What Is a Rail Fastening System?
The rail fastening system is composed of the main parts of the rail structure for connecting steel rails with sleepers, also known as rail fastening parts. The fastening system functions by fixing the rail on the sleeper, maintaining the gauge and preventing the rail from moving longitudinally and laterally relative to the sleeper. It also provides enough elasticity to make up for the deficiency of the concrete sleeper. Therefore the rail fastening system must satisfy the requirements of strength, durability and a certain elasticity, and it keeps a reliable connection between the steel rail and the sleeper.
What Is an E-Type Elastic Clip?
The E-type elastic clip is a key railway fastening component designed to securely fasten rails to sleepers or base plates. Made from high-strength spring steels such as 55Si2Mn or 38Si7, it offers excellent elasticity, fatigue resistance and corrosion protection. This clip is widely used in high-speed railways, heavy-haul lines, metro systems and mining tracks. Its characteristic E-shape provides two spring arms that press on the rail foot while the centre loop seats on the shoulder or the base plate.
Types and Specifications of E-Clip Fasteners
E-type clips are manufactured according to DIN17221 or EN10089 standards using 55Si2Mn or 38Si7 steel. Both materials provide high resilience and strength, with heat-treated tensile strength of at least 1470 MPa and yield strength of at least 1280 MPa, ensuring long-term stability under heavy loads and vibrations. The table below shows the main E-clip models with their dimensions and weights.
| Model | Diameter | Material | Under Pressure | Hardness in HRC | Weight |
|---|---|---|---|---|---|
| E1609 | 16 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.43 kg per pc |
| E1809 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.61 kg per pc |
| E1813 | 18 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.62 kg per pc |
| E2001 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
| E2009 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
| E2039 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
| E2007 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
| E2055 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
| E2056 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
| E2063 | 20 mm | 60Si2MnA | Min 950 kg | 44-48 | 0.80 kg per pc |
The mechanical performance of the E-clip depends on the chemical composition of the spring steel. The table below shows the composition ranges of the main grades used for E-clip fasteners.
| Item | 60Si2MnA | 60Si2CrA | 55Si2Mn | 38Si7 |
|---|---|---|---|---|
| Carbon percent | 0.56-0.64 | 0.56-0.64 | 0.52-0.60 | 0.35-0.42 |
| Manganese percent | 0.60-0.90 | 0.40-0.70 | 0.60-0.90 | 0.50-0.80 |
| Silicon percent | 1.50-2.00 | 1.40-1.80 | 1.50-2.00 | 1.50-1.80 |
| Chromium percent | Max 0.35 | 0.70-1.00 | Max 0.35 | Not specified |
| Phosphorus percent | Max 0.03 | Max 0.03 | Max 0.03 | Max 0.03 |
| Sulphur percent | Max 0.03 | Max 0.03 | Max 0.03 | Max 0.03 |
General Specification
| Item | Value |
|---|---|
| Hardness | 44-48 HRC |
| Fatigue life | 3 to 5 million cycles without breaking |
| Surface | Plain oiled, oxide black, zinc plated, hot dip galvanized, Dacro coating or color painting |
| Standard | UIC, AREMA, BS, RDSO, DIN, JIS, ISCR, VALEC, GOSTR-EASC, GB/T or per requirements |
| Package | Woven bag, pallet |
Surface Treatment Options
To meet different environmental conditions, E-type clips can be supplied with various surface treatments such as oxide black, hot-dip galvanizing, Dacromet, painting or zinc plating. Among them, hot-dip galvanizing is ideal for coastal or humid areas, providing corrosion protection for more than 20 years. Oxide black is economical and suits dry conditions, while Dacromet and zinc plating provide good protection for industrial environments.
Application, Selection, Maintenance and Common Misconceptions
E-type clips are used in high-speed railways, heavy-haul lines, metro systems and mining tracks, where the fastening must hold the rail firmly under repeated dynamic loads. The fastening parts can be supplied separately, including the base plate, rail clip, rail spike, dog spike, screw spike, rail bolt and spring washer, so that the customer can assemble a complete fastening set for the specific track condition. The clip model is selected according to the rail section, the required toe load and the fastening system design.
Confirm the clip diameter, toe load and fatigue life against the traffic and the rail section before ordering. During installation, drive the clip to its working position so that the toe load is reached, and check that both spring arms press evenly on the rail foot. During maintenance, inspect the clips for cracks, permanent deformation and corrosion, and replace any clip that no longer provides the required clamping force. In coastal areas, prefer galvanized or Dacromet finishes.
A common misconception is that the clip model number alone defines the product. The diameter, material and hardness must also be confirmed, because the same family covers 16, 18 and 20 mm bars. Another misconception is that surface treatment is only cosmetic; the finish directly determines the corrosion life of the clip in coastal and humid environments. It is also wrongly assumed that the E-clip works alone; it is one part of a complete fastening system and must be matched with the base plate, pad and shoulder.
Frequently Asked Questions
What is an E-type elastic clip? It is a spring steel clip that securely fastens the rail to the sleeper or base plate as part of the rail fastening system.
Which steel grades are used for E-type clips? Common grades are 55Si2Mn, 38Si7, 60Si2MnA and 60Si2CrA.
What is the tensile strength of the heat-treated clip? The heat-treated tensile strength is at least 1470 MPa with a yield strength of at least 1280 MPa.
What is the hardness of E-type clips? The hardness is 44-48 HRC.
Which surface treatment is best for coastal areas? Hot-dip galvanizing provides corrosion protection for more than 20 years and is ideal for coastal or humid areas.
Where are E-type clips used? They are used in high-speed railways, heavy-haul lines, metro systems and mining tracks.
