what is usp in track railway?
In railway track, USP stands for Under Sleeper Pads, which are resilient, elastic layers placed under sleepers (ties) in ballasted tracks to absorb vibration, improve load distribution, protect the ballast from degradation, reduce maintenance costs, and enhance overall track stability and lifespan. Made from materials like polyurethane or rubber, USPs act like shock absorbers, cushioning the impact from passing trains, especially beneficial for high-speed lines and turnouts.
Why are railway pads made using rubber?
- Vibration & Noise Reduction: Absorbs high-frequency vibrations from passing trains, making journeys smoother and reducing noise pollution.
- Shock Absorption: Cushions impact, protecting the rail and sleepers from intense loads and fatigue.
| Rubber Rail Pad | ||
| Technical Parameter | Unit | Value |
| Stiffness | KN | 90-130 |
| Hardness Shore A | ℃ | 72-80 degree |
| Electronic Resistance | Ω | ≥ 106 |
| Tensile Strength before Aging | Mpa | ≥12.5 |
| Elongation before Aging | % | ≥250 |
- Wear Protection: Prevents direct contact between steel rails and sleepers, stopping abrasion and crushing of the sleeper material.
- Load Distribution: Spreads the concentrated load from the rail over a larger area of the sleeper.
- Electrical Insulation: Provides electrical isolation, crucial for track circuits and signaling systems.
Why Need Under Sleeper Pads For Railroad Track?
The under sleeper pad is a rubber pad that is laid under the railway sleeper, which is a kind of rail pad.
In order to reduce the vibration and noise generated by wheel-rail contact, the usual method used in railway engineering is to place under sleeper pad under the rails, the sleepers and the ballasts. Rail pads can be divided into under-rail rubber pads, under sleeper pads and under- ballast rubber pads depending on the location of use. Three types of rail pads are sequentially reduced in stiffness. The under-rail rubber pad needs to be laid on all rail lines, and the under sleeper pads and under- ballast rubber pads are laid on different sections according to the shock absorbing requirements.
The under sleeper pads are mainly used in special vibration-damping areas, such as tunnels, bridges and culverts, etc. The lower part of these sections is a rigid foundation, and the stacking height of the ballast is insufficient, resulting in insufficient track elasticity. Laying under sleeper pads under the railway sleeper can effectively solve the problem of insufficient elasticity. The under sleeper pad material under the railway sleeper is mainly composed of EPDM rubber and neoprene, and the part of the bottom in contact with ballast must have good puncture resistance. In addition, good mechanical properties, aging resistance and fatigue properties are all necessary characteristics of under sleeper pads.
As a professional rubber rail pad manufacturer GNEE RAILWAY RAILWAY can produce various standards of rubber rail pads and other rail fasteners. If you want to build a railway line, do not hesitate to contact us, we can supply all types of rubber rail pads with different materials. If necessary, we can make customized rubber rail pad production.