Types and Functions of Fastening Systems
- What is the working principle of common fastening system types?
The elastic strip fastener generates clamping force through the elastic deformation of the elastic strip, tightly fastening the steel rail on the sleeper. It uses the elastic force of the elastic strip to adapt to the small displacement of the steel rail caused by train loads. The 扣板 fastener relies on the friction between the 扣板 and the rail bottom and the bolt fastening force to fix the steel rail. By tightening the bolt, the 扣板 presses the rail bottom to prevent the steel rail from moving.
- How to adjust the clamping force of different fastening systems?
For elastic strip fasteners, the clamping force is generally adjusted by replacing different types of elastic strips or adjusting the initial installation state of the elastic strips. For example, when installing, adjust the bending angle of the elastic strip. The larger the angle, the greater the clamping force. The 扣板 fastener mainly controls the clamping force by adjusting the tightening torque of the bolt. Use a torque wrench to tighten the bolt according to the specified torque to achieve the corresponding clamping force requirement.
- What is the applicability of fastening systems in different railway environments?
On high-speed passenger dedicated lines, elastic strip fasteners with high clamping force, good elasticity, and the ability to adapt to high-frequency vibrations, such as WJ-7 and WJ-8 fasteners, need to be selected to ensure the stability of the steel rail during high-speed driving. On heavy-haul railways, fastening systems with strong bearing capacity and good fatigue resistance, such as some strengthened 扣板 fasteners, should be selected to withstand the repeated action of trains with large axle loads. In urban rail transit, considering the needs of noise reduction and vibration reduction, fastening systems with vibration reduction components such as rubber pads can be used.
- What are the key points of daily maintenance of the fastening system?
Regularly check the fastening state of the fasteners to prevent bolts from loosening. If loosening is found, tighten them to the specified torque in time. Check whether components such as elastic strips and 扣板 are deformed or broken, and replace them in time if damaged. Clean the debris around the fasteners to avoid affecting the clamping force and the normal operation of the fasteners. At the same time, carry out anti-rust treatment on the fasteners to extend the service life.
- How does the performance of the fastening system affect the track geometry?
If the clamping force of the fastening system is insufficient, the steel rail is prone to lateral and longitudinal displacement, resulting in the expansion or reduction of the gauge and affecting the track smoothness. A fastening system with poor elasticity cannot effectively buffer the train load, which will cause excessive deformation of the steel rail, 破坏 the height and level state of the track, increase the train running resistance and wheel-rail wear, and seriously endanger driving safety.