Railway pad production process
Rail pads can prevent rail sleeper abrasion and the crushing of the sleeper under the rail foot. Rubber rail pads are normally designed to a specified load-deflection characteristic. The initial stiffness of the rail pad is designed to be low so that that their deformations under the springs toe loads is quite substantial.
For railway engineers and procurement managers, understanding how a component is made is just as important as knowing its specifications. The Railway Pad Production Process is a sophisticated sequence of chemical engineering and precision molding. A high-quality Rail Rubber Pad is not just stamped out; it is engineered to survive millions of load cycles.
Step 1: Material Selection and Compounding
The journey of a durable Railroad Pad begins in the mixing room. Depending on the required track stiffness, materials such as Natural Rubber, SBR, HDPE, or EVA are selected. At GNEE RAIL, raw polymers are mixed with reinforcing agents, antioxidants, and curing agents in precise ratios. This "compounding" stage is critical, as it defines the Rail Elastic Pad's future resistance to UV rays, oil, and extreme temperatures.
Step 2: Vulcanization and Molding
- This is the heart of the manufacturing process. The compounded material is placed into high-precision steel molds.
- For rubber-based pads, the material undergoes vulcanization under high heat and pressure. This chemical process transforms the soft rubber into a resilient, elastic form.
| 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 |
- For plastic-based pads (like HDPE), an injection molding process is typically used.
| HDPE Rail Pad | |||
| 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 | ℃ | 170-190 | 190 |
| Insulation Resistance | Ω | ≥1×1010 | 3.5 ×1010 |
| Hardness | A | ≥98 | 98(A) |
- Advanced automated presses ensure that every Rubber Track Pad forms with uniform density and exact dimensions, eliminating internal voids that could lead to premature failure.
Step 3: Trimming and Finishing
Once removed from the mold, the pads undergo deflashing to remove excess material (flash) from the edges. This ensures a clean fit within the fastening system. High-performance pads may undergo a secondary curing process to stabilize their dimensions further.
Step 4: Rigorous Testing
Before leaving the factory, the Rail Pads must prove their worth. Quality control includes Static and Dynamic Stiffness tests, fatigue endurance testing (often up to 3 million cycles), and electrical resistance checks.
The GNEE RAIL Manufacturing Standard
At GNEE RAIL, we control every step of the production line to meet international standards like UIC, DIN, and AREMA. Whether producing standard guide plates or complex Under Sleeper Pads, our commitment to process precision guarantees a product that reduces maintenance costs for your railway project.
Our EVA/HDPE/rubber rail pads are with high elasticity, applying to types for rails such as rail UIC54, UIC60, BS80lbs,BS100lbs, and sizes as ordered. The pads can be customized with or without grooves, in various possible designs, depending on customers' requirements.