Fastening System Composition and Functions
1. What components does the fastening system mainly consist of?
The fastening system mainly consists of components such as elastic clips, bolts, gauge plates, and rubber pads. Elastic clips are used to press the rails, providing clamping force to prevent the lateral movement of the rails; bolts are responsible for connecting and fastening various components to ensure the stability of the entire system; gauge plates are used to adjust and maintain the gauge, making the distance between the rails meet the standard; rubber pads play a role in buffering and shock absorption, reducing the impact of train operation on the track structure and extending the service life of track components.
2. What is the action mechanism of elastic clips in the fastening system?
Elastic clips generate clamping force through their own elastic deformation. During installation, external force is applied to the elastic clips to cause bending deformation. After installation, they generate continuous pressure on the rails to restore their original shape, firmly fixing the rails on the sleepers. Different types of elastic clips, such as Type I, Type II, and Type III, have different clamping forces and elasticity due to different structural designs. Type III elastic clips have a more reasonable structural design, can generate larger and more stable clamping force, and are widely used in high-speed railways and other lines with high requirements for track stability.
3. What impact does the selection of bolts have on the performance of the fastening system?
The strength grade, material, and specification of bolts need to be compatible with other components of the fastening system. Bolts with low strength grades are prone to deformation and fracture under long-term train vibration and load, leading to loose components and affecting track safety. In terms of material, if ordinary carbon steel bolts are used in humid and corrosive environments, they are prone to rust and corrosion, reducing the connection strength. Instead, bolts treated with galvanizing, Dacromet, or stainless steel should be selected. Improper specifications, such as mismatched bolt diameter and the hole diameter of connecting components, will cause installation difficulties and fail to provide sufficient fastening force, affecting the overall performance of the system.
4. How do gauge plates realize the function of gauge adjustment and maintenance?
Gauge plates usually have different thickness and shape designs. By selecting gauge plates of different thicknesses to install between the rail and the sleeper, the lateral position of the rail can be adjusted, thereby realizing gauge adjustment. During train operation, relying on their own structural strength and tight cooperation with the rail and sleeper, gauge plates resist the displacement of the rail caused by the lateral force of the train and maintain the stability of the gauge. Some adjustable gauge plates can also be fine-tuned according to the actual gauge change during the use of the track to ensure that the gauge always meets the standard.
5. How much impact do rubber pads have on the shock absorption effect of the fastening system?
Rubber pads have a significant impact on the shock absorption effect of the fastening system. Their good elasticity can effectively absorb the vibration energy generated by train operation and reduce the transmission of vibration to the sleepers and ballast. If the rubber pad has insufficient elasticity or becomes hard due to aging, the shock absorption effect will be greatly reduced, and the vibration of train operation will be intensified. This not only increases the wear of track components but also may cause the fasteners to loosen, affecting the stability of the track structure. In high-speed railways and urban rail transit, higher requirements are put forward for the shock absorption performance of rubber pads, and high-elasticity and aging-resistant rubber materials should be selected to ensure the smooth operation of trains and passenger comfort.