage material is an excellent choice for under-rail base plates, with better buffering performance compared to ordinary rubber base plates. It has higher impact energy absorption efficiency, which can better absorb wheel-rail vibrations and reduce noise. This material has smaller compression set and can maintain good elastic recovery ability after long-term use. ACF material has more outstanding aging resistance and fatigue resistance, and can adapt to complex track environments. Using such base plates can significantly improve the smoothness of train operation and extend the overall service life of the track system.
What are the requirements for the installation direction of under-rail base plates?
There are clear directional regulations for the installation of under-rail base plates; rubber base plates should be laid with "notches facing the inner side of the track" to avoid reverse installation. Some types of base plates have color identifiers, such as insulated buffer base plates with blue side down and under-rail base plates with white side up, facilitating identification by construction personnel. During installation, it is necessary to ensure that the base plate is completely closely attached to the rail-bearing surface, with no warping or misalignment at the edges, and the gap ≤0.5mm. Skewed or reverse installation of the base plate will cause uneven force bearing, aggravate local wear, and affect the buffering effect. Strict installation according to direction is the foundation for ensuring the performance of the base plate and track stability.
What are the differences in requirements for under-rail base plates among different line types?
High-speed railways have higher requirements for the buffering performance and stability of base plates, requiring the selection of high-elasticity and low-deformation high-quality materials. Due to large loads, heavy-haul railways require base plates to have higher compressive strength and wear resistance to prevent premature damage. Ordinary railways can use cost-effective ordinary rubber base plates to meet basic buffering needs. For lines in coastal or humid areas, the base plate must additionally have anti-corrosion and moisture-proof performance to avoid accelerated material aging. Different line types require targeted adjustments to the performance parameters and material selection of base plates to achieve optimal adaptation.
What impacts can the damage of under-rail base plates cause to the track system?
Base plate damage will lead to reduced buffering performance, and the vibrations and impact forces during train operation will be directly transmitted to the sleepers and subgrade. Uneven force bearing will aggravate the wear of rails and sleepers, shortening their service life. Damaged base plates may cause rail displacement, affecting gauge and elevation accuracy and endangering driving safety. After the base plate is damaged, the insulation performance decreases, which may cause failures of the track signal system. Timely replacement of damaged base plates is an important part of daily track maintenance, which can prevent small problems from expanding into serious safety hazards.