Rail Pad
The rail pad, also known as bottom plate, is an elastic polyurethane pad assembled between the rails and sleeper to protect the top of the sleeper from wear and impact. The initial stiffness of the rail pad is not so high that the deformation of the rails under the load of the spring is very large. This mechanism ensures that the rail pad moves as close as possible to realize close contact with the track.
As a professional manufacturer of rail fasteners, AGICO is able to produce rail pads of various rail pads, such as UIC54, UIC60, BS80lbs, BS100lbs and so on. In addition, we can offer custom-made track pads according to drawings or samples.
Rail pads Functions
Rail pads plays 2 main parts in railway system. It can diminish shock and impact on steel rail, as well as reduce resonant vibration aroused from the concrete sleepers (lowest resonant frequency about 200Hz), and absorb the vibration deviation (about 0.12mm amplitude, 1000Hz) of the track part between sleepers. What’s more, rail pads can prevent abrasion and crushing of the sleeper under the foot of the track.
The rubber rail pads are usually designed to have a specific load-deflection characteristic. The initial stiffness of the pads is designed to be very low, making their deformation under the spring toe load quite large. This ensures that despite any vertical movement of the rail, the pad is still in close contact with it. When the wheel is above the pad, the stiffness of the track must be high to prevent large movement, resulting in loose metal spring washers. This load deflection characteristic can be obtained by introducing grooves in the rubber pad.
Rail pad under the track can achieve such functions
- Distribute load to a large surface
- Eliminate load concentration and fatigue stress
- Absorb the uneven surface contact between rail and support
- Weaken rail noise and vibration
- Seal the gap between the bottom of the track and the top of the sleeper
- Reduce the wear of steel rail and rail sleeper
Materials for rail pads
After years of rail pad manufacturing experience, we have developed a range of high performance flexible rail pads to meet rigid demand and a variety of application areas: from standard railways to heavy-duty lines, special rail pads for E-clamp track fastening systems and SKL type track fastening system. The materials includes HDPE / EVA / rubber material, which possess the following characteristics.
HDPE
| Technical Parameter | Unit | Technical Requirement | Value |
|---|---|---|---|
| Density | g/cm3 | 0.95-0.98 | 0.95 |
| Tensile Strength | Mpa | ≥19 | 19 |
| Elongation | % | >80 | 150 |
| Melting Point | °C | 170-190 | 190 |
| Insulation Resistance | Ω | ≥1×1010 | 3.5 ×1010 |
| Hardness | A | ≥98 | 98(A) |
EVA: Polyethylene 80%, Vinyl Acetate 20%
| Technical Parameter | Unit | Technical Requirement | Value |
|---|---|---|---|
| Density | g/cm3 | 0.95-0.98 | 0.95 |
| Tensile Strength | Mpa | ≥15 | 16 |
| Elongation | % | >500 | 550 |
| Melting Point°C | °C | 170-190 | 170 |
| Insulation Resistance | Ω | ≥1×1010 | 5.0 ×1010 |
| Hardness | A | ≥90 | 92(A) |
Rubber
| Technical Parameter | Unit | Value |
|---|---|---|
| Stiffness | KN | 90-130 |
| Hardness Shore A°C | °C | 72-80degree |
| Electronic Resistance | Ω | ≥ 106 |
| Tensile Strength before Aging | Mpa | ≥12.5 |
| Elongation before Aging | % | ≥250 |
Rail Pads production process
- Rubber compound preparation
- Mixed by an internal mixer or a two-roll mill. In terms of the internal mixer, the raw materials are processed by single or double stage, during which the masterbatch prepared ahead of time is finalized by adding curing agents to the twin roll mill.
- Shaping and curing
- Compression or Injection molding
- End products trimming
- Ready for use
Rail pads for E-type rail fastening system
Rail pads applied in E-type rail fastening system plays the same role as rail insulators, who insulate the steel track and the tie sleeper below it, thus reducing the vibration and noise. The rail pad function with E-clips, rail insulator and rail shoulders to constitute a E-type rail fastening system.
Rail pads for SKL rail fastening system
Rail pads work together with SKL clips, screw spikes, plastic dowel and guide plates to form a SKL fastening system. With higher level of elasticity, it contributes to realizing quiet running of the rolling stocks.
Rubber rail pads for concrete sleepers
| Material | Rubber |
|---|---|
| Standard: | TB/T2626-95 |
| Application: | 43kg/m ,50kg/m, 60kg/m, 75kg/m rail |
| Models: | 43-7-7, 43-10-7, 50-7-9, 50-10-9, 60-10-17, 60-12-17 |
| Operation Temperature: | -50~70 degrees |
| Certificate: | ISO9001:2008 |
| Notes: | Should be stored in clean, ventilated place. Don’t put under direct sunlight, and keep away from heat sources and chemical reagents. Don’t touch oil, organic solvent and other chemicals. |
High-elastic grooved EVA/HDPE/rubber rail pads
With high elasticity, EVA/HDPE/rubber rail pads is applicable to various types of rail such as UIC54, UIC60, BS80lbs and BS100lbs. We can provide all possible design according to customers’ demand. Rail Pads without grooves is also available.
